Inline all the versions into the default branch (#194)

This takes all the version-specific branches and inline them into the
default branch, as they are.

This also prepares a placeholder for the upcoming v1.7 version which has
beta versions since a few days ago.

Several things are now paths-triggered:

* The build system will only trigger if the related paths have been
  changed.
* Renovate will trigger specific version updates based on the paths too.
* Versions <1.2.x are not updated/built anymore (it's already the case
  from before).

The build system is also now based on buildx, to prepare for the ARM
builds coming soon.

.github/renovate.json5

@@ -3,10 +3,6 @@
 
   "baseBranches": [
     "master",
-    "branch-1.2.x",
-    "branch-1.3.x",
-    "branch-1.4.x",
-    "branch-1.5.x",
   ],
 
   "regexManagers": [
@@ -19,31 +15,52 @@
     },
   ],
 
+  // These versions are not updated anymore.
+  "ignorePaths": [
+    "v0.9.x/**",
+    "v0.10.x/**",
+    "v0.11.x/**",
+    "v0.12.x/**",
+    "v1.0.x/**",
+    "v1.1.x/**",
+  ],
+
   "packageRules": [
     {
-      "matchBaseBranches": ["master"],
+      "matchFileNames": ["latest/**"],
       "matchPackageNames": ["hashicorp/nomad"],
       "ignoreUnstable": false,
+      "groupName": "nomad-latest",
     },
     {
-      "matchBaseBranches": ["branch-1.2.x"],
+      "matchFileNames": ["v1.2.x/**"],
       "matchPackageNames": ["hashicorp/nomad"],
-      "allowedVersions": "<=1.2"
+      "allowedVersions": "<=1.2",
+      "groupName": "nomad-1.2.x",
     },
     {
-      "matchBaseBranches": ["branch-1.3.x"],
+      "matchFileNames": ["v1.3.x/**"],
       "matchPackageNames": ["hashicorp/nomad"],
       "allowedVersions": "<=1.3",
+      "groupName": "nomad-1.3.x",
     },
     {
-      "matchBaseBranches": ["branch-1.4.x"],
+      "matchFileNames": ["v1.4.x/**"],
       "matchPackageNames": ["hashicorp/nomad"],
       "allowedVersions": "<=1.4",
+      "groupName": "nomad-1.4.x",
     },
     {
-      "matchBaseBranches": ["branch-1.5.x"],
+      "matchFileNames": ["v1.5.x/**"],
       "matchPackageNames": ["hashicorp/nomad"],
       "allowedVersions": "<=1.5",
+      "groupName": "nomad-1.5.x",
+    },
+    {
+      "matchFileNames": ["v1.6.x/**"],
+      "matchPackageNames": ["hashicorp/nomad"],
+      "allowedVersions": "<=1.6",
+      "groupName": "nomad-1.6.x",
     },
   ],
 }

.github/workflows/latest-build.yml

@@ -0,0 +1,22 @@
+name: "Latest: build"
+
+on:
+  push:
+    branches:
+      - master
+    paths:
+      - latest/**
+
+  pull_request:
+    branches:
+      - master
+    paths:
+      - latest/**
+
+jobs:
+  test:
+    name: Test
+    uses: ./.github/workflows/template-build.yml
+    with:
+      platforms: linux/amd64
+      directory: latest

.github/workflows/template-build.yml

@@ -0,0 +1,56 @@
+# This builds the Docker image from the specified directory on all the
+# platforms and do a basic sanity check to verify that Nomad runs.
+name: Build
+
+on:
+  workflow_call:
+    inputs:
+      directory:
+        description: Directory where the Dockerfile is
+        required: true
+        type: string
+
+      platforms:
+        description: The platforms to build on
+        required: true
+        type: string
+
+jobs:
+  build:
+    name: Build
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Metadata
+        id: meta
+        working-directory: ${{ inputs.directory }}
+        run: |
+          echo "dockerfile=${{ inputs.directory }}/Dockerfile" >> "$GITHUB_OUTPUT"
+
+      - name: Lint the Dockerfile
+        uses: hadolint/[email protected]
+        with:
+          dockerfile: ${{ steps.meta.outputs.dockerfile }}
+
+      - name: Set up QEMU
+        id: docker-setup
+        uses: docker/setup-qemu-action@v3
+        with:
+          platforms: ${{ inputs.platforms }}
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+
+      - name: Build
+        uses: docker/build-push-action@v5
+        with:
+          context: ${{ inputs.directory }}
+          file: ${{ steps.meta.outputs.dockerfile }}
+          load: true  # load the image built locally for later use
+          platforms: ${{ inputs.platforms }}
+          push: false
+          tags: local/nomad:test
+
+      - name: Test
+        run: make test DOCKER_TAG=local/nomad:test

.github/workflows/v1.2.x-build.yml

@@ -0,0 +1,22 @@
+name: "v1.3.x: build"
+
+on:
+  push:
+    branches:
+      - master
+    paths:
+      - v1.3.x/**
+
+  pull_request:
+    branches:
+      - master
+    paths:
+      - v1.3.x/**
+
+jobs:
+  test:
+    name: Test
+    uses: ./.github/workflows/template-build.yml
+    with:
+      platforms: linux/amd64
+      directory: v1.3.x

.github/workflows/v1.3.x-build.yml

@@ -0,0 +1,22 @@
+name: "v1.3.x: build"
+
+on:
+  push:
+    branches:
+      - master
+    paths:
+      - v1.3.x/**
+
+  pull_request:
+    branches:
+      - master
+    paths:
+      - v1.3.x/**
+
+jobs:
+  test:
+    name: Test
+    uses: ./.github/workflows/template-build.yml
+    with:
+      platforms: linux/amd64
+      directory: v1.3.x

.github/workflows/v1.4.x-build.yml

@@ -0,0 +1,22 @@
+name: "v1.4.x: build"
+
+on:
+  push:
+    branches:
+      - master
+    paths:
+      - v1.4.x/**
+
+  pull_request:
+    branches:
+      - master
+    paths:
+      - v1.4.x/**
+
+jobs:
+  test:
+    name: Test
+    uses: ./.github/workflows/template-build.yml
+    with:
+      platforms: linux/amd64
+      directory: v1.4.x

.github/workflows/v1.5.x-build.yml

@@ -0,0 +1,22 @@
+name: "v1.5.x: build"
+
+on:
+  push:
+    branches:
+      - master
+    paths:
+      - v1.5.x/**
+
+  pull_request:
+    branches:
+      - master
+    paths:
+      - v1.5.x/**
+
+jobs:
+  test:
+    name: Test
+    uses: ./.github/workflows/template-build.yml
+    with:
+      platforms: linux/amd64
+      directory: v1.5.x

.github/workflows/v1.6.x-build.yml

@@ -0,0 +1,22 @@
+name: "v1.6.x: build"
+
+on:
+  push:
+    branches:
+      - master
+    paths:
+      - v1.6.x/**
+
+  pull_request:
+    branches:
+      - master
+    paths:
+      - v1.6.x/**
+
+jobs:
+  test:
+    name: Test
+    uses: ./.github/workflows/template-build.yml
+    with:
+      platforms: linux/amd64
+      directory: v1.6.x