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    0.1.7 • Public • Published

    DynamoDB database adapter for Yjs

    Rewritten from y-leveldb to use AWS DynamoDB.


    docker-compose -f docker-compose-dynamodb-local.yml up
    node ./testrun
    aws dynamodb list-tables --endpoint-url http://localhost:8000 --region us-west-2
    aws dynamodb scan --table-name test-y-dynamodb --endpoint-url http://localhost:8000 --region us-west-2

    Use it

    npm install y-dynamodb --save
    const DynamoDbPersistence = require('./src/y-dynamodb')
    const Y = require('yjs')
    const config = {
      aws: {
        region: 'us-west-2',
        accessKeyId: 'accessKeyId',
        secretAccessKey: 'secretAccessKey',
        endpoint: 'http://localhost:8000'
      skipCreateTable: true, // skips creating table, assumes it already exists
      tableName: 'test-y-dynamodb'
    const persistence = DynamoDbPersistence(config)
    const ydoc = new Y.Doc()
    ydoc.getArray('arr').insert(0, [1, 2, 3])
    console.log(ydoc.getArray('arr').toArray()) // => [1, 2, 3]
    // store document updates retrieved from other clients
    persistence.storeUpdate('my-doc', Y.encodeStateAsUpdate(ydoc))
    // when you want to sync, or store data to a database,
    // retrieve the temporary Y.Doc to consume data
      .then(doc => console.log('Got my-doc', doc.getArray('arr').toArray())) // [1, 2, 3]


    persistence = DynamoDbPersistence(config)

    Create a y-dynamodb persistence instance.

    persistence.getYDoc(docName: string): Promise<Y.Doc>

    Create a Y.Doc instance with the data persisted in DynamoDB. Use this to temporarily create a Yjs document to sync changes or extract data.

    persistence.storeUpdate(docName: string, update: Uint8Array): Promise

    Store a single document update to the database.

    persistence.getStateVector(docName: string): Promise<Uint8Array>

    The state vector (describing the state of the persisted document - see Yjs docs) is maintained in a separate field and constantly updated.

    This allows you to sync changes without actually creating a Yjs document.

    persistence.getDiff(docName: string, stateVector: Uint8Array): Promise<Uint8Array>

    Get the differences directly from the database. The same as Y.encodeStateAsUpdate(ydoc, stateVector).

    persistence.clearDocument(docName: string): Promise

    Delete a document, and all associated data from the database.

    persistence.setMeta(docName: string, metaKey: string, value: any): Promise

    Persist some meta information in the database and associate it with a document. It is up to you what you store here. You could, for example, store credentials here.

    persistence.getMeta(docName: string, metaKey: string): Promise<any|undefined>

    Retrieve a store meta value from the database. Returns undefined if the metaKey doesn't exist.

    persistence.getMetas(docName: string): Promise<Map<string, any>>

    Retries all meta keys and values from the database for a document.

    persistence.delMeta(docName: string, metaKey: string): Promise

    Delete a store meta value.

    persistence.flushDocument(docName: string): Promise (dev only)

    Internally y-dynamodb stores incremental updates. You can merge all document updates to a single entry. You probably never have to use this.


    Here's an example stack if you're using AWS CDK:

    class AwsCdkStack extends cdk.Stack {
      constructor (scope, id, props) {
        super(scope, id, props)
        const docsTable = new dynamodb.Table(this, 'test-y-dynamodb', {
          partitionKey: { name: 'ydocname', type: dynamodb.AttributeType.STRING },
          sortKey: { name: 'ykeysort', type: dynamodb.AttributeType.BINARY },
          tableName: 'test-y-dynamodb'
        const user = new iam.User(this, 'YDatabaseUser', { userName: 'YDatabaseUser' })
        const accessKey = new iam.CfnAccessKey(this, 'myAccessKey', { userName: user.userName })
        new cdk.CfnOutput(this, 'accessKeyId', { value: accessKey.ref })
        new cdk.CfnOutput(this, 'secretAccessKey', { value: accessKey.attrSecretAccessKey })


    y-dynamodb is licensed under the MIT License.




    npm i y-dynamodb

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