In this workshop we'll learn how to build cloud-enabled web applications with React & AWS Amplify.
- Authentication
- REST API with a Lambda Function
- GraphQL API with AWS AppSync
- Adding Storage with Amazon S3
- Analytics
- Multiple Environments
- Deploying via the Amplify Console
- Removing / Deleting Services
To get started, we first need to create a new React project & change into the new directory using the Create React App CLI.
If you already have this installed, skip to the next step. If not, either install the CLI & create the app or create a new app using npx:
npm install -g create-react-app
create-react-app my-amplify-appOr use npx (npm 5.2 & later) to create a new app:
npx create-react-app my-amplify-appNow change into the new app directory & install the AWS Amplify & AWS Amplify React libraries:
cd my-amplify-app
npm install --save aws-amplify aws-amplify-react uuid
# or
yarn add aws-amplify aws-amplify-react uuidNext, we'll install the AWS Amplify CLI:
npm install -g @aws-amplify/cliNow we need to configure the CLI with our credentials:
amplify configureIf you'd like to see a video walkthrough of this configuration process, click here.
Here we'll walk through the amplify configure setup. Once you've signed in to the AWS console, continue:
- Specify the AWS Region: eu-central-1
- Specify the username of the new IAM user: amplify-workshop-user
In the AWS Console, click Next: Permissions, Next: Tags, Next: Review, & Create User to create the new IAM user. Then, return to the command line & press Enter.
- Enter the access key of the newly created user:
accessKeyId: (<YOUR_ACCESS_KEY_ID>)
secretAccessKey: (<YOUR_SECRET_ACCESS_KEY>) - Profile Name: amplify-workshop-user
amplify init- Enter a name for the project: amplifyreactapp
- Enter a name for the environment: local
- Choose your default editor: Visual Studio Code (or your default editor)
- Please choose the type of app that you're building javascript
- What javascript framework are you using react
- Source Directory Path: src
- Distribution Directory Path: build
- Build Command: npm run-script build
- Start Command: npm run-script start
- Do you want to use an AWS profile? Y
- Please choose the profile you want to use: amplify-workshop-user
Now, the AWS Amplify CLI has iniatilized a new project & you will see a new folder: amplify & a new file called aws-export.js in the src directory. These files hold your project configuration.
To add authentication, we can use the following command:
amplify add auth- Do you want to use default authentication and security configuration? Default configuration
- How do you want users to be able to sign in when using your Cognito User Pool? Username
- What attributes are required for signing up? Email (keep default)
Now, we'll run the push command and the cloud resources will be created in our AWS account.
amplify pushTo view the new Cognito authentication service at any time after its creation, go to the dashboard at https://console.aws.amazon.com/cognito/. Also be sure that your region is set correctly.
Now, our resources are created & we can start using them!
The first thing we need to do is to configure our React application to be aware of our new AWS Amplify project. We can do this by referencing the auto-generated aws-exports.js file that is now in our src folder.
To configure the app, open src/index.js and add the following code below the last import:
import Amplify from 'aws-amplify'
import config from './aws-exports'
Amplify.configure(config)Now, our app is ready to start using our AWS services.
To add authentication, we'll go into src/App.js and first import the withAuthenticator HOC (Higher Order Component) from aws-amplify-react:
import { withAuthenticator } from 'aws-amplify-react'Next, we'll wrap our default export (the App component) with the withAuthenticator HOC:
export default withAuthenticator(App, { includeGreetings: true })Now, we can run the app and see that an Authentication flow has been added in front of our App component. This flow gives users the ability to sign up & sign in.
To view the new user that was created in Cognito, go back to the dashboard at https://console.aws.amazon.com/cognito/. Also be sure that your region is set correctly.
We can access the user's info now that they are signed in by calling Auth.currentAuthenticatedUser().
import { Auth } from 'aws-amplify'
async componentDidMount() {
const user = await Auth.currentAuthenticatedUser()
console.log('user info:', user.signInUserSession.idToken.payload)
console.log('username:', user.username)
}The withAuthenticator component is a really easy way to get up and running with authentication, but in a real-world application we probably want more control over how our form looks & functions.
