GHA: Add custom sccache setup action

Add a custom sccache setup composite action which we subsequently use throughout the entire build process. This allows us to centralise the logic for the configuration of the sccache bucket, enabling authenticated access to S3 if possible.

Author: brianmichel

.github/actions/setup-sccache/action.yml

@@ -0,0 +1,67 @@
+name: "Setup sccache"
+description: "Sets up sccache with S3 or local disk configuration"
+
+inputs:
+  disk-max-size:
+    description: "The maximum size of the local disk cache in MB if S3 is unavailable."
+    required: true
+  disk-cache-key:
+    description: "The key to use for the local disk cache."
+    required: true
+  s3-bucket:
+    description: "The s3 bucket to use for cache storage."
+    required: false
+  s3-bucket-encryption:
+    description: "Whether to enable server-side encryption for the S3 bucket."
+    required: false
+    default: "true"
+  aws-arn:
+    description: "The ARN of the AWS role to assume which has read/write access to the S3 bucket."
+    required: false
+  aws-region:
+    description: "The region of the S3 bucket to use for the cache"
+    required: false
+
+runs:
+  using: composite
+  steps:
+    - name: Configure caching enviornment
+      shell: pwsh
+      run: |
+        $AWSArn = '${{ inputs.aws-arn }}'
+        if ($AWSArn) {
+          $requiredParams = @{
+              's3-bucket' = '${{ inputs.s3-bucket }}'
+              's3-bucket-encryption' = '${{ inputs.s3-bucket-encryption }}'
+              'aws-region' = '${{ inputs.aws-region }}'
+          }
+
+          foreach ($param in $requiredParams.GetEnumerator()) {
+              if ([string]::IsNullOrEmpty($param.Value)) {
+                  Write-Error -Message "$($param.Key) input cannot be empty when aws-arn is provided" -ErrorAction Stop
+              }
+          }
+
+          Write-Host "Using S3 bucket ${{ inputs.s3-bucket }} for cache storage."
+          Write-Host SCCACHE_BUCKET=${{ inputs.s3-bucket }} | Out-File -FilePath $env:GITHUB_ENV -Encoding utf8 -Append
+          Write-Host SCCACHE_REGION=${{ inputs.aws-region }} | Out-File -FilePath $env:GITHUB_ENV -Encoding utf8 -Append
+          Write-Host SCCACHE_S3_SERVER_SIDE_ENCRYPTION=${{ inputs.s3-bucket-encryption }} | Out-File -FilePath $env:GITHUB_ENV -Encoding utf8 -Append
+        } else {
+          Write-Host "Using local disk cache."
+          Write-Host SCCACHE_DIRECT='on' | Out-File -FilePath $env:GITHUB_ENV -Encoding utf8 -Append
+        }
+
+    - name: Authenticate to AWS
+      uses: aws-actions/configure-aws-credentials@v3
+      if: inputs.aws-arn != ''
+      with:
+        role-to-assume: ${{ inputs.aws-arn }}
+        role-session-name: ToolchainCISccacheAccess
+        aws-region: ${{ inputs.aws-region }}
+
+    - name: Setup sccache
+      uses: hendrikmuhs/ccache-action@a1209f81afb8c005c13b4296c32e363431bffea5 # v1.2.17
+      with:
+        max-size: ${{ inputs.disk-max-size }}
+        key: ${{ inputs.disk-cache-key }}
+        variant: sccache

.github/workflows/swift-toolchain.yml

@@ -343,11 +343,10 @@ jobs:
           echo "hash=$hash" >> $env:GITHUB_OUTPUT
 
       - name: Setup sccache
-        uses: hendrikmuhs/ccache-action@2e0e89e8d74340a03f75d58d02aae4c5ee1b15c6
+        uses: ./SourceCache/swift-build/.github/actions/setup-sccache
         with:
-          max-size: 100M
-          key: ${{ steps.workspace_hash.outputs.hash }}-${{ matrix.os }}-${{ matrix.arch }}-sqlite
-          variant: sccache
+          disk-max-size: 100M
+          disk-cache-key: ${{ steps.workspace_hash.outputs.hash }}-${{ matrix.os }}-${{ matrix.arch }}-sqlite
 
