repository-aws-dynamodb

BaseModel

This library provides a BaseModel class that can be extended in order to model, and then easily query for and modify data in your AWS DynamoDB tables.

You'll need to define each of your table models like so:

export interface Invitation extends BaseObject {
  id: string;
  email: string;
  code: string;
  expires?: number;
  createdBy?: string;
  updatedBy?: string;
}

class InvitationModel extends BaseModel<Invitation> {
  constructor() {
    super({
      tableName: 'invitation',
      keys: {
        hashKey: 'id',
        rangeKey: 'dateCreated',
        globalIndexes: {
          'code-index': {
            hashKey: 'code'
          }
        }
      }
    });
  }
}

Subsequently, you can create a singleton instance of your class, in order to call one of the several class functions available.

When calling super in your class constructor, you can also override some default options:

• config.dateUnits: ms for millisecond timestamps, s for second timestamps (default s).
• stage: ('postfix' | 'prefix' | 'none'), whether the current env.SERVERLESS_STAGE should be prepended or appended to the tableName.

It's recommended to also create a function on your class that would be responsible for creating a new instance of an object to be persisted, in order to ensure default field values are set consistently.

Getter and query functions expect an object containing the hashKey (and rangeKey if applicable) defined in the model.

the queryIndex function expects an object containing the keys defined in the relevant globalIndex.

By default, query functions will paginate up to 7 requests to DynamoDB before logging a warning and returning a truncated result set.

Write operations will automatically set/update createdBy, updatedBy, dateUpdated and dateCreated properties on the saved object where possible/appropriate.

CFTableBuilder

The CFTableBuilder provides a builder class to allow easy creation of DynamoDB table definitions for CloudFormation templates.

e.g.

{
  TableInvitation: new CFTableBuilder('${self:provider.stage}-invitation')
    .attribute({ name: 'id', type: 'S', key: 'HASH' })
    .attribute({ name: 'dateCreated', type: 'N', key: 'RANGE' })
    .attribute({ name: 'code', type: 'S' })
    .ttl('expires')
    .globalSecondaryIndex('code-index')
    .key({ name: 'code', key: 'HASH' })
    .build();
}