Merge pull request #60 from strongloop/feature/skip-builtin-loopback-models

Skip definitions of built-in loopback models

lib/compiler.js

@@ -5,6 +5,7 @@ var path = require('path');
 var toposort = require('toposort');
 var ConfigLoader = require('./config-loader');
 var debug = require('debug')('loopback:boot:compiler');
+var Module = require('module');
 
 /**
  * Gather all bootstrap-related configuration data and compile it into
@@ -245,7 +246,12 @@ function findModelDefinitions(rootDir, sources) {
   var registry = {};
 
   sources.forEach(function(src) {
-    var srcDir = path.resolve(rootDir, src);
+    var srcDir = resolveSourceDir(rootDir, src);
+    if (!srcDir) {
+      debug('Skipping unknown module source dir %j', src);
+      return;
+    }
+
     var files = tryReadDir(srcDir);
     files
       .filter(function(f) {
@@ -267,6 +273,36 @@ function findModelDefinitions(rootDir, sources) {
   return registry;
 }
 
+function resolveSourceDir(rootDir, sourceDir) {
+  var srcDir = path.resolve(rootDir, sourceDir);
+  if (fs.existsSync(srcDir))
+    return srcDir;
+
+  // Handle module-relative path, e.g. `loopback/common/models`
+  var start = sourceDir.substring(0, 2);
+  if (start !== './' && start !== '..') {
+    // Module.globalPaths is a list of globally configured paths like
+    //   [ env.NODE_PATH values, $HOME/.node_modules, etc. ]
+    // Module._nodeModulePaths(rootDir) returns a list of paths like
+    //   [ rootDir/node_modules, rootDir/../node_modules, etc. ]
+    var modulePaths = Module.globalPaths
+      .concat(Module._nodeModulePaths(rootDir));
+
+    srcDir = modulePaths
+      .map(function(candidateDir) {
+        return path.join(candidateDir, sourceDir);
+      })
+      .filter(function(candidate) {
+        return fs.existsSync(candidate);
+      })
+      [0];
+    if (srcDir)
+      return srcDir;
+  }
+
+  return undefined;
+}
+
 function loadModelDefinition(rootDir, jsonFile) {
   var definition = require(jsonFile);
 

lib/executor.js

@@ -156,6 +156,10 @@ function defineModels(app, instructions) {
         throw new Error('Cannot configure unknown model ' + name);
       }
       debug('Configuring existing model %s', name);
+    } else if (isBuiltinLoopBackModel(app, data)) {
+      model = app.loopback[name];
+      assert(model, 'app.loopback[model] should have been defined');
+      debug('Configuring built-in LoopBack model %s', name);
     } else {
       debug('Creating new model %s %j', name, data.definition);
       model = app.loopback.createModel(data.definition);
@@ -176,6 +180,15 @@ function defineModels(app, instructions) {
   });
 }
 
+function isBuiltinLoopBackModel(app, data) {
+  // 1. Built-in models are exposed on the loopback object
+  if (!app.loopback[data.name]) return false;
+
+  // 2. Built-in models have a script file `loopback/{facet}/models/{name}.js`
+  return data.sourceFile &&
+    /node_modules\/loopback\/[^\/]+\/models\/[^\/]+\.js$/.test(data.sourceFile);
+}
+
 function forEachKeyedObject(obj, fn) {
   if(typeof obj !== 'object') return;
 

test/compiler.test.js

@@ -501,6 +501,30 @@ describe('compiler', function() {
       });
     });
 
+    it('supports sources relative to node_modules', function() {
+      appdir.createConfigFilesSync({}, {}, {
+        User: { dataSource: 'db' }
+      });
+
+      var instructions = boot.compile({
+        appRootDir: appdir.PATH,
+        modelSources: [
+          'loopback/common/models',
+          'loopback/common/dir-does-not-exist'
+        ]
+      });
+
+      expect(instructions.models).to.have.length(1);
+      expect(instructions.models[0]).to.eql({
+        name: 'User',
+        config: {
+          dataSource: 'db'
+        },
+        definition: require('loopback/common/models/user.json'),
+        sourceFile: require.resolve('loopback/common/models/user.js')
+      });
+    });
+
     it('handles model definitions with no code', function() {
       appdir.createConfigFilesSync({}, {}, {
         Car: { dataSource: 'db' }

test/executor.test.js

@@ -160,6 +160,22 @@ describe('executor', function() {
     expect(actual).to.equal('not attached');
   });
 
+  it('skips definition of already defined LoopBack models', function() {
+    var builtinModel = {
+      name: 'User',
+      definition: fs.readJsonFileSync(
+        require.resolve('loopback/common/models/user.json')
+      ),
+      config: { dataSource: 'db' },
+      sourceFile: require.resolve('loopback/common/models/user.js')
+    };
+    builtinModel.definition.redefined = true;
+
+    boot.execute(app, someInstructions({ models: [ builtinModel ] }));
+
+    expect(app.models.User.settings.redefined, 'redefined').to.not.equal(true);
+  });
+
   describe('with boot and models files', function() {
     beforeEach(function() {
       process.bootFlags = process.bootFlags || [];

test/fixtures/browser-app/model-config.json

@@ -1,4 +1,10 @@
 {
+  "_meta": {
+    "sources": [
+      "./models",
+      "loopback/common/models"
+    ]
+  },
   "Customer": {
     "dataSource": "db"
   }