section 3 setup and initial trigger migrations

Author: dkkloimwieder

client/src/index.js

@@ -2,12 +2,41 @@ import React from 'react';
 import ReactDOM from 'react-dom';
 import './index.css';
 import App from './App';
-import { ApolloClient, InMemoryCache, ApolloProvider } from '@apollo/client';
+import {
+  ApolloClient,
+  InMemoryCache,
+  ApolloProvider,
+  split,
+  HttpLink,
+} from '@apollo/client';
+import { getMainDefinition } from '@apollo/client/utilities';
+import { WebSocketLink } from '@apollo/client/link/ws';
 
-console.log(process.env);
+const httpLink = new HttpLink({
+  uri: 'http://localhost:4000/graphql',
+});
+
+const wsLink = new WebSocketLink({
+  uri: 'ws://localhost:4000/graphql',
+  options: {
+    reconnect: true,
+  },
+});
+
+const splitLink = split(
+  ({ query }) => {
+    const definition = getMainDefinition(query);
+    return (
+      definition.kind === 'OperationDefinition' &&
+      definition.operation === 'subscription'
+    );
+  },
+  wsLink,
+  httpLink
+);
 
 const client = new ApolloClient({
-  uri: 'http://127.0.0.1:3333/graphql' /* variables from toplevel project .env */,
+  link: splitLink,
   cache: new InMemoryCache({
     typePolicies: {
       Query: {
@@ -20,7 +49,7 @@ const client = new ApolloClient({
         },
       },
     },
-  }) /*NOTHING TO SEEEE!!{ dataIdFromObject: (object) => object.nodeId }*/,
+  }),
 });
 
 ReactDOM.render(

migrations/20211014012149-trigger-function-todo.js

@@ -0,0 +1,53 @@
+'use strict';
+
+var dbm;
+var type;
+var seed;
+var fs = require('fs');
+var path = require('path');
+var Promise;
+
+/**
+  * We receive the dbmigrate dependency from dbmigrate initially.
+  * This enables us to not have to rely on NODE_PATH.
+  */
+exports.setup = function(options, seedLink) {
+  dbm = options.dbmigrate;
+  type = dbm.dataType;
+  seed = seedLink;
+  Promise = options.Promise;
+};
+
+exports.up = function(db) {
+  var filePath = path.join(__dirname, 'sqls', '20211014012149-trigger-function-todo-up.sql');
+  return new Promise( function( resolve, reject ) {
+    fs.readFile(filePath, {encoding: 'utf-8'}, function(err,data){
+      if (err) return reject(err);
+      console.log('received data: ' + data);
+
+      resolve(data);
+    });
+  })
+  .then(function(data) {
+    return db.runSql(data);
+  });
+};
+
+exports.down = function(db) {
+  var filePath = path.join(__dirname, 'sqls', '20211014012149-trigger-function-todo-down.sql');
+  return new Promise( function( resolve, reject ) {
+    fs.readFile(filePath, {encoding: 'utf-8'}, function(err,data){
+      if (err) return reject(err);
+      console.log('received data: ' + data);
+
+      resolve(data);
+    });
+  })
+  .then(function(data) {
+    return db.runSql(data);
+  });
+};
+
+exports._meta = {
+  "version": 1
+};

migrations/sqls/20211014012149-trigger-function-todo-down.sql

@@ -0,0 +1,2 @@
+DROP TRIGGER IF EXISTS trigger_todo ON todo_public.todo;
+DROP FUNCTION IF EXISTS notify_todo();

migrations/sqls/20211014012149-trigger-function-todo-up.sql

@@ -0,0 +1,15 @@
+CREATE OR REPLACE FUNCTION notify_todo()
+   RETURNS trigger AS $$
+   BEGIN
+     PERFORM pg_notify(
+         'postgraphile:todo',
+         json_build_object('__node__', json_build_array('todos', NEW.id))::text);
+     RETURN NEW;
+   END;
+   $$ LANGUAGE plpgsql;
+
+CREATE TRIGGER trigger_todo
+    AFTER INSERT
+    ON todo_public.todo
+    FOR EACH ROW
+    EXECUTE PROCEDURE notify_todo();

package.json

@@ -8,6 +8,7 @@
   "license": "MIT",
   "dependencies": {
     "@graphile-contrib/pg-simplify-inflector": "^6.1.0",
+    "@graphile/pg-pubsub": "^4.12.1",
     "cors": "^2.8.5",
     "db-migrate": "^1.0.0-beta.16",
     "db-migrate-pg": "^1.2.2",

server/postgraphile.js

@@ -1,5 +1,8 @@
-const { postgraphile } = require('postgraphile');
+const { postgraphile, makePluginHook } = require('postgraphile');
 const PgSimplifyInflectorPlugin = require('@graphile-contrