👨‍💻 End-to-end Type-Safe GraphQL Workshop

Get introduced to the marvellous GraphQL universe! Discover all the benefits for adding End-to-end Type-Safety to your GraphQL App taking all the advantages of TypeScript, GraphQL & React working together. Apollo, auto-gen Types & Hooks would build the pillars of a SpaceX demo 🛰

🎯 Goals

• Understand Why, How & What's GraphQL
• Create a J/TS GraphQL Server
• Create a J/TS GraphQL Client
• Contribute with Open Source

🗓 Agenda

🚀 Server

• S0: JS GraphQL Server Demo
• S1: JS GraphQL Server
• S2: TS GraphQL Server

🌖 Client

• S0: JS REST Client
• S1: JS GraphQL Client
• S2: TS GraphQL Client

🛠 Requirements

👍 Essentials

• Node. Latest LTS Version (10.15.3).
• Git. Latest LTS Version (2.21.0).
• Github. You just need to create an account!

🤙 Nice to have

• VSCode. The futuristic J/TS IDE!
• CodeCopy. Copy to clipboard on markdown.

---

🌏 Intro

Open a terminal

Fork and clone this repository

git clone https://github.com/${👩‍💻👨‍💻}/e2e-ts-gql-workshop

Navigate to the created folder

cd e2e-ts-gql-workshop

---

🚀 Server

Time -0, it'll be time to liftoff creating (from scratch) a GraphQL Server. TypeDefs, resolvers & context will be the boosters of the GraphQL JS implementation. Then, we'll take all the advantages of having a strongly typed GraphQL Schema to auto-generate the TypeScript types based on our GraphQL type definitions!

Summary

• S0: JS GraphQL Server Demo
• S1: JS GraphQL Server
• S2: TS GraphQL Server

Step 0️⃣ JS GraphQL Server Demo

In this step will create a demo JS GraphQL Server based on mock data! Summary

• Create folder structure
• Implement JS GraphQL Server
• Run Server

📦 Create folder structure

👉 Checkout first step

git checkout server-step-0

👍 Create server folder

mkdir server

👌 Create index.js inside the server folder

cd server
touch index.js

🎮 Implement JS GraphQL Server

Let's implement a demo GraphQL server in our index.js

👉 Declare typeDefs

const typeDefs = gql`
  # Entry Points
  type Query {
    launches: [Launch]
    launch(id: Int!): Launch
  }

  # Types
  type Launch {
    flight_number: Int!
    mission_name: String!
    details: String
    links: LaunchLinks
    rocket: LaunchRocket
  }
  type LaunchLinks {
    flickr_images: [String]
  }
  type LaunchRocket {
    rocket_name: String!
  }
`;

👉 Declare resolvers

const resolvers = {
  Query: {
    launches: (obj, args, context) => launches,
    launch: (obj, args, context) =>
      launches.find(launch => args.id === launch.flight_number)
  }
};

👉 Declare server

const server = new ApolloServer({
  typeDefs,
  resolvers
});

👉 Call server

server.listen().then(({ url }) => console.log(`🚀 Server ready at: ${url}`));

👍 Import mock data

const launches = [...]

👌 Add dependencies

const gql = require("graphql-tag");
const { ApolloServer } = require("apollo-server");

⚡️ Run Server

👉 Install dependencies

npm install graphql apollo-server

👍 Run server

node ./index.js

👌 Explore GraphQL API http://localhost:4000/

Well done 💪, commit your changes and let's get our hands dirty!

Step 1️⃣ JS GraphQL Server

In this step we will connect the server with a database and we will implement an underfecthing solution

Summary

• Explore the DB
• Create DB connector
• Adapt server & resolvers
• Underfetching implementation

🧐 Explore the DB

Let's discover how to access to SpaceX real data 🔎

👉 Open Humongous

👉 Login on Get Started and choose your fav MongoDB hosting provider

👉 Paste the SpaceX Public DB link

mongodb+srv://public:spacex@spacex-gcp-gpg0u.gcp.mongodb.net/spacex-api

👍 Click Next & Create Project

👌 Explore all the data collections

🕹 Create DB connector

Now, we are gonna get rid of the mocks to use real data 🔥

👉 Create db.js file

touch db.js

👉 Connect to DB

const url =
  "mongodb+srv://public:spacex@spacex-gcp-gpg0u.gcp.mongodb.net/spacex-api";

const getDB = async () => {
  const client = await MongoClient.connect(url, {
    poolSize: 20,
    useNewUrlParser: true
  });

  return client.db("spacex-api");
};

module.exports = {
  getDB
};

