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proxygrpcenvoyproxy

How can I use Envoy to route /some-prefix to a gRPC service appropriately?


I'm trying to setup Envoy to route "/account" to a gRPC service. It works fine if I set the route prefix to "/" but if I introduce "/account", it breaks. I've tried prefix_rewrite:"/" but that didn't help.

admin:
  access_log_path: /tmp/admin_access.log
  address:
    socket_address: { address: 0.0.0.0, port_value: 9901 }
static_resources:
  listeners:
    - name: listener_0
      address:
        socket_address: { address: 0.0.0.0, port_value: 3000 }
      filter_chains:
        - filters:
            - name: envoy.filters.network.http_connection_manager
              typed_config:
                "@type": type.googleapis.com/envoy.extensions.filters.network.http_connection_manager.v3.HttpConnectionManager
                codec_type: auto
                stat_prefix: ingress_http
                route_config:
                  name: local_route
                  virtual_hosts:
                    - name: local_service
                      domains: ["*"]
                      routes:
                        - match: { prefix: "/account/" }
                          route: {cluster: account_service, prefix_rewrite: "/" }
                        - match: { prefix: "/account" }
                          route: { cluster: account_service, prefix_rewrite: "/"}
                            
                http_filters:
                  - name: envoy.filters.http.grpc_web
                  - name: envoy.filters.http.router
  clusters:
    - name: account_service
      connect_timeout: 0.25s
      type: logical_dns
      http2_protocol_options: {}
      lb_policy: round_robin
      hosts: [{ socket_address: { address: account, port_value: 3400 } }]

Hitting localhost:3000/account results in:

{
  "error": "14 UNAVAILABLE: DNS resolution failed"
}

Thank you for your time. I know it is valuable!


Solution

  • prefix_rewrite won't work since it will route localhost:3000/account to account_service:3400/. Simply in your scenario, this should work. This should route localhost:3000/account to account_service:3400/account

    - match: { prefix: "/account/" }
      route: {cluster: account_service}