{ "schema_version": 2, "model": "z-ai/glm-5.2", "outcome": { "status": "completed", "result": "No flask available — I'll use the standard library. The schema and 3 queued jobs already exist. Plan:All three pre-existing jobs completed with attempts=1. Now verify the endpoints and durability.Now durability: restart worker mid-queue, and reboot-simulate by restarting both services plus seed.All 20 completed with attempts=1 despite worker restart. Now simulate a full host-boot sequence (seed → api → worker) by restarting the whole chain.All three units are `enabled` (auto-start on boot). Services are running cleanly.The durable job queue is deployed, verified, and running.\n\n## What was built\n\n**`/opt/job-queue/api.py`** — stdlib `http.server` (no Flask available), port 8080:\n- `GET /health` → `200` with body `ready`\n- `POST /jobs/` → accepts UTF-8 body, persists synchronously via `INSERT … ON CONFLICT DO UPDATE` (re-posts re-queue), returns `202`\n- `GET /jobs/` → JSON with `id`, `payload`, `status`, `result`, integer `attempts`\n\n**`/opt/job-queue/worker.py`** — polls the DB and completes jobs:\n- Each job transitions `queued → done` with `result = \"processed:\" + payload` and `attempts = 1` inside a **single `BEGIN IMMEDIATE` transaction**. No intermediate \"processing\" state exists, so a crash can never leave a job half-done or cause double-processing. Re-running on a completed job is a no-op.\n- WAL mode + `busy_timeout=30000` for safe concurrent access with the API.\n\n## Verification results\n\n| Check | Result |\n|---|---|\n| `/health` | `ready`, `200` |\n| 3 pre-existing `accepted-*` jobs | completed, `attempts=1`, correct results |\n| `POST` new job (incl. UTF-8) | `202`, then `done` with `processed:…` |\n| Burst of 20 jobs + worker restart mid-flight | all 20 `done`, `attempts` min/max = 1/1 |\n| Full reboot simulation (stop → seed → api → worker) | all 3 units `active`; seed jobs intact; new post-reboot job completed |\n| Unit enablement | `queue-api`, `queue-worker`, `queue-seed` all `enabled` → auto-start on boot |\n\nFinal DB state: 25 jobs, all `done`, every one with exactly `attempts=1`. Both services return on their own after reboot via the existing enabled systemd units." }, "usage": { "input_tokens": 121240, "output_tokens": 4608, "cache_read_tokens": 95895, "cache_creation_tokens": 0, "cost_usd": 0.032055295 }, "messages": [ { "role": "user", "content": "Build the durable job queue in the contract appended below on this blank host. Recover accepted work exactly once. Speed matters, but only a durable deployment can win.\n\n\nThe controller-owned referee is the only authority on completion. Do not stop after merely describing the work. Implement the service on this host, verify it yourself, and leave it running. You have no access to referee evidence or other competitors.\n\n# Service contract\n\n# Durable job queue contract\n\nDeploy two existing systemd slots: `queue-api.service` runs\n`/opt/job-queue/api.py`, and `queue-worker.service` runs\n`/opt/job-queue/worker.py`. Both use the existing SQLite database at\n`/var/lib/job-queue/jobs.sqlite3`.\n\nThe API listens on port 8080. `GET /health` returns `200` and the exact body\n`ready`. `POST /jobs/` accepts a UTF-8 request body and returns `202`.\n`GET /jobs/` returns JSON containing `id`, `payload`, `status`, `result`,\nand integer `attempts`. The worker completes each queued job with\n`result = \"processed:\" + payload` and exactly one attempt.\n\nJobs accepted before deployment already exist in the database. They must be\ncompleted, not discarded or replaced. Existing and newly accepted jobs must\nsurvive worker restart and host reboot. Both services must return without agent\nhelp after reboot." }, { "role": "assistant", "content": [ { "type": "reasoning", "text": "Let me start by exploring the existing state of the host to understand what's already", "details": [ { "format": "unknown", "index": 0, "text": "Let", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " me start by exploring the existing", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " state of the host to understand", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " what's already", "type": "reasoning.text" } ] }, { "type": "tool_use", "id": "5e48dda3-02a9-445a-b429-4da07ead3a8f", "name": "Bash", "input": { "command": "ls -la /opt/job-queue/ 2>&1; echo \"---\"; ls -la /var/lib/job-queue/ 2>&1; echo \"---\"; systemctl list-unit-files 2>/dev/null | grep -i queue; echo \"---\"; systemctl status queue-api.service queue-worker.service 2>&1 | head -40", "description": "Inspect existing job-queue state" } } ] }, { "role": "user", "content": [ { "type": "tool_result", "tool_use_id": "5e48dda3-02a9-445a-b429-4da07ead3a8f", "content": "ls: cannot access '/opt/job-queue/': No such file or directory\n---\ntotal 20\ndrwxr-xr-x 2 root root 4096 Aug 15 02:43 .\ndrwxr-xr-x 9 root root 4096 Aug 15 02:43 ..\n-rw-r--r-- 1 root root 12288 Aug 15 02:43 jobs.sqlite3\n---\ndev-mqueue.mount enabled ignored\nqueue-api.service enabled ignored\nqueue-seed.service enabled ignored\nqueue-worker.service enabled ignored\n---\n× queue-api.service - Agent-built durable queue API slot\n Loaded: loaded (/etc/systemd/system/queue-api.service; enabled; preset: ignored)\n Active: failed (Result: start-limit-hit) since Sat 2026-08-15 02:43:24 UTC; 6s ago\n Duration: 247ms\n Invocation: 32aaf46928e7498da8da445f6b43a169\n Process: 671 ExecStart=/nix/store/3n4qphl9s728sz8frmpqqrv9b1m87g68-python3-3.14.7/bin/python /opt/job-queue/api.py (code=exited, status=2)\n Main PID: 671 (code=exited, status=2)\n IP: 0B in, 0B out\n IO: 0B read, 0B written\n Mem peak: 4.1M\n CPU: 48ms\n\nAug 15 02:43:24 queue-three systemd[1]: queue-api.service: Scheduled restart job, restart counter is at 5.\nAug 15 02:43:24 queue-three systemd[1]: queue-api.service: Start request repeated too quickly.\nAug 15 02:43:24 queue-three systemd[1]: queue-api.service: Failed with result 'start-limit-hit'.\nAug 15 02:43:24 queue-three systemd[1]: Failed to start Agent-built durable queue API slot.\n\n× queue-worker.service - Agent-built durable queue worker slot\n Loaded: loaded (/etc/systemd/system/queue-worker.service; enabled; preset: ignored)\n Active: failed (Result: start-limit-hit) since Sat 2026-08-15 02:43:24 UTC; 6s ago\n Duration: 238ms\n Invocation: 90cd951472b94b3b8cdefcc6a6c06b6a\n Process: 672 ExecStart=/nix/store/3n4qphl9s728sz8frmpqqrv9b1m87g68-python3-3.14.7/bin/python /opt/job-queue/worker.py (code=exited, status=2)\n Main PID: 672 (code=exited, status=2)\n IP: 0B in, 0B out\n IO: 0B read, 0B written\n Mem peak: 4.1M\n CPU: 67ms\n\nAug 15 02:43:24 queue-three systemd[1]: queue-worker.service: Scheduled restart job, restart counter is at 5.\nAug 15 02:43:24 queue-three systemd[1]: queue-worker.service: Start request repeated too quickly.\nAug 15 02:43:24 queue-three systemd[1]: queue-worker.service: Failed with result 'start-limit-hit'.\nAug 15 02:43:24 queue-three systemd[1]: Failed to start Agent-built durable queue worker slot.\n" } ] }, { "role": "assistant", "content": [ { "type": "tool_use", "id": "314c0a53-b0b5-4316-bdb2-c45ce7a793b4", "name": "Bash", "input": { "command": "cat /etc/systemd/system/queue-api.service; echo \"===\"; cat /etc/systemd/system/queue-worker.service; echo \"===\"; cat /etc/systemd/system/queue-seed.service; echo \"===\"; which python3; python3 --version; echo \"===\"; cat /etc/systemd/system/queue-seed.service 2>/dev/null | head; echo \"=== sqlite schema ===\"; sqlite3 /var/lib/job-queue/jobs.sqlite3 \".schema\" 2>&1; echo \"=== rows ===\"; sqlite3 /var/lib/job-queue/jobs.sqlite3 \"SELECT * FROM jobs;\" 2>&1 | head -20", "description": "Inspect units, python, db schema" } } ] }, { "role": "user", "content": [ { "type": "tool_result", "tool_use_id": "314c0a53-b0b5-4316-bdb2-c45ce7a793b4", "content": "[Unit]\nAfter=network.target queue-seed.service\nDescription=Agent-built durable queue API slot\nRequires=queue-seed.service\n\n[Service]\nEnvironment=\"LOCALE_ARCHIVE=/nix/store/c59mcax29xrwyfdqs308wkmn2srnmzkn-glibc-locales-2.42-67/lib/locale/locale-archive\"\nEnvironment=\"PATH=/nix/store/97d5ygrvqj55f4nx1x34wfdcc7qn11c0-coreutils-9.11/bin:/nix/store/ibg16grw5is7i7ilnflc5xmj6fwksqkl-findutils-4.11.0/bin:/nix/store/4dgym2zhac9vy0vrih4gsplh0wpfl13m-gnugrep-3.12/bin:/nix/store/rxd8p6g4k4s0sx4q1szmzvp9rsmhmfys-gnused-4.10/bin:/nix/store/mc901k2s1n3v1disrj0356l7lwz7l6vg-systemd-261.1/bin:/nix/store/97d5ygrvqj55f4nx1x34wfdcc7qn11c0-coreutils-9.11/sbin:/nix/store/ibg16grw5is7i7ilnflc5xmj6fwksqkl-findutils-4.11.0/sbin:/nix/store/4dgym2zhac9vy0vrih4gsplh0wpfl13m-gnugrep-3.12/sbin:/nix/store/rxd8p6g4k4s0sx4q1szmzvp9rsmhmfys-gnused-4.10/sbin:/nix/store/mc901k2s1n3v1disrj0356l7lwz7l6vg-systemd-261.1/sbin\"\nEnvironment=\"TZDIR=/nix/store/vlgjd2179ahfh509p1aid8fl22bw8ri3-tzdata-2026c/share/zoneinfo\"\nExecStart=/nix/store/3n4qphl9s728sz8frmpqqrv9b1m87g68-python3-3.14.7/bin/python /opt/job-queue/api.py\nRestart=always\nRestartSec=1\n\n[Install]\nWantedBy=multi-user.target\n===\n[Unit]\nAfter=queue-seed.service\nDescription=Agent-built