Merge pull request #4 from wajez/add-total-count

adding `Content-Total` to response of `list` and `showManyRelated` routes

README.md

@@ -134,7 +134,7 @@ app.use((err, req, res, next) => {
 
 That's all, we now have a functional REST API with the following routes and features:
 
-- `GET /users`: returns an array of users with format `{id, name, type, email, password}`. The query parameters `offset`, `limit` and `sort` can be used to sort by a field, specify the range of users to return. By default `offset = 0` and `limit = 100`. The query parameter `where` can be used to filter results.
+- `GET /users`: returns an array of users with format `{id, name, type, email, password}`. The response header `Content-Total` will contain the total count of results. The query parameters `offset`, `limit` and `sort` can be used to sort by a field, specify the range of users to return. By default `offset = 0` and `limit = 100`. The query parameter `where` can be used to filter results.
 - `GET /users/:id`: returns the single user having the `id` or `null` if not found.
 - `GET /users/:id/posts`: returns the list of posts of a specific user. The query parameters `offset`, `limit` and `sort` are supported.
 - `POST /users`: adds and returns a new user with the data in `req.body`. Giving the `posts` attribute as array of ids will update the corresponding posts to use the added user as their `writer`. if some of the posts are missing or have already a `writer`, an error is returned.
@@ -215,7 +215,7 @@ Let's start by listing the defined data types in this library.
 
 ### Query Types
 
-- `Query`: one of `CreateQuery`, `FindQuery`, `UpdateQuery`, and `RemoveQuery`.
+- `Query`: one of `CreateQuery`, `FindQuery`, `CountQuery`, `UpdateQuery`, and `RemoveQuery`.
 
 - `CreateQuery`: an object of format
 
@@ -244,6 +244,15 @@ Let's start by listing the defined data types in this library.
 }
 ```
 
+- `CountQuery`: an object of format
+
+```js
+{
+  type: 'count',
+  conditions: Object
+}
+```
+
 - `UpdateQuery`: an object of format
 
 ```js
@@ -489,6 +498,7 @@ Constructs a route that returns a list of the given model, then merges the `conv
 - The offset parameter is set from query parameter `offset`, same for `limit`, `sort`, and `where` parameters.
 - The `where` parameter is parsed as JSON and used as query conditions if given.
 - Default values for offset and limit are `0` and `100` respectively. No sort is defined by default.
+- The response header `Content-Total` will contain the total count of items matching the `where` conditions.
 
 ### show
 
@@ -706,6 +716,8 @@ Returns an express router containing all [`resource`](#resource) routes of all g
 
 # Development Notes
 
+- **1.4.0:** The response of `list` and `showRelated` contains now a header `Content-Total` equal to the total count of items; useful for pagination.
+
 - **1.3.0:** The query parameter `where` is now used to filter results on `list` and `show-many-related` routes.
 
 - **1.2.0:** `req.body` is now used to filter results on `list` and `show-many-related` routes.

package.json

@@ -1,6 +1,6 @@
 {
   "name": "wajez-api",
-  "version": "1.3.0",
+  "version": "1.4.1",
   "description": "REST API Development made easy.",
   "main": "src/index.js",
   "scripts": {

src/middlewares/basic.js

@@ -58,53 +58,65 @@ const setRelated = def('setRelated', {}, [$.String, T.Middleware],
 const getRelated = getParam('related')
 
 const setQuery = def('setQuery', {}, [$.Any, T.Middleware],
-  queryGetter => (req, res, next) => {
-    queryGetter(req)
-    .then(q => {
-      req.wz.query = q
+  queryGetter => async (req, res, next) => {
+    try {
+      req.wz.query = await queryGetter(req)
       next()
-    })
-    .catch(err => next(err))
+    } catch (err) {
+      next(err)
+    }
   }
 )
 
 const getQuery = getParam('query')
 
 const runQuery = def('run', {}, [T.MongooseModel, T.Middleware],
-  model => (req, res, next) => {
-    applyQuery(getQuery(req), model)
-    .then(data => {
-      req.wz.data = data
+  model => async (req, res, next) => {
+    try {
+      req.wz.data = await applyQuery(getQuery(req), model)
       next()
-    })
-    .catch(err => next(err))
+    } catch (err) {
+      next(err)
+    }
   }
 )
 
 const setData = def('setData', {}, [$.Any, T.Middleware],
-  dataGetter => (req, res, next) => {
-    dataGetter(req)
-    .then(data => {
-      req.wz.data = data
+  dataGetter => async (req, res, next) => {
+    try {
+      req.wz.data = await dataGetter(req)
       next()
-    })
-    .catch(err => next(err))
+    } catch (err) {
+      next(err)
+    }
   }
 )
 
 const getData = getParam('data')
 
