Sidecar HTTP Proxy

This is a super simple sidecar HTTP proxy written in Rust. It is designed to be used as a sidecar for rewriting requests so that you can have an ingress controller agnostic Kubernetes Pod where the webapp in the main pod is not able to modify its context root.

Usage: sidecar-http-proxy [options]

Options:
    -h, --help          print this help menu and exit
    -V, --version       print the version and exit
    -p, --port PORT     the port to listen for requests on (default: 8080)
    -t, --target-url URL
                        the target base URL to proxy
    -s, --source-path PATH
                        the source path to remove from requests before
                        forwarding to the target (default: /)
    -c, --cache-control VALUE
                        the cache control header to inject if none is provided


Proxies requests to a remote service (with optional path prefix stripping)

Example usage in a pod

The use case is where the application (I'm looking at you Apache Flink) does not support configuring the context path to serve from. Normally you would just use a rewrite rule in your ingress controller, but of course all the ingress controllers have different syntax for rewrite rules (I'm looking at you traefik and nginx) thus if you want a simple ingress agnostic chart you need to have the URLs rewritten for you. Enter this sidecar container, which runs in the same pod and can thus access localhost ports and perform the rewrite for you.

Adding the following sidecar conatiner will serve http://127.0.0.1:8081/ at http://127.0.0.1:8080/context-root/ allowing your ingress rule to just point at that path without requiring any rewrites.

      containers:
        {{- if .Values.ingress.enabled }}
        - name: {{ .Chart.Name }}-proxy
          image: "stephenc/sidecar-http-proxy:0.1.1"
          imagePullPolicy: IfNotPresent
          command: ["/sidecar-http-proxy", "-p", "8080", "-s", "/context-root", "-t", "http://127.0.0.1:8081"]
          ports:
            - containerPort: 8080
              name: proxy
          livenessProbe:
            tcpSocket:
              port: 8080
            initialDelaySeconds: 5
            periodSeconds: 60
        {{- end }}
        - name: {{ .Chart.Name }}-app
          ...