👍 Add mongodb dependendy

const MongoClient = require("mongodb");

👌 Install mongodb dependency

npm install mongodb

💫 Adapt server & resolvers

👉 Adapt our server on index.js replacing the current definition with:

(async () => {
  const db = await getDB();

  const server = new ApolloServer({
    typeDefs,
    resolvers,
    context: { db }
  });

  server.listen().then(({ url }) => console.log(`🚀 Server ready at ${url}`));
})();

👉 Import the DB

const { getDB } = require("./db");

👉 Implement resolvers replacing the current with:

const resolvers = {
  Query: {
    launches: async (obj, args, context) => {
      const data = await context.db
        .collection("launch")
        .find()
        .limit(10)
        .toArray();
      return data;
    },
    launch: async (obj, { flight_number }, context) => {
      const [data] = await context.db
        .collection("launch")
        .find({ flight_number })
        .limit(1)
        .toArray();
      return data;
    }
  }
};

👉 Remove launches on index.js

👍 Run server

node ./index.js

👌 Explore explore real data through the GraphQL API (refresh your browser) http://localhost:4000/

♻️ Underfetching implementation

👉 Add rocket to LaunchRocket

type LaunchRocket {
  rocket_name: String!
  rocket: Rocket
}

👉 Include the Rocket type

type Rocket {
  id: ID!
  name: String
  description: String
  cost_per_launch: Int
}

👍 Add the LaunchRocket resolver

const resolvers = {
  Query: {...},
  LaunchRocket: {
    rocket: async (obj, args, context) => {
      console.log("obj: ", obj);
      const [data] = await context.db
        .collection("rocket")
        .find({ id: obj.rocket_id })
        .limit(1)
        .toArray();
      return data;
    }
  }
}

👌 Run the server & explore real data (refresh your browser)

node ./index.js

Look 👀 what you're getting on obj when asking for launches { rocket { rocket { ... } } } (don't forget to remove the console.log)

2/3 ✅, creating APIs has never been easier, commit your changes and let's move on to the last step!

Step 2️⃣ TS GraphQL Server

In this step will auto-generate TypeScript types based on our GraphQL implementation to make our API type safe

Sumary

• Explore API & Codebase
• Evolve the API
• Generate TS types
• Evolve Safely the API

🤔 Explore API & Codebase

👉 Checkout

git checkout server-step-2

👉 Install dependencies & run the server

cd server
npm install
npm start

👉 Explore the API http://localhost:4000

👍 Explore the codebase

👌 Try to understand how this query is being resolved

{
  history(id: 17) {
    title
    flight {
      mission_name
      rocket {
        rocket {
          name
          cost_per_launch
        }
      }
    }
  }
}

🎸 Evolve the API

👍 Add to Rocket typeDefs rocketByName

extend type Query {
  ...
  rocketByName(name: String!): Rocket
}

👌 Add it resolver

rocketByName: async (obj, { name }, context) => {
  const [data] = await context.db
    .collection(collection)
    .find({ name })
    .limit(1)
    .toArray();
  return data;
};

👍 Run server

node ./index.js

👌 Explore GraphQL API testing the new evolution (refresh your browser) http://localhost:4000/

If everything went well, commit your changes!

🎶 Generate TS types

👉 Checkout

git checkout server-step-3

👉 Install dependencies & run the server

npm install
npm run dev

👉 Create codegen.yml file

touch codegen.yml

👉 Include the configuration

schema: src/schema/**/*.ts
overwrite: true
watch: true
require:
  - ts-node/register
generates:
  ./src/types/types.d.ts:
    config:
      contextType: ./context#MyContext
    plugins:
      - typescript-common
      - typescript-server
      - typescript-resolvers

Indentation here is crucial!

