Remove double slashes from requests

Problem: double slashes in a request can cause the request not to resolve

Any request that contains a two (or more) consecutive slashes can result in a 404 error. For example /hello//world/. The problem in this example is the "//" between hello and world.

Solution: filter for double slashes

Apply a configuration to your Istio ingress to filter for double slashes in requests and replace them.

  1. Create a new configuration file named apigee-merge-slash-filter.yaml.
  2. Paste the following content into the file: 
    apiVersion: networking.istio.io/v1alpha3
kind: EnvoyFilter
metadata:
  name: apigee-merge-slashes
  namespace: istio-system
spec:
  workloadSelector:
    labels:
      app: istio-ingressgateway
  configPatches:
  - applyTo: NETWORK_FILTER # http connection manager is a filter in Envoy
    match:
      context: GATEWAY
      listener:
        filterChain:
          filter:
            name: "envoy.http_connection_manager"
    patch:
      operation: MERGE
      value:
        typed_config:
          "@type": "type.googleapis.com/envoy.config.filter.network.http_connection_manager.v2.HttpConnectionManager"
          merge_slashes: true
  3. Apply the configuration with the following command: 
    kubectl apply -f apigee-merge-slash-filter.yaml