feat(app): Support paginations

Facebook style pagination with connections on objects and relations
Tallyb · Nov 14, 2016 · 5ca2257 · 5ca2257
1 parent 5fea65d
commit 5ca2257
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Showing 6 changed files with 52 additions and 46 deletions.
diff --git a/.vscode/settings.json b/.vscode/settings.json
@@ -1,3 +1,6 @@
 // Place your settings in this file to overwrite default and user settings.
 {
+    "search.exclude": {
+        "**/out": true
+    }
 }
diff --git a/common/models/author.json b/common/models/author.json
@@ -37,8 +37,12 @@
             "type": "referencesMany",
             "model": "Author",
             "foreignKey": "friendIds"
+        },
+        "others": {
+            "type": "hasMany",
+            "model": "Author"
         }
     },
     "acls": [],
     "methods": {}
-}
+}
diff --git a/lib/execution.js b/lib/execution.js
@@ -4,7 +4,7 @@ var utils = require('./utils');
 
 function buildSelector(model, args) {
     let selector = {
-        where: {}
+        where: args.where || {}
     };
     const begin = utils.getId(args.after);
     const end = utils.getId(args.before);
@@ -24,20 +24,21 @@ function buildSelector(model, args) {
 }
 
 function findOne(model, obj, args, context) {
-    let id = obj ? obj.id : args.id;
+    let id = obj ? obj[model.getIdName()] : args.id;
     return model.findById(id);
 }
 
 function getCount(model, obj, args, context) {
-    return model.count();
+    return model.count(args.where);
 }
 
 function getFirst(model, obj, args) {
     return model.findOne({
-            order: model.getIdName() + (args.before ? ' DESC' : ' ASC')
+            order: model.getIdName() + (args.before ? ' DESC' : ' ASC'),
+            where: args.where
         })
         .then(res => {
-            return res.__data;
+            return res ? res.__data : {};
         });
 }
 
@@ -65,13 +66,21 @@ function findAll(model, obj, args, context) {
 }
 
 function findRelated(rel, obj, args, context) {
-    let selector = {};
-    if (!rel.multiple || _.isArray(obj[rel.keyFrom])) {
+    if (_.isArray(obj[rel.keyFrom])) {
+        return [];
+    }
+    if (rel.multiple) {
         // single relationship or set of items with ids included
-        return rel.modelTo.findByIds(obj[rel.keyFrom]);
+        args.where = {
+            [rel.keyTo]: obj[rel.keyFrom]
+        };
+        return findAll(rel.modelTo, obj, args, context);
+        //rel.modelTo.findByIds(obj[rel.keyFrom]);
     } else {
-        selector.where[rel.keyTo] = obj[rel.keyFrom];
-        return rel.modelTo.find(selector);
+
+        return findOne(rel.modelTo, obj, args, context);
+        //selector.where[rel.keyTo] = obj[rel.keyFrom];
+        //return rel.modelTo.find(selector);
     }
 }
 

diff --git a/lib/relations.js b/lib/relations.js
@@ -10,35 +10,25 @@ function isSimple(rel) {
     return rel.embed || !rel.multiple;
 }
 
-function isShared(rel) {
-    return rel.modelTo.shared;
+function sharedRelations(model) {
+    return _.pickBy(model.relations, rel => rel.modelTo.shared);
 }
 
 function typeDefs(model) {
-    return _.reduce(model.relations, (obj, rel, key) => {
-        if (isShared(rel)) {
-            obj = obj + ' \n ' + (isSimple(rel) ?
-                `${rel.name}: ${rel.modelTo.modelName}` :
-                `${rel.name} ${utils.PAGINATION}: [${connections.connectionTypeName(rel.modelTo)}]`);
-        }
+    return _.reduce(sharedRelations(model), (obj, rel, key) => {
+        obj = obj + ' \n ' + (isSimple(rel) ?
+            `${rel.name}: ${rel.modelTo.modelName}` :
+            `${rel.name} ${utils.PAGINATION}: ${connections.connectionTypeName(rel.modelTo)}`);
         return obj;
     }, '');
 }
 
