DynamoDB ODM API Example

other-file.ts

import { Survey, OpenState, ClosedState, DeletedState } from "somewhere/Survey.ts";

// make a new one
let survey = new Survey();
// save it
await survey.save();
// Get from DB
survey = await Survey.get(survey.id);
// Transition the state to another state
await survey.transitionTo(OpenState);
// Get fro DB
let openSurvey = await Survey.get(survey.id);
// Transition teh state to another state
await openSurvey.transitionTo(ClosedState);
// Get all from DB
let surveys = await Survey.batchGet();
// Transition all of them
await Promise.all(surveys.map((survey: Survey) => {
  return survey.transitionTo(DeletedState);
}));

Survey.ts

// Survey.ts
import { Table, HashKey, RangeKey, Attribute, GlobalSecondaryIndex } from "@foobar/core";
import { Stateful, StateAttribute, State, DefaultState } from "@foobar/stateful";

export class CreatedState extends State {}
export class OpenState extends State {}
export class ClosedState extends State {}
export class DisabledState extends State {}
export class DeletedState extends State {}

@Stateful()
export class Survey extends Table {
  @HashKey({ uuid: true })
  id: string;

  @Attribute()
  allMembers: boolean;

  @Attribute()
  allowIgnore: boolean;

  @Attribute()
  buttonText: string;

  @Attribute()
  completeText: string;

  @GlobalSecondaryIndex({ name: "orgIndex", project: true, throughput: 1})
  org: string;

  @Attribute()
  members: string[];

  @GlobalSecondaryIndex({ name: "sendTimeIndex", rangeKey: "sendTime", project: true, throughput: 1 })
  sendDate: string;

  @Attribute()
  sendTime: number;
  
  @StateAttribute()
  state: string;

  protected states() {
    return {
      DefaultState: [ CreatedState, DeletedState ],
      CreatedState: [ OpenState, DeletedState, DisabledState ],
      OpenState: [ ClosedState ],
      ClosedState: [ OpenState, DisabledState, DeletedState ],
      DisabledState: [ OpenState, DeletedState ],
      DeletedState: [ CreatedState ]
    };
  }
  // Called before any transition...has default implementation
  protected async beforeTransition(previous: State, next: State) {
    switch (next)  {
      case DeletedState: {
        this.members = [];
      }
    }
    await this.save();
  }
}