Rene Nochebuena
e1b6b7ddd7
HTTP health check handler with parallel goroutine-per-check execution, 5 s request-derived timeout, and two-level criticality (LevelCritical → 503, LevelDegraded → 200). What's included: - `Checkable` interface (HealthCheck / Name / Priority) and `Level` type with LevelCritical and LevelDegraded constants - `NewHandler(logger, checks...)` returning http.Handler; runs all checks concurrently via buffered channel, returns JSON with per-component status and latency - `ComponentStatus` and `Response` types for the JSON response body Tested-via: todo-api POC integration Reviewed-against: docs/adr/
57 lines
1.3 KiB
Markdown
57 lines
1.3 KiB
Markdown
# health
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Stdlib `http.Handler` for service health checks. Runs all checks concurrently and returns a JSON summary.
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## Install
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```
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go get code.nochebuena.dev/go/health
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```
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## Usage
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```go
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handler := health.NewHandler(logger, db, cache, queue)
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r.Get("/health", handler)
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```
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### Response
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```json
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{
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"status": "UP",
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"components": {
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"db": {"status": "UP", "latency": "1.2ms"},
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"cache": {"status": "DOWN", "latency": "5ms", "error": "connection refused"}
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}
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}
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```
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| Overall status | HTTP code | Condition |
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|---|---|---|
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| `UP` | 200 | All checks pass |
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| `DEGRADED` | 200 | One or more `LevelDegraded` checks fail; no critical failures |
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| `DOWN` | 503 | One or more `LevelCritical` checks fail |
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## Implementing `Checkable`
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```go
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func (d *DB) HealthCheck(ctx context.Context) error { return d.pool.PingContext(ctx) }
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func (d *DB) Name() string { return "postgres" }
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func (d *DB) Priority() health.Level { return health.LevelCritical }
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```
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## Logger
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`health.Logger` is a duck-typed interface satisfied by `logz.Logger` without importing it.
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```go
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type Logger interface {
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Debug(msg string, args ...any)
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Info(msg string, args ...any)
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Warn(msg string, args ...any)
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Error(msg string, err error, args ...any)
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WithContext(ctx context.Context) Logger
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}
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```
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