👉 Install codegen dependencies

npm install graphql-code-generator@0.16.0 graphql-codegen-typescript-common@0.16.0 graphql-codegen-typescript-resolvers@0.16.0 graphql-codegen-typescript-server@0.16.0

👉 Install dependencies

npm install

👍 Open a terminal and run

npm run dev

👌 Explore the API http://localhost:4000

👍 Open another terminal and run

npm run generate

👌 Explore types/types.d.ts file

Commit your changes and let's wrap this up!

🎻 Evolve Safely the API

👉 Add again rocketByName into the Rocket typeDefs

  extend type Query {
    ...
    rocketByName(name: String!): Rocket
  }

👉 Explore the types/types.d.ts file changes

👉 Add again it resolver

rocketByNome: async (obj, { nome }, context) => {
  const [data] = await context.db
    .collection(collection)
    .find({ nome })
    .limit(1)
    .toArray();
  return data;
};

👉 Type your rocket's resolvers

const Query: QueryResolvers.Resolvers = {
  ...
}

👍 Import the QueryResolvers type definitions

import { QueryResolvers } from "../../types/types";

👌 Fix all the erros that you could find with the help of TypeScript!

Step 👽 Create a REST API based on GraphQL

👉 Checkout

git checkout server-step-5

👉 Install dependencies & run the server

npm install
npm run dev

👍 Explore the GraphQL API http://localhost:4000/graphql 🤙 Explore the REST API http://localhost:4000/rest

👌 Explore the codebase Take a look at the servers folder, excluding that folder eveything is same than last step!

GraphQL 💜 REST

🎉 You're just finished all GraphQL Server steps, let's now learn about GraphQL Clients!

---

🌖 Client

Approaching landing... we will create a React-Apollo client in JS (using hooks, of course). Later on we will evolve it safely generating the TypeScript types from our GraphQL documents!

Summary

• S0: JS REST Client
• S1: JS GraphQL Client
• S2: TS GraphQL Client

Step 0️⃣ JS REST Client

Summary

• Create folder structure
• Setup Suspense
• Fetch data from REST

📦 Create folder structure

👉 Checkout first step

git checkout client-step-0

👍 Install create-react-app

npm install --global create-react-app

👌 Create client folder

create-react-app client

⭐️ Setup Suspense

👉 Add Suspense into your index.js ReactDom.render:

ReactDOM.render(
  <Suspense fallback="Loading...">
    <App />
  </Suspense>,
  document.getElementById("root")
);

👉 Import Suspense:

import React, { Suspense } from "react";

💫 Fetch data from REST

👉 Change your App component as follow:

function App() {
  const launchesPast = useFetch("https://api.spacex.land/rest/launches-past");
  return (
    <React.Fragment>
      {launchesPast.map(({ mission_name, details, links, rocket }) => (
        <div key={String(mission_name)}>
          <h3>
            🛰 {mission_name} 🚀 {rocket.name}
          </h3>
          <p>{details}</p>
          <img src={links.flickr_images[0]} width="200" />
        </div>
      ))}
    </React.Fragment>
  );
}

👉 Import useFetch

import useFetch from "fetch-suspense";

👉 Install fetch-suspense

cd client
npm install fetch-suspense

👍 Install dependencies & run the client

npm install
npm start

👌 Explore the Client http://localhost:3000

Step 1️⃣ JS GraphQL Client

Summary

• Setup GraphQL Client
• Fetch data from GraphQL

🌟 Setup GraphQL Client

👉 Create on index.js a new Apollo Client

const client = new ApolloClient({
  uri: "http://api.spacex.land/graphql"
});

👉 Include ApolloProvider

ReactDOM.render(
  <ApolloProvider client={client}>
    <Suspense fallback="Loading...">
      <App />
    </Suspense>
  </ApolloProvider>,
  document.getElementById("root")
);

👍 Import dependencies

import { ApolloProvider } from "react-apollo-hooks";
import ApolloClient from "apollo-boost";

👌 Install dependencies

npm install react-apollo-hooks apollo-boost graphql

⚡️ Fetch data from GraphQL

👉 Write on 'App.js' the GraphQL query

const query = gql`
  query getLaunches {
    launchesPast {
      mission_name
      details
      links {
        flickr_images
      }
      rocket {
        name: rocket_name
      }
    }
  }
`;

👉 Add useQuery to fetch data from the GraphQL API

const launchesPastRest = useFetch("https://api.spacex.land/rest/launches-past");
const {
  data: { launchesPast = [] }
} = useQuery(query);

👉 Import useQuery

import { useQuery } from "react-apollo-hooks";
import gql from "graphql-tag";

👉 Run the client again

npm start

👍 Explore the Client http://localhost:3000

👌 Open your browser inspector tool and give a 👀 to both size & time GraphQL-REST calls!