       - name: Configure SQLite
         run: |
@@ -560,6 +559,11 @@ jobs:
     name: ${{ matrix.os }} ${{ matrix.arch }} CMark GFM
 
     steps:
+      - uses: actions/[email protected]
+        with:
+          path: ${{ github.workspace }}/SourceCache/swift-build
+          show-progress: false
+
       - uses: actions/[email protected]
         with:
           repository: swiftlang/swift-cmark
@@ -589,11 +593,10 @@ jobs:
           echo "hash=$hash" >> $env:GITHUB_OUTPUT
 
       - name: Setup sccache
-        uses: hendrikmuhs/ccache-action@2e0e89e8d74340a03f75d58d02aae4c5ee1b15c6
+        uses: ./SourceCache/swift-build/.github/actions/setup-sccache
         with:
-          max-size: 1M
-          key: ${{ steps.workspace_hash.outputs.hash }}-${{ matrix.os }}-${{ matrix.arch }}-cmark-gfm
-          variant: sccache
+          disk-max-size: 1M
+          disk-cache-key: ${{ steps.workspace_hash.outputs.hash }}-${{ matrix.os }}-${{ matrix.arch }}-cmark-gfm
 
       - name: Configure cmark-gfm
         run: >
@@ -633,6 +636,11 @@ jobs:
     name: ${{ matrix.os }} ${{ matrix.arch }} Compiler Build Tools
 
     steps:
+      - uses: actions/[email protected]
+        with:
+          path: ${{ github.workspace }}/SourceCache/swift-build
+          show-progress: false
+
       - uses: thebrowsercompany/gha-download-tar-artifact@59992d91335d4ecba543c8535f7d07238e42125d # main
         with:
           name: ${{ matrix.os }}-${{ matrix.arch }}-cmark-gfm-${{ inputs.swift_cmark_version }}
@@ -673,11 +681,10 @@ jobs:
           echo "hash=$hash" >> $env:GITHUB_OUTPUT
 
       - name: Setup sccache
-        uses: hendrikmuhs/ccache-action@2e0e89e8d74340a03f75d58d02aae4c5ee1b15c6
+        uses: ./SourceCache/swift-build/.github/actions/setup-sccache
         with:
-          max-size: 100M
-          key: ${{ steps.workspace_hash.outputs.hash }}-${{ matrix.os }}-${{ matrix.arch }}-build_tools
-          variant: sccache
+          disk-max-size: 100M
+          disk-cache-key: ${{ steps.workspace_hash.outputs.hash }}-${{ matrix.os }}-${{ matrix.arch }}-build_tools
 
       - name: Configure Tools
         run: |
@@ -915,6 +922,11 @@ jobs:
     name: ${{ matrix.os }} ${{ matrix.arch }} ${{ matrix.variant }} Toolchain
 
     steps:
+      - uses: actions/[email protected]
+        with:
+          path: ${{ github.workspace }}/SourceCache/swift-build
+          show-progress: false
+
       - uses: thebrowsercompany/gha-download-tar-artifact@59992d91335d4ecba543c8535f7d07238e42125d # main
         with:
           name: ${{ inputs.build_os }}-${{ inputs.build_arch }}-build-tools
@@ -1070,11 +1082,10 @@ jobs:
           echo "hash=$hash" >> $env:GITHUB_OUTPUT
 
       - name: Setup sccache
-        uses: hendrikmuhs/ccache-action@2e0e89e8d74340a03f75d58d02aae4c5ee1b15c6
+        uses: ./SourceCache/swift-build/.github/actions/setup-sccache
         with:
-          max-size: 500M
-          key: ${{ steps.workspace_hash.outputs.hash }}-${{ matrix.os }}-${{ matrix.arch }}-${{ matrix.variant }}-compilers
-          variant: sccache
+          disk-max-size: 500M
+          disk-cache-key: ${{ steps.workspace_hash.outputs.hash }}-${{ matrix.os }}-${{ matrix.arch }}-${{ matrix.variant }}-compilers
 