-const convertData = def('convert', {}, [$.AnyFunction, T.Middleware],
-  converterGetter => (req, res, next) => {
-    converterGetter(req)
-    .then(fn => {
+const convertData = def('convertData', {}, [$.AnyFunction, T.Middleware],
+  converterGetter => async (req, res, next) => {
+    try {
       const data = getData(req)
       if (data == null)
         return next()
+      const fn = await converterGetter(req)
       req.wz.data = fn(data)
       next()
-    })
-    .catch(err => next(err))
+    } catch (err) {
+      next(err)
+    }
+  }
+)
+
+const setHeader = def('setHeader', {}, [$.String, $.AnyFunction, T.Middleware],
+  (headerName, valueGetter) => async (req, res, next) => {
+    try {
+      res.set(headerName, await valueGetter(req))
+      next()
+    } catch (err) {
+      next(err)
+    }
   }
 )
 
@@ -137,6 +149,7 @@ module.exports = {
   setData,
   getData,
   convertData,
+  setHeader,
   sendData,
   finish
 }

src/query.js

@@ -10,6 +10,8 @@ const applyQuery = def('applyQuery', {}, [T.Query, T.MongooseModel, $.Any],
       return applyCreateQuery(query, model)
     if (query.type === 'find')
       return applyFindQuery(query, model)
+    if (query.type === 'count')
+      return applyCountQuery(query, model)
     if (query.type === 'update')
       return applyUpdateQuery(query, model)
     if (query.type === 'remove')
@@ -28,6 +30,12 @@ const applyCreateQuery = def('applyCreateQuery', {}, [T.Query, T.MongooseModel,
   }
 )
 
+const applyCountQuery = def('applyCountQuery', {}, [T.Query, T.MongooseModel, $.Any],
+  async (query, model) => {
+    return model.count(query.conditions)
+  }
+)
+
 const applyUpdateQuery = def('applyUpdateQuery', {}, [T.Query, T.MongooseModel, $.Any],
   async (query, model) => {
     const old = await model.findOne(query.conditions)

src/routes/resource/list.js

@@ -2,12 +2,15 @@ const {$, def, S} = require('wajez-utils')
 const T = require('../../types')
 const helpers = require('../../helpers')
 const {get, extend} = require('../basic')
-const {onQuery, onRun, onConvert, onReadParams, beforeQuery} = require('../../actions')
+const {
+  onQuery, onRun, onConvert, onReadParams, beforeQuery, beforeSend
+} = require('../../actions')
 const {merge, applyConverter} = require('wajez-utils')
 const {
-  setQuery, runQuery, convertData, setRoute,
+  setQuery, runQuery, convertData, setRoute, setHeader,
   getOffset, getLimit, getSort, setModel, getWhere
 } = require('../../middlewares')
+const {applyQuery} = require('../../query')
 
 const list = (model, {converter, uri, actions} = {}) =>
   extend(get(helpers.uri(model), [
@@ -25,6 +28,13 @@ const list = (model, {converter, uri, actions} = {}) =>
       populate: []
     }))),
     onRun(runQuery(model)),
+    beforeSend(setHeader('Content-Total', async req =>
+      applyQuery({
+        type: 'count',
+        conditions: getWhere(req) || {}
+      }, model)
+    )),
+    beforeSend(setHeader('access-control-expose-headers', async () => 'Content-Total')),
     onConvert(convertData(helpers.routeConverter(model, converter || {})))
   ]), {uri, actions})
 