Commit your changes! It's time to finish the workshop off 💪

Step 2️⃣ TS GraphQL Client

Summary

• Evolve the Client
• Generate TS types
• Evolve Safely the Client

🎸 Evolve the Client

👉 Checkout last step

git checkout client-step-2

👉 Include launch_success field into our query

const query = gql`
  query getLaunches {
    launchesPast {
      mission_name
      details
      links {
        flickr_images
      }
      rocket {
        name: rocket_name
      }
      launch_success
    }
  }
`;

👉 Remove useFetch call and log the query to verify that launch_success is there

function App() {
  // const launchesPast = useFetch("https://api.spacex.land/rest/launches-past");
  const {
    data: { launchesPast }
  } = useQuery(query);

  console.log("launchesPast", launchesPast)

  return (...);
}

👍 Display launch_success

function App() {
  const {
    data: { launchesPast = [] }
  } = useQuery(query);
  return (
    <React.Fragment>
      {launchesPast.map(
        ({ mission_name, details, links, rocket, launch_success }) => (
          <div key={String(mission_name)}>
            <h3>
              🛰 {mission_name} 🚀 {rocket.
              }
            </h3>
            <p>{details}</p>
            <h3>Success: {launch_success ? "✅" : "❌"}</h3>
            <img src={links.flickr_images[0]} width="200" />
          </div>
        )
      )}
    </React.Fragment>
  );
}

👌 Explore the Client to see the new field http://localhost:3000

🎶 Generate TS types

👉 Create codegen.yml file

touch codegen.yml

👉 Include the configuration

schema: https://api.spacex.land/graphql
documents:
  - src/**/*.tsx
overwrite: true
watch: true
generates:
  ./src/types/types.d.ts:
    plugins:
      - typescript-common
      - typescript-client

👉 Install codegen dependencies

npm install graphql-code-generator@0.16.0 graphql-codegen-typescript-common@0.16.0 graphql-codegen-typescript-client@0.16.0

👉 Install dependencies

npm install

👍 Open a terminal and run

npm start

👌 Explore the Client http://localhost:3000

👍 Open another terminal and run

npm run generate

👌 Explore types/types.d.ts file

Fantastic, we are almost done. Don't forget to commit the changes!

🎻 Evolve Safely the Client

👉 Type your returned data

const {
  data: { launchesPast }
} = useQuery<GetLaunches.Query>(query);

👉 Import GetLaunches type definition

import { GetLaunches } from "../types";

👍 Add the ships field to the query

const query = gql`
  query getLaunches {
    launchesPast {
      # ...
      ships {
        id
        name
        port: home_port
        image
      }
    }
  }
`;

👌 Display the ships with the help of TypeScript auto-completion!

return (
  <React.Fragment>
    {launchesPast.map(
      ({ ..., ships }) => (
          // ...
          {ships.map(({ id, name, port, image }) => (
            <div key={id}>
              <h3>
                ⛴ {name} 🌊 {port}
              </h3>
              <img src={image} alt="" width={200} />
            </div>
          ))}
        </div>
      )
    )}
  </React.Fragment>
);

Step 👽 Introspect API from the IDE

👉 Install Apollo GraphQL VS Code extension

👍 Create apollo.config.js file:

module.exports = {
  client: {
    service: {
      url: "https://api.spacex.land/graphql"
    }
  }
};

👌 Press Ctrl + Space Bar inside your query 🤯

🎊 You're just finished all GraphQL Client steps, hoping that you've enjoyed & learned something new!

😄 Thanks for coming

Don't hesitate to contact @swcarlosrj if you'd have any question!