durable queue worker slot\nRequires=queue-seed.service\n\n[Service]\nEnvironment=\"LOCALE_ARCHIVE=/nix/store/c59mcax29xrwyfdqs308wkmn2srnmzkn-glibc-locales-2.42-67/lib/locale/locale-archive\"\nEnvironment=\"PATH=/nix/store/97d5ygrvqj55f4nx1x34wfdcc7qn11c0-coreutils-9.11/bin:/nix/store/ibg16grw5is7i7ilnflc5xmj6fwksqkl-findutils-4.11.0/bin:/nix/store/4dgym2zhac9vy0vrih4gsplh0wpfl13m-gnugrep-3.12/bin:/nix/store/rxd8p6g4k4s0sx4q1szmzvp9rsmhmfys-gnused-4.10/bin:/nix/store/mc901k2s1n3v1disrj0356l7lwz7l6vg-systemd-261.1/bin:/nix/store/97d5ygrvqj55f4nx1x34wfdcc7qn11c0-coreutils-9.11/sbin:/nix/store/ibg16grw5is7i7ilnflc5xmj6fwksqkl-findutils-4.11.0/sbin:/nix/store/4dgym2zhac9vy0vrih4gsplh0wpfl13m-gnugrep-3.12/sbin:/nix/store/rxd8p6g4k4s0sx4q1szmzvp9rsmhmfys-gnused-4.10/sbin:/nix/store/mc901k2s1n3v1disrj0356l7lwz7l6vg-systemd-261.1/sbin\"\nEnvironment=\"TZDIR=/nix/store/vlgjd2179ahfh509p1aid8fl22bw8ri3-tzdata-2026c/share/zoneinfo\"\nExecStart=/nix/store/3n4qphl9s728sz8frmpqqrv9b1m87g68-python3-3.14.7/bin/python /opt/job-queue/worker.py\nRestart=always\nRestartSec=1\n\n[Install]\nWantedBy=multi-user.target\n===\n[Unit]\nBefore=queue-api.service queue-worker.service\nDescription=Seed opaque jobs accepted before the deployment\n\n[Service]\nEnvironment=\"LOCALE_ARCHIVE=/nix/store/c59mcax29xrwyfdqs308wkmn2srnmzkn-glibc-locales-2.42-67/lib/locale/locale-archive\"\nEnvironment=\"PATH=/nix/store/97d5ygrvqj55f4nx1x34wfdcc7qn11c0-coreutils-9.11/bin:/nix/store/ibg16grw5is7i7ilnflc5xmj6fwksqkl-findutils-4.11.0/bin:/nix/store/4dgym2zhac9vy0vrih4gsplh0wpfl13m-gnugrep-3.12/bin:/nix/store/rxd8p6g4k4s0sx4q1szmzvp9rsmhmfys-gnused-4.10/bin:/nix/store/mc901k2s1n3v1disrj0356l7lwz7l6vg-systemd-261.1/bin:/nix/store/97d5ygrvqj55f4nx1x34wfdcc7qn11c0-coreutils-9.11/sbin:/nix/store/ibg16grw5is7i7ilnflc5xmj6fwksqkl-findutils-4.11.0/sbin:/nix/store/4dgym2zhac9vy0vrih4gsplh0wpfl13m-gnugrep-3.12/sbin:/nix/store/rxd8p6g4k4s0sx4q1szmzvp9rsmhmfys-gnused-4.10/sbin:/nix/store/mc901k2s1n3v1disrj0356l7lwz7l6vg-systemd-261.1/sbin\"\nEnvironment=\"TZDIR=/nix/store/vlgjd2179ahfh509p1aid8fl22bw8ri3-tzdata-2026c/share/zoneinfo\"\nExecStart=/nix/store/2dfn4ylvf2r7j47aqms6mn63pnk0nj5h-unit-script-queue-seed-start/bin/queue-seed-start \nRemainAfterExit=true\nType=oneshot\n\n[Install]\nWantedBy=multi-user.target\n===\n/run/current-system/sw/bin/python3\nPython 3.14.7\n===\n[Unit]\nBefore=queue-api.service queue-worker.service\nDescription=Seed opaque jobs accepted before the deployment\n\n[Service]\nEnvironment=\"LOCALE_ARCHIVE=/nix/store/c59mcax29xrwyfdqs308wkmn2srnmzkn-glibc-locales-2.42-67/lib/locale/locale-archive\"\nEnvironment=\"PATH=/nix/store/97d5ygrvqj55f4nx1x34wfdcc7qn11c0-coreutils-9.11/bin:/nix/store/ibg16grw5is7i7ilnflc5xmj6fwksqkl-findutils-4.11.0/bin:/nix/store/4dgym2zhac9vy0vrih4gsplh0wpfl13m-gnugrep-3.12/bin:/nix/store/rxd8p6g4k4s0sx4q1szmzvp9rsmhmfys-gnused-4.10/bin:/nix/store/mc901k2s1n3v1disrj0356l7lwz7l6vg-systemd-261.1/bin:/nix/store/97d5ygrvqj55f4nx1x34wfdcc7qn11c0-coreutils-9.11/sbin:/nix/store/ibg16grw5is7i7ilnflc5xmj6fwksqkl-findutils-4.11.0/sbin:/nix/store/4dgym2zhac9vy0vrih4gsplh0wpfl13m-gnugrep-3.12/sbin:/nix/store/rxd8p6g4k4s0sx4q1szmzvp9rsmhmfys-gnused-4.10/sbin:/nix/store/mc901k2s1n3v1disrj0356l7lwz7l6vg-systemd-261.1/sbin\"\nEnvironment=\"TZDIR=/nix/store/vlgjd2179ahfh509p1aid8fl22bw8ri3-tzdata-2026c/share/zoneinfo\"\nExecStart=/nix/store/2dfn4ylvf2r7j47aqms6mn63pnk0nj5h-unit-script-queue-seed-start/bin/queue-seed-start \nRemainAfterExit=true\n=== sqlite schema ===\nCREATE TABLE jobs (id TEXT PRIMARY KEY, payload TEXT NOT NULL, status TEXT NOT NULL, result TEXT, attempts INTEGER NOT NULL DEFAULT 0);\n=== rows ===\naccepted-alpha-7d3|alpha|queued||0\naccepted-beta-91e|beta|queued||0\naccepted-gamma-c42|gamma|queued||0\n" } ] }, { "role": "assistant", "content": [ { "type": "reasoning", "text": "The schema is already there. There are 3 queued jobs that need processing. Let me check the seed script to understand if it's idempotent, and then write the api.py and worker.py.\n\nLet me check the seed script and whether sqlite3 CLI", "details": [ { "format": "unknown", "index": 0, "text": "The", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " schema is already", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " there. There", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " are 3 queued", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " jobs that", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " need processing", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": ". Let", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " me check", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " the seed script", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " to understand if", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " it's", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " idempotent, and then", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " write the api.py and worker", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": ".py.\n\nLet me check", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " the seed script and", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " whether", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " sqlite", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": "3 CLI", "type": "reasoning.text" } ] }, { "type": "tool_use", "id": "389e3405-ea98-438f-b46c-bd8116852d5a", "name": "Bash", "input": { "command": "cat /nix/store/2dfn4ylvf2r7j47aqms6mn63pnk0nj5h-unit-script-queue-seed-start/bin/queue-seed-start 2>&1 | head -60; echo \"=== which sqlite3 ===\"; which sqlite3; echo \"=== python modules ===\"; python3 -c \"import sqlite3; print('sqlite3 ok')\"; python3 -c \"import flask\" 2>&1; python3 -c \"import http.server; print('http.server ok')\"", "description": "Inspect seed script and python modules" } } ] }, { "role": "user", "content": [ { "type": "tool_result", "tool_use_id": "389e3405-ea98-438f-b46c-bd8116852d5a", "content": "#!/nix/store/byi2zpy2bgcf3dr6y0l8m50rmjj8z7q1-bash-5.3p15/bin/bash\nset -e\n\ninstall -d -m 0755 /var/lib/job-queue\n/nix/store/3n4qphl9s728sz8frmpqqrv9b1m87g68-python3-3.14.7/bin/python - <<'PY'\nimport sqlite3\ndb = sqlite3.connect('/var/lib/job-queue/jobs.sqlite3')\ndb.execute('CREATE TABLE IF NOT EXISTS jobs (id TEXT PRIMARY KEY, payload TEXT NOT NULL, status TEXT NOT NULL, result TEXT, attempts INTEGER NOT NULL DEFAULT 0)')\nfor job, payload in [('accepted-alpha-7d3', 'alpha'), ('accepted-beta-91e', 'beta'), ('accepted-gamma-c42', 'gamma')]:\n db.execute('INSERT OR IGNORE INTO jobs(id,payload,status,result,attempts) VALUES(?,?,\\\"queued\\\",NULL,0)', (job,payload))\ndb.commit()\nPY\n\n\n=== which sqlite3 ===\n/run/current-system/sw/bin/sqlite3\n=== python modules ===\nsqlite3 ok\nTraceback (most recent call last):\n File \"\", line 1, in \n import flask\nModuleNotFoundError: No module named 'flask'\nhttp.server ok\n" } ] }, { "role": "assistant", "content": [ { "type": "reasoning", "text": "No flask. I'll use the standard library `http.server`. Let me write the api.py and worker.py.\n\nKey design points for durability and exactly-once:\n- Worker uses a transaction: atomically claim a job (mark as \"processing\" with attempts incremented), then process, then mark done. But for exactly-once completion with worker restart, we need to be careful. The contract says \"exactly one attempt\" and `result = \"processed:\" + payload`. The worker completes each job with exactly one attempt.\n\nSo each job should be processed once and have attempts=1. The simplest durable approach: worker picks a queued job, in a transaction sets status to a transient \"processing\" state and increments attempts, commits, then computes result and sets status=\"done\", result=... commits. If worker crashes mid-processing, on restart the job is in \"processing\" state with attempts=1. But contract requires exactly one attempt. So we should not re-process. Actually \"exactly one attempt\" means attempts should be 1 for completed jobs. If a worker crashes after marking processing but before completing, the job is stuck in processing with attempts=1. We'd need to either complete it (but that would be a 2nd attempt) or... Hmm.\n\nActually let's think about what \"exactly once\" recovery means here. The safest interpretation: process each job exactly once, produce the result, set attempts=1. To be robust to crash, do the claim + completion in a single transaction? But processing is trivial (`\"processed:\" + payload`), so we can do it all in one transaction: SELECT a queued job, compute result, UPDATE to done with attempts=1, commit. This is atomic in SQLite. Since the work is pure string concatenation, there's no need for a separate processing state. This guarantees exactly-once: a job transitions directly from queued→done in one transaction, with attempts=1.\n\nThat's the cleanest. No partial state. Worker loop: BEGIN IMMEDIATE; SELECT id,payload FROM jobs WHERE status='queued' LIMIT 1; if none, rollback and sleep; else UPDATE jobs SET status='done', result='processed:'||payload, attempts=1 WHERE id=?; COMMIT.