Let's look at how we might create our own authentication flow.
To get started, we would probably want to create input fields that would hold user input data in the state. For instance when signing up a new user, we would probably need 4 user inputs to capture the user's username, email, password, & phone number.
To do this, we could create some initial state for these values & create an event handler that we could attach to the form inputs:
// initial state
state = {
username: '', password: '', email: '', phone_number: ''
}
// event handler
onChange = (event) => {
this.setState({ [event.target.name]: event.target.value })
}
// example of usage with input
<input
name='username'
placeholder='username'
onChange={this.onChange}
/>We'd also need to have a method that signed up & signed in users. We can us the Auth class to do thi. The Auth class has over 30 methods including things like signUp, signIn, confirmSignUp, confirmSignIn, & forgotPassword. Thes functions return a promise so they need to be handled asynchronously.
// import the Auth component
import { Auth } from 'aws-amplify'
// Class method to sign up a user
signUp = async() => {
const { username, password, email, phone_number } = this.state
try {
await Auth.signUp({ username, password, attributes: { email, phone_number }})
} catch (err) {
console.log('error signing up user...', err)
}
}To add a REST API, we can use the following command:
amplify add apiAnswer the following questions
- Please select from one of the above mentioned services REST
- Provide a friendly name for your resource that will be used to label this category in the project: amplifyrestapi
- Provide a path, e.g. /items /pets
- Choose lambda source Create a new Lambda function
- Provide a friendly name for your resource that will be used to label this category in the project: amplifyrestapilambda
- Provide the Lambda function name: amplifyrestapilambda
- Please select the function template you want to use: Serverless express function (Integration with Amazon API Gateway)
- Do you want to edit the local lambda function now? Y
Update the existing `app.get('/pets') route with the following:
app.get('/pets', function(req, res) {
// Add your code here
// Return the API Gateway event and query string parameters for example
const pets = [
'Spike', 'Zeus', 'Butch'
]
res.json({
success: 'get call succeed!',
url: req.url,
pets
});
});- Restrict API access Y
- Who should have access? Authenticated users only
- What kind of access do you want for Authenticated users read/write
- Do you want to add another path? (y/N) N
Now the resources have been created & configured & we can push them to our account:
amplify pushNow that the API is created we can start sending requests to it & interacting with it.
Let's request some data from the API:
// src/App.js
import { API } from 'aws-amplify'
// create initial state
state = { pets: [] }
// fetch data at componentDidMount
componentDidMount() {
this.getData()
}
getData = async() => {
try {
const data = await API.get('amplifyrestapi', '/pets')
console.log('data from Lambda REST API: ', data)
this.setState({ pets: data.pets })
} catch (err) {
console.log('error fetching data..', err)
}
}
// implement into render method
{
this.state.pets.map((p, i) => (
<p key={i}>{p}</p>
))
}Next, let's configure the REST API to add another endpoint that will fetch data from an external resource.
First, we'll need to configure the API to know about the new path:
amplify configure api- Please select from one of the below mentioned services REST
- Please select the REST API you would want to update amplifyrestapi
- What would you like to do Add another path
- Provide a path (e.g., /items) /people
- Choose a Lambda source Use a Lambda function already added in the current Amplify project
- Choose the Lambda function to invoke by this path amplifyrestapilambda
- Restrict API access Yes
- Who should have access? Authenticated users only
- What kind of access do you want for Authenticated users read/write
- Do you want to add another path? No
The next thing we need to do is install axios in our Lambda function folder.
Navigate to amplify/backend/function/<FUNCTION_NAME>/src and install axios:
yarn add axios
# or
npm install axiosNext, in amplify/backend/function/<FUNCTION_NAME>/src/app.js, let's add a new endpoint that will fetch a list of people from the Star Wars API.
