1 files changed, 40 insertions, 0 deletions
diff --git a/internal/health/health.go b/internal/health/health.go
new file mode 100644
index 0000000..d1c9df3
--- /dev/null
+++ b/internal/health/health.go
@@ -0,0 +1,40 @@
+// Package health checks whether a freshly (re)started app is up, by polling
+// its declared health endpoint - shared by both internal/deploy and skiff
+// config's own restart-and-verify sequence.
+package health
+
+import (
+	"context"
+	"fmt"
+	"net/http"
+	"time"
+
+	"skiff/internal/appmeta"
+	"skiff/internal/layout"
+)
+
+func WaitHealthy(ctx context.Context, meta appmeta.Meta) error {
+	url := fmt.Sprintf("http://%s:%d%s", meta.IP, meta.Port, meta.HealthPath)
+	deadline := time.Now().Add(layout.HealthTimeoutSecs * time.Second)
+	client := &http.Client{Timeout: 2 * time.Second}
+
+	var lastErr error
+	for time.Now().Before(deadline) {
+		req, err := http.NewRequestWithContext(ctx, http.MethodGet, url, nil)
+		if err != nil {
+			return err
+		}
+		resp, err := client.Do(req)
+		if err == nil {
+			resp.Body.Close()
+			if resp.StatusCode < 300 {
+				return nil
+			}
+			lastErr = fmt.Errorf("status %d", resp.StatusCode)
+		} else {
+			lastErr = err
+		}
+		time.Sleep(500 * time.Millisecond)
+	}
+	return fmt.Errorf("never became healthy at %s: %w", url, lastErr)
+}