👾DynamoDB

soketi supports connecting to a DynamoDB table (global or regional) to retrieve app data. This driver is highly efficient for this purpose since no strong consistency is needed and there are two indexes that will be used (AppId and AppKey).

Of course, soketi requires your DynamoDB table to use a predefined schema so that soketi knows how to retrieve your app data. The following DynamoDB schema is written in Javascript, but may be translated to other formats as needed:

ddb.createTable({
    // ...

    AttributeDefinitions: [
        {
            AttributeName: 'AppId',
            AttributeType: 'S',
        },
        {
            AttributeName: 'AppKey',
            AttributeType: 'S',
        },
    ],

    KeySchema: [{
        AttributeName: 'AppId',
        KeyType: 'HASH',
    }],

    GlobalSecondaryIndexes: [{
        IndexName: 'AppKeyIndex',
        KeySchema: [{
            AttributeName: 'AppKey',
            KeyType: 'HASH',
        }],
        Projection: {
            ProjectionType: 'ALL',
        },
        ProvisionedThroughput: {
            // ...
        },
    }],

    // ...
});

Inserting data into this table would look like the following:

const params = {
    TableName: 'apps',
    Item: {
        AppId: { S: 'app-id' },
        AppKey: { S: 'app-key' },
        AppSecret: { S: 'app-secret' },
        MaxConnections: { N: '-1' },
        EnableClientMessages: { B: 'false' },
        Enabled: { B: 'true' },
        MaxBackendEventsPerSecond: { N: '-1' },
        MaxClientEventsPerSecond: { N: '-1' },
        MaxReadRequestsPerSecond: { N: '-1' },
        Webhooks: { S: '[]' },
        EnableUserAuthentication: { B: 'false' },
    },
};

ddb.putItem(params);

Note that the "Webhooks" field is stored as a JSON-encoded string.

AWS has detailed documentation with many ways to define credentials for the DynamoDB client. soketi uses the same conventions, so you are free to define your AWS credentials in the .aws folder, environment variables, or from an EC2 / ECS profile.

IAM Permissions

The IAM Policy needed to work with the DynamoDB driver must contain the following permissions:

• dynamodb:GetItem (for AppId retrieval)

• dynamodb:Query (for AppKey retrieval)

Environment Variables

The following environment variables are used to control the behavior of the DynamoDB app driver:

Name	Default	Possible values	Description
SOKETI_APP_MANAGER_DYNAMODB_TABLE	apps	Any string	The table to pull the app data from.
SOKETI_APP_MANAGER_DYNAMODB_REGION	us-east-1	Any AWS region	The DynamoDB region the table was deployed to. For global tables, you may choose any region.
SOKETI_APP_MANAGER_DYNAMODB_ENDPOINT	''	Any URL	The endpoint used to connect to DynamoDB. May be used for testing or for local DynamoDB configurations.

Limits on an app-by-app basis

Your items in DynamoDB can have the following fields:

MaxPresenceMembersPerChannel: { N: '-1' },
MaxPresenceMemberSizeInKb: { N: '-1' },
MaxChannelNameLength: { N: '-1' },
MaxEventChannelsAtOnce: { N: '-1' },
MaxEventNameLength: { N: '-1' },
MaxEventPayloadInKb: { N: '-1' },
MaxEventBatchSize: { N: '-1' },

Not setting any of the above fields will ignore the setting, and will fallback to the limits associated with the server-level declared defaults.