Crossbuild docker image for different architectures (#55)

* Crossbuild docker image

* Fix yaml syntax

* Github Actions timeout disabled

* Add linux/386, linux/arm/v6, linux/arm/v7, linux/ppc64le, linux/s390x docker images

* Remove linux/386, linux/ppc64le, linux/s390x docker images

* Remove "Github Packages" from build step name

Co-authored-by: Chris C. <twin@twinnation.org>

* Split workflow file to test/docker

* Forward RELEASE variable to GITHUB_ENV

* Bring back timeout for tests

Co-authored-by: Chris C. <twin@twinnation.org>

.github/workflows/docker.yml

@@ -0,0 +1,33 @@
+name: docker
+on:
+  release:
+    types: [published]
+jobs:
+  build:
+    name: Build
+    runs-on: ubuntu-latest
+    steps:
+      - name: Check out code
+        uses: actions/checkout@v2
+      - name: Get image repository
+        run: echo IMAGE_REPOSITORY=$(echo ${{ github.repository }} | tr '[:upper:]' '[:lower:]') >> $GITHUB_ENV
+      - name: Get the release
+        run: echo RELEASE=${GITHUB_REF/refs\/tags\//} >> $GITHUB_ENV
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v1
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v1
+      - name: Login to Docker Registry
+        uses: docker/login-action@v1
+        with:
+          username: ${{ secrets.DOCKER_USERNAME  }}
+          password: ${{ secrets.DOCKER_PASSWORD }}
+      - name: Build and push docker image
+        uses: docker/build-push-action@v2
+        with:
+          platforms: linux/amd64,linux/arm/v6,linux/arm/v7,linux/arm64
+          pull: true
+          push: true
+          tags: |
+            ${{ env.IMAGE_REPOSITORY }}
+            ${{ env.IMAGE_REPOSITORY }}:${{ env.RELEASE }}

README.md

@@ -44,6 +44,7 @@ core applications: https://status.twinnation.org/
   - [Basic authentication](#basic-authentication)
   - [disable-monitoring-lock](#disable-monitoring-lock)
   - [Service groups](#service-groups)
+  - [Exposing Gatus on a custom port](#exposing-gatus-on-a-custom-port)
 
 
 ## Features
@@ -144,6 +145,7 @@ Note that you can also add environment variables in the configuration file (i.e.
 | `security.basic.username`                | Username for Basic authentication                                             | Required `""`  |
 | `security.basic.password-sha512`         | Password's SHA512 hash for Basic authentication                               | Required `""`  |
 | `disable-monitoring-lock`                | Whether to [disable the monitoring lock](#disable-monitoring-lock)            | `false`        |
+| `web`                                    | Web configuration                                                             | `{}`           |
 | `web.address`                            | Address to listen on                                                          | `0.0.0.0`      |
 | `web.port`                               | Port to listen on                                                             | `8080`         |
 | `web.context-root`                       | Context root at which Gatus will be exposed (frontend and backend)            | `/`            |
@@ -661,4 +663,20 @@ services:
 
 The configuration above will result in a dashboard that looks like this:
 
-![Gatus Service Groups](.github/assets/service-groups.png)
+![Gatus Service Groups](.github/assets/service-groups.png)
+
+
+### Exposing Gatus on a custom port
+
+By default, Gatus is exposed on port `8080`, but you may specify a different port by setting the `web.port` parameter:
+```yaml
+web:
+  port: 8081
+```
+
+If you're using a PaaS like Heroku that doesn't let you set a custom port and exposes it through an environment
+variable instead, you can use that environment variable directly in the configuration file:
+```yaml
+web:
+  port: ${PORT}
+```