       - name: Setup context
         id: setup-context
@@ -1316,6 +1327,11 @@ jobs:
     name: ${{ matrix.os }} ${{ matrix.arch }} zlib
 
     steps:
+      - uses: actions/[email protected]
+        with:
+          path: ${{ github.workspace }}/SourceCache/swift-build
+          show-progress: false
+
       - uses: actions/[email protected]
         with:
           repository: madler/zlib
@@ -1345,11 +1361,10 @@ jobs:
           echo "hash=$hash" >> $env:GITHUB_OUTPUT
 
       - name: Setup sccache
-        uses: hendrikmuhs/ccache-action@2e0e89e8d74340a03f75d58d02aae4c5ee1b15c6
+        uses: ./SourceCache/swift-build/.github/actions/setup-sccache
         with:
-          max-size: 100M
-          key: ${{ steps.workspace_hash.outputs.hash }}-${{ matrix.os }}-${{ matrix.arch }}-zlib
-          variant: sccache
+          disk-max-size: 100M
+          disk-cache-key: ${{ steps.workspace_hash.outputs.hash }}-${{ matrix.os }}-${{ matrix.arch }}-zlib
 
       - uses: nttld/setup-ndk@v1
         if: matrix.os == 'Android'
@@ -1406,6 +1421,11 @@ jobs:
     name: ${{ matrix.os }} ${{ matrix.arch }} curl
 
     steps:
+      - uses: actions/[email protected]
+        with:
+          path: ${{ github.workspace }}/SourceCache/swift-build
+          show-progress: false
+
       - uses: actions/[email protected]
         with:
           repository: curl/curl
@@ -1440,11 +1460,10 @@ jobs:
           echo "hash=$hash" >> $env:GITHUB_OUTPUT
 
       - name: Setup sccache
-        uses: hendrikmuhs/ccache-action@2e0e89e8d74340a03f75d58d02aae4c5ee1b15c6
+        uses: ./SourceCache/swift-build/.github/actions/setup-sccache
         with:
-          max-size: 100M
-          key: ${{ steps.workspace_hash.outputs.hash }}-${{ matrix.os }}-${{ matrix.arch }}-curl
-          variant: sccache
+          disk-max-size: 100M
+          disk-cache-key: ${{ steps.workspace_hash.outputs.hash }}-${{ matrix.os }}-${{ matrix.arch }}-curl
 
       - uses: nttld/setup-ndk@v1
         if: matrix.os == 'Android'
@@ -1577,6 +1596,11 @@ jobs:
     name: ${{ matrix.os }} ${{ matrix.arch }} libxml2
 
     steps:
+      - uses: actions/[email protected]
+        with:
+          path: ${{ github.workspace }}/SourceCache/swift-build
+          show-progress: false
+
       - uses: actions/[email protected]
         with:
           repository: gnome/libxml2
@@ -1607,11 +1631,10 @@ jobs:
           echo "hash=$hash" >> $env:GITHUB_OUTPUT
 
       - name: Setup sccache
-        uses: hendrikmuhs/ccache-action@2e0e89e8d74340a03f75d58d02aae4c5ee1b15c6
+        uses: ./SourceCache/swift-build/.github/actions/setup-sccache
         with:
-          max-size: 100M
-          key: ${{ steps.workspace_hash.outputs.hash }}-${{ matrix.os }}-${{ matrix.arch }}-libxml2
-          variant: sccache
+          disk-max-size: 100M
+          disk-cache-key: ${{ steps.workspace_hash.outputs.hash }}-${{ matrix.os }}-${{ matrix.arch }}-libxml2
 
       - uses: nttld/setup-ndk@v1
         if: matrix.os == 'Android'