// require axios
var axios = require('axios')
// add new /people endpoint
app.get('/people', function(req, res) {
axios.get('https://swapi.co/api/people/')
.then(response => {
res.json({
people: response.data.results,
success: 'get call succeed!',
url: req.url
});
})
.catch(err => {
res.json({
error: 'error fetching data'
});
})
});Now we can add a new function called getPeople that will call this API:
componentDidMount() {
this.getData()
this.getPeople() // new
}
getPeople = async() => {
try {
const data = await API.get('amplifyrestapi', '/people')
console.log('data from new people endpoint:', data)
} catch (err) {
console.log('error fetching data..', err)
}
}To add a GraphQL API, we can use the following command:
amplify add apiAnswer the following questions
- Please select from one of the above mentioned services GraphQL
- Provide API name: GraphQLPets
- Choose an authorization type for the API API key
- Do you have an annotated GraphQL schema? N
- Do you want a guided schema creation? Y
- What best describes your project: Single object with fields (e.g. “Todo” with ID, name, description)
- Do you want to edit the schema now? (Y/n) Y
When prompted, update the schema to the following:
type Pet @model {
id: ID!
clientId: ID
name: String!
description: String!
}Next, let's push the configuration to our account:
amplify push- Do you want to generate code for your newly created GraphQL API Y
- Choose the code generation language target: javascript
- Enter the file name pattern of graphql queries, mutations and subscriptions: (src/graphql/**/*.js)
- Do you want to generate/update all possible GraphQL operations - queries, mutations and subscriptions? Y
- Enter maximum statement depth [increase from default if your schema is deeply nested] 2
To view the new AWS AppSync API at any time after its creation, go to the dashboard at https://console.aws.amazon.com/appsync. Also be sure that your region is set correctly.
In the AWS AppSync console, open your API & then click on Queries.
Execute the following mutation to create a new pet in the API:
mutation createPet {
createPet(input: {
name: "Zeus"
description: "Best dog in the western hemisphere"
}) {
id
}
}Now, let's query for the pet:
query listPets {
listPets {
items {
id
name
description
}
}
}We can even add search / filter capabilities when querying:
query listPets {
listPets(filter: {
description: {
contains: "dog"
}
}) {
items {
id
name
description
}
}
}Now that the GraphQL API is created we can begin interacting with it!
The first thing we'll do is perform a query to fetch data from our API.
To do so, we need to define the query, execute the query, store the data in our state, then list the items in our UI.
import React from 'react'
import './App.css'
// imports from Amplify library
import { API, graphqlOperation } from 'aws-amplify'
// import query
import { listPets as ListPets } from './graphql/queries'
class App extends React.Component {
// create initial state
state = {
pets: []
}
// execute the query in componentDidMount
async componentDidMount() {
try {
const pets = await API.graphql(graphqlOperation(ListPets))
console.log('pets:', pets)
this.setState({
pets: pets.data.listPets.items
})
} catch (err) {
console.log('error fetching pets...', err)
}
}
// implement into render method
render() {
return (
<div className="App">
<h2>Amplify App</h2>
{
this.state.pets.map((pet, index) => (
<div key={index}>
<h3>{pet.name}</h3>
<p>{pet.description}</p>
</div>
))
}
</div>
);
}
}
export default AppNow, let's look at how we can create mutations.
// import uuid to create a unique client ID
import uuid from 'uuid/v4'
// import the mutation
import { createPet as CreatePet } from './graphql/mutations'
const CLIENT_ID = uuid()
// update initial state
state = {
name: '', description: '', pets: []
}
createPet = async() => {
const { name, description } = this.state
if (name === '' || description === '') return
const pet = {
name, description, clientId: CLIENT_ID
}
const updatedPetArray = [...this.state.pets, pet]
this.setState({ pets: updatedPetArray })
try {
await API.graphql(graphqlOperation(CreatePet, { input: pet }))
console.log('item created!')
} catch (err) {
console.log('error creating pet...', err)
}
}
// change state then user types into input
onChange = (event) => {
this.setState({
[event.target.name]: event.target.value
})
}
// add UI with event handlers to manage user input
<input
name='name'
onChange={this.onChange}
value={this.state.name}
/>
<input
name='description'
onChange={this.onChange}
value={this.state.description}
/>
<button onClick={this.createPet}>Create Pet</button>Next, let's see how we can create a subscription to subscribe to changes of data in our API.
To do so, we need to define the subscription, listen for the subscription, & update the state whenever a new piece of data comes in through the subscription.
