Add path resolution to get helper

refs #5993

- deps: jsonpath@0.2.0
- adds `resolvePaths` method
- supports handlebars style arrays with `.[]`
- supports shorthand post.tags and post.author for common usecases
- adds more tests & improves existing ones

core/server/helpers/get.js

@@ -6,12 +6,20 @@ var _               = require('lodash'),
     Promise         = require('bluebird'),
     errors          = require('../errors'),
     api             = require('../api'),
+    jsonpath        = require('jsonpath'),
     resources,
+    pathAliases,
     get;
 
 // Endpoints that the helper is able to access
 resources =  ['posts', 'tags', 'users'];
 
+// Short forms of paths which we should understand
+pathAliases     = {
+    'post.tags': 'post.tags[*].slug',
+    'post.author': 'post.author.slug'
+};
+
 /**
  * ## Is Browse
  * Is this a Browse request or a Read request?
@@ -29,6 +37,34 @@ function isBrowse(context, options) {
     return browse;
 }
 
+/**
+ * ## Resolve Paths
+ * Find and resolve path strings
+ *
+ * @param {Object} data
+ * @param {String} value
+ * @returns {String}
+ */
+function resolvePaths(data, value) {
+    var regex = /\{\{(.*?)\}\}/g;
+
+    value = value.replace(regex, function (match, path) {
+        var result;
+
+        // Handle aliases
+        path = pathAliases[path] ? pathAliases[path] : path;
+        // Handle Handlebars .[] style arrays
+        path = path.replace(/\.\[/g, '[');
+
+        // Do the query, and convert from array to string
+        result = jsonpath.query(data, path).join(',');
+
+        return result;
+    });
+
+    return value;
+}
+
 /**
  * ## Parse Options
  * Ensure options passed in make sense
@@ -46,6 +82,10 @@ function parseOptions(data, options) {
         options.author = options.author.slug;
     }
 
+    if (_.isString(options.filter)) {
+        options.filter = resolvePaths(data, options.filter);
+    }
+
     return options;
 }
 

core/test/unit/server_helpers/get_spec.js

@@ -9,17 +9,20 @@ var should         = require('should'),
 // Stuff we are testing
     handlebars     = hbs.handlebars,
     helpers        = require('../../../server/helpers'),
-    api            = require('../../../server/api');
+    api            = require('../../../server/api'),
+
+    sandbox = sinon.sandbox.create();
 
 describe('{{#get}} helper', function () {
-    var sandbox;
+    var fn, inverse;
 
     before(function () {
         utils.loadHelpers();
     });
 
     beforeEach(function () {
-        sandbox = sinon.sandbox.create();
+        fn = sandbox.spy();
+        inverse = sandbox.spy();
     });
 
     afterEach(function () {
@@ -31,18 +34,19 @@ describe('{{#get}} helper', function () {
     });
 
     describe('posts', function () {
-        var testPostsArr = [
-            {id: 1, title: 'Test Post 1', author: 'cameron'},
-            {id: 2, title: 'Test Post 2', author: 'cameron', featured: true},
+        var browseStub, readStub, testPostsArr = [
+            {id: 1, title: 'Test Post 1', author: {slug: 'cameron'}},
+            {id: 2, title: 'Test Post 2', author: {slug: 'cameron'}, featured: true},
             {id: 3, title: 'Test Post 3', tags: [{slug: 'test'}]},
             {id: 4, title: 'Test Post 4'}
-        ];
+        ],
+            meta = {pagination: {}};
         beforeEach(function () {
-            var browseStub = sandbox.stub(api.posts, 'browse'),
-                readStub = sandbox.stub(api.posts, 'read');
+            browseStub = sandbox.stub(api.posts, 'browse');
+            readStub = sandbox.stub(api.posts, 'read');
 
