werkator/docs/plan/07-server-mode.md

Step 07: Server Mode and HTTP API

Prerequisites: steps 04, 05, 06. Read README.md and 00-legacy-analysis.md first.

Goal

Implement the server subcommand: a persistent web server exposing build state as JSON and serving artifacts.

Design

Bootstrapping:

• CLAUDE.md notes the context starts with web type none; the server subcommand must run a web context. Preferred approach: ServerCommand launches a second SpringApplication with WebApplicationType.SERVLET and a server profile, then blocks until shutdown. Document the chosen mechanism in the code and, if it deviates, in an ADR.
• Add spring-boot-starter-web dependency.
• The watcher (step 06) is active only in the server profile.
• New config keys server.port and server.bindAddress (defaults 18080 / 0.0.0.0, as legacy).

JSON API (package de.hoennig.gittally.server), replacing the legacy /control/* endpoints:

• GET /api/builds/latest — latest build per branch.
• GET /api/builds/history — all builds, newest first.
• GET /api/builds/current — the list of running builds (there can be several, one per branch, up to builds.maxConcurrent), each with live status and log tail (?offset= for incremental log fetch, addressed by artifact key).
• GET /api/status/{commit} — effective status including Gitea lookup (replaces /control/status); must return an explicit error state on Gitea failure, never hang.
• POST /api/builds/{branch}/restart, POST /api/builds/{artifactKey}/cancel (cancel takes the artifact key because multiple builds can run concurrently), DELETE /api/builds/{artifactKey} — guarded by a simple token like the legacy cancel token; wire into executor/watcher/repository.
• GET /api/watcher — watcher health (last poll, last error).
• Artifact serving: GET /artifacts/{artifactKey}/** streaming from the artifact store, with no-cache headers for html/json/log.

Out of Scope

• HTML pages (step 08); JSON plus artifact files only.
• TLS/reverse proxy (documented in step 12).

Tests

• @WebMvcTest slices with @MockkBean per controller (see CLAUDE.md conventions).
• Contract tests: JSON shapes, error states (Gitea down → explicit unknown status, HTTP 200), cancel token rejection.
• One @SpringBootTest on the server profile proving the context boots with watcher and web enabled.

Acceptance Criteria

• ./gradlew ktlintFormat then ./gradlew build is green.
• java -jar ... server starts, GET /api/builds/latest answers, Ctrl-C shuts down cleanly (manual smoke test; document result in this file).