// import the subscription
import { onCreatePet as OnCreatePet } from './graphql/subscriptions'
// define the subscription in the class
subscription = {}
// subscribe in componentDidMount
componentDidMount() {
this.subscription = API.graphql(
graphqlOperation(OnCreatePet)
).subscribe({
next: (eventData) => {
console.log('eventData', eventData)
const pet = eventData.value.data.onCreatePet
if (pet.clientId === CLIENT_ID) return
const pets = [ ...this.state.pets, pet]
this.setState({ pets })
}
})
}
componentWillUnmount() {
this.subscription.unsubscribe()
}To add authorization to the API, we can re-configure the API to use our cognito identity pool. To do so, we can run amplify configure api:
amplify configure apiPlease select from one of the below mentioned services: GraphQL Choose an authorization type for the API: Amazon Cognito User Pool
Next, we'll run amplify push:
amplify push- Do you want to update code for your updated GraphQL API N
Now, we can only access the API with a logged in user.
Let's how how we can access the user's identity in the resolver. To do so, we'll first need to store the user's identity in the database table as userId & add a new index on the table to query for this user ID.
Adding an index to the table
Next, we'll want to add a new GSI (global secondary index) in the table. We do this so we can query on the index to gain new data access pattern.
To add the index, open the AppSync Console, choose your API & click on Data Sources. Next, click on the data source link.
From here, click on the Indexes tab & click Create index.
For the Partition key, input userId to create a userId-index Index name & click Create index.
Next, we'll update the resolver for adding pets & querying for pets.
In the folder amplify/backend/api/GraphQLPets/resolvers, create the following two resolvers:
Mutation.createPet.req.vtl & Query.listPets.req.vtl.
Mutation.createPet.req.vtl
$util.qr($context.args.input.put("createdAt", $util.time.nowISO8601()))
$util.qr($context.args.input.put("updatedAt", $util.time.nowISO8601()))
$util.qr($context.args.input.put("__typename", "Pet"))
$util.qr($context.args.input.put("userId", $ctx.identity.sub))
{
"version": "2017-02-28",
"operation": "PutItem",
"key": {
"id": $util.dynamodb.toDynamoDBJson($util.defaultIfNullOrBlank($ctx.args.input.id, $util.autoId()))
},
"attributeValues": $util.dynamodb.toMapValuesJson($context.args.input),
"condition": {
"expression": "attribute_not_exists(#id)",
"expressionNames": {
"#id": "id"
}
}
}Query.listPets.req.vtl
{
"version" : "2017-02-28",
"operation" : "Query",
"index" : "userId-index",
"query" : {
"expression": "userId = :userId",
"expressionValues" : {
":userId" : $util.dynamodb.toDynamoDBJson($ctx.identity.sub)
}
}
}Next, run the push command again to update the API:
amplify pushNow that we've added authorization to the API, we will have to log in if we would like to perform queries in the AppSync Console. To log in, find the
aws_user_pools_web_client_idfromaws-exports.js& log in using yourusername&password.
Now when we create new pets the userId field will be populated with the userId of the logged-in user.
When we query for the pets, we will only receive the data for the items that we created ourselves.
query listPets {
listPets {
items {
id
name
description
}
}
}Now let's say we want to define & use a custom GraphQL operation & create corresponding resolvers that do not yet exist? We can also do that using Amplify & the local environment.
Let's create a query & resolvers that will query for all pets in the API, similar to the functionality we had before changing the listPets resolver.
To do so, we need to do three things:
- Define the operations we'd like to have available in our schema (add queries, mutations, subscriptions to schema.graphql).
To do so, update amplify/backend/api/GraphQLPets/schema.graphql to the following:
type Pet @model {
id: ID!
clientId: ID
name: String!
description: String!
}
type ModelPetConnection {
items: [Pet]
nextToken: String
}
type Query {
listAllPets(limit: Int, nextToken: String): ModelPetConnection
}- Create the request & response mapping templates in amplify/backend/api/GraphQLPets/resolvers.
