feat(updater): ComposeExecutor shells out to docker compose

internal/updater/compose_executor.go

@@ -0,0 +1,54 @@
+package updater
+
+import (
+	"context"
+	"fmt"
+	"os/exec"
+	"strings"
+
+	"github.com/shcizo/package-updater/internal/discovery"
+)
+
+// ComposeExecutor invokes `docker compose` as a subprocess.
+type ComposeExecutor struct{}
+
+// NewComposeExecutor returns an executor that shells out to docker compose.
+func NewComposeExecutor() *ComposeExecutor {
+	return &ComposeExecutor{}
+}
+
+// Execute runs `docker compose -f <file>... -p <project> pull <service>`
+// followed by `... up -d <service>`. Working directory is set to
+// job.WorkingDir so any relative paths in the compose file resolve correctly.
+func (e *ComposeExecutor) Execute(ctx context.Context, job discovery.Job) error {
+	if job.Refused {
+		return fmt.Errorf("refused: %s", job.RefusedReason)
+	}
+	if err := e.run(ctx, job, "pull"); err != nil {
+		return fmt.Errorf("pull: %w", err)
+	}
+	if err := e.run(ctx, job, "up", "-d"); err != nil {
+		return fmt.Errorf("up: %w", err)
+	}
+	return nil
+}
+
+func (e *ComposeExecutor) run(ctx context.Context, job discovery.Job, args ...string) error {
+	cliArgs := []string{"compose"}
+	for _, f := range job.ConfigFiles {
+		cliArgs = append(cliArgs, "-f", f)
+	}
+	cliArgs = append(cliArgs, "-p", job.Project)
+	cliArgs = append(cliArgs, args...)
+	cliArgs = append(cliArgs, job.Service)
+
+	cmd := exec.CommandContext(ctx, "docker", cliArgs...)
+	cmd.Dir = job.WorkingDir
+
+	out, err := cmd.CombinedOutput()
+	if err != nil {
+		return fmt.Errorf("docker %s: %w (output: %s)",
+			strings.Join(args, " "), err, strings.TrimSpace(string(out)))
+	}
+	return nil
+}