processResponse option

epoberezkin · epoberezkin · commit 9783d4e74511 · 2016-04-30T01:11:50.000+01:00
diff --git a/README.md b/README.md
@@ -49,13 +49,14 @@ app.listen(3000);
 
 Now you can send POST requests to `/js` endpoint with the body containing the script and an optional data instance that will be processed by JSONScript interpreter. For example, with this request:
 
-```json
+```javascript
 {
   "script": {
     "res1": {
-      "$exec": "router",
-      "$method": "get",
+      "$exec": "router", // executor name can be changed in options
+      "$method": "get",  // $method can be get/post/put/delete
       "$args": { "path": "/resource/1" }
+      // method property in $args can be used instead of $method
     },
     "res2": {
       "$exec": "router",
@@ -85,6 +86,15 @@ the response will be a combination of two responses (both requests are processed
 }
 ```
 
+If option `processResponse: "body"` were used the result would have been:
+
+```javascript
+{
+  "res1": { /* response body 1 */ },
+  "res2": { /* response body 2 */ }
+}
+```
+
 JSONScript also supports sequential evaluation, conditionals, data manipulation etc. So you can implement an advanced logic in your script and it will be executed in the server without sending responses of individual requests to the client.
 
 See [JSONScript Language](https://github.com/JSONScript/jsonscript/blob/master/LANGUAGE.md) for more information.
@@ -116,13 +126,17 @@ Defaults:
 {
   routerExecutor: 'router',
   basePath: '',
+  processResponse: undefined,
   jsonscript: { strict: true },
   Promise: undefined
 }
 ```
 
 - _routerExecutor_: the name of the executor (the value of "$exec" keyword in the instruction) used to access Express router, `"router"` is used by default.
 - _basePath_: the path used as a prefix to paths in the script $exec instruction arguments.
+- _processResponse_: possible values:
+  - `"body"` - return only response body if status code is < 300, throw an exception otherwise.
+  - function - custom function to process the response object, can throw an exception or return the object to be used as the result.
 - _jsonscript_: options passed to JSONScript interpreter [jsonscript-js](https://github.com/JSONScript/jsonscript-js).
 - _Promise_: an optional Promise class, the native Promise is used by default.
 
diff --git a/index.js b/index.js
@@ -15,17 +15,10 @@ function jsonscriptExpress(app, options) {
     jsonscript: { strict: true },
     Promise: (typeof Promise !== 'undefined') && Promise
   });
+
+  var processResponce = processResponceFunc(options);
   var js = JSONScript(options.jsonscript);
-  METHODS.forEach(function (method) {
-    execRouter[method] = function(args) {
-      if (args.method && args.method != method) {
-        console.warn('method specified in args (' + args.method +
-                      ') is different from $method in instruction (' + method + '), used ' + method);
-      }
-      args.method = method;
-      return execRouter(args);
-    };
-  });
+  addExecutorMethods();
   js.addExecutor(options.routerExecutor, execRouter);
   evaluator.js = js;
 
@@ -41,7 +34,7 @@ function jsonscriptExpress(app, options) {
       .then(function (value) {
         res.send(value);
       }, function (err) {
-        res.status(err.errors ? 400 : 500)
+        res.status(err.errors ? 400 : err.statusCode || 500)
         .send({
           error: err.message,
           errors: err.errors
@@ -67,10 +60,53 @@ function jsonscriptExpress(app, options) {
     return new options.Promise(function (resolve, reject) {
       request.end(function (err, resp) {
         if (err) return reject(err);
-        resp = _.pick(resp, 'statusCode', 'headers', 'body');
-        resp.request = args;
-        resolve(resp);
+        resolve(processResponce(resp, args));
       });
     });
   }
+
+
+  function addExecutorMethods() {
+    METHODS.forEach(function (method) {
+      execRouter[method] = function(args) {
+        if (args.method && args.method != method) {
+          console.warn('method specified in args (' + args.method +
+                        ') is different from $method in instruction (' + method + '), used ' + method);
+        }
+        args.method = method;
+        return execRouter(args);
+      };
+    });
+  }
 }
+
+
+function processResponceFunc(options) {
+  return options.processResponse == 'body'
+          ? bodyProcessResponce
+          : typeof options.processResponse == 'function'
+            ? options.processResponse
+            : defaultProcessResponse;
+}
+
+
+function bodyProcessResponce(resp) {
+  if (resp.statusCode < 300) return resp.body;
+  throw new HttpError(resp);
+}
+
+
+function defaultProcessResponse(resp, args) {
+  resp = _.pick(resp, 'statusCode', 'headers', 'body');
+  resp.request = args;
+  return resp;
+}
+
+
+function HttpError(resp) {
+    this.message = resp.body ? JSON.stringify(resp.body) : 'Error';
+    this.statusCode = resp.statusCode;
+}
+
+HttpError.prototype = Object.create(Error.prototype);
+HttpError.prototype.constructor = HttpError;
diff --git a/package.json b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "jsonscript-express",
-  "version": "0.1.1",
+  "version": "0.2.0",
   "description": "Express middleware for batch processing using JSONScript",
   "main": "index.js",
   "scripts": {
diff --git a/spec/app.js b/spec/app.js
@@ -1,35 +1,39 @@
 'use strict';
 
