Added heroku prebuild and postbuild scripts

bin/compile

@@ -118,11 +118,14 @@ header "Restoring cache"
 restore_cache | output "$LOG_FILE"
 
 build_dependencies() {
+  local has_prebuild_script=$(read_json "$BUILD_DIR/package.json" ".scripts[\"heroku-prebuild\"]")
+  local has_postbuild_script=$(read_json "$BUILD_DIR/package.json" ".scripts[\"heroku-postbuild\"]")
+
   if $PREBUILD; then
     echo "Prebuild detected (node_modules already exists)"
-    rebuild_node_modules "$BUILD_DIR"
+    rebuild_node_modules "$BUILD_DIR" "$has_prebuild_script" "$has_postbuild_script"
   else
-    install_node_modules "$BUILD_DIR"
+    install_node_modules "$BUILD_DIR" "$has_prebuild_script" "$has_postbuild_script"
   fi
 }
 

lib/dependencies.sh

 install_node_modules() {
   local build_dir=${1:-}
+  local has_prebuild_script=${2:-}
+  local has_postbuild_script=${3:-}
 
   if [ -e $build_dir/package.json ]; then
     cd $build_dir
+    if [ -n "$has_prebuild_script" ]; then
+      echo "Running prebuild script"
+      npm run heroku-prebuild
+    fi
     echo "Pruning any extraneous modules"
     npm prune --unsafe-perm --userconfig $build_dir/.npmrc 2>&1
     if [ -e $build_dir/npm-shrinkwrap.json ]; then
@@ -11,6 +17,10 @@ install_node_modules() {
       echo "Installing node modules (package.json)"
     fi
     npm install --unsafe-perm --userconfig $build_dir/.npmrc 2>&1
+    if [ -n "$has_postbuild_script" ]; then
+      echo "Running postbuild script"
+      npm run heroku-postbuild
+    fi
   else
     echo "Skipping (no package.json)"
   fi
@@ -18,9 +28,15 @@ install_node_modules() {
 
 rebuild_node_modules() {
   local build_dir=${1:-}
+  local has_prebuild_script=${2:-}
+  local has_postbuild_script=${3:-}
 
   if [ -e $build_dir/package.json ]; then
     cd $build_dir
+    if [ -n "$has_prebuild_script" ]; then
+      echo "Running prebuild script"
+      npm run heroku-prebuild
+    fi
     echo "Rebuilding any native modules"
     npm rebuild 2>&1
     if [ -e $build_dir/npm-shrinkwrap.json ]; then
@@ -29,6 +45,10 @@ rebuild_node_modules() {
       echo "Installing any new modules (package.json)"
     fi
     npm install --unsafe-perm --userconfig $build_dir/.npmrc 2>&1
+    if [ -n "$has_postbuild_script" ]; then
+      echo "Running postbuild script"
+      npm run heroku-postbuild
+    fi
   else
     echo "Skipping (no package.json)"
   fi

test/fixtures/pre-post-build-scripts/README.md

+A fake README, to keep npm from polluting stderr.
\ No newline at end of file

test/fixtures/pre-post-build-scripts/package.json

+{
+  "name": "node-buildpack-test-app",
+  "version": "0.0.1",
+  "description": "node buildpack integration test app",
+  "repository" : {
+    "type" : "git",
+    "url" : "http://github.com/example/example.git"
+  },
+  "engines": {
+    "node": "~0.10.0"
+  },
+  "scripts" : {
+    "heroku-prebuild" : "echo heroku-prebuild hook message",
+    "heroku-postbuild" : "echo heroku-postbuild hook message"
+  }
+}

test/run

@@ -471,6 +471,15 @@ testMultiExport() {
   assertCapturedSuccess
 }
 
+testPrePostBuildScripts() {
+  compile "pre-post-build-scripts"
+  assertCaptured "Running prebuild script"
+  assertCaptured "echo heroku-prebuild hook message"
+  assertCaptured "Running postbuild script"
+  assertCaptured "echo heroku-postbuild hook message"
+  assertCapturedSuccess
+}
+
 # Utils
 
 pushd $(dirname 0) >/dev/null