Implement graphQL error handling

Author: khuongdn16

app/src/Dashboard/ProjectContainer.tsx

@@ -9,10 +9,6 @@ import Project from './Project.tsx';
 // 2) useQuery hook will update the data stored in Apollo Client's cache and automatically trigger child components rendering
 
 const ProjectContainer = () => {
-<<<<<<< HEAD
-=======
-
->>>>>>> typescript
   let myVar = {};
   // Need this for the individual user dasboard, for now, dashboard shows all projects from all users
   const userSSID = window.localStorage.getItem('ssid') || 'unavailable';

package.json

@@ -170,6 +170,7 @@
     "@types/enzyme": "^3.10.5",
     "@types/enzyme-adapter-react-16": "^1.0.6",
     "@types/jest": "^25.1.5",
+    "apollo": "^2.32.5",
     "babel-eslint": "^8.2.6",
     "babel-jest": "^25.2.4",
     "babel-loader": "^8.1.0",

server/graphQL/resolvers/mutation.js

@@ -1,130 +1,74 @@
-const { Tests, Projects } = require('../../models/reactypeModels');
-
+const { UserInputError } = require('apollo-server-express');
+const { Projects, Users } = require('../../models/reactypeModels');
 /*
 * resolvers are functions that handles graphQL requests. This file defines the logic for graphQL mutation requests
 * Link to Apollo Mutations:
 * https://www.apollographql.com/docs/apollo-server/data/resolvers/#defining-a-resolver
 */
 
-const Test = {
-  addTest: async (parent, args) => {
-    const resp = await Tests.create({ name: args.name, likes: args.likes });
-    console.log('Added test', resp);
-    if (resp) return { description: resp.name, id: resp._id, likes: args.likes };
-    return { description: 'Error creating test', id: 'unknown', likes: 0 };
-  },
-
-  updateTest: async (parent, args) => {
-    // console.log('args >>> ', args);
-    const filter = { _id: args.id };
-    const update = { name: args.name, likes: args.likes };
-    const options = { new: true };
-    const resp = await Tests.findOneAndUpdate(filter, update, options);
-
-    console.log('Updated database with', resp);
-
-    if (resp) return { description: resp.name, id: resp._id, likes: resp.likes };
-    return { description: 'Error updating', id: resp._id, likes: 0 };
-  },
-
-  deleteTest: async (parent, args) => {
-    const filter = { _id: args.id };
-    const resp = await Tests.deleteOne(filter);
-    if (resp) return { description: resp.name, id: resp._id, likes: 0 };
-    return { description: 'Error updating', likes: 0 };
-  },
-};
-
-
 const Project = {
   addLike: async (parent, { projId, likes }) => {
     const filter = { _id: projId };
     const update = { likes };
     const options = { new: true };
     const resp = await Projects.findOneAndUpdate(filter, update, options);
-
+  
     if (resp) {
       return ({
         name: resp.name,
         id: resp._id,
         userId: resp.userId,
-        username: resp.username,
         likes: resp.likes,
       });
     }
 
-    // TODO: Go back to this to see how to handle error later
-    return {
-      name: 'Error',
-      id: 'Error',
-      userId: 'Error',
-      username: 'Error',
-      likes: -1,
-    };
+    throw new UserInputError('Project is not found. Please try another project ID', {
+      argumentName: 'projId',
+    });
   },
 
   makeCopy: async (parent, { projId, userId, username }) => {
     const filter = { _id: projId };
     const target = await Projects.findOne(filter);
-    
-    // make a copy with the passed in userId
-    // IMPORTANT: DO NOT CHANGE copy.name, it will create a nother copy of the document with the origional project name.
-    const copy = {
-      name: target.name,   
-      project: target.project,
-      userId,
-      username,
-    };
-    
-    // IMPORTANT: MUST MAKE A DEEP COPY OF target.project, otherwise, field 'style' is lost during the copy process. See 'minimize' option in projectSchema
-    
-    const resp = await Projects.create(copy);
 
-    if (resp) {
-      return ({
-        name: resp.name,
-        id: resp._id,
-        userId: resp.userId,
-        username: resp.username,
-        likes: resp.likes,
+    if (!target) {
+      throw new UserInputError('Project is not found. Please try another project ID', {
+        argumentName: 'projId',
       });
     }
 
-    // TODO: Go back to this to see how to handle error later
-    return {
-      name: 'Error',
-      id: 'Error',
-      userId: 'Error',
-      username: 'Error',
-      likes: -1,
-    };
-  },
+    // check if user account exists
+    const user = await Users.findOne({ _id: userId });
+    console.log ('User >>> ', user);
+    if (user) {
+      // make a copy with the passed in userId
+      const copy = {
+        name: target.name,
+        project: target.project,
+        userId,
+        username,
+      };
 