             browseStub.returns(new Promise.resolve({posts: testPostsArr}));
-            browseStub.withArgs({limit: '3'}).returns(new Promise.resolve({posts: testPostsArr.slice(0, 3)}));
+            browseStub.withArgs({limit: '3'}).returns(new Promise.resolve({posts: testPostsArr.slice(0, 3), meta: meta}));
             browseStub.withArgs({limit: '1'}).returns(new Promise.resolve({posts: testPostsArr.slice(0, 1)}));
             browseStub.withArgs({tag: 'test'}).returns(new Promise.resolve({posts: testPostsArr.slice(2, 3)}));
             browseStub.withArgs({tag: 'none'}).returns(new Promise.resolve({posts: []}));
@@ -52,9 +56,6 @@ describe('{{#get}} helper', function () {
         });
 
         it('should handle default browse posts call', function (done) {
-            var fn = sinon.spy(),
-                inverse = sinon.spy();
-
             helpers.get.call(
                 {},
                 'posts',
@@ -71,9 +72,6 @@ describe('{{#get}} helper', function () {
         });
 
         it('should handle browse posts call with limit 3', function (done) {
-            var fn = sinon.spy(),
-                inverse = sinon.spy();
-
             helpers.get.call(
                 {},
                 'posts',
@@ -90,9 +88,6 @@ describe('{{#get}} helper', function () {
         });
 
         it('should handle browse posts call with limit 1', function (done) {
-            var fn = sinon.spy(),
-                inverse = sinon.spy();
-
             helpers.get.call(
                 {},
                 'posts',
@@ -109,9 +104,6 @@ describe('{{#get}} helper', function () {
         });
 
         it('should handle browse posts call with limit 1', function (done) {
-            var fn = sinon.spy(),
-                inverse = sinon.spy();
-
             helpers.get.call(
                 {},
                 'posts',
@@ -128,9 +120,6 @@ describe('{{#get}} helper', function () {
         });
 
         it('should handle browse post call with explicit tag', function (done) {
-            var fn = sinon.spy(),
-                inverse = sinon.spy();
-
             helpers.get.call(
                 {},
                 'posts',
@@ -146,9 +135,6 @@ describe('{{#get}} helper', function () {
         });
 
         it('should handle browse post call with relative tag', function (done) {
-            var fn = sinon.spy(),
-                inverse = sinon.spy();
-
             helpers.get.call(
                 {},
                 'posts',
@@ -164,9 +150,6 @@ describe('{{#get}} helper', function () {
         });
 
         it('should handle browse post call with explicit author', function (done) {
-            var fn = sinon.spy(),
-                inverse = sinon.spy();
-
             helpers.get.call(
                 {},
                 'posts',
@@ -182,9 +165,6 @@ describe('{{#get}} helper', function () {
         });
 
         it('should handle browse post call with relative author', function (done) {
-            var fn = sinon.spy(),
-                inverse = sinon.spy();
-
             helpers.get.call(
                 {},
                 'posts',
@@ -200,9 +180,6 @@ describe('{{#get}} helper', function () {
         });
 
         it('should handle browse post call with featured:true', function (done) {
-            var fn = sinon.spy(),
-                inverse = sinon.spy();
-
             helpers.get.call(
                 {},
                 'posts',
@@ -218,9 +195,6 @@ describe('{{#get}} helper', function () {
         });
 
         it('should handle read post by id call', function (done) {
-            var fn = sinon.spy(),
-                inverse = sinon.spy();
-
             helpers.get.call(
                 {},
                 'posts',
@@ -237,9 +211,6 @@ describe('{{#get}} helper', function () {
         });
 
         it('should handle empty result set', function (done) {
-            var fn = sinon.spy(),
-                inverse = sinon.spy();
-
             helpers.get.call(
                 {},
                 'posts',
@@ -257,9 +228,6 @@ describe('{{#get}} helper', function () {
 
     describe('general error handling', function () {
         it('should return an error for an unknown resource', function (done) {
-            var fn = sinon.spy(),
-                inverse = sinon.spy();
-
             helpers.get.call(
                 {},
                 'magic',
@@ -276,9 +244,6 @@ describe('{{#get}} helper', function () {
         });
 
         it('should handle error from the API', function (done) {
-            var fn = sinon.spy(),
-                inverse = sinon.spy();
-
             helpers.get.call(
                 {},
                 'posts',
@@ -295,9 +260,6 @@ describe('{{#get}} helper', function () {
         });
 
