shaykav

if (eventType === 'MESSAGE') {
  const message = JSON.parse(event.body);

  // Handshake with Apollo
  if (message.type === 'connection_init') {
    // Write connection to persistence
    const connection = Object.assign(new Connection(), {
      id: connectionId,
      requestContext: event.requestContext,
      payload: event.body.payload

shaykav

import { DataMapper } from '@aws/dynamodb-data-mapper';
import { DynamoDB } from 'aws-sdk';

export const mapper = new DataMapper({
  client: new DynamoDB({ region: 'us-east-1' })
});

shaykav

// GET for connection item 
mapper.get(Object.assign(new Connection(), {
  id: connectionId
}));

shaykav

const gateway = createGateway(event.requestContext);

// Server sending message to client acknowledging connection_init
gateway.postToConnection({
  ConnectionId: event.requestContext.connectionId,
  Data: JSON.stringify({ type: 'connection_ack', payload: {} })
});

shaykav

import { attribute, hashKey, rangeKey } from '@aws/dynamodb-data-mapper-annotations';
import { APIGatewayEventRequestContext } from 'aws-lambda';

@table('SUBSCRIPTION_TABLE')
export class Subscription {
  /*
   * Combination of connectionId and subscriptionId
   * `${connectionId}|${subscriptionId}`
   */
  @hashKey({ type: 'String' })

shaykav

import { attribute, hashKey, table } from '@aws/dynamodb-data-mapper-annotations';
import { APIGatewayEventRequestContext } from 'aws-lambda';

@table('CONNECTION_TABLE')
export class Connection {
  /* ConnectionId */
  @hashKey()
  id: string;

  @attribute({defaultProvider: () => new Date()})

shaykav

functions:
  websocket:
    name: example-websocket
    handler: ws-handler.handler
    events:
      - websocket:
          route: $connect
      - websocket:
          route: $disconnect
      - websocket:

shaykav

resources:
  Resources:
    connectionsTable:
      Type: AWS::DynamoDB::Table
      Properties:
        TableName: CONNECTION_TABLE
        AttributeDefinitions:
          - AttributeName: id
            AttributeType: S
        KeySchema:

shaykav

import { ApiGatewayManagementApi } from 'aws-sdk';

export const createGateway = (requestContext: any) =>
  new ApiGatewayManagementApi({
    apiVersion: 'latest',
    endpoint: `https://${requestContext.apiId}
      .execute-api.us-east-1.amazonaws.com/${requestContext.stage}`
  });

shaykav

import React, { FC } from 'react';
import { ApolloProvider } from '@apollo/react-hooks';
import {
  InMemoryCache,
  ApolloClient,
  HttpLink,
  split,
} from 'apollo-boost';

// WS link from example here - https://github.com/enisdenjo/graphql-ws#apollo-client