src/routes/resource/show-related.js

@@ -1,12 +1,13 @@
 const mongoose = require('mongoose')
-const {$, def, S, model} = require('wajez-utils')
+const {$, def, S, model, merge} = require('wajez-utils')
 const T = require('../../types')
 const helpers = require('../../helpers')
 const {get, extend} = require('../basic')
+const {applyQuery} = require('../../query')
 const {onQuery, onRun, beforeConvert, onConvert, onReadParams} = require('../../actions')
 const {
-  setQuery, runQuery, convertData, setData, setModel, getWhere,
-  setRoute, setRelated, getData, getOffset, getLimit, getSort
+  setQuery, runQuery, convertData, setData, setModel, getWhere, getQuery,
+  setRoute, setRelated, getData, getOffset, getLimit, getSort, setHeader
 } = require('../../middlewares')
 
 const showRelated = ({type, source, target}, config = {}) => {
@@ -54,29 +55,37 @@ const showManyRelated = def('showManyRelated', {}, [T.MongooseModel, T.MongooseM
       onReadParams(setModel(parent.modelName)),
       onReadParams(setRelated(child.modelName)),
       onReadParams(setRoute('show-many-related')),
-      onQuery(setQuery(async req => ({
-        type: 'find',
-        conditions: {_id: req.params.id},
-        projection: '_id',
-        options: {
-          limit: 1
-        },
-        populate: [{
-          path: field,
-          match: getWhere(req) || {},
-          select: null,
+      onQuery(setQuery(async req => {
+        const [parentItem] = await applyQuery({
+          type: 'find',
+          conditions: {_id: req.params.id},
+          projection: '_id ' + field,
+          options: { limit: 1 },
+          populate: []
+        }, parent)
+        if (!parentItem)
+          return {type: 'mock', data: []}
+        return {
+          type: 'find',
+          conditions: merge(getWhere(req) || {}, {_id: {$in: parentItem[field]}}),
+          projection: null,
           options: {
             skip: getOffset(req),
             limit: getLimit(req),
             sort: getSort(req)
-          }
-        }]
-      }))),
-      onRun(runQuery(parent)),
-      beforeConvert(setData(async req => {
-        const instance = getData(req)[0]
-        return !instance ? null : (instance[field] || null)
+          },
+          populate: []
+        }
+      })),
+      onRun(runQuery(child)),
+      onRun(setHeader('Content-Total', async req => {
+        const query = getQuery(req)
+        return applyQuery({
+          type: 'count',
+          conditions: query.conditions
+        }, child)
       })),
+      onRun(setHeader('access-control-expose-headers', async () => 'Content-Total')),
       onConvert(convertData(helpers.routeConverter(child, converter || {})))
     ]), {uri, actions})
 )

src/types/query.js

@@ -24,6 +24,11 @@ const FindQuery = _({
   }))
 })
 
+const CountQuery = _({
+  type: Enum('FindQueryType', ['count']),
+  conditions: QueryConditions
+})
+
 const RemoveQuery = _({
   type: Enum('RemoveQueryType', ['remove']),
   conditions: QueryConditions,
@@ -46,6 +51,7 @@ const UpdateQuery = _({
 const Query = Union('Query', [
   CreateQuery,
   FindQuery,
+  CountQuery,
   UpdateQuery,
   RemoveQuery,
   MockQuery

test/acceptance/one-to-many-relation.test.js

@@ -157,7 +157,7 @@ describe('Acceptance > One to Many Relation', () => {
   // check users1 posts
   it.get('/users/:id/posts', {
     params: () => users[1],
-    body: () => [posts[9], posts[0], posts[1]]
+    body: () => [posts[1], posts[9], posts[0]]
   })
   // check posts 9, 0 and 1 has user1 as writer
   it.get('/posts/:id/writer', {

test/acceptance/pagination.test.js

@@ -24,13 +24,18 @@ describe('Acceptance > Pagination and Sort', () => {
   it.get('/users?limit=200', {
     verify: (res, done) => {
       assert.lengthOf(res.body, 150)
+      assert.equal(res.get('Content-Total'), 150)
       users = res.body
       done()
     }
   })
 
   it.get('/users', {
-    body: () => users.slice(0, 100)
+    body: () => users.slice(0, 100),
+    verify: (res, done) => {
+      assert.equal(res.get('content-total'), 150)
+      done()
+    }
   })
 
   it.get('/users?offset=17&limit=24', {