Query.listAllPets.req.vtl
{
"version" : "2017-02-28",
"operation" : "Scan",
"limit": $util.defaultIfNull(${ctx.args.limit}, 20),
"nextToken": $util.toJson($util.defaultIfNullOrBlank($ctx.args.nextToken, null))
}Query.listAllPets.res.vtl
{
"items": $util.toJson($ctx.result.items),
"nextToken": $util.toJson($util.defaultIfNullOrBlank($context.result.nextToken, null))
}- Update amplify/backend/api/GraphQLPets/stacks/CustomResources.json with the definition of the custom resource.
Update the Resources field in CustomResources.json to the following:
{
...rest of template,
"Resources": {
"QueryListAllPetsResolver": {
"Type": "AWS::AppSync::Resolver",
"Properties": {
"ApiId": {
"Ref": "AppSyncApiId"
},
"DataSourceName": "PetTable",
"TypeName": "Query",
"FieldName": "listAllPets",
"RequestMappingTemplateS3Location": {
"Fn::Sub": [
"s3://${S3DeploymentBucket}/${S3DeploymentRootKey}/resolvers/Query.listAllPets.req.vtl",
{
"S3DeploymentBucket": {
"Ref": "S3DeploymentBucket"
},
"S3DeploymentRootKey": {
"Ref": "S3DeploymentRootKey"
}
}
]
},
"ResponseMappingTemplateS3Location": {
"Fn::Sub": [
"s3://${S3DeploymentBucket}/${S3DeploymentRootKey}/resolvers/Query.listAllPets.res.vtl",
{
"S3DeploymentBucket": {
"Ref": "S3DeploymentBucket"
},
"S3DeploymentRootKey": {
"Ref": "S3DeploymentRootKey"
}
}
]
}
}
}
},
...rest of template,
}Now that everything has been updated, run the push command again:
amplify pushNow, we should have a new query available in our AppSync API to list all pets.
To add storage, we can use the following command:
amplify add storageAnswer the following questions
- Please select from one of the below mentioned services Content (Images, audio, video, etc.)
- Please provide a friendly name for your resource that will be used to label this category in the project: YOURAPINAME
- Please provide bucket name: YOURUNIQUEBUCKETNAME
- Who should have access: Auth users only
- What kind of access do you want for Authenticated users read/write
amplify pushNow, storage is configured & ready to use.
What we've done above is created configured an Amazon S3 bucket that we can now start using for storing items.
For example, if we wanted to test it out we could store some text in a file like this:
import { Storage } from 'aws-amplify'
// create function to work with Storage
addToStorage = () => {
Storage.put('javascript/MyReactComponent.js', `
import React from 'react'
const App = () => (
<p>Hello World</p>
)
export default App
`)
.then (result => {
console.log('result: ', result)
})
.catch(err => console.log('error: ', err));
}
// add click handler
<button onClick={this.addToStorage}>Add To Storage</button>This would create a folder called javascript in our S3 bucket & store a file called MyReactComponent.js there with the code we specified in the second argument of Storage.put.
To view the new S3 Bucket at any time after its creation, go to the dashboard at https://s3.console.aws.amazon.com/s3/home.
If we want to read everything from this folder, we can use Storage.list:
readFromStorage = () => {
Storage.list('javascript/')
.then(data => console.log('data from S3: ', data))
.catch(err => console.log('error'))
}If we only want to read the single file, we can use Storage.get:
readFromStorage = () => {
Storage.get('javascript/MyReactComponent.js')
.then(data => console.log('data from S3: ', data))
.catch(err => console.log('error'))
}If we wanted to pull down everything, we can use Storage.list:
readFromStorage = () => {
Storage.list('')
.then(data => console.log('data from S3: ', data))
.catch(err => console.log('error'))
}Working with images is also easy:
class S3ImageUpload extends React.Component {
onChange(e) {
const file = e.target.files[0];
Storage.put('example.png', file, {
contentType: 'image/png'
})
.then (result => console.log(result))
.catch(err => console.log(err));
}
render() {
return (
<input
type="file" accept='image'
onChange={(e) => this.onChange(e)}
/>
)
}
}We can even use the S3Album component, one of a few components in the AWS Amplify React library to create a preconfigured photo picker:
import { S3Album, withAuthenticator } from 'aws-amplify-react'
class App extends Component {
render() {
return (
<div className="App">
<S3Album path={''} picker />
</div>
);
}
}You can create multiple environments for your application in which to create & test out new features without affecting the main environment which you are working on.
