@setho/dynamodb-repository
v0.9.0
Published
DynamoDB repository for hash-key and hash-key/range indexed tables. Designed for Lambda use. Handles nice-to-haves like created and updated timestamps and default id creation.
Downloads
48
Maintainers
Readme
dynamodb-repository
DynamoDB repository for key-value indexed tables. Designed for Lambda use. Handles niceties like created and updated timestamps and default id creation.
Install
$ npm install @setho/dynamodb-repository --save
Usage
TypeScript/ES6
import { KeyValueRepository } from '@setho/dynamodb-repository';
const myRepo = new KeyValueRepository({
tableName: 'Items', // Required
keyName: 'id', // Required
idOptions: {
// Optional
prefix: 'ITEM_', // Default is empty string
},
documentClient, // Required - V3 DynamoDBDocumentClient from @aws-sdk/lib-dynamodb
});
JavaScript
const { KeyValueRepository } = require('@setho/dynamodb-repository');
const myRepo = new KeyValueRepository({
tableName: 'Items', // Required
keyName: 'id', // Required
idOptions: {
// Optional
prefix: 'ITEM#', // Default is empty string
},
documentClient, // Required - V3 DynamoDBDocumentClient from @aws-sdk/lib-dynamodb
});
Constructor
Use the optional idOptions
constructor parameter to set an optional prefix
to give your ids some human-readable context. The remainder of the key is a ULID, which is both unique and lexicographically sortable. See an explanation of and motivation for ULIDs here.
Create
- Requires action
dynamodb:PutItem
- Automatically adds a string key (this will overwrite any you may try to provide). Use constructor options to specify length and optional prefix.
- Automatically provides a
createdAt
andupdatedAt
timestamp in ISO-8601 - Returns what was saved; does not mutate the item passed in.
const mySavedItem = await myRepo.create(myItem);
mySavedItem.id; // itm_a4d02890b7174730b4bbbc
mySavedItem.createdAt; // 1979-11-04T09:00:00.000Z
mySavedItem.updatedAt; // 1979-11-04T09:00:00.000Z
Get by Key
- Requires action
dynamodb:GetItem
. - Throws
404
if item not found using http-errors.
const myItem = await myRepo.get(id);
Get Many
- Requires action
dynamodb:Scan
- Accepts optional parameter fields
limit
andcursor
limit
defaults to 100
- Returns object with
items
(Array) andcursor
(String)items
will always be an array; if nothing found, it will be emptycursor
will be present if there are more items to fetch, otherwise it will be undefined
// Example to pull 100 at time until you have all items
const allItems = [];
const getAllItems = async ({ limit, cursor = null }) => {
const getResult = await myRepo.getMany({ limit, cursor });
allItems.push(...getResult.items);
if (getResult.cursor) {
await getAllItems({ cursor: getResult.cursor });
}
};
await getAllItems();
// The array allItems now has all your items. Go nuts.
Remove by Key
- Requires action
dynamodb:DeleteItem
await myRepo.remove(id);
Update
- Requires
dynamodb:UpdateItem
- Honors revision check; it will only update if the revision on disk is the one you are updating. Will return a
409
if the revision has changed underneath you. - Will perform a partial update if you don't pass in all properties. Think of this as a "patch" vs. a replacement update. The
key
andrevision
properties are always required. - Returns the entire entity, including both new and unchanged properties
const person = await myRepo.create({
name: 'Joe',
age: 28,
favoriteColor: 'blue',
});
// Full item update
person.favoriteColor = 'teal';
const newPerson1 = await myRepo.update(person);
console.log(newPerson1.favoriteColor); // 'teal'
// Partial update
const partial = {
favoriteColor: 'aquamarine',
key: person.key,
revision: newPerson1.revision,
};
const newPerson2 = await myRepo.update(partial);
console.log(newPerson2.favoriteColor); // 'aquamarine'
console.log(newPerson2.age); // 28
// More Coming Soon...