---
type: guide
title: Daily Run Guide
description: Operator- and tester-focused walkthrough of one daily cron tick — startup, pipeline pass, silent-on-no-matches, and retry behaviour.
tags: [guide, run, daily, tester]
timestamp: 2026-08-04T17:51:00Z
---

# Purpose

A tester or operator needs to know **what should happen** each time
the cron tick fires. This guide describes the contract from the
outside of the container, in observable terms: log lines, exit codes,
files appearing on the volume, and the "silent on no matches"
behaviour that the runner enforces.

# Triggering a Run Manually

```bash
docker compose exec tenbackward /usr/local/bin/python -m tenbackward
```

This is the same command the container's cron entry issues once per
day at `RUN_AT`. Use it to verify behaviour without waiting for the
scheduled tick.

# What You Should See

The bot uses a **JSON-per-line** logger that writes to
`/app/data/cron.log` (because the cron line redirects with
`>> /app/data/cron.log 2>&1`). Inspecting the file with
`docker compose exec tenbackward tail -n 100 /app/data/cron.log`
should show output similar to:

```json
{"ts": "2026-08-04T09:00:00+00:00", "level": "INFO", "logger": "tenbackward", "message": "startup", "event": "startup", "version": "0.1.0", "site_url": "https://blog.example.com", "run_at": "09:00", "tz": "Europe/Berlin", "hashtags": "#throwback,#10backward", "throwback_prefix": "Throwback:"}
```

On the current scaffold (`_iter_candidates` is intentionally empty),
this is the **only** line you should see — the runner emits no
`run_complete` when no candidates were found. This is the
"silent on no matches" contract.

# Expected Container Behaviour

| Scenario                                  | Lines in `cron.log`                                            | Container exit   |
|-------------------------------------------|----------------------------------------------------------------|------------------|
| Config valid, zero candidates (scaffold) | 1× `startup`                                                   | `0`              |
| Config valid, future blog step posts N≥1  | 1× `startup`, then 1× `run_complete` with `posted=N`           | `0`              |
| Pipeline raises once, recovers            | 1× `pipeline_error`, then 1× `run_complete`                    | `0`              |
| Pipeline keeps raising (budget exhausted) | `MAX_RETRIES + 1` × `pipeline_error`, then 1× `pipeline_failed` | `1`              |
| Config invalid                            | 1× `configuration_error` (extras describe what failed)          | `2`              |

> **Tester tip** — `docker compose ps` should report the container as
> `running` after a `pipeline_failed` exit *only* if cron has not yet
> fired again. A single failed pipeline tick does not kill the container
> itself; cron re-runs it the next day.

# Files the Tester Should Look For

| Path (inside container) | When it appears                            |
|-------------------------|--------------------------------------------|
| `/app/data/cron.log`    | Always (cron appends stdout/stderr here).  |
| `/app/data/posted.json` | Created on first persist; only rewritten when a new id is posted. The scaffold run does **not** create this file. |

To verify these from the host:

```bash
docker compose exec tenbackward ls -la /app/data
docker compose exec tenbackward cat /app/data/cron.log
```

# Visual Elements

This is a server-side bot, so there is no UI. The "UI" consists of:

* **Log lines on stdout** — one JSON object per `INFO`/`ERROR` event.
* **Exit code** — `0` (healthy), `1` (pipeline exhausted), or `2` (config).
* **`posted.json`** — JSON state file; its mtime changes whenever a new id is persisted.

# Examples

## Healthy scaffold tick

```bash
$ docker compose exec tenbackward python -m tenbackward
{"ts":"...","event":"startup",...}
$ echo $?
0
```

## Bad `RUN_AT`

```bash
$ RUN_AT=25:99 docker compose exec tenbackward python -m tenbackward
ERROR: RUN_AT='25:99' must be in HH:MM (24-hour) format
$ docker compose ps
tenbackward  Exit 1
```

(The error message lands on stderr in the entrypoint path and is
captured by `cron.log`.)

## Missing required env var

Unset `MAX_RETRIES`, restart the container:

```bash
$ docker compose up --build
tenbackward  | ERROR: missing required environment variable(s): MAX_RETRIES
tenbackward  exited with code 1
```

# Related

* [Environment Variable Setup](/operations/environment-setup.md)
* [Pipeline Runner](/architecture/pipeline-runner.md)
* [Logging & Run Summary](/architecture/logging.md)