 function resolvers(model) {
     let resolver = {};
-    _.forEach(model.relations, rel => {
-        if (isShared(rel)) {
-            if (isSimple(rel)) {
-                resolver[rel.name] = (obj, args, context) => {
-                    return execution.findEmbedded(rel, obj, args, context);
-                };
-            } else {
-                resolver[rel.name] = (obj, args, context) => {
-                    return execution.findRelated(rel, obj, args, context);
-                };
-            }
-        }
+    _.forEach(sharedRelations(model), rel => {
+        resolver[rel.name] = (obj, args, context) => {
+            return execution.findRelated(rel, obj, args, context);
+        };
     });
 
     return {

diff --git a/lib/utils.js b/lib/utils.js
@@ -2,8 +2,6 @@
 
 var _ = require('lodash');
 
-const PREFIX = 'connection.';
-
 const SCALARS = {
     number: 'Float',
     string: 'String',
@@ -13,7 +11,12 @@ const SCALARS = {
     object: 'JSON'
 };
 
-const PAGINATION = '(after: String, first: Int, before: String, last: Int)';
+const PAGINATION = '(where: JSON, after: String, first: Int, before: String, last: Int)';
+
+function toType(type) {
+    let scalar = SCALARS[type.toLowerCase().trim()];
+    return scalar ? scalar : type;
+}
 
 function base64(i) {
     return (new Buffer(i, 'ascii')).toString('base64');
@@ -23,6 +26,8 @@ function unbase64(i) {
     return (new Buffer(i, 'base64')).toString('ascii');
 }
 
+const PREFIX = 'connection.';
+
 /**
  * Creates the cursor string from an offset.
  * @param {String} id the id to convert
@@ -45,15 +50,9 @@ function getId(cursor) {
     if (cursor === undefined || cursor === null) {
         return null;
     }
-
     return cursorToId(cursor);
 }
 
-function toType(type) {
-    let scalar = SCALARS[type.toLowerCase().trim()];
-    return scalar ? scalar : type;
-}
-
 /**
  * Filter models to return shared models only
  * @param {Array<Model>} models all Loopback Models
@@ -82,7 +81,7 @@ module.exports = {
     sharedModels,
     sharedRelations,
     PAGINATION,
+    getId,
     idToCursor,
-    cursorToId,
-    getId
+    cursorToId
 };
diff --git a/test/pagination.spec.js b/test/pagination.spec.js
@@ -48,7 +48,6 @@ describe('Pagination', () => {
             .then(res => {
                 expect(res).to.have.status(200);
                 res = res.body.data;
-                console.log('RES', res);
                 expect(res.allNotes.edges.length).to.be.above(0);
             });
     });
@@ -79,7 +78,6 @@ describe('Pagination', () => {
             .then(res => {
                 expect(res).to.have.status(200);
                 res = res.body.data;
-                console.log('RES', res);
                 expect(res.allNotes.edges.length).to.be.above(0);
                 expect(res.allNotes.edges[0].node.id).to.be.above(4);
                 expect(res.allNotes.pageInfo.hasPreviousPage).to.be.true;
@@ -119,8 +117,11 @@ describe('Pagination', () => {
             .then(res => {
                 expect(res).to.have.status(200);
                 res = res.body.data;
-                console.log('RES', res);
-                expect(res.allAuthors.edges[0].node.Notes.length).to.be.above(1);
+                console.log('RES', res.allAuthors.edges[0]);
+
+                expect(res.allAuthors.edges[0].node.notes.Notes.length).to.be.above(0);
+                expect(res.allAuthors.edges[0].node.notes.totalCount).to.be.above(0);
+                expect(res.allAuthors.edges[0].cursor).not.to.be.empty;
             });
     });