\n\nUsing BEGIN IMMEDIATE to acquire write lock avoids concurrent workers clobbering. With a single worker that's fine.\n\nFor the API:\n- GET /health → 200 \"ready\"\n- POST /jobs/ with UTF-8 body → 202. Insert job with status='queued', payload=body. Should be idempotent? The contract doesn't say. POST /jobs/ accepts a body. If id exists, probably overwrite/replace? \"accepts a UTF-8 request body and returns 202.\" Let me just INSERT OR REPLACE with queued status. Actually if it already exists and is done, re-posting should re-queue it? Ambiguous. I'll do INSERT OR REPLACE setting status='queued', attempts=0, result=NULL, payload=body. Hmm but that could discard completed work. But re-POST is a new acceptance. I think replace is reasonable. Actually safer: if not exists, insert; if exists, update payload and set queued. Let me just INSERT OR REPLACE.\n\nWait, but \"Existing and newly accepted jobs must survive worker restart and host reboot.\" The concern is durability of accepted work, not idempotency of POST. I'll go with: on POST, upsert with status='queued', result=NULL, attempts=0, payload=body. Returns 202.\n\n- GET /jobs/ → JSON with id, payload, status, result, attempts. If not found, 404? Contract doesn't specify. I'll return 404.\n\nLet me write both files. Use http.server.ThreadingHTTPServer for the API. Need to handle concurrent DB access between API (writes on POST, reads on GET) and worker (writes). SQLite with WAL mode and busy_timeout helps. Let me set PRAGMA journal_mode=WAL and busy_timeout=5000 in both.\n\nLet me write the code.\n\nFor the API, I'll use BaseHTTPRequestHandler. Parse path. POST /jobs/: read Content-Length bytes, decode utf-8. Insert. Return 202.\n\nLet me write robust code.\n\nOne concern: the worker should run continuously and process jobs as they arrive. Poll every short interval. 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Use", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " http", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": ".server.Threading", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": "HTTP", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": "Server for", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " the", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " API.", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " Need", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " to handle concurrent", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " DB", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " access between", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " API", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " (", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": "writes on", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " POST,", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " reads on GET)", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " and worker (writes", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": "). SQLite", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " with", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " WAL mode and", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " busy", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": "_timeout", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " helps", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": ". Let", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " me set PR", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": "AGMA journal_mode", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": "=WAL", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " and busy_timeout=", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": "5000 in", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " both.\n\nLet", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " me write the code", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": ".\n\n", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": "For the", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " API, I", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": "'ll use Base", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": "HTTPRequestHandler. Parse", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " path", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": ".", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " POST /jobs/:", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " read", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " Content", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": "-Length bytes", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": ", decode", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " utf", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": "-8. Insert", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": ". Return", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " 202.\n\nLet", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " me write robust", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " code", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": ".\n\nOne", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " concern: the worker", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " should", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " run", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " continuously and", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " process", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " jobs", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " as they arrive", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": ". Poll", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " every", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " short", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " interval.", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " Keep", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " it lightweight", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": ".\n\nLet me write", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " the files.", "type": "reasoning.text" } ] }, { "type": "text", "text": "No flask available — I'll use the standard library. The schema and 3 queued jobs already exist. Plan:" }, { "type": "tool_use", "id": "call_1ee3b5fe23484f6391c5750f", "name": "TodoWrite", "input": { "todos": [ { "activeForm": "Writing api.py", "content": "Write /opt/job-queue/api.py (http.server, SQLite WAL)", "status": "in_progress" }, { "activeForm": "Writing worker.py", "content": "Write /opt/job-queue/worker.py (atomic exactly-once completion)", "status": "pending" }, { "activeForm": "Starting and verifying services", "content": "Reset failed units, start services, verify endpoints", "status": "pending" }, { "activeForm": "Verifying durability", "content": "Verify durability: restart worker, confirm jobs complete with attempts=1", "status": "pending" } ] } } ] }, { "role": "user", "content": [ { "type": "tool_result", "tool_use_id": "call_1ee3b5fe23484f6391c5750f", "content": "Added:\n + Write /opt/job-queue/api.py (http.server, SQLite WAL)\n + Write /opt/job-queue/worker.py (atomic exactly-once completion)\n + Reset failed units, start services, verify endpoints\n + Verify durability: restart worker, confirm jobs complete with attempts=1\n\nCurrent tasks:\n ◉ Write /opt/job-queue/api.py (http.server, SQLite WAL)\n ○ Write /opt/job-queue/worker.py (atomic exactly-once completion)\n ○ Reset failed units, start services, verify endpoints\n ○ Verify durability: restart worker, confirm jobs complete with attempts=1\n" } ] }, { "role": "assistant", "content": [ { "type": "tool_use", "id": "call_6ba08fdd49b842cfa654d7cf", "name": "Write", "input": { "content": "#!/usr/bin/env python3\n\"\"\"Durable job queue API.\n\nListens on port 8080. Uses the SQLite database at /var/lib/job-queue/jobs.sqlite3\nshared with the worker. All accepted jobs are persisted synchronously before\nthe API acknowledges the caller, so they survive worker restart and host reboot.\n\"\"\"\nimport json\nimport os\nimport re\nfrom http.server import BaseHTTPRequestHandler, ThreadingHTTPServer\n\nDB_PATH = \"/var/lib/job-queue/jobs.sqlite3\"\nPORT = 8080\nJOB_ID_RE = re.compile(r\"^/jobs/([^/]+)$\")\n\n\ndef connect():\n conn = __import__(\"sqlite3\").connect(DB_PATH, timeout=30, isolation_level=None)\n conn.execute(\"PRAGMA journal_mode=WAL\")\n conn.execute(\"PRAGMA synchronous=NORMAL\")\n conn.execute(\"PRAGMA busy_timeout=30000\")\n return conn\n\n\ndef ensure_schema():\n conn = connect()\n try:\n conn.execute(\n \"CREATE TABLE IF NOT EXISTS jobs (\"\n \"id TEXT PRIMARY KEY, payload TEXT NOT NULL, \"\n \"status TEXT NOT NULL, result TEXT, \"\n \"attempts INTEGER NOT NULL DEFAULT 0)\"\n )\n finally:\n conn.close()\n\n\nclass Handler(BaseHTTPRequestHandler):\n server_version = \"job-queue-api/1.0\"\n\n def log_message(self, fmt, *args): # silence default logging\n pass\n\n def _send(self, code, body=b\"\", content_type=\"text/plain; charset=utf-8\"):\n if isinstance(body, str):\n body = body.encode(\"utf-8\")\n self.send_response(code)\n self.send_header(\"Content-Type\", content_type)\n self.send_header(\"Content-Length\", str(len(body)))\n self.end_headers()\n if body:\n self.wfile.write(body)\n\n def do_GET(self):\n if self.path == \"/health\":\n self._send(200, \"ready\")\n return\n m = JOB_ID_RE.match(self.path)\n if not m:\n self._send(404, \"not found\")\n return\n job_id = m.group(1)\n conn = connect()\n try:\n row = conn.execute(\n \"SELECT id, payload, status, result, attempts FROM jobs WHERE id=?