updated runner workflow

.github/workflows/deployment.yml

@@ -37,10 +37,15 @@ jobs:
           distribution: 'adopt'
           java-version: '17'
 
+      - name: parse flutter version
+        run: |
+          export FLUTTER_VERSION=$(./.github/workflows/get_flutter_version.sh)
+          echo "FLUTTER_VERSION=$FLUTTER_VERSION" >> $GITHUB_ENV
+
       - name: setup flutter
         uses: subosito/flutter-action@v2
         with:
-          channel: stable
+          flutter-version: ${{ env.FLUTTER_VERSION }}
           cache: true
 
       - name: cache flutter dependencies
@@ -97,10 +102,15 @@ jobs:
       - name: setup actions
         uses: actions/checkout@v3
 
+      - name: parse flutter version
+        run: |
+          export FLUTTER_VERSION=$(./.github/workflows/get_flutter_version.sh)
+          echo "FLUTTER_VERSION=$FLUTTER_VERSION" >> $GITHUB_ENV
+
       - name: setup flutter
         uses: subosito/flutter-action@v2
         with:
-          channel: stable
+          flutter-version: ${{ env.FLUTTER_VERSION }}
           cache: true
 
       - name: cache flutter dependencies
@@ -150,10 +160,16 @@ jobs:
           ruby-version: '3.0'
           bundler-cache: true
 
+      - name: parse flutter version
+        run: |
+          export FLUTTER_VERSION=$(./.github/workflows/get_flutter_version.sh)
+          echo "FLUTTER_VERSION=$FLUTTER_VERSION" >> $GITHUB_ENV
+
       - name: setup flutter
         uses: subosito/flutter-action@v2
         with:
-          channel: stable
+          flutter-version: ${{ env.FLUTTER_VERSION }}
+          cache: true
 
       - name: setup cider
         run: dart pub global activate cider

.github/workflows/get_flutter_version.sh

@@ -0,0 +1,31 @@
+#!/bin/sh
+
+# Extract the lower bound flutter version from pubspec.yaml
+# This is used to pin the version of the flutter sdk for reproducible builds.
+# The version is expected to be somewhere in the pubspec.yaml file, in the
+# "environment:" section, under the "flutter:" key.
+# The version may be a range or a single version.
+FLUTTER_VERSION=""
+
+# Fetch the "environment:" section from pubspec.yaml
+environment_keys=$(awk "/^environment:\\r?$/,/^\\r?$/" ./pubspec.yaml)
+
+# Fetch the "flutter:" line from the "environment:" section
+grep_result=$(echo "$environment_keys" | grep "^  flutter:")
+
+# Check if we found a valid flutter version
+if [ -z "$grep_result" ]; then
+  echo "No valid 'flutter:' entry found under 'environment:' in pubspec.yaml"
+  exit 1
+fi
+
+# Extract the version string from the line
+version_string=$(echo "$grep_result" | awk -F"'" '{print $2}')
+
+# Split by <, >, =, and space to find the version.
+# We look for the lower bound, so the first non-empty string is the version.
+# This should also work if the version is not a range.
+FLUTTER_VERSION=$(echo "$version_string" | awk -F"[<>= ]" '{for(i=1;i<=NF;i++) if($i!="") {print $i; exit}}')
+
+# Return the version
+echo $FLUTTER_VERSION