feat: add cache, outbound HTTP, request protection, tasks and module scaffolding

middleware/timeout.go

@@ -0,0 +1,35 @@
+package middleware
+
+import (
+	"context"
+	"time"
+
+	apierrors "git.yuntuo.hk/k2safe/go-omni/errors"
+	"git.yuntuo.hk/k2safe/go-omni/httpx"
+)
+
+// Timeout applies a cooperative deadline to handlers and downstream calls.
+// It does not spawn a goroutine or race a handler's response. Business code must
+// observe Context().Done(); an already committed response cannot be replaced.
+func Timeout(duration time.Duration) httpx.Middleware {
+	if duration <= 0 {
+		panic("middleware: timeout must be positive")
+	}
+	return func(next httpx.Handler) httpx.Handler {
+		return func(c *httpx.Context) error {
+			parent := c.Context()
+			ctx, cancel := context.WithTimeout(parent, duration)
+			defer cancel()
+			c.WithContext(ctx)
+			defer c.WithContext(parent)
+			if ctx.Err() != nil {
+				return apierrors.New(504, "REQUEST_TIMEOUT", "request deadline exceeded")
+			}
+			err := next(c)
+			if ctx.Err() == context.DeadlineExceeded && !c.Responded() {
+				return apierrors.New(504, "REQUEST_TIMEOUT", "request deadline exceeded").WithCause(err)
+			}
+			return err
+		}
+	}
+}