rust: update cluster management examples to use new API

Author: danielfrankcom

.github/workflows/rust-cm-integ-tests.yml

@@ -20,9 +20,26 @@ on:
         type: string
 
 jobs:
+  format:
+    runs-on: ubuntu-latest
+    timeout-minutes: 5
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+
+      - name: Set up Rust
+        run: rustup update
+
+      - name: Check formatting
+        working-directory: ./rust/cluster_management
+        run: |
+          rustup component add rustfmt
+          cargo fmt -- --check
+
   test:
     runs-on: ubuntu-latest
-    timeout-minutes: 15
+    timeout-minutes: 30
     permissions:
       id-token: write
       contents: read
@@ -32,19 +49,58 @@ jobs:
       pull-requests: write
 
     steps:
-    - name: Checkout code
-      uses: actions/checkout@v4
-
-    - name: Set up Rust
-      run: rustup update
-
-    - name: Configure AWS Credentials
-      uses: aws-actions/configure-aws-credentials@v4
-      with:
-        role-to-assume: ${{ secrets.RUST_IAM_ROLE }}
-        aws-region: us-east-1
-
-    - name: Configure and run integration for cluster management
-      working-directory: ./rust/cluster_management
-      run: |
-        cargo test
+      - name: Checkout code
+        uses: actions/checkout@v4
+
+      - name: Set up Rust
+        run: rustup update
+
+      - name: Configure AWS Credentials
+        uses: aws-actions/configure-aws-credentials@v4
+        with:
+          role-to-assume: ${{ secrets.RUST_IAM_ROLE }}
+          aws-region: us-east-1
+
+      - name: Configure and run integration for cluster management
+        working-directory: ./rust/cluster_management
+        run: |
+          cargo test -- --nocapture
+
+  # This job ensures all example binaries remain independently executable. The examples serve dual purposes; they are
+  # standalone binaries with main entry points for customers, and library functions for our unit tests. We need to
+  # verify the standalone functionality remains intact through future changes. Each binary should fail gracefully when
+  # environment variables are missing, which confirms they can be built and executed as an independent entry point.
+  run-binaries:
+    runs-on: ubuntu-latest
+    timeout-minutes: 5
+    
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+
+      - name: Set up Rust
+        run: rustup update
+
+      - name: Build and run all binaries
+        working-directory: ./rust/cluster_management
+        run: |
+          # Get all binary names.
+          binaries=$(find src/bin -name "*.rs" | sed 's|src/bin/||' | sed 's|\.rs$||')
+          
+          # Test each binary
+          for bin in $binaries; do
+            echo "Testing binary: $bin"
+
+            # Run the binary and capture its output
+            output=$(cargo run --bin $bin 2>&1) || true
+
+            # Check if the output contains the expected error message about environment variables
+            if echo "$output" | grep -q "env variable \`CLUSTER_REGION\` should be set"; then
+              echo "Binary correctly reported missing CLUSTER_REGION environment variable"
+            else
+              echo "Binary did not produce the expected error message about missing environment variables"
+              echo "Actual output was:"
+              echo "$output"
+              exit 1
+            fi
+          done