When you create a new environment from an existing environment, you are given a copy of the entire backend application stack from the original project. When you make changes in the new environment, you are then able to test these new changes in the new environment & merge only the changes that have been made since the new environment was created back into the original environment.
Let's take a look at how to create a new environment. In this new environment, we'll re-configure the GraphQL Schema to have another field for the pet owner.
First, we'll initialize a new environment using amplify init:
amplify env add
> Do you want to use an existing environment? No
> Enter a name for the environment: apiupdate
> Do you want to use an AWS profile? Y
> Please choose the profile you want to use: amplify-workshop-profileOnce the new environment is initialized, we should be able to see some information about our environment setup by running:
amplify env list
| Environments |
| ------------ |
| local |
| *apiupdate |Now we can update the GraphQL Schema in amplify/backend/api/GraphQLPets/schema.graphql to the following (adding the owner field):
type Pet @model {
id: ID!
clientId: ID
name: String!
description: String!
owner: String
}Now, we can create this new stack by running amplify push:
amplify pushAfter we test it out, we can now merge it into our original local environment:
amplify env checkout localNext, run the status command:
amplify statusYou should now see an Update operation:
Current Environment: local
| Category | Resource name | Operation | Provider plugin |
| -------- | --------------- | --------- | ----------------- |
| Api | GraphQLPets | Update | awscloudformation |
| Auth | cognito75a8ccb4 | No Change | awscloudformation |To deploy the changes, run the push command:
amplify push- Do you want to update code for your updated GraphQL API? Y
- Do you want to generate GraphQL statements? Y
Now, the changes have been deployed & we can delete the apiupdate environment:
amplify env remove apiupdate
Do you also want to remove all the resources of the environment from the cloud? YNow, we should be able to run the list command & see only our main environment:
amplify env listFor hosting, we can use the Amplify Console to deploy the application.
The first thing we need to do is create a new GitHub repo for this project. Once we've created the repo, we'll copy the URL for the project to the clipboard & initialize git in our local project:
git init
git remote add origin [email protected]:username/project-name.git
git add .
git commit -m 'initial commit'
git push origin masterNext we'll visit the Amplify Console in our AWS account at https://eu-west-1.console.aws.amazon.com/amplify/home.
Here, we'll click Get Started to create a new deployment. Next, authorize Github as the repository service.
Next, we'll choose the new repository & branch for the project we just created & click Next.
In the next screen, we'll create a new role & use this role to allow the Amplify Console to deploy these resources & click Next.
Finally, we can click Save and Deploy to deploy our application!
Now, we can push updates to Master to update our application.
To add analytics, we can use the following command:
amplify add analyticsNext, we'll be prompted for the following:
- Provide your pinpoint resource name: amplifyanalytics
- Apps need authorization to send analytics events. Do you want to allow guest/unauthenticated users to send analytics events (recommended when getting started)? Y
- overwrite YOURFILEPATH-cloudformation-template.yml Y
Now that the service has been created we can now begin recording events.
To record analytics events, we need to import the Analytics class from Amplify & then call Analytics.record:
import { Analytics } from 'aws-amplify'
state = {username: ''}
async componentDidMount() {
try {
const user = await Auth.currentAuthenticatedUser()
this.setState({ username: user.username })
} catch (err) {
console.log('error getting user: ', err)
}
}
recordEvent = () => {
Analytics.record({
name: 'My test event',
attributes: {
username: this.state.username
}
})
}
<button onClick={this.recordEvent}>Record Event</button>If at any time, or at the end of this workshop, you would like to delete a service from your project & your account, you can do this by running the amplify remove command:
amplify remove auth
amplify pushIf you are unsure of what services you have enabled at any time, you can run the amplify status command:
amplify statusamplify status will give you the list of resources that are currently enabled in your app.
amplify delete