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![© 2018, Amazon Web Services, Inc. or its Affiliates. All rights reserved.
Describe your data with a schema
type Tweet {
id: ID
body: String
date: Date
Author: User
}
type User {
id: ID
username: String
tweets: [Tweet]
}](https://image.slidesharecdn.com/adityatalk-181011164912/85/AppSync-in-real-world-pitfalls-unexpected-benefits-lessons-learnt-10-320.jpg)
![© 2018, Amazon Web Services, Inc. or its Affiliates. All rights reserved.
Queries and Mutations
type Query {
getTweet(id: ID): Tweet
allTweets: [Tweet]
}
type Mutation {
newTweet(body: String): Tweet
newUser(username: String): User
}](https://image.slidesharecdn.com/adityatalk-181011164912/85/AppSync-in-real-world-pitfalls-unexpected-benefits-lessons-learnt-11-320.jpg)
![© 2018, Amazon Web Services, Inc. or its Affiliates. All rights reserved.
Ask for exactly the data you need
query {
getUser(id: "123") {
username
tweets {
body
date
}
}
}
{
"username": "...",
"tweets": [
{
"body": "...",
"date": "..."
},
{
"body": "...",
"date": "..."
},
]
}](https://image.slidesharecdn.com/adityatalk-181011164912/85/AppSync-in-real-world-pitfalls-unexpected-benefits-lessons-learnt-12-320.jpg)
![© 2018, Amazon Web Services, Inc. or its Affiliates. All rights reserved.
Subscriptions
type Subscription {
userTweeted(id: ID): Tweet
@aws_subscribe(mutations: ["newTweet"])
}
Subscription {
userTweeted(id: "jdoe123") {
body
}
}](https://image.slidesharecdn.com/adityatalk-181011164912/85/AppSync-in-real-world-pitfalls-unexpected-benefits-lessons-learnt-13-320.jpg)
![© 2018, Amazon Web Services, Inc. or its Affiliates. All rights reserved.
#set($moistures = [])
#foreach($reading in ${context.args.moisture})
$util.qr($moistures.add($util.dynamodb.toMapValues($reading)))
#end
#set($pHs = [])
#foreach($reading in ${context.args.pH})
$util.qr($pHs.add($util.dynamodb.toMapValues($reading)))
#end
{
"version": "2018-05-29",
"operation": "BatchPutItem",
"tables": {
"moistureReadings": $util.toJson($moistures),
"pHReadings": $util.toJson($pHs)
}
}
input Moisture {
timestamp: String
value: Float
}
input pH {
timestamp: String
value: Float
}
mutation {
record(
moisture: [Moisture],
pH: [pH]
)
}
DynamoDB Multi-Table Batch PutItem](https://image.slidesharecdn.com/adityatalk-181011164912/85/AppSync-in-real-world-pitfalls-unexpected-benefits-lessons-learnt-19-320.jpg)
![© 2018, Amazon Web Services, Inc. or its Affiliates. All rights reserved.
Field Resolvers
type Post {
id: ID!
text: String
comments: [Comment]
}
type Comment {
postId: ID!
commentId: String!
text: String
}
Posts
id text
Comments
postId commentId text](https://image.slidesharecdn.com/adityatalk-181011164912/85/AppSync-in-real-world-pitfalls-unexpected-benefits-lessons-learnt-20-320.jpg)
![© 2018, Amazon Web Services, Inc. or its Affiliates. All rights reserved.
Field Resolvers
type Post {
id: ID!
text: String
comments: [Comment]
}
type Comment {
postId: ID!
commentId: String!
text: String
}
{
"version": "2017-02-28",
"operation": "Query",
"query": {
"expression": "postId = :postId",
"expresssionValues": {
":postId": { "S": "$context.source.id" }
}
}
}](https://image.slidesharecdn.com/adityatalk-181011164912/85/AppSync-in-real-world-pitfalls-unexpected-benefits-lessons-learnt-21-320.jpg)
![© 2018, Amazon Web Services, Inc. or its Affiliates. All rights reserved.
type Mutation {
addPost(id: ID!, title: String!): Post!
@aws_auth(cognito_groups: [“Bloggers", "Admins"])
}
Using Cognito Groups](https://image.slidesharecdn.com/adityatalk-181011164912/85/AppSync-in-real-world-pitfalls-unexpected-benefits-lessons-learnt-25-320.jpg)
Uploaded byAWS User Group Bengaluru
AppSync in real world - pitfalls, unexpected benefits & lessons learnt
The document provides an overview of AWS AppSync, a serverless GraphQL service for building data-driven applications with real-time and offline capabilities. It describes features such as data fetching, validation, authentication, and integration with various data sources like DynamoDB and Lambda while outlining how to define schemas, queries, mutations, and subscriptions. Additionally, it touches on the advantages and disadvantages of using AppSync for application development.
