Modified: Caching dependencies to speed up the workflow

restore a cached version of the snappy from a previous run
If the cache is not found (cache-hit != 'true'), it installs snappy and the installed files are cached for future runs.
Caches the build directory to speed up subsequent builds (The cache key is based on the CMakeLists.txt files' hash to ensure the cache is updated when the build configuration changes).

.github/workflows/build.yml

@@ -18,11 +18,29 @@ jobs:
       with:
         submodules: true  # This ensures that the googletest submodule is also checked out
 
-    - name: Install dependencies
+    - name: Cache snappy dependencies
+      id: cache-snappy
+      uses: actions/cache@v2
+      with:
+        path: /usr/local/snappy
+        key: ${{ runner.os }}-snappy-${{ hashFiles('**/CMakeLists.txt') }}
+        restore-keys: |
+          ${{ runner.os }}-snappy-
+
+    - name: Install snappy dependencies if not cached
+      if: steps.cache-snappy.outputs.cache-hit != 'true'
       run: |
         sudo apt-get update
         sudo apt-get install -y libsnappy-dev
 
+    - name: Cache CMake build
+      uses: actions/cache@v2
+      with:
+        path: build
+        key: ${{ runner.os }}-cmake-${{ hashFiles('**/CMakeLists.txt') }}
+        restore-keys: |
+          ${{ runner.os }}-cmake-
+
     - name: Configure CMake
       run: mkdir build && cd build && cmake -DUSE_SUBMODULE_GTEST=ON ..