Merge pull request #2559 from strongloop/deprecate/getCurrentContext

Deprecate current-context API

Gruntfile.js

@@ -44,9 +44,6 @@ module.exports = function(grunt) {
       common: {
         src: ['common/**/*.js']
       },
-      browser: {
-        src: ['browser/**/*.js']
-      },
       server: {
         src: ['server/**/*.js']
       },
@@ -59,7 +56,6 @@ module.exports = function(grunt) {
       lib: ['lib/**/*.js'],
       common: ['common/**/*.js'],
       server: ['server/**/*.js'],
-      browser: ['browser/**/*.js'],
       test: ['test/**/*.js']
     },
     watch: {

browser/current-context.js

@@ -1,17 +0,0 @@
-// Copyright IBM Corp. 2015,2016. All Rights Reserved.
-// Node module: loopback
-// This file is licensed under the MIT License.
-// License text available at https://opensource.org/licenses/MIT
-
-var g = require('strong-globalize')();
-
-module.exports = function(loopback) {
-  loopback.getCurrentContext = function() {
-    return null;
-  };
-
-  loopback.runInContext =
-  loopback.createContext = function() {
-    throw new Error(g.f('Current context is not supported in the browser.'));
-  };
-};

lib/current-context.js

@@ -0,0 +1,78 @@
+// Copyright IBM Corp. 2015,2016. All Rights Reserved.
+// Node module: loopback
+// This file is licensed under the MIT License.
+// License text available at https://opensource.org/licenses/MIT
+
+var juggler = require('loopback-datasource-juggler');
+var remoting = require('strong-remoting');
+var LoopBackContext = require('loopback-context');
+var deprecated = require('depd')('loopback');
+var g = require('strong-globalize')();
+
+module.exports = function(loopback) {
+
+  /**
+   * Get the current context object. The context is preserved
+   * across async calls, it behaves like a thread-local storage.
+   *
+   * @returns {ChainedContext} The context object or null.
+   */
+  loopback.getCurrentContext = function() {
+    // NOTE(bajtos) LoopBackContext.getCurrentContext is overriden whenever
+    // the context changes, therefore we cannot simply assign
+    // LoopBackContext.getCurrentContext() to loopback.getCurrentContext()
+    deprecated(g.f('%s is deprecated. See %s for more details.',
+      'loopback.getCurrentContext()',
+      'https://docs.strongloop.com/display/APIC/Using%20current%20context'));
+    return LoopBackContext.getCurrentContext();
+  };
+
+  juggler.getCurrentContext =
+  remoting.getCurrentContext = loopback.getCurrentContext;
+
+  /**
+   * Run the given function in such way that
+   * `loopback.getCurrentContext` returns the
+   * provided context object.
+   *
+   * **NOTE**
+   *
+   * The method is supported on the server only, it does not work
+   * in the browser at the moment.
+   *
+   * @param {Function} fn The function to run, it will receive arguments
+   * (currentContext, currentDomain).
+   * @param {ChainedContext} context An optional context object.
+   *   When no value is provided, then the default global context is used.
+   */
+  loopback.runInContext = function(fn, ctx) {
+    deprecated(g.f('%s is deprecated. See %s for more details.',
+      'loopback.runInContext()',
+      'https://docs.strongloop.com/display/APIC/Using%20current%20context'));
+    return LoopBackContext.runInContext(fn, ctx);
+  };
+
+  /**
+   * Create a new LoopBackContext instance that can be used
+   * for `loopback.runInContext`.
+   *
+   * **NOTES**
+   *
+   * At the moment, `loopback.getCurrentContext` supports
+   * a single global context instance only. If you call `createContext()`
+   * multiple times, `getCurrentContext` will return the last context
+   * created.
+   *
+   * The method is supported on the server only, it does not work
+   * in the browser at the moment.
+   *
+   * @param {String} scopeName An optional scope name.
+   * @return {ChainedContext} The new context object.
+   */
+  loopback.createContext = function(scopeName) {
+    deprecated(g.f('%s is deprecated. See %s for more details.',
+      'loopback.createContext()',
+      'https://docs.strongloop.com/display/APIC/Using%20current%20context'));
+    return LoopBackContext.createContext(scopeName);
+  };
+};

lib/loopback.js

@@ -222,7 +222,7 @@ loopback.template = function(file) {
   });
 };
 
-require('../server/current-context')(loopback);
+require('../lib/current-context')(loopback);
 
 /**
  * Create a named vanilla JavaScript class constructor with an attached

package.json

@@ -36,7 +36,6 @@
     "bcryptjs": "^2.1.0",
     "body-parser": "^1.12.0",
     "canonical-json": "0.0.4",
-    "continuation-local-storage": "^3.1.3",
     "cookie-parser": "^1.3.4",
     "debug": "^2.1.2",
     "depd": "^1.0.0",
@@ -45,6 +44,7 @@
     "express": "^4.12.2",
     "inflection": "^1.6.0",
     "loopback-connector-remote": "^1.0.3",
+    "loopback-context": "^1.0.0",
     "loopback-phase": "^1.2.0",
     "nodemailer": "^2.5.0",
     "nodemailer-stub-transport": "^1.0.0",
@@ -100,7 +100,6 @@
   "browser": {
     "express": "./lib/browser-express.js",
     "./lib/server-app.js": "./lib/browser-express.js",
-    "./server/current-context.js": "./browser/current-context.js",
     "connect": false,
     "nodemailer": false,
     "supertest": false,

server/current-context.js

@@ -1,143 +0,0 @@
-// Copyright IBM Corp. 2015,2016. All Rights Reserved.
-// Node module: loopback
-// This file is licensed under the MIT License.
-// License text available at https://opensource.org/licenses/MIT
-
-var juggler = require('loopback-datasource-juggler');
-var remoting = require('strong-remoting');
-var cls = require('continuation-local-storage');
-var domain = require('domain');
-
-module.exports = function(loopback) {
-
-  /**
-   * Get the current context object. The context is preserved
-   * across async calls, it behaves like a thread-local storage.
-   *
-   * @returns {ChainedContext} The context object or null.
-   */
-  loopback.getCurrentContext = function() {
-    // A placeholder method, see loopback.createContext() for the real version
-    return null;
-  };
-
-  /**
-   * Run the given function in such way that
-   * `loopback.getCurrentContext` returns the
-   * provided context object.
-   *
-   * **NOTE**
-   *
-   * The method is supported on the server only, it does not work
-   * in the browser at the moment.
-   *
-   * @param {Function} fn The function to run, it will receive arguments
-   * (currentContext, currentDomain).
-   * @param {ChainedContext} context An optional context object.
-   *   When no value is provided, then the default global context is used.
-   */
-  loopback.runInContext = function(fn, context) {
-    var currentDomain = domain.create();
-    currentDomain.oldBind = currentDomain.bind;
-    currentDomain.bind = function(callback, context) {
-      return currentDomain.oldBind(ns.bind(callback, context), context);
-    };
-
-    var ns = context || loopback.createContext('loopback');
-
-    currentDomain.run(function() {
-      ns.run(function executeInContext(context) {
-        fn(ns, currentDomain);
-      });
-    });
-  };
-
-  /**
-   * Create a new LoopBackContext instance that can be used
-   * for `loopback.runInContext`.
-   *
-   * **NOTES**
-   *
-   * At the moment, `loopback.getCurrentContext` supports
-   * a single global context instance only. If you call `createContext()`
-   * multiple times, `getCurrentContext` will return the last context
-   * created.
-   *
-   * The method is supported on the server only, it does not work
-   * in the browser at the moment.
-   *
-   * @param {String} scopeName An optional scope name.
-   * @return {ChainedContext} The new context object.
-   */
-  loopback.createContext = function(scopeName) {
-    // Make the namespace globally visible via the process.context property
-    process.context = process.context || {};
-    var ns = process.context[scopeName];
-    if (!ns) {
-      ns = cls.createNamespace(scopeName);
-      process.context[scopeName] = ns;
-      // Set up loopback.getCurrentContext()
-      loopback.getCurrentContext = function() {
-        return ns && ns.active ? ns : null;
-      };
-
-      chain(juggler);
-      chain(remoting);
-    }
-    return ns;
-  };
-
-  /**
-   * Create a chained context
-   * @param {Object} child The child context
-   * @param {Object} parent The parent context
-   * @private
-   * @constructor
-   */
-  function ChainedContext(child, parent) {
-    this.child = child;
-    this.parent = parent;
-  }
-
-  /**
-   * Get the value by name from the context. If it doesn't exist in the child
-   * context, try the parent one
-   * @param {String} name Name of the context property
-   * @returns {*} Value of the context property
-   * @private
-   */
-  ChainedContext.prototype.get = function(name) {
-    var val = this.child && this.child.get(name);
-    if (val === undefined) {
-      return this.parent && this.parent.get(name);
-    }
-  };
-
-  ChainedContext.prototype.set = function(name, val) {
-    if (this.child) {
-      return this.child.set(name, val);
-    } else {
-      return this.parent && this.parent.set(name, val);
-    }
-  };
-
-  ChainedContext.prototype.reset = function(name, val) {
-    if (this.child) {
-      return this.child.reset(name, val);
-    } else {
-      return this.parent && this.parent.reset(name, val);
-    }
-  };
-
-  function chain(child) {
-    if (typeof child.getCurrentContext === 'function') {
-      var childContext = new ChainedContext(child.getCurrentContext(),
-        loopback.getCurrentContext());
-      child.getCurrentContext = function() {
-        return childContext;
-      };
-    } else {
-      child.getCurrentContext = loopback.getCurrentContext;
-    }
-  }
-};