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AppSync in real world - pitfalls, unexpected benefits & lessons learnt
- 1. © 2018, AmazonWeb Services, Inc. or its Affiliates. All rights reserved. BENGALURU
- 2. © 2018, AmazonWeb Services, Inc. or its Affiliates. All rights reserved. AppSync in the Real World ADITHYA REDDY | SDE @ BRANCH FINANCIAL
- 3. © 2018, AmazonWeb Services, Inc. or its Affiliates. All rights reserved. What is AppSync • “Build data-driven apps with real-time and offline capabilities” • Fully managed, serverless GraphQL service • Client SDKs + Offline programming model
- 4. © 2018, AmazonWeb Services, Inc. or its Affiliates. All rights reserved. Clients iOS Android JS Managed Datastores RDS DynamoDB Neptune Middle-Tier K8s Docker VMs Storage Streams Search Logging Auth ETL Analytics Validation Logic You operate You don’t operate
- 5. © 2018, AmazonWeb Services, Inc. or its Affiliates. All rights reserved. Clients iOS Android JS Managed Datastores RDS DynamoDB Neptune Middle-Tier K8s Docker VMs S3 Kinesis ES Service CloudWatch Cognito EMR Athena Validation Logic You operate You don’t operate
- 6. © 2018, AmazonWeb Services, Inc. or its Affiliates. All rights reserved. Hub for all your managed services • Provide a single unified API layer over all your data sources. • Fetch, shape, transform, and aggregate data into exactly what the client asked for. • Replace the middle layer of (most) apps.
- 7. © 2018, AmazonWeb Services, Inc. or its Affiliates. All rights reserved. • Validating requests and payloads • Authentication • Fine-grained permissions • Access control What AppSync can do • Fetching/writing data to/from data sources • Real-time updates • Offline with optimistic UI updates • Resolving data conflicts
- 8. © 2018, AmazonWeb Services, Inc. or its Affiliates. All rights reserved. GraphQL 101
- 9. © 2018, AmazonWeb Services, Inc. or its Affiliates. All rights reserved. A strongly typed, declarative query language for APIs. graphql.org
- 10. © 2018, AmazonWeb Services, Inc. or its Affiliates. All rights reserved. Describe your data with a schema type Tweet { id: ID body: String date: Date Author: User } type User { id: ID username: String tweets: [Tweet] }
- 11. © 2018, AmazonWeb Services, Inc. or its Affiliates. All rights reserved. Queries and Mutations type Query { getTweet(id: ID): Tweet allTweets: [Tweet] } type Mutation { newTweet(body: String): Tweet newUser(username: String): User }
- 12. © 2018, AmazonWeb Services, Inc. or its Affiliates. All rights reserved. Ask for exactly the data you need query { getUser(id: "123") { username tweets { body date } } } { "username": "...", "tweets": [ { "body": "...", "date": "..." }, { "body": "...", "date": "..." }, ] }
- 13. © 2018, AmazonWeb Services, Inc. or its Affiliates. All rights reserved. Subscriptions type Subscription { userTweeted(id: ID): Tweet @aws_subscribe(mutations: ["newTweet"]) } Subscription { userTweeted(id: "jdoe123") { body } }
- 14. © 2018, AmazonWeb Services, Inc. or its Affiliates. All rights reserved.
- 15. © 2018, AmazonWeb Services, Inc. or its Affiliates. All rights reserved. • DynamoDB • Elasticsearch • Lambda • HTTP • Everything else (via Lambda) Data Sources
- 16. © 2018, AmazonWeb Services, Inc. or its Affiliates. All rights reserved. Resolvers • Translate GraphQL requests to / from formats your data sources understand. • Request and response mapping templates. • Apache VTL (Velocity Template Language).