\",\n (job_id,),\n ).fetchone()\n finally:\n conn.close()\n if row is None:\n self._send(404, \"not found\")\n return\n payload = {\n \"id\": row[0],\n \"payload\": row[1],\n \"status\": row[2],\n \"result\": row[3],\n \"attempts\": row[4],\n }\n self._send(200, json.dumps(payload), \"application/json; charset=utf-8\")\n\n def do_POST(self):\n m = JOB_ID_RE.match(self.path)\n if not m:\n self._send(404, \"not found\")\n return\n job_id = m.group(1)\n length = int(self.headers.get(\"Content-Length\") or 0)\n raw = self.rfile.read(length) if length > 0 else b\"\"\n payload = raw.decode(\"utf-8\")\n # Persist synchronously before acknowledging. UPSERT so re-posting the\n # same id re-queues the job with fresh payload.\n conn = connect()\n try:\n conn.execute(\n \"INSERT INTO jobs(id, payload, status, result, attempts) \"\n \"VALUES(?, ?, 'queued', NULL, 0) \"\n \"ON CONFLICT(id) DO UPDATE SET \"\n \"payload=excluded.payload, status='queued', result=NULL, attempts=0\",\n (job_id, payload),\n )\n finally:\n conn.close()\n self._send(202, \"\")\n\n\ndef main():\n os.makedirs(os.path.dirname(DB_PATH), exist_ok=True)\n ensure_schema()\n server = ThreadingHTTPServer((\"0.0.0.0\", PORT), Handler)\n try:\n server.serve_forever()\n except KeyboardInterrupt:\n pass\n finally:\n server.server_close()\n\n\nif __name__ == \"__main__\":\n main()\n", "file_path": "/opt/job-queue/api.py" } } ] }, { "role": "user", "content": [ { "type": "tool_result", "tool_use_id": "call_6ba08fdd49b842cfa654d7cf", "content": "Successfully wrote to /opt/job-queue/api.py" } ] }, { "role": "assistant", "content": [ { "type": "tool_use", "id": "call_40609b6343e1487ca9bc9499", "name": "Write", "input": { "content": "#!/usr/bin/env python3\n\"\"\"Durable job queue worker.\n\nCompletes each queued job with result = \"processed:\" + payload using exactly\none attempt. Completion is performed inside a single immediate transaction:\nthe job moves directly from 'queued' to 'done' with attempts=1, so a crash can\nnever leave a job half-processed or double-processed. Re-running the worker\non an already-completed job is a no-op.\n\"\"\"\nimport sqlite3\nimport time\n\nDB_PATH = \"/var/lib/job-queue/jobs.sqlite3\"\nPOLL_INTERVAL = 0.2\n\n\ndef connect():\n conn = sqlite3.connect(DB_PATH, timeout=30, isolation_level=None)\n conn.execute(\"PRAGMA journal_mode=WAL\")\n conn.execute(\"PRAGMA synchronous=NORMAL\")\n conn.execute(\"PRAGMA busy_timeout=30000\")\n return conn\n\n\ndef process_one(conn):\n \"\"\"Atomically claim and complete one queued job. Returns True if a job was\n completed, False if the queue was empty.\"\"\"\n conn.execute(\"BEGIN IMMEDIATE\")\n try:\n row = conn.execute(\n \"SELECT id, payload FROM jobs WHERE status='queued' LIMIT 1\"\n ).fetchone()\n if row is None:\n conn.execute(\"ROLLBACK\")\n return False\n job_id, payload = row\n result = \"processed:\" + payload\n conn.execute(\n \"UPDATE jobs SET status='done', result=?, attempts=1 WHERE id=?\",\n (result, job_id),\n )\n conn.execute(\"COMMIT\")\n return True\n except Exception:\n conn.execute(\"ROLLBACK\")\n raise\n\n\ndef main():\n while True:\n try:\n conn = connect()\n try:\n while process_one(conn):\n pass\n finally:\n conn.close()\n except sqlite3.OperationalError as e:\n # Database is locked or unavailable; back off and retry.\n time.sleep(0.5)\n continue\n time.sleep(POLL_INTERVAL)\n\n\nif __name__ == \"__main__\":\n main()\n", "file_path": "/opt/job-queue/worker.py" } } ] }, { "role": "user", "content": [ { "type": "tool_result", "tool_use_id": "call_40609b6343e1487ca9bc9499", "content": "Successfully wrote to /opt/job-queue/worker.py" } ] }, { "role": "assistant", "content": [ { "type": "tool_use", "id": "call_181f490bf20a424180d1863b", "name": "TodoWrite", "input": { "todos": [ { "activeForm": "Writing api.py", "content": "Write /opt/job-queue/api.py (http.server, SQLite WAL)", "status": "completed" }, { "activeForm": "Writing worker.py", "content": "Write /opt/job-queue/worker.py (atomic exactly-once completion)", "status": "completed" }, { "activeForm": "Starting and verifying services", "content": "Reset failed units, start services, verify endpoints", "status": "in_progress" }, { "activeForm": "Verifying durability", "content": "Verify durability: restart worker, confirm jobs complete with attempts=1", "status": "pending" } ] } } ] }, { "role": "user", "content": [ { "type": "tool_result", "tool_use_id": "call_181f490bf20a424180d1863b", "content": "Started:\n > Starting and verifying services\nCompleted:\n ✓ Write /opt/job-queue/api.py (http.server, SQLite WAL)\n ✓ Write /opt/job-queue/worker.py (atomic exactly-once completion)\n\nCurrent tasks:\n ✓ Write /opt/job-queue/api.py (http.server, SQLite WAL)\n ✓ Write /opt/job-queue/worker.py (atomic exactly-once completion)\n ◉ Reset failed units, start services, verify endpoints\n ○ Verify durability: restart worker, confirm jobs complete with attempts=1\n" } ] }, { "role": "assistant", "content": [ { "type": "tool_use", "id": "call_9fe60055c85d41f19f321703", "name": "Bash", "input": { "command": "systemctl reset-failed queue-api.service queue-worker.service; systemctl daemon-reload; systemctl restart queue-api.service queue-worker.service; sleep 2; systemctl is-active queue-api.service queue-worker.service; echo \"=== seed state ===\"; sqlite3 /var/lib/job-queue/jobs.sqlite3 \"SELECT * FROM jobs;\"", "description": "Reset and restart services" } } ] }, { "role": "user", "content": [ { "type": "tool_result", "tool_use_id": "call_9fe60055c85d41f19f321703", "content": "active\nactive\n=== seed state ===\naccepted-alpha-7d3|alpha|done|processed:alpha|1\naccepted-beta-91e|beta|done|processed:beta|1\naccepted-gamma-c42|gamma|done|processed:gamma|1\n" } ] }, { "role": "assistant", "content": [ { "type": "text", "text": "All three pre-existing jobs completed with attempts=1. Now verify the endpoints and durability." }, { "type": "tool_use", "id": "call_304d1b9b8055459db3f062a3", "name": "Bash", "input": { "command": "echo \"=== /health ===\"; curl -s -w \"\\nHTTP %{http_code}\\n\" http://localhost:8080/health; echo \"=== GET existing job ===\"; curl -s http://localhost:8080/jobs/accepted-alpha-7d3; echo; echo \"=== POST new job ===\"; curl -s -w \"\\nHTTP %{http_code}\\n\" -X POST --data-binary 'héllo wörld' http://localhost:8080/jobs/job-new-123; sleep 1; echo \"=== GET new job (after worker) ===\"; curl -s http://localhost:8080/jobs/job-new-123; echo", "description": "Verify health, GET, POST, worker completion" } } ] }, { "role": "user", "content": [ { "type": "tool_result", "tool_use_id": "call_304d1b9b8055459db3f062a3", "content": "=== /health ===\nready\nHTTP 200\n=== GET existing job ===\n{\"id\": \"accepted-alpha-7d3\", \"payload\": \"alpha\", \"status\": \"done\", \"result\": \"processed:alpha\", \"attempts\": 1}\n=== POST new job ===\n\nHTTP 202\n=== GET new job (after worker) ===\n{\"id\": \"job-new-123\", \"payload\": \"h\\u00e9llo w\\u00f6rld\", \"status\": \"done\", \"result\": \"processed:h\\u00e9llo w\\u00f6rld\", \"attempts\": 1}\n" } ] }, { "role": "assistant", "content": [ { "type": "text", "text": "Now durability: restart worker mid-queue, and reboot-simulate by restarting both services plus seed." }, { "type": "tool_use", "id": "call_cd1ab81af61f4abf91f27ea6", "name": "Bash", "input": { "command": "# Submit a batch of jobs, then immediately restart the worker to prove restart-survival\nfor i in $(seq 1 20); do curl -s -X POST --data-binary \"payload-$i\" http://localhost:8080/jobs/burst-$i >/dev/null; done\nsystemctl restart queue-worker.service\nsleep 2\necho \"=== burst jobs after worker restart ===\"\nsqlite3 /var/lib/job-queue/jobs.sqlite3 \"SELECT status, COUNT(*) FROM jobs WHERE id LIKE 'burst-%' GROUP BY status;\"\necho \"=== all done, attempts check ===\"\nsqlite3 /var/lib/job-queue/jobs.sqlite3 \"SELECT COUNT(*) AS done, MIN(attempts), MAX(attempts) FROM jobs WHERE id LIKE 'burst-%' AND status='done';\"\necho \"=== verify result correctness ===\"\nsqlite3 /var/lib/job-queue/jobs.sqlite3 \"SELECT id, result FROM jobs WHERE id LIKE 'burst-%' LIMIT 3;\"", "description": "Burst + worker restart durability test" } } ] }, { "role": "user", "content": [ { "type": "tool_result", "tool_use_id": "call_cd1ab81af61f4abf91f27ea6", "content": "=== burst jobs after worker restart ===\ndone|20\n=== all done, attempts check ===\n20|1|1\n=== verify result correctness ===\nburst-1|processed:payload-1\nburst-2|processed:payload-2\nburst-3|processed:payload-3\n" } ] }, { "role": "assistant", "content": [ { "type": "reasoning", "text": "All 20 burst jobs completed with exactly attempts=1 even after worker restart. Now let me test full reboot simulation: restart everything including seed (which is the dependency that runs first on boot).", "details": [ { "format": "unknown", "index": 0, "text": "All", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " 20 burst", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " jobs", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " completed with", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " exactly attempts", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": "=1 even", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " after worker restart.", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " Now let me test", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " full", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " reboot simulation", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": ": restart everything", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " including", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " seed (", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": "which is the", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " dependency", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " that", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " runs first", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " on", "type": "reasoning.text" }, { "format": "unknown", "index": 0, "text": " boot).", "type": "reasoning.text" } ] }, { "type": "text", "text": "All 20 completed with attempts=1 despite worker restart. Now simulate a full host-boot sequence (seed → api → worker) by restarting the whole chain." }, { "type": "tool_use", "id": "call_b08cd47c9cb84800a6c57a8a", "name": "Bash", "input": { "command": "# Simulate reboot ordering: stop both, re-run seed, then start both (as on boot)\nsystemctl stop queue-api.service queue-worker.service\nsystemctl restart queue-seed.service\nsleep 1\nsystemctl start queue-api.service queue-worker.service\nsleep 2\necho \"=== active state ===\"; systemctl is-active queue-api queue-worker queue-seed\necho \"=== seed jobs intact ===\"; sqlite3 /var/lib/job-queue/jobs.sqlite3 \"SELECT id,status,attempts FROM jobs WHERE id LIKE 'accepted-%';\"\necho \"=== health after simulated reboot ===\"; curl -s -w \" HTTP %{http_code}\\n\" http://localhost:8080/health\necho \"=== submit post-reboot job ===\"; curl -s -X POST --data-binary 'reboot-test' http://localhost:8080/jobs/post-reboot-1 -w \" HTTP %{http_code}\\n\"; sleep 1\ncurl -s http://localhost:8080/jobs/post-reboot-1; echo\necho \"=== final summary ===\"; sqlite3 /var/lib/job-queue/jobs.sqlite3 \"SELECT status, COUNT(*), MIN(attempts), MAX(attempts) FROM jobs GROUP BY status;\"", "description": "Full reboot-ordering simulation" } } ] }, { "role": "user", "content": [ { "type": "tool_result", "tool_use_id": "call_b08cd47c9cb84800a6c57a8a", "content": "=== active state ===\nactive\nactive\nactive\n=== seed jobs intact ===\naccepted-alpha-7d3|done|1\naccepted-beta-91e|done|1\naccepted-gamma-c42|done|1\n=== health after simulated reboot ===\nready HTTP 200\n=== submit post-reboot job ===\n HTTP 202\n{\"id\": \"post-reboot-1\", \"payload\": \"reboot-test\", \"status\": \"done\", \"result\": \"processed:reboot-test\", \"attempts\": 1}\n=== final summary ===\ndone|25|1|1\n" } ] }, { "role": "assistant", "content": [ { "type": "tool_use", "id": "call_4b8a1b3c22194c9e8cef517c", "name": "Bash", "input": { "command": "systemctl is-enabled queue-api queue-worker queue-seed; echo \"=== api log tail ===\"; journalctl -u queue-api.service -n 5 --no-pager 2>&1; echo \"=== worker log tail ===\"; journalctl -u queue-worker.service -n 5 --no-pager 2>&1", "description": "Confirm units enabled for auto-start on boot" } } ] }, { "role": "user", "content": [ { "type": "tool_result", "tool_use_id": "call_4b8a1b3c22194c9e8cef517c", "content": "enabled\nenabled\nenabled\n=== api log tail ===\nAug 15 02:44:39 queue-three systemd[1]: Stopping Agent-built durable queue API slot...\nAug 15 02:44:39 queue-three systemd[1]: queue-api.service: Deactivated successfully.\nAug 15 02:44:39 queue-three systemd[1]: Stopped Agent-built durable queue API slot.\nAug 15 02:44:39 queue-three systemd[1]: queue-api.service: Consumed 216ms CPU time over 21.558s wall clock time, 10.8M memory peak, 364K written to disk, 27.9K incoming IP traffic, 35K outgoing IP traffic.\nAug 15 02:44:40 queue-three systemd[1]: Started Agent-built durable queue API slot.\n=== worker log tail ===\nAug 15 02:44:31 queue-three systemd[1]: Started Agent-built durable queue worker slot.\nAug 15 02:44:39 queue-three systemd[1]: Stopping Agent-built durable queue worker slot...\nAug 15 02:44:39 queue-three systemd[1]: queue-worker.service: Deactivated successfully.\nAug 15 02:44:39 queue-three systemd[1]: Stopped Agent-built durable queue worker slot.\nAug 15 02:44:40 queue-three systemd[1]: Started Agent-built durable queue worker slot.\n" } ] }, { "role": "assistant", "content": [ { "type": "text", "text": "All three units are `enabled` (auto-start on boot). Services are running cleanly." }, { "type": "tool_use", "id": "call_9fe8608dbbee492497589e77", "name": "TodoWrite", "input": { "todos": [ { "activeForm": "Writing api.py", "content": "Write /opt/job-queue/api.py (http.server, SQLite WAL)", "status": "completed" }, { "activeForm": "Writing worker.py", "content": "Write /opt/job-queue/worker.py (atomic exactly-once completion)", "status": "completed" }, { "activeForm": "Starting and verifying services", "content": "Reset failed units, start services, verify endpoints", "status": "completed" }, { "activeForm": "Verifying durability", "content": "Verify durability: restart worker, confirm jobs complete with attempts=1", "status": "completed" } ] } } ] }, { "role": "user", "content": [ { "type": "tool_result", "tool_use_id": "call_9fe8608dbbee492497589e77", "content": "Completed:\n ✓ Reset failed units, start services, verify endpoints\n ✓ Verify durability: restart worker, confirm jobs complete with attempts=1\n\nAll tasks completed. List cleared." } ] }, { "role": "assistant", "content": [ { "type": "text", "text": "The durable job queue is deployed, verified, and running.\n\n## What was built\n\n**`/opt/job-queue/api.py`** — stdlib `http.server` (no Flask available), port 8080:\n- `GET /health` → `200` with body `ready`\n- `POST /jobs/` → accepts UTF-8 body, persists synchronously via `INSERT … ON CONFLICT DO UPDATE` (re-posts re-queue), returns `202`\n- `GET /jobs/` → JSON with `id`, `payload`, `status`, `result`, integer `attempts`\n\n**`/opt/job-queue/worker.py`** — polls the DB and completes jobs:\n- Each job transitions `queued → done` with `result = \"processed:\" + payload` and `attempts = 1` inside a **single `BEGIN IMMEDIATE` transaction**. No intermediate \"processing\" state exists, so a crash can never leave a job half-done or cause double-processing. Re-running on a completed job is a no-op.\n- WAL mode + `busy_timeout=30000` for safe concurrent access with the API.\n\n## Verification results\n\n| Check | Result |\n|---|---|\n| `/health` | `ready`, `200` |\n| 3 pre-existing `accepted-*` jobs | completed, `attempts=1`, correct results |\n| `POST` new job (incl. UTF-8) | `202`, then `done` with `processed:…` |\n| Burst of 20 jobs + worker restart mid-flight | all 20 `done`, `attempts` min/max = 1/1 |\n| Full reboot simulation (stop → seed → api → worker) | all 3 units `active`; seed jobs intact; new post-reboot job completed |\n| Unit enablement | `queue-api`, `queue-worker`, `queue-seed` all `enabled` → auto-start on boot |\n\nFinal DB state: 25 jobs, all `done`, every one with exactly `attempts=1`. Both services return on their own after reboot via the existing enabled systemd units." } ] } ], "tool_trace": [ { "id": "5e48dda3-02a9-445a-b429-4da07ead3a8f", "name": "Bash", "input": { "command": "ls -la /opt/job-queue/ 2>&1; echo \"---\"; ls -la /var/lib/job-queue/ 2>&1; echo \"---\"; systemctl list-unit-files 2>/dev/null | grep -i queue; echo \"---\"; systemctl status queue-api.service queue-worker.service 2>&1 | head -40", "description": "Inspect existing job-queue state" }, "output": "ls: cannot access '/opt/job-queue/': No such file or directory\n---\ntotal 20\ndrwxr-xr-x 2 root root 4096 Aug 15 02:43 .\ndrwxr-xr-x 9 root root 4096 Aug 15 02:43 ..\n-rw-r--r-- 1 root root 12288 Aug 15 02:43 jobs.sqlite3\n---\ndev-mqueue.mount enabled ignored\nqueue-api.service enabled ignored\nqueue-seed.service enabled ignored\nqueue-worker.service enabled ignored\n---\n× queue-api.service - Agent-built durable queue API slot\n Loaded: loaded (/etc/systemd/system/queue-api.service; enabled; preset: ignored)\n Active: failed (Result: start-limit-hit) since Sat 2026-08-15 02:43:24 UTC; 6s ago\n Duration: 247ms\n Invocation: 32aaf46928e7498da8da445f6b43a169\n Process: 671 ExecStart=/nix/store/3n4qphl9s728sz8frmpqqrv9b1m87g68-python3-3.14.7/bin/python /opt/job-queue/api.py (code=exited, status=2)\n Main PID: 671 (code=exited, status=2)\n IP: 0B in, 0B out\n IO: 0B read, 0B written\n Mem peak: 4.1M\n CPU: 48ms\n\nAug 15 02:43:24 queue-three systemd[1]: queue-api.service: Scheduled restart job, restart counter is at 5.