gitFlow/cmd/gitflow/watch.go
dimitar 0c9c07e8de feat: phase 4 — periodic scanning (watch mode) with change detection
Add the scheduling layer and the watch command so gitflow can rescan
repositories on an interval and surface state changes.

Scheduler (internal/scheduler):
- Scheduler runs a callback immediately and then on a time.Ticker until
  the context is cancelled; interval <= 0 means a single run
- Graceful shutdown: cancellation is never reported as an error (checked
  on the first run and after every run), so Ctrl-C / SIGTERM exit cleanly
- A non-cancellation run error stops the loop and is propagated

Change detection (pkg/status):
- Changed(prev, next) compares snapshots per repository path — status,
  branch, detached flag, ahead/behind, stash count, and file counts —
  and returns the repositories whose observable state differs, including
  repositories that newly appear

Watch command (cmd/gitflow):
- newWatchCmd validates that --interval is positive, prompts for the
  parent directory on a TTY when --dir is absent, and drives the
  scheduler with ScanOnce
- Each frame clears the screen on a terminal (or prints a RFC3339 header
  when output is piped, so watch doubles as a lightweight logger) and
  renders through the presenter
- Footer shows changed repositories since the previous frame ("▲ name:
  status") and the next scan time; JSON format emits one document per
  frame for scripting
- SIGINT/SIGTERM handled via signalContext for a clean stop

Testing:
- Scheduler: single run, periodic repetition, stop-on-error, pre-cancelled
  context, and cancellation-during-run (no error reported)
- status.Changed: unchanged repos ignored; status, file-count, and
  newly-appeared repos detected

Verified: go build, go vet, go test -race, gofmt clean; manual watch
smoke test over a scratch directory with 1s interval — frames render,
SIGINT and SIGTERM both exit 0 with no orphaned processes.
2026-08-02 08:44:29 +02:00

96 lines
2.6 KiB
Go

package main
import (
"context"
"errors"
"fmt"
"os"
"time"
"github.com/spf13/cobra"
"gitea.oblak.solutions/dimitar/gitFlow/internal/app"
"gitea.oblak.solutions/dimitar/gitFlow/internal/config"
"gitea.oblak.solutions/dimitar/gitFlow/internal/presenter"
"gitea.oblak.solutions/dimitar/gitFlow/internal/scheduler"
"gitea.oblak.solutions/dimitar/gitFlow/pkg/status"
)
// newWatchCmd repeatedly scans on an interval until interrupted.
func newWatchCmd() *cobra.Command {
cmd := &cobra.Command{
Use: "watch",
Short: "Repeatedly scan repositories on an interval",
Args: cobra.NoArgs,
RunE: func(cmd *cobra.Command, _ []string) error {
cfg, err := config.Load(cmd.Flags())
if err != nil {
return err
}
if cfg.Interval <= 0 {
return errors.New("watch requires a positive --interval (e.g. --interval 30s)")
}
// Same interactive prompt as scan, per the README.
if !cmd.Flags().Changed("dir") && isTerminal(os.Stdin) {
if d, err := promptDir(cfg.Dir); err == nil {
cfg.Dir = d
}
}
ctx, stop := signalContext()
defer stop()
a, err := app.New(cfg)
if err != nil {
return err
}
opts := presenter.Options{Color: presenter.ParseColorMode(cfg.Color)}
var prev status.ScanResult
first := true
run := func(ctx context.Context) error {
result, err := a.ScanOnce(ctx)
if err != nil {
return err
}
if cfg.Format == "json" {
return presenter.Present(os.Stdout, cfg.Format, result, opts)
}
renderWatchFrame(result, prev, first, cfg, opts)
prev = result
first = false
return nil
}
sched := scheduler.New(cfg.Interval, run)
return sched.Run(ctx)
},
}
config.RegisterFlags(cmd.Flags())
return cmd
}
// renderWatchFrame clears the screen (or prints a timestamp header when
// output is not a terminal), renders the scan, and prints a footer with
// changed repositories and the next scan time.
func renderWatchFrame(result, prev status.ScanResult, first bool, cfg *config.Config, opts presenter.Options) {
if isTerminal(os.Stdout) {
fmt.Fprint(os.Stdout, "\x1b[2J\x1b[H")
} else {
fmt.Fprintf(os.Stdout, "--- %s ---\n", time.Now().Format(time.RFC3339))
}
if err := presenter.Present(os.Stdout, cfg.Format, result, opts); err != nil {
fmt.Fprintf(os.Stderr, "render: %v\n", err)
return
}
if !first {
for _, r := range status.Changed(prev, result) {
fmt.Fprintf(os.Stdout, "▲ %s: %s\n", r.Name, r.Status)
}
}
fmt.Fprintf(os.Stdout, "watching %s every %s — next scan at %s (Ctrl-C to stop)\n",
cfg.Dir, cfg.Interval, time.Now().Add(cfg.Interval).Format("15:04:05"))
}