- 17. © 2018, AmazonWeb Services, Inc. or its Affiliates. All rights reserved. Request Mapping Template Response Mapping Template
- 18. © 2018, AmazonWeb Services, Inc. or its Affiliates. All rights reserved. { "version": "2017-02-28", "operation": "PutItem", "key": { "requestId": { "S": $util.autoId() } }, "attributeValues": { "timestamp": { "S": $util.time.nowISO8601() }, "requesterName": { "S": $context.args.name }, "requesterPhone": { "S": $context.args.phone } } } mutation { requestCall( name: String!, phone: String! ): Boolean } DynamoDB PutItem
- 19. © 2018, AmazonWeb Services, Inc. or its Affiliates. All rights reserved. #set($moistures = []) #foreach($reading in ${context.args.moisture}) $util.qr($moistures.add($util.dynamodb.toMapValues($reading))) #end #set($pHs = []) #foreach($reading in ${context.args.pH}) $util.qr($pHs.add($util.dynamodb.toMapValues($reading))) #end { "version": "2018-05-29", "operation": "BatchPutItem", "tables": { "moistureReadings": $util.toJson($moistures), "pHReadings": $util.toJson($pHs) } } input Moisture { timestamp: String value: Float } input pH { timestamp: String value: Float } mutation { record( moisture: [Moisture], pH: [pH] ) } DynamoDB Multi-Table Batch PutItem
- 20. © 2018, AmazonWeb Services, Inc. or its Affiliates. All rights reserved. Field Resolvers type Post { id: ID! text: String comments: [Comment] } type Comment { postId: ID! commentId: String! text: String } Posts id text Comments postId commentId text
- 21. © 2018, AmazonWeb Services, Inc. or its Affiliates. All rights reserved. Field Resolvers type Post { id: ID! text: String comments: [Comment] } type Comment { postId: ID! commentId: String! text: String } { "version": "2017-02-28", "operation": "Query", "query": { "expression": "postId = :postId", "expresssionValues": { ":postId": { "S": "$context.source.id" } } } }
- 22. © 2018, AmazonWeb Services, Inc. or its Affiliates. All rights reserved. More things you can do • Pagination & Scans (limit, nextToken) • Multi-table Batch Get / Update / Delete • Conditional Get / Put / Update / Delete (via Conditional Expressions)
- 23. © 2018, AmazonWeb Services, Inc. or its Affiliates. All rights reserved. • API Key • AWS IAM (access key + secret key / Cognito Federated Identities) • Cognito User Pools Security
- 24. © 2018, AmazonWeb Services, Inc. or its Affiliates. All rights reserved. context.identity { "sub": "...uuid...", "username": "...", "claims": { ...x }, "cognitoIdentityId": "...", "cognitoIdentityPoolId": "..." }
- 25. © 2018, AmazonWeb Services, Inc. or its Affiliates. All rights reserved. type Mutation { addPost(id: ID!, title: String!): Post! @aws_auth(cognito_groups: [“Bloggers", "Admins"]) } Using Cognito Groups
- 26. © 2018, AmazonWeb Services, Inc. or its Affiliates. All rights reserved. "condition": { "expression": “contains(#author, :username)", "expressionNames": { "#author": "Author" }, "expressionValues": { “:username": { "S": "${context.identity.username}" } } } Proceed only if author field matches username
- 27. © 2018, AmazonWeb Services, Inc. or its Affiliates. All rights reserved. • JavaScript (+ React, Angular, Vue.js) • React Native • iOS (Objective-C / Swift) • Android (Java / Kotlin) AppSync Client SDKs
- 28. © 2018, AmazonWeb Services, Inc. or its Affiliates. All rights reserved. .NET Clojure GoElixir PHP Scala RubyPython Standards Compliant GraphQL Clients Unity Perl Extras (offline support / optimistic updates) library dependent
- 29. © 2018, AmazonWeb Services, Inc. or its Affiliates. All rights reserved. AWS Amplify Apollo • Auth • Storage • Analytics • Notifications • Declarative data fetching • Normalized write-through cache • Optimistic UI • Deferred queries
- 30. © 2018, AmazonWeb Services, Inc. or its Affiliates. All rights reserved. Online UI Component
- 31. © 2018, AmazonWeb Services, Inc. or its Affiliates. All rights reserved. Offline UI Component
- 32. © 2018, AmazonWeb Services, Inc. or its Affiliates. All rights reserved. Back Online UI Component
- 33. © 2018, AmazonWeb Services, Inc. or its Affiliates. All rights reserved. React Example GET_POSTS = gql` { posts { title publishDate previewText } } `; <Query query={GET_POSTS}> {({ loading, data }) => { if (loading) return <LoadingSpinner />; return <PostsList data={data.posts} />; }} </Query>
- 34. © 2018, AmazonWeb Services, Inc. or its Affiliates. All rights reserved. Optimistic UI UI Component message { timestamp: "2018-09-30T23:43:05+05:30" text: "Hello", sent: False }
- 35. © 2018, AmazonWeb Services, Inc. or its Affiliates. All rights reserved. Optimistic UI UI Component message { timestamp: "2018-09-30T23:43:05+05:30" text: "Hello", sent: True }
- 36. © 2018, AmazonWeb Services, Inc. or its Affiliates. All rights reserved. Branch’s Architecture Other services Customer Apps Staff Staff AppSync Customer AppSync Customer Auth Staff Auth
- 37. © 2018, AmazonWeb Services, Inc. or its Affiliates. All rights reserved. What we love 😍 • Much much much less code! • No VMs, no containers to orchestrate, no uptime / reliability issues. • Tightly integrated dev/ops workflow. • Focus on what sets your business apart, instead of re-inventing the wheel.
- 38. © 2018, AmazonWeb Services, Inc. or its Affiliates. All rights reserved. What isn’t so great 😕 • No first-class RDS support (have to go through Lambda). • HTTP resolvers only work for public APIs — have to go through Lambda for endpoints inside VPCs. • Resolver mapping templates are hard to debug. • Need a Lambda function to index DynamoDB into Elasticsearch (super common). • Terraform support lagging behind. • Subscription updates are only triggered by mutations — not by external sources.
- 39. © 2018, AmazonWeb Services, Inc. or its Affiliates. All rights reserved. Adithya Reddy @TheTallpants github.com/tallpants TheTallpants@gmail.com