\nAug 15 02:43:24 queue-three systemd[1]: queue-api.service: Start request repeated too quickly.\nAug 15 02:43:24 queue-three systemd[1]: queue-api.service: Failed with result 'start-limit-hit'.\nAug 15 02:43:24 queue-three systemd[1]: Failed to start Agent-built durable queue API slot.\n\n× queue-worker.service - Agent-built durable queue worker slot\n Loaded: loaded (/etc/systemd/system/queue-worker.service; enabled; preset: ignored)\n Active: failed (Result: start-limit-hit) since Sat 2026-08-15 02:43:24 UTC; 6s ago\n Duration: 238ms\n Invocation: 90cd951472b94b3b8cdefcc6a6c06b6a\n Process: 672 ExecStart=/nix/store/3n4qphl9s728sz8frmpqqrv9b1m87g68-python3-3.14.7/bin/python /opt/job-queue/worker.py (code=exited, status=2)\n Main PID: 672 (code=exited, status=2)\n IP: 0B in, 0B out\n IO: 0B read, 0B written\n Mem peak: 4.1M\n CPU: 67ms\n\nAug 15 02:43:24 queue-three systemd[1]: queue-worker.service: Scheduled restart job, restart counter is at 5.\nAug 15 02:43:24 queue-three systemd[1]: queue-worker.service: Start request repeated too quickly.\nAug 15 02:43:24 queue-three systemd[1]: queue-worker.service: Failed with result 'start-limit-hit'.\nAug 15 02:43:24 queue-three systemd[1]: Failed to start Agent-built durable queue worker slot.\n", "is_error": false, "read_only": false, "started_after_ms": 1291, "duration_ms": 5702 }, { "id": "314c0a53-b0b5-4316-bdb2-c45ce7a793b4", "name": "Bash", "input": { "command": "cat /etc/systemd/system/queue-api.service; echo \"===\"; cat /etc/systemd/system/queue-worker.service; echo \"===\"; cat /etc/systemd/system/queue-seed.service; echo \"===\"; which python3; python3 --version; echo \"===\"; cat /etc/systemd/system/queue-seed.service 2>/dev/null | head; echo \"=== sqlite schema ===\"; sqlite3 /var/lib/job-queue/jobs.sqlite3 \".schema\" 2>&1; echo \"=== rows ===\"; sqlite3 /var/lib/job-queue/jobs.sqlite3 \"SELECT * FROM jobs;\" 2>&1 | head -20", "description": "Inspect units, python, db schema" }, "output": "[Unit]\nAfter=network.target queue-seed.service\nDescription=Agent-built durable queue API slot\nRequires=queue-seed.service\n\n[Service]\nEnvironment=\"LOCALE_ARCHIVE=/nix/store/c59mcax29xrwyfdqs308wkmn2srnmzkn-glibc-locales-2.42-67/lib/locale/locale-archive\"\nEnvironment=\"PATH=/nix/store/97d5ygrvqj55f4nx1x34wfdcc7qn11c0-coreutils-9.11/bin:/nix/store/ibg16grw5is7i7ilnflc5xmj6fwksqkl-findutils-4.11.0/bin:/nix/store/4dgym2zhac9vy0vrih4gsplh0wpfl13m-gnugrep-3.12/bin:/nix/store/rxd8p6g4k4s0sx4q1szmzvp9rsmhmfys-gnused-4.10/bin:/nix/store/mc901k2s1n3v1disrj0356l7lwz7l6vg-systemd-261.1/bin:/nix/store/97d5ygrvqj55f4nx1x34wfdcc7qn11c0-coreutils-9.11/sbin:/nix/store/ibg16grw5is7i7ilnflc5xmj6fwksqkl-findutils-4.11.0/sbin:/nix/store/4dgym2zhac9vy0vrih4gsplh0wpfl13m-gnugrep-3.12/sbin:/nix/store/rxd8p6g4k4s0sx4q1szmzvp9rsmhmfys-gnused-4.10/sbin:/nix/store/mc901k2s1n3v1disrj0356l7lwz7l6vg-systemd-261.1/sbin\"\nEnvironment=\"TZDIR=/nix/store/vlgjd2179ahfh509p1aid8fl22bw8ri3-tzdata-2026c/share/zoneinfo\"\nExecStart=/nix/store/3n4qphl9s728sz8frmpqqrv9b1m87g68-python3-3.14.7/bin/python /opt/job-queue/api.py\nRestart=always\nRestartSec=1\n\n[Install]\nWantedBy=multi-user.target\n===\n[Unit]\nAfter=queue-seed.service\nDescription=Agent-built durable queue worker slot\nRequires=queue-seed.service\n\n[Service]\nEnvironment=\"LOCALE_ARCHIVE=/nix/store/c59mcax29xrwyfdqs308wkmn2srnmzkn-glibc-locales-2.42-67/lib/locale/locale-archive\"\nEnvironment=\"PATH=/nix/store/97d5ygrvqj55f4nx1x34wfdcc7qn11c0-coreutils-9.11/bin:/nix/store/ibg16grw5is7i7ilnflc5xmj6fwksqkl-findutils-4.11.0/bin:/nix/store/4dgym2zhac9vy0vrih4gsplh0wpfl13m-gnugrep-3.12/bin:/nix/store/rxd8p6g4k4s0sx4q1szmzvp9rsmhmfys-gnused-4.10/bin:/nix/store/mc901k2s1n3v1disrj0356l7lwz7l6vg-systemd-261.1/bin:/nix/store/97d5ygrvqj55f4nx1x34wfdcc7qn11c0-coreutils-9.11/sbin:/nix/store/ibg16grw5is7i7ilnflc5xmj6fwksqkl-findutils-4.11.0/sbin:/nix/store/4dgym2zhac9vy0vrih4gsplh0wpfl13m-gnugrep-3.12/sbin:/nix/store/rxd8p6g4k4s0sx4q1szmzvp9rsmhmfys-gnused-4.10/sbin:/nix/store/mc901k2s1n3v1disrj0356l7lwz7l6vg-systemd-261.1/sbin\"\nEnvironment=\"TZDIR=/nix/store/vlgjd2179ahfh509p1aid8fl22bw8ri3-tzdata-2026c/share/zoneinfo\"\nExecStart=/nix/store/3n4qphl9s728sz8frmpqqrv9b1m87g68-python3-3.14.7/bin/python /opt/job-queue/worker.py\nRestart=always\nRestartSec=1\n\n[Install]\nWantedBy=multi-user.target\n===\n[Unit]\nBefore=queue-api.service queue-worker.service\nDescription=Seed opaque jobs accepted before the deployment\n\n[Service]\nEnvironment=\"LOCALE_ARCHIVE=/nix/store/c59mcax29xrwyfdqs308wkmn2srnmzkn-glibc-locales-2.42-67/lib/locale/locale-archive\"\nEnvironment=\"PATH=/nix/store/97d5ygrvqj55f4nx1x34wfdcc7qn11c0-coreutils-9.11/bin:/nix/store/ibg16grw5is7i7ilnflc5xmj6fwksqkl-findutils-4.11.0/bin:/nix/store/4dgym2zhac9vy0vrih4gsplh0wpfl13m-gnugrep-3.12/bin:/nix/store/rxd8p6g4k4s0sx4q1szmzvp9rsmhmfys-gnused-4.10/bin:/nix/store/mc901k2s1n3v1disrj0356l7lwz7l6vg-systemd-261.1/bin:/nix/store/97d5ygrvqj55f4nx1x34wfdcc7qn11c0-coreutils-9.11/sbin:/nix/store/ibg16grw5is7i7ilnflc5xmj6fwksqkl-findutils-4.11.0/sbin:/nix/store/4dgym2zhac9vy0vrih4gsplh0wpfl13m-gnugrep-3.12/sbin:/nix/store/rxd8p6g4k4s0sx4q1szmzvp9rsmhmfys-gnused-4.10/sbin:/nix/store/mc901k2s1n3v1disrj0356l7lwz7l6vg-systemd-261.1/sbin\"\nEnvironment=\"TZDIR=/nix/store/vlgjd2179ahfh509p1aid8fl22bw8ri3-tzdata-2026c/share/zoneinfo\"\nExecStart=/nix/store/2dfn4ylvf2r7j47aqms6mn63pnk0nj5h-unit-script-queue-seed-start/bin/queue-seed-start \nRemainAfterExit=true\nType=oneshot\n\n[Install]\nWantedBy=multi-user.target\n===\n/run/current-system/sw/bin/python3\nPython 3.14.7\n===\n[Unit]\nBefore=queue-api.service queue-worker.service\nDescription=Seed opaque jobs accepted before the deployment\n\n[Service]\nEnvironment=\"LOCALE_ARCHIVE=/nix/store/c59mcax29xrwyfdqs308wkmn2srnmzkn-glibc-locales-2.42-67/lib/locale/locale-archive\"\nEnvironment=\"PATH=/nix/store/97d5ygrvqj55f4nx1x34wfdcc7qn11c0-coreutils-9.11/bin:/nix/store/ibg16grw5is7i7ilnflc5xmj6fwksqkl-findutils-4.11.0/bin:/nix/store/4dgym2zhac9vy0vrih4gsplh0wpfl13m-gnugrep-3.12/bin:/nix/store/rxd8p6g4k4s0sx4q1szmzvp9rsmhmfys-gnused-4.10/bin:/nix/store/mc901k2s1n3v1disrj0356l7lwz7l6vg-systemd-261.1/bin:/nix/store/97d5ygrvqj55f4nx1x34wfdcc7qn11c0-coreutils-9.11/sbin:/nix/store/ibg16grw5is7i7ilnflc5xmj6fwksqkl-findutils-4.11.0/sbin:/nix/store/4dgym2zhac9vy0vrih4gsplh0wpfl13m-gnugrep-3.12/sbin:/nix/store/rxd8p6g4k4s0sx4q1szmzvp9rsmhmfys-gnused-4.10/sbin:/nix/store/mc901k2s1n3v1disrj0356l7lwz7l6vg-systemd-261.1/sbin\"\nEnvironment=\"TZDIR=/nix/store/vlgjd2179ahfh509p1aid8fl22bw8ri3-tzdata-2026c/share/zoneinfo\"\nExecStart=/nix/store/2dfn4ylvf2r7j47aqms6mn63pnk0nj5h-unit-script-queue-seed-start/bin/queue-seed-start \nRemainAfterExit=true\n=== sqlite schema ===\nCREATE TABLE jobs (id TEXT PRIMARY KEY, payload TEXT NOT NULL, status TEXT NOT NULL, result TEXT, attempts INTEGER NOT NULL DEFAULT 0);\n=== rows ===\naccepted-alpha-7d3|alpha|queued||0\naccepted-beta-91e|beta|queued||0\naccepted-gamma-c42|gamma|queued||0\n", "is_error": false, "read_only": false, "started_after_ms": 8978, "duration_ms": 104 }, { "id": "389e3405-ea98-438f-b46c-bd8116852d5a", "name": "Bash", "input": { "command": "cat /nix/store/2dfn4ylvf2r7j47aqms6mn63pnk0nj5h-unit-script-queue-seed-start/bin/queue-seed-start 2>&1 | head -60; echo \"=== which sqlite3 ===\"; which sqlite3; echo \"=== python modules ===\"; python3 -c \"import sqlite3; print('sqlite3 ok')\"; python3 -c \"import flask\" 2>&1; python3 -c \"import http.server; print('http.server ok')\"", "description": "Inspect seed script and python modules" }, "output": "#!