Automate SwiftPM updates. (#6836)

Summary:

Let's make the versioning daily and create a new dedicated branch with swiftpm packages for it, so that the clients can pin themselves to a specific version and never run into checksum mismatch issues when we overwrite the binaries on S3.

Differential Revision: D65908021

Author: shoumikhin

.github/workflows/apple.yml

@@ -25,6 +25,9 @@ concurrency:
   group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.sha }}-${{ github.event_name == 'workflow_dispatch' }}-${{ github.event_name == 'schedule' }}
   cancel-in-progress: true
 
+env:
+  VERSION: "0.4.0-$(date +%Y%m%d)"
+
 jobs:
   build-demo-ios:
     name: build-demo-ios
@@ -122,7 +125,7 @@ jobs:
       timeout: 90
       script: |
         BUILD_TOOL=cmake
-        VERSION="latest"
+        VERSION="${{ env.VERSION }}"
         FRAMEWORKS=(
           "executorch"
           "backend_coreml"
@@ -203,6 +206,7 @@ jobs:
         shell: bash
         run: |
           set -eux
+          VERSION="${{ env.VERSION }}"
 
           pip install awscli==1.32.18
 
@@ -211,11 +215,45 @@ jobs:
             AWS_CMD="aws s3 cp"
           fi
 
+          CHECKSUMS=()
           for FILENAME in "${RUNNER_TEMP}"/frameworks-ios/*.zip; do
             [ -e "${FILENAME}" ] || continue
-            shasum -a 256 "${FILENAME}"
+            FRAMEWORK_NAME=$(basename "${FILENAME}" | sed "s/-${VERSION}.zip//")
+            CHECKSUM=$(shasum -a 256 "${FILENAME}" | cut -d ' ' -f1)
             ${AWS_CMD} "${FILENAME}" s3://ossci-ios/executorch/ --acl public-read
+            CHECKSUMS["${FRAMEWORK_NAME}"]="${CHECKSUM}"
           done
+          echo "${CHECKSUMS[@]}" > checksums.txt
+
+      - name: Update SwiftPM
+        shell: bash
+        run: |
+          set -eux
+          VERSION="${{ env.VERSION }}"
+
+          git clone https://github.com/pytorch/executorch.git --branch swiftpm --depth 1
+          cd executorch
+          if git show-ref --verify --quiet refs/heads/swiftpm-${VERSION}; then
+            git checkout "swiftpm-${VERSION}"
+          else
+            git checkout -b "swiftpm-${VERSION}"
+          fi
+
+          cp -f Package.swift.template Package.swift
+          sed -i '' "s/__VERSION__/${VERSION}/g" Package.swift
+
+          while read -r FRAMEWORK CHECKSUM; do
+            sed -i '' "s/__SHA256_${FRAMEWORK}__/${CHECKSUM}/g" Package.swift
+          done < ../checksums.txt
+
+          if [[ "${UPLOAD_ON_MAIN:-0}" == "1" ]]; then
+            git add Package.swift
+            git commit -m "${VERSION}"
+            git push origin "swiftpm-${VERSION}"
+          else
+            echo "Draft Package.swift:"
+            cat Package.swift
+          fi
 
   build-benchmark-app:
     name: build-benchmark-app