server/middleware/context.js

@@ -3,55 +3,13 @@
 // This file is licensed under the MIT License.
 // License text available at https://opensource.org/licenses/MIT
 
-var loopback = require('../../lib/loopback');
+var deprecated = require('depd')('loopback');
+var g = require('strong-globalize')();
+var perRequestContext = require('loopback-context').perRequest;
 
-module.exports = context;
+module.exports = function() {
-
+  deprecated(g.f('%s middleware is deprecated. See %s for more details.',
-var name = 'loopback';
+    'loopback#context',
-
+    'https://docs.strongloop.com/display/APIC/Using%20current%20context'));
-/**
+  return perRequestContext.apply(this, arguments);
- * Context middleware.
+};
- * ```js
- * var app = loopback();
- * app.use(loopback.context(options);
- * app.use(loopback.rest());
- * app.listen();
- * ```
- * @options {Object} [options] Options for context
- * @property {String} name Context scope name.
- * @property {Boolean} enableHttpContext Whether HTTP context is enabled.  Default is false.
- * @header loopback.context([options])
- */
-
-function context(options) {
-  options = options || {};
-  var scope = options.name || name;
-  var enableHttpContext = options.enableHttpContext || false;
-  var ns = loopback.createContext(scope);
-
-  // Return the middleware
-  return function contextHandler(req, res, next) {
-    if (req.loopbackContext) {
-      return next();
-    }
-
-    loopback.runInContext(function processRequestInContext(ns, domain) {
-      req.loopbackContext = ns;
-
-      // Bind req/res event emitters to the given namespace
-      ns.bindEmitter(req);
-      ns.bindEmitter(res);
-
-      // Add req/res event emitters to the current domain
-      domain.add(req);
-      domain.add(res);
-
-      // Run the code in the context of the namespace
-      if (enableHttpContext) {
-        // Set up the transport context
-        ns.set('http', {req: req, res: res});
-      }
-      next();
-    });
-  };
-}

test/access-token.test.js

@@ -477,7 +477,8 @@ describe('app.enableAuth()', function() {
   it('stores token in the context', function(done) {
     var TestModel = loopback.createModel('TestModel', { base: 'Model' });
     TestModel.getToken = function(cb) {
-      cb(null, loopback.getCurrentContext().get('accessToken') || null);
+      var ctx = loopback.getCurrentContext();
+      cb(null, ctx && ctx.get('accessToken') || null);
     };
     TestModel.remoteMethod('getToken', {
       returns: { arg: 'token', type: 'object' },