/nix/store/byi2zpy2bgcf3dr6y0l8m50rmjj8z7q1-bash-5.3p15/bin/bash\nset -e\n\ninstall -d -m 0755 /var/lib/job-queue\n/nix/store/3n4qphl9s728sz8frmpqqrv9b1m87g68-python3-3.14.7/bin/python - <<'PY'\nimport sqlite3\ndb = sqlite3.connect('/var/lib/job-queue/jobs.sqlite3')\ndb.execute('CREATE TABLE IF NOT EXISTS jobs (id TEXT PRIMARY KEY, payload TEXT NOT NULL, status TEXT NOT NULL, result TEXT, attempts INTEGER NOT NULL DEFAULT 0)')\nfor job, payload in [('accepted-alpha-7d3', 'alpha'), ('accepted-beta-91e', 'beta'), ('accepted-gamma-c42', 'gamma')]:\n db.execute('INSERT OR IGNORE INTO jobs(id,payload,status,result,attempts) VALUES(?,?,\\\"queued\\\",NULL,0)', (job,payload))\ndb.commit()\nPY\n\n\n=== which sqlite3 ===\n/run/current-system/sw/bin/sqlite3\n=== python modules ===\nsqlite3 ok\nTraceback (most recent call last):\n File \"\", line 1, in \n import flask\nModuleNotFoundError: No module named 'flask'\nhttp.server ok\n", "is_error": false, "read_only": false, "started_after_ms": 11013, "duration_ms": 528 }, { "id": "call_1ee3b5fe23484f6391c5750f", "name": "TodoWrite", "input": { "todos": [ { "activeForm": "Writing api.py", "content": "Write /opt/job-queue/api.py (http.server, SQLite WAL)", "status": "in_progress" }, { "activeForm": "Writing worker.py", "content": "Write /opt/job-queue/worker.py (atomic exactly-once completion)", "status": "pending" }, { "activeForm": "Starting and verifying services", "content": "Reset failed units, start services, verify endpoints", "status": "pending" }, { "activeForm": "Verifying durability", "content": "Verify durability: restart worker, confirm jobs complete with attempts=1", "status": "pending" } ] }, "output": "Added:\n + Write /opt/job-queue/api.py (http.server, SQLite WAL)\n + Write /opt/job-queue/worker.py (atomic exactly-once completion)\n + Reset failed units, start services, verify endpoints\n + Verify durability: restart worker, confirm jobs complete with attempts=1\n\nCurrent tasks:\n ◉ Write /opt/job-queue/api.py (http.server, SQLite WAL)\n ○ Write /opt/job-queue/worker.py (atomic exactly-once completion)\n ○ Reset failed units, start services, verify endpoints\n ○ Verify durability: restart worker, confirm jobs complete with attempts=1\n", "is_error": false, "read_only": true, "started_after_ms": 29957, "duration_ms": 0 }, { "id": "call_6ba08fdd49b842cfa654d7cf", "name": "Write", "input": { "content": "#!/usr/bin/env python3\n\"\"\"Durable job queue API.\n\nListens on port 8080. Uses the SQLite database at /var/lib/job-queue/jobs.sqlite3\nshared with the worker. All accepted jobs are persisted synchronously before\nthe API acknowledges the caller, so they survive worker restart and host reboot.\n\"\"\"\nimport json\nimport os\nimport re\nfrom http.server import BaseHTTPRequestHandler, ThreadingHTTPServer\n\nDB_PATH = \"/var/lib/job-queue/jobs.sqlite3\"\nPORT = 8080\nJOB_ID_RE = re.compile(r\"^/jobs/([^/]+)$\")\n\n\ndef connect():\n conn = __import__(\"sqlite3\").connect(DB_PATH, timeout=30, isolation_level=None)\n conn.execute(\"PRAGMA journal_mode=WAL\")\n conn.execute(\"PRAGMA synchronous=NORMAL\")\n conn.execute(\"PRAGMA busy_timeout=30000\")\n return conn\n\n\ndef ensure_schema():\n conn = connect()\n try:\n conn.execute(\n \"CREATE TABLE IF NOT EXISTS jobs (\"\n \"id TEXT PRIMARY KEY, payload TEXT NOT NULL, \"\n \"status TEXT NOT NULL, result TEXT, \"\n \"attempts INTEGER NOT NULL DEFAULT 0)\"\n )\n finally:\n conn.close()\n\n\nclass Handler(BaseHTTPRequestHandler):\n server_version = \"job-queue-api/1.0\"\n\n def log_message(self, fmt, *args): # silence default logging\n pass\n\n def _send(self, code, body=b\"\", content_type=\"text/plain; charset=utf-8\"):\n if isinstance(body, str):\n body = body.encode(\"utf-8\")\n self.send_response(code)\n self.send_header(\"Content-Type\", content_type)\n self.send_header(\"Content-Length\", str(len(body)))\n self.end_headers()\n if body:\n self.wfile.write(body)\n\n def do_GET(self):\n if self.path == \"/health\":\n self._send(200, \"ready\")\n return\n m = JOB_ID_RE.match(self.path)\n if not m:\n self._send(404, \"not found\")\n return\n job_id = m.group(1)\n conn = connect()\n try:\n row = conn.execute(\n \"SELECT id, payload, status, result, attempts FROM jobs WHERE id=?\",\n (job_id,),\n ).fetchone()\n finally:\n conn.close()\n if row is None:\n self._send(404, \"not found\")\n return\n payload = {\n \"id\": row[0],\n \"payload\": row[1],\n \"status\": row[2],\n \"result\": row[3],\n \"attempts\": row[4],\n }\n self._send(200, json.dumps(payload), \"application/json; charset=utf-8\")\n\n def do_POST(self):\n m = JOB_ID_RE.match(self.path)\n if not m:\n self._send(404, \"not found\")\n return\n job_id = m.group(1)\n length = int(self.headers.get(\"Content-Length\") or 0)\n raw = self.rfile.read(length) if length > 0 else b\"\"\n payload = raw.decode(\"utf-8\")\n # Persist synchronously before acknowledging. UPSERT so re-posting the\n # same id re-queues the job with fresh payload.\n conn = connect()\n try:\n conn.execute(\n \"INSERT INTO jobs(id, payload, status, result, attempts) \"\n \"VALUES(?, ?, 'queued', NULL, 0) \"\n \"ON CONFLICT(id) DO UPDATE SET \"\n \"payload=excluded.payload, status='queued', result=NULL, attempts=0\",\n (job_id, payload),\n )\n finally:\n conn.close()\n self._send(202, \"\")\n\n\ndef main():\n os.makedirs(os.path.dirname(DB_PATH), exist_ok=True)\n ensure_schema()\n server = ThreadingHTTPServer((\"0.0.0.0\", PORT), Handler)\n try:\n server.serve_forever()\n except KeyboardInterrupt:\n pass\n finally:\n server.server_close()\n\n\nif __name__ == \"__main__\":\n main()\n", "file_path": "/opt/job-queue/api.py" }, "output": "Successfully wrote to /opt/job-queue/api.py", "is_error": false, "read_only": false, "started_after_ms": 40991, "duration_ms": 0 }, { "id": "call_40609b6343e1487ca9bc9499", "name": "Write", "input": { "content": "#!/usr/bin/env python3\n\"\"\"Durable job queue worker.\n\nCompletes each queued job with result = \"processed:\" + payload using exactly\none attempt. Completion is performed inside a single immediate transaction:\nthe job moves directly from 'queued' to 'done' with attempts=1, so a crash can\nnever leave a job half-processed or double-processed. Re-running the worker\non an already-completed job is a no-op.\n\"\"\"\nimport sqlite3\nimport time\n\nDB_PATH = \"/var/lib/job-queue/jobs.sqlite3\"\nPOLL_INTERVAL = 0.2\n\n\ndef connect():\n conn = sqlite3.connect(DB_PATH, timeout=30, isolation_level=None)\n conn.execute(\"PRAGMA journal_mode=WAL\")\n conn.execute(\"PRAGMA synchronous=NORMAL\")\n conn.execute(\"PRAGMA busy_timeout=30000\")\n return conn\n\n\ndef process_one(conn):\n \"\"\"Atomically claim and complete one queued job. Returns True if a job was\n completed, False if the queue was empty.\"\"\"\n conn.execute(\"BEGIN IMMEDIATE\")\n try:\n row = conn.execute(\n \"SELECT id, payload FROM jobs WHERE status='queued' LIMIT 1\"\n ).fetchone()\n if row is None:\n conn.execute(\"ROLLBACK\")\n return False\n job_id, payload = row\n result = \"processed:\" + payload\n conn.execute(\n \"UPDATE jobs SET status='done', result=?, attempts=1 WHERE id=?\",\n (result, job_id),\n )\n conn.execute(\"COMMIT\")\n return True\n except Exception:\n conn.execute(\"ROLLBACK\")\n raise\n\n\ndef main():\n while True:\n try:\n conn = connect()\n try:\n while process_one(conn):\n pass\n finally:\n conn.close()\n except sqlite3.OperationalError as e:\n # Database is locked or unavailable; back off and retry.\n time.sleep(0.5)\n continue\n time.sleep(POLL_INTERVAL)\n\n\nif __name__ == \"__main__\":\n main()\n", "file_path": "/opt/job-queue/worker.py" }, "output": "Successfully wrote to /opt/job-queue/worker.py", "is_error": false, "read_only": false, "started_after_ms": 47556, "duration_ms": 0 }, { "id": "call_181f490bf20a424180d1863b", "name": "TodoWrite", "input": { "todos": [ { "activeForm": "Writing api.py", "content": "Write /opt/job-queue/api.py (http.server, SQLite WAL)", "status": "completed" }, { "activeForm": "Writing worker.py", "content": "Write /opt/job-queue/worker.py (atomic exactly-once completion)", "status": "completed" }, { "activeForm": "Starting and verifying services", "content": "Reset failed units, start services, verify endpoints", "status": "in_progress" }, { "activeForm": "Verifying durability", "content": "Verify durability: restart worker, confirm jobs complete with attempts=1", "status": "pending" } ] }, "output": "Started:\n > Starting and verifying services\nCompleted:\n ✓ Write /opt/job-queue/api.py (http.server, SQLite WAL)\n ✓ Write /opt/job-queue/worker.py (atomic exactly-once completion)\n\nCurrent tasks:\n ✓ Write /opt/job-queue/api.py (http.server, SQLite WAL)\n ✓ Write /opt/job-queue/worker.py (atomic exactly-once completion)\n ◉ Reset failed units, start services, verify endpoints\n ○ Verify durability: restart worker, confirm jobs complete with attempts=1\n", "is_error": false, "read_only": true, "started_after_ms": 50280, "duration_ms": 0 }, { "id": "call_9fe60055c85d41f19f321703", "name": "Bash", "input": { "command": "systemctl reset-failed queue-api.service queue-worker.service; systemctl daemon-reload; systemctl restart queue-api.service queue-worker.service; sleep 2; systemctl is-active queue-api.service queue-worker.service; echo \"=== seed state ===\"; sqlite3 /var/lib/job-queue/jobs.sqlite3 \"SELECT * FROM jobs;\"", "description": "Reset and restart services" }, "output": "active\nactive\n=== seed state ===\naccepted-alpha-7d3|alpha|done|processed:alpha|1\naccepted-beta-91e|beta|done|processed:beta|1\naccepted-gamma-c42|gamma|done|processed:gamma|1\n", "is_error": false, "read_only": false, "started_after_ms": 52797, "duration_ms": 2625 }, { "id": "call_304d1b9b8055459db3f062a3", "name": "Bash", "input": { "command": "echo \"=== /health ===\"; curl -s -w \"\\nHTTP %{http_code}\\n\" http://localhost:8080/health; echo \"=== GET existing job ===\"; curl -s http://localhost:8080/jobs/accepted-alpha-7d3; echo; echo \"=== POST new job ===\"; curl -s -w \"\\nHTTP %{http_code}\\n\" -X POST --data-binary 'héllo wörld' http://localhost:8080/jobs/job-new-123; sleep 1; echo \"=== GET new job (after worker) ===\"; curl -s http://localhost:8080/jobs/job-new-123; echo", "description": "Verify