         it('should show warning for call without any options', function (done) {
-            var fn = sinon.spy(),
-                inverse = sinon.spy();
-
             helpers.get.call(
                 {},
                 'posts'
@@ -309,4 +271,89 @@ describe('{{#get}} helper', function () {
             }).catch(done);
         });
     });
+
+    describe('path resolution', function () {
+        var browseStub, readStub, data = {
+            post: {id: 3, title: 'Test 3', author: {slug: 'cameron'}, tags: [{slug: 'test'}, {slug: 'magic'}]}
+        };
+
+        beforeEach(function () {
+            browseStub = sandbox.stub(api.posts, 'browse').returns(new Promise.resolve());
+            readStub = sandbox.stub(api.posts, 'read').returns(new Promise.resolve());
+        });
+
+        it('should resolve post.tags alias', function (done) {
+            helpers.get.call(
+                data,
+                'posts',
+                {hash: {filter: 'tags:[{{post.tags}}]'}, fn: fn, inverse: inverse}
+            ).then(function () {
+                browseStub.firstCall.args.should.be.an.Array.with.lengthOf(1);
+                browseStub.firstCall.args[0].should.be.an.Object.with.property('filter');
+                browseStub.firstCall.args[0].filter.should.eql('tags:[test,magic]');
+
+                done();
+            }).catch(done);
+        });
+
+        it('should resolve post.author alias', function (done) {
+            helpers.get.call(
+                data,
+                'posts',
+                {hash: {filter: 'author:{{post.author}}'}, fn: fn, inverse: inverse}
+            ).then(function () {
+                browseStub.firstCall.args.should.be.an.Array.with.lengthOf(1);
+                browseStub.firstCall.args[0].should.be.an.Object.with.property('filter');
+                browseStub.firstCall.args[0].filter.should.eql('author:cameron');
+
+                done();
+            }).catch(done);
+        });
+
+        it('should resolve basic path', function (done) {
+            helpers.get.call(
+                data,
+                'posts',
+                {hash: {filter: 'id:-{{post.id}}'}, fn: fn, inverse: inverse}
+            ).then(function () {
+                    browseStub.firstCall.args.should.be.an.Array.with.lengthOf(1);
+                    browseStub.firstCall.args[0].should.be.an.Object.with.property('filter');
+                    browseStub.firstCall.args[0].filter.should.eql('id:-3');
+
+                    done();
+                }).catch(done);
+        });
+
+        it('should handle arrays the same as handlebars', function (done) {
+            var tpl = handlebars.compile('{{post.tags.[0].slug}}'),
+                output = tpl(data);
+
+            helpers.get.call(
+                data,
+                'posts',
+                {hash: {filter: 'tags:{{post.tags.[0].slug}}'}, fn: fn, inverse: inverse}
+            ).then(function () {
+                browseStub.firstCall.args.should.be.an.Array.with.lengthOf(1);
+                browseStub.firstCall.args[0].should.be.an.Object.with.property('filter');
+                browseStub.firstCall.args[0].filter.should.eql('tags:' + output);
+
+                done();
+            }).catch(done);
+        });
+
+        it('should output nothing if path does not resolve', function (done) {
+            helpers.get.call(
+                data,
+                'posts',
+                {hash: {filter: 'id:{{post.thing}}'}, fn: fn, inverse: inverse}
+            ).then(function () {
+                    browseStub.firstCall.args.should.be.an.Array.with.lengthOf(1);
+                    browseStub.firstCall.args[0].should.be.an.Object.with.property('filter');
+                    browseStub.firstCall.args[0].filter.should.eql('id:');
+
+                    done();
+                }).catch(done);
+        });
+    });
 });
+

package.json

@@ -46,6 +46,7 @@
     "html-to-text": "1.3.2",
     "intl": "1.0.0",
     "intl-messageformat": "1.1.0",
+    "jsonpath": "0.2.0",
     "knex": "0.7.3",
     "lodash": "3.10.1",
     "moment": "2.10.6",