 var express = require('express');
-var app = express();
 var bodyParser = require('body-parser');
 var jsonscript = require('..');
+var _ = require('lodash');
 
 
-app.use(bodyParser.json());
+module.exports = function createApp(jsonscriptOptions) {
+  var app = express();
 
-app.get('/api/:name/:id', function (req, res) {
-  var id = req.params.id;
-  send(res, req.params.name, id);
-});
+  app.use(bodyParser.json());
 
-app.post('/api/:name', function (req, res) {
-  var id = Date.now();
-  send(res, req.params.name, id, req.body);
-});
-
-app.post('/js', jsonscript(app, { basePath: '/api' }));
-
-function send(res, name, id, data) {
-  res.send({
-    name: name,
-    id: id,
-    info: 'resource ' + name + ' id ' + id,
-    data: data
+  app.get('/api/:name/:id', function (req, res) {
+    var id = req.params.id;
+    send(res, req.params.name, id);
   });
-}
 
+  app.post('/api/:name', function (req, res) {
+    var id = Date.now();
+    send(res, req.params.name, id, req.body);
+  });
 
-if (!module.parent) app.listen(3000);
-
-module.exports = app;
+  jsonscriptOptions = jsonscriptOptions
+                      ? _.extend({ basePath: '/api' }, jsonscriptOptions)
+                      : { basePath: '/api' };
+  app.post('/js', jsonscript(app, jsonscriptOptions));
+
+  function send(res, name, id, data) {
+    res.send({
+      name: name,
+      id: id,
+      info: 'resource ' + name + ' id ' + id,
+      data: data
+    });
+  }
+
+  return app;
+};
diff --git a/spec/handler.spec.js b/spec/handler.spec.js
@@ -1,11 +1,18 @@
 'use strict';
 
 var test = require('supertest');
-var app = require('./app');
+var createApp = require('./app');
 var assert = require('assert');
 
 
 describe('jsonscript handler', function() {
+  var app;
+
+  beforeEach(function() {
+    app = createApp();
+  });
+
+
   describe('single instruction without $method', function() {
     it('should process GET', function (done) {
       test(app)
@@ -177,6 +184,35 @@ describe('jsonscript handler', function() {
       });
     });
   });
+
+
+  describe('options', function() {
+    describe('processResponse: "body"', function() {
+      beforeEach(function() {
+        app = createApp({ processResponse: 'body' });
+      });
+
+      it('should return response body only', function (done) {
+        test(app)
+        .post('/js')
+        .set('Accept', 'application/json')
+        .send({
+          script: {
+            $exec: 'router',
+            $args: {
+              method: 'get',
+              path: '/object/1'
+            }
+          }
+        })
+        .expect(200)
+        .end(function (err, resp) {
+          assert.deepEqual(resp.body, { name: 'object', id: 1, info: 'resource object id 1' });
+          done();
+        });
+      });
+    });
+  });
 });
 
 

Original file line number	Diff line number	Diff line change
`@@ -1,6 +1,6 @@`
`1`	`1`	`{`
`2`	`2`	`"name": "jsonscript-express",`
`3`		`- "version": "0.1.1",`
	`3`	`+ "version": "0.2.0",`
`4`	`4`	`"description": "Express middleware for batch processing using JSONScript",`
`5`	`5`	`"main": "index.js",`
`6`	`6`	`"scripts": {`