-  deleteProject: async (parent, { projId }) => {
-    const filter = { _id: projId };
-    const options = { strict: true };
-    const resp = await Projects.findOneAndDelete(filter, options);
-    // console.log("resp", resp);
-    if (resp) {
-      return ({
-        name: resp.name,
-        likes: resp.likes,
-        id: resp._id,
-        userId: resp.userId,
-        username: resp.username,
-      });
+      // Make a copy of the requested project
+      const resp = await Projects.create(copy);
+      if (resp) {
+        return ({
+          name: resp.name,
+          id: resp._id,
+          userId: resp.userId,
+          username: resp.username,
+          likes: resp.likes,
+        })}
+
+      throw new UserInputError('Internal Server Error');
     }
-    return {
-      name: 'Error',
-      id: 'Error',
-      userId: 'Error',
-      username: 'Error',
-      likes: -1,
-    };
+
+    throw new UserInputError('User is not found. Please try another user ID', {
+      argumentName: 'userId',
+    });
   },
 };
 
 module.exports = {
-  TestMutation: Test,
   ProjectMutation: Project,
 };

server/graphQL/resolvers/query.js

@@ -1,32 +1,13 @@
-const { Tests, Projects, Users } = require('../../models/reactypeModels');
-
+const { UserInputError } = require('apollo-server-express');
+const { Projects } = require('../../models/reactypeModels');
 // Link to Apollo Query Types:
 // https://www.apollographql.com/docs/apollo-server/data/resolvers/#defining-a-resolver
 
-const Test = {
-
-  readTest: async (parent, args) => {
-    const resp = await Tests.findOne({ _id: args.id });
-    if (resp) return { description: resp.name, id: resp._id, likes: resp.likes };
-    return { description: 'Error reading', id: '0', likes: '0' };
-  },
-
-  readAllTests: async () => {
-    const resp = await Tests.find({});
-    // console.log('resp', resp);
-    if (resp) {
-      return resp.map(elem => ({ description: elem.name, id: elem._id, likes: elem.likes }));
-    }
-    // TODO: Go back to this to see how to handle error later
-    return [{ description: 'Error reading all tests', id: '0', likes: '0' }];
-  },
-
-};
-
 
 const Project = {
   getProject: async (parent, { projId }) => {
     const resp = await Projects.findOne({ _id: projId });
+    // console.log('getProject return >>> ', resp);
     if (resp) {
       return ({
         name: resp.name,
@@ -37,14 +18,10 @@ const Project = {
       });
     }
 
-    // TODO: Go back to this to see how to handle error later
-    return {
-      name: 'Error',
-      id: 'Error',
-      userId: 'Error',
-      username: 'Error',
-      likes: -1,
-    };
+    // resp is null if nothing is found based on the project ID
+    throw new UserInputError('Project is not found. Please try another project ID', {
+      argumentName: 'projId',
+    });
   },
 
   getAllProjects: async (parent, { userId }) => {
@@ -54,6 +31,10 @@ const Project = {
     if (userId) {
       // use loosely equal for the callback because there are some discrepancy between the type of userId from the db vs from the mutation query
       resp = resp.filter(proj => proj.userId == userId);
+      // if resp = [] after the filtering, this means the userId doesnt exisit in the database, throw error as follow
+      throw new UserInputError(`Project for userId: "${userId}". Please try another id`, {
+        argumentName: 'userId',
+      });
     }
 
     if (resp) {
@@ -66,20 +47,13 @@ const Project = {
       }));
     }
 
-    // TODO: Go back to this to see how to handle error later
-    return [{
-      name: 'Error',
-      id: 'Error',
-      userId: 'Error',
-      username: 'Error',
-      likes: -1,
-    }];
+    // resp is null, return error message 
+    throw new UserInputError('Internal Server Error');
   },
 
 
 };
 
 module.exports = {
-  TestQuery: Test,
   ProjectQuery: Project,
 };

server/graphQL/typeDefs.js

@@ -1,29 +1,10 @@
-
 const { gql } = require('apollo-server-express');
 
 // Link to defining a schema in Apollo:
 // https://www.apollographql.com/docs/apollo-server/schema/schema/
 // The schema specifies which queries and mutations are available for clients
 // to execute against your data graph.
 
-const Test = gql`
-
-  type Mutation {
-    addTest(name: String, likes: Int): Test
-    updateTest(id: ID, name: String, likes: Int): Test
-    deleteTest(id: ID): Test
-  }
-  type Test {
-    description: String
-    likes: Int
-    id: ID
-  }
-  type Query {
-    readTest(id: ID): Test
-    readAllTests: [Test]
-  }
-`;
-
 //NOTE: Project type does not return the detail of the project's components, but info needed for the dashboard
 const Project = gql`
 
@@ -48,6 +29,5 @@ const Project = gql`
 `;
 
 module.exports = {
-  typeDefsTest: Test,
   typeDefsProject: Project,
 };

server/server.js

@@ -59,9 +59,9 @@ GraphQl Router
 const { ApolloServer } = require('apollo-server-express');
 
 // Query resolvers
-const { TestQuery, ProjectQuery }  = require('./graphQL/resolvers/query');
+const { ProjectQuery } = require('./graphQL/resolvers/query');
 // Mutation resolvers
-const { TestMutation, ProjectMutation } = require('./graphQL/resolvers/mutation');
+const { ProjectMutation } = require('./graphQL/resolvers/mutation');
 
 // package resolvers into one variable to pass to Apollo Server
 const resolvers = {
@@ -70,15 +70,14 @@ const resolvers = {
 };
 
 // schemas used for graphQL
-const { typeDefsTest, typeDefsProject } = require('./graphQL/typeDefs');
+const { typeDefsProject } = require('./graphQL/typeDefs');
 
 // instantiate Apollo server and attach to Express server, mounted at 'http://localhost:PORT/graphql'
 const server = new ApolloServer({ typeDefs: typeDefsProject, resolvers });
 server.applyMiddleware({ app });
 /** ****************************************************************** */
 
 
-
 app.post(
   '/signup',
   userController.createUser,