feat: allow override renovate image (#739)

Co-authored-by: Oreste Di Modugno <oreste.dimodugno@adevinta.com>
Co-authored-by: Rhys Arkins <rhys@arkins.net>
Co-authored-by: Michael Kriese <michael.kriese@visualon.de>

README.md

@@ -100,6 +100,45 @@ jobs:
           token: ${{ secrets.RENOVATE_TOKEN }}
 ```
 
+## `renovate-image`
+
+The Renovate docker image name to use.
+If omited or `renovate-image === ''` the action will use the `renovate/renovate` docker image name otherwise.
+If a docker image name is defined, the action will use that name to pull the image.
+
+This sample will use `myproxyhub.domain.com/renovate/renovate:slim` image.
+
+```yml
+....
+jobs:
+  renovate:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v3.3.0
+      - name: Self-hosted Renovate
+        uses: renovatebot/github-action@v36.0.0
+        with:
+          renovate-image: myproxyhub.domain.com/renovate/renovate
+          token: ${{ secrets.RENOVATE_TOKEN }}
+```
+
+This sample will use `renovate/renovate:slim` image.
+
+```yml
+....
+jobs:
+  renovate:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v3.3.0
+      - name: Self-hosted Renovate
+        uses: renovatebot/github-action@v36.0.0
+        with:
+          token: ${{ secrets.RENOVATE_TOKEN }}
+```
+
 ## `useSlim`
 
 If set to `false` the action will use the full renovate image instead of the slim image.

action.yml

@@ -30,6 +30,11 @@ inputs:
     description: |
       Renovate version to use. Defaults to latest.
     required: false
+  renovate-image:
+    description: |
+      Renovate docker image name.
+      Defaults to `renovate/renovate`.
+    required: false
 runs:
   using: node16
   main: dist/index.js

src/docker.ts

@@ -2,10 +2,14 @@ import type { Input } from './input';
 
 class Docker {
   private static readonly repository = 'renovate/renovate';
+
+  private readonly dockerImage: string;
   private readonly fullTag: string;
 
   constructor(input: Input) {
     const tag = input.getVersion();
+
+    this.dockerImage = input.getDockerImage() ?? Docker.repository;
     this.fullTag = input.useSlim()
       ? tag
         ? `${tag}-slim`
@@ -14,7 +18,7 @@ class Docker {
   }
 
   image(): string {
-    return `${Docker.repository}:${this.fullTag}`;
+    return `${this.dockerImage}:${this.fullTag}`;
   }
 }
 

src/input.ts

@@ -64,6 +64,10 @@ class Input {
     return core.getInput('useSlim') !== 'false';
   }
 
+  getDockerImage(): string | null {
+    return core.getInput('renovate-image') || null;
+  }
+
   getVersion(): string | null {
     const version = core.getInput('renovate-version');
     return !!version && version !== '' ? version : null;