About

A timeout is the amount of time (duration) that Gloo Gateway waits for replies from an upstream service before the service is considered unavailable. This setting can be useful to avoid your apps from hanging or fail if no response is returned in a specific timeframe. With timeouts, calls either succeed or fail within a predicatble timeframe.

The time an app needs to process a request can vary a lot which is why applying the same timeout across services can cause a variety of issues. For example, a timeout that is too long can result in excessive latency from waiting for replies from failing services. On the other hand, a timeout that is too short can result in calls failing unnecessarily while waiting for an operation that needs responses from multiple services.

Before you begin

  1. Follow the Get started guide to install Gloo Gateway, set up a gateway resource, and deploy the httpbin sample app.

  2. Get the external address of the gateway and save it in an environment variable.

      export INGRESS_GW_ADDRESS=$(kubectl get svc -n gloo-system gloo-proxy-http -o jsonpath="{.status.loadBalancer.ingress[0]['hostname','ip']}")
echo $INGRESS_GW_ADDRESS  
  
      kubectl port-forward deployment/gloo-proxy-http -n gloo-system 8080:8080

Set up timeouts

Use a RouteOption resource to specify timeouts for a specific route.

  1. Create a RouteOption custom resource to specify your timeout rules. In the following example, the request must be completed within 20 seconds.

      kubectl apply -n httpbin -f- <<EOF
apiVersion: gateway.solo.io/v1
kind: RouteOption
metadata:
  name: timeout
  namespace: httpbin
spec:
  options:
    timeout: '20s'
EOF

  2. Create an HTTPRoute resource for the httpbin app that references the RouteOption resource that you created.

      kubectl apply -f- <<EOF
apiVersion: gateway.networking.k8s.io/v1beta1
kind: HTTPRoute
metadata:
  name: httpbin-timeout
  namespace: httpbin
spec:
  parentRefs:
  - name: http
    namespace: gloo-system
  hostnames:
    - timeout.example
  rules:
    - filters:
        - type: ExtensionRef
          extensionRef:
            group: gateway.solo.io
            kind: RouteOption
            name: timeout
      backendRefs:
        - name: httpbin
          port: 8000
EOF

  3. Send a request to the httpbin app on the timout.example domain. Verify that the request succeeds and that you see a X-Envoy-Expected-Rq-Timeout-Ms header. If the header is present, Gloo Gateway expects requests to the httpbin app to succeed within the set timeout.

      curl -vik http://$INGRESS_GW_ADDRESS:8080/headers -H "host: timeout.example:8080"
  
      curl -vik localhost:8080/headers -H "host: timeout.example"

    Example output for a successful response:

       {
    "headers": {
      "Accept": [
        "*/*"
      ],
      "Host": [
        "timeout.example:8080"
      ],
      "User-Agent": [
        "curl/7.77.0"
      ],
      "X-Envoy-Expected-Rq-Timeout-Ms": [
        "20000"
      ],
      "X-Forwarded-Proto": [
        "http"
      ],
      "X-Request-Id": [
        "0ae53bc3-2644-44f2-8603-158d2ccf9f78"
      ]
    }
   }

  4. Optional: Remove the resources that you created.

      kubectl delete httproute httpbin-timeout -n httpbin
kubectl delete routeoption timeout -n httpbin