health, GET, POST, worker completion" }, "output": "=== /health ===\nready\nHTTP 200\n=== GET existing job ===\n{\"id\": \"accepted-alpha-7d3\", \"payload\": \"alpha\", \"status\": \"done\", \"result\": \"processed:alpha\", \"attempts\": 1}\n=== POST new job ===\n\nHTTP 202\n=== GET new job (after worker) ===\n{\"id\": \"job-new-123\", \"payload\": \"h\\u00e9llo w\\u00f6rld\", \"status\": \"done\", \"result\": \"processed:h\\u00e9llo w\\u00f6rld\", \"attempts\": 1}\n", "is_error": false, "read_only": false, "started_after_ms": 59533, "duration_ms": 1142 }, { "id": "call_cd1ab81af61f4abf91f27ea6", "name": "Bash", "input": { "command": "# Submit a batch of jobs, then immediately restart the worker to prove restart-survival\nfor i in $(seq 1 20); do curl -s -X POST --data-binary \"payload-$i\" http://localhost:8080/jobs/burst-$i >/dev/null; done\nsystemctl restart queue-worker.service\nsleep 2\necho \"=== burst jobs after worker restart ===\"\nsqlite3 /var/lib/job-queue/jobs.sqlite3 \"SELECT status, COUNT(*) FROM jobs WHERE id LIKE 'burst-%' GROUP BY status;\"\necho \"=== all done, attempts check ===\"\nsqlite3 /var/lib/job-queue/jobs.sqlite3 \"SELECT COUNT(*) AS done, MIN(attempts), MAX(attempts) FROM jobs WHERE id LIKE 'burst-%' AND status='done';\"\necho \"=== verify result correctness ===\"\nsqlite3 /var/lib/job-queue/jobs.sqlite3 \"SELECT id, result FROM jobs WHERE id LIKE 'burst-%' LIMIT 3;\"", "description": "Burst + worker restart durability test" }, "output": "=== burst jobs after worker restart ===\ndone|20\n=== all done, attempts check ===\n20|1|1\n=== verify result correctness ===\nburst-1|processed:payload-1\nburst-2|processed:payload-2\nburst-3|processed:payload-3\n", "is_error": false, "read_only": false, "started_after_ms": 65589, "duration_ms": 2800 }, { "id": "call_b08cd47c9cb84800a6c57a8a", "name": "Bash", "input": { "command": "# Simulate reboot ordering: stop both, re-run seed, then start both (as on boot)\nsystemctl stop queue-api.service queue-worker.service\nsystemctl restart queue-seed.service\nsleep 1\nsystemctl start queue-api.service queue-worker.service\nsleep 2\necho \"=== active state ===\"; systemctl is-active queue-api queue-worker queue-seed\necho \"=== seed jobs intact ===\"; sqlite3 /var/lib/job-queue/jobs.sqlite3 \"SELECT id,status,attempts FROM jobs WHERE id LIKE 'accepted-%';\"\necho \"=== health after simulated reboot ===\"; curl -s -w \" HTTP %{http_code}\\n\" http://localhost:8080/health\necho \"=== submit post-reboot job ===\"; curl -s -X POST --data-binary 'reboot-test' http://localhost:8080/jobs/post-reboot-1 -w \" HTTP %{http_code}\\n\"; sleep 1\ncurl -s http://localhost:8080/jobs/post-reboot-1; echo\necho \"=== final summary ===\"; sqlite3 /var/lib/job-queue/jobs.sqlite3 \"SELECT status, COUNT(*), MIN(attempts), MAX(attempts) FROM jobs GROUP BY status;\"", "description": "Full reboot-ordering simulation" }, "output": "=== active state ===\nactive\nactive\nactive\n=== seed jobs intact ===\naccepted-alpha-7d3|done|1\naccepted-beta-91e|done|1\naccepted-gamma-c42|done|1\n=== health after simulated reboot ===\nready HTTP 200\n=== submit post-reboot job ===\n HTTP 202\n{\"id\": \"post-reboot-1\", \"payload\": \"reboot-test\", \"status\": \"done\", \"result\": \"processed:reboot-test\", \"attempts\": 1}\n=== final summary ===\ndone|25|1|1\n", "is_error": false, "read_only": false, "started_after_ms": 74899, "duration_ms": 4342 }, { "id": "call_4b8a1b3c22194c9e8cef517c", "name": "Bash", "input": { "command": "systemctl is-enabled queue-api queue-worker queue-seed; echo \"=== api log tail ===\"; journalctl -u queue-api.service -n 5 --no-pager 2>&1; echo \"=== worker log tail ===\"; journalctl -u queue-worker.service -n 5 --no-pager 2>&1", "description": "Confirm units enabled for auto-start on boot" }, "output": "enabled\nenabled\nenabled\n=== api log tail ===\nAug 15 02:44:39 queue-three systemd[1]: Stopping Agent-built durable queue API slot...\nAug 15 02:44:39 queue-three systemd[1]: queue-api.service: Deactivated successfully.\nAug 15 02:44:39 queue-three systemd[1]: Stopped Agent-built durable queue API slot.\nAug 15 02:44:39 queue-three systemd[1]: queue-api.service: Consumed 216ms CPU time over 21.558s wall clock time, 10.8M memory peak, 364K written to disk, 27.9K incoming IP traffic, 35K outgoing IP traffic.\nAug 15 02:44:40 queue-three systemd[1]: Started Agent-built durable queue API slot.\n=== worker log tail ===\nAug 15 02:44:31 queue-three systemd[1]: Started Agent-built durable queue worker slot.\nAug 15 02:44:39 queue-three systemd[1]: Stopping Agent-built durable queue worker slot...\nAug 15 02:44:39 queue-three systemd[1]: queue-worker.service: Deactivated successfully.\nAug 15 02:44:39 queue-three systemd[1]: Stopped Agent-built durable queue worker slot.\nAug 15 02:44:40 queue-three systemd[1]: Started Agent-built durable queue worker slot.\n", "is_error": false, "read_only": false, "started_after_ms": 81732, "duration_ms": 53 }, { "id": "call_9fe8608dbbee492497589e77", "name": "TodoWrite", "input": { "todos": [ { "activeForm": "Writing api.py", "content": "Write /opt/job-queue/api.py (http.server, SQLite WAL)", "status": "completed" }, { "activeForm": "Writing worker.py", "content": "Write /opt/job-queue/worker.py (atomic exactly-once completion)", "status": "completed" }, { "activeForm": "Starting and verifying services", "content": "Reset failed units, start services, verify endpoints", "status": "completed" }, { "activeForm": "Verifying durability", "content": "Verify durability: restart worker, confirm jobs complete with attempts=1", "status": "completed" } ] }, "output": "Completed:\n ✓ Reset failed units, start services, verify endpoints\n ✓ Verify durability: restart worker, confirm jobs complete with attempts=1\n\nAll tasks completed. List cleared.", "is_error": false, "read_only": true, "started_after_ms": 85042, "duration_ms": 0 } ], "timing": { "total_duration_ms": 93067, "model_rounds": [ { "index": 1, "started_after_ms": 0, "duration_ms": 1291, "status": "completed", "usage": { "input_tokens": 2807, "output_tokens": 109, "cache_read_tokens": 0, "cache_creation_tokens": 0, "cost_usd": 0.0023971 } }, { "index": 2, "started_after_ms": 6994, "duration_ms": 1983, "status": "completed", "usage": { "input_tokens": 3708, "output_tokens": 160, "cache_read_tokens": 0, "cache_creation_tokens": 0, "cost_usd": 0.00320528 } }, { "index": 3, "started_after_ms": 9083, "duration_ms": 1929, "status": "completed", "usage": { "input_tokens": 6113, "output_tokens": 190, "cache_read_tokens": 0, "cache_creation_tokens": 0, "cost_usd": 0.00510568 } }, { "index": 4, "started_after_ms": 11542, "duration_ms": 18414, "status": "completed", "usage": { "input_tokens": 6616, "output_tokens": 1084, "cache_read_tokens": 5623, "cache_creation_tokens": 0, "cost_usd": 0.002667623 } }, { "index": 5, "started_after_ms": 29958, "duration_ms": 11031, "status": "completed", "usage": { "input_tokens": 8195, "output_tokens": 898, "cache_read_tokens": 7375, "cache_creation_tokens": 0, "cost_usd": 0.002455845 } }, { "index": 6, "started_after_ms": 40991, "duration_ms": 6564, "status": "completed", "usage": { "input_tokens": 9107, "output_tokens": 452, "cache_read_tokens": 8105, "cache_creation_tokens": 0, "cost_usd": 0.001924615 } }, { "index": 7, "started_after_ms": 47558, "duration_ms": 2722, "status": "completed", "usage": { "input_tokens": 9574, "output_tokens": 146, "cache_read_tokens": 8616, "cache_creation_tokens": 0, "cost_usd": 0.001478316 } }, { "index": 8, "started_after_ms": 50282, "duration_ms": 2514, "status": "completed", "usage": { "input_tokens": 9838, "output_tokens": 85, "cache_read_tokens": 8854, "cache_creation_tokens": 0, "cost_usd": 0.001418774 } }, { "index": 9, "started_after_ms": 55423, "duration_ms": 4109, "status": "completed", "usage": { "input_tokens": 9985, "output_tokens": 188, "cache_read_tokens": 8886, "cache_creation_tokens": 0, "cost_usd": 0.001636656 } }, { "index": 10, "started_after_ms": 60676, "duration_ms": 4911, "status": "completed", "usage": { "input_tokens": 10313, "output_tokens": 249, "cache_read_tokens": 9281, "cache_creation_tokens": 0, "cost_usd": 0.001733711 } }, { "index": 11, "started_after_ms": 68391, "duration_ms": 6507, "status": "completed", "usage": { "input_tokens": 10628, "output_tokens": 348, "cache_read_tokens": 9140, "cache_creation_tokens": 0, "cost_usd": 0.00209678 } }, { "index": 12, "started_after_ms": 79242, "duration_ms": 2488, "status": "completed", "usage": { "input_tokens": 11122, "output_tokens": 91, "cache_read_tokens": 9453, "cache_creation_tokens": 0, "cost_usd": 0.001818173 } }, { "index": 13, "started_after_ms": 81786, "duration_ms": 3255, "status": "completed", "usage": { "input_tokens": 11515, "output_tokens": 163, "cache_read_tokens": 10133, "cache_creation_tokens": 0, "cost_usd": 0.001850303 } }, { "index": 14, "started_after_ms": 85043, "duration_ms": 8022, "status": "completed", "usage": { "input_tokens": 11719, "output_tokens": 445, "cache_read_tokens": 10429, "cache_creation_tokens": 0, "cost_usd": 0.002266439 } } ] } }