🔒 DDB-Table

Strongly typed library for querying and modeling DynamoDB documents in TypeScript.

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DDB-Table was built to provide strongly-typed data structures over DynamoDB tables. Using **AWS
DocumentClient & TypeScript** you can easily fetch and store any JSON document and validate it’s
structure statically. Query secondary indexes and run complicated update expressions without any
error on runtime.

``ts
await table
.update('demo@example.com')
.set('FullName', 'John Doe')
// 🚨 TypeScript Error: 'fullName' is not assignable to 'Email' | 'FullName'
.condition((cond) => cond.eq('fullName', 'Johnny Doe'))
.exec();
`

$3

- Strongly Typed - End-to-end TypeScript validation for your data.
- Easy Query Expressions - Automatically escape name attributes and values.
- Smart Projections - Make sure you only access the fields you project.
- Query & Scan Indexes - Complete support for global or local indexes.
- Pure JavaScript - Also works without TypeScript.

$3

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this project.

Install

`bash
npm i ddb-table
`

Usage

`ts
import Table from 'ddb-table';
import { DynamoDBClient } from '@aws-sdk/client-dynamodb';
import { DynamoDBDocument } from '@aws-sdk/lib-dynamodb';


interface MessageSchema {
threadId: string;
timestamp: number;
senderId: string;
message: string;
status: 'sent' | 'received';
tags?: Set;
attachments: {
name: string;
URL: string;
}[];
}

const client = new DynamoDBClient({
// settings...
});

// create the basic table definition
const messages = new Table({
tableName: 'Messages',
primaryKey: 'threadId',
sortKey: 'timestamp',
documentClient: DynamoDBDocument.from(client);
});

const updateRes = await messages
.update('john@gmail.com', 1588191225322)
.set('message', 'Hello World!')
.add('tags', new Set(['unread', 'important']))
.set('attachments', (exp) =>
exp.listAppend([{ name: 'Test', URL: 'demo.com' }]),
)
.return('ALL_NEW')
.exec();

console.log(updateRes.Attributes);
`

#### Working with indexes as well:

`ts
// create a secondary index definition
type SenderTimestampIndex = Pick<
MessageSchema,
'threadId' | 'timestamp' | 'senderId'
>;

const outboxIndex = messages.index<
SenderTimestampIndex,
'senderId',
'timestamp'
>('senderId-timestamp-index', 'senderId', 'timestamp');

const it = outboxIndex
.query()
.keyCondition((cond) => cond.eq('senderId', 'john@gmail.com'))
.keyCondition((cond) =>
cond.between('timestamp', Date.now() - 3600e3, Date.now()),
)
.project({ threadId: 1, message: 1 })
.reverseIndex()
.entries();

for await (const item of it) {
console.log(item);
}
`

$3

`ts
import { DynamoDBExceptionName } from 'ddb-table';

try {
await table.put(...).exec();
} catch (err) {
if ((err as DynamoDBServiceException)?.name === DynamoDBExceptionName.ConditionalCheckFailedException) {
// handle exception
}
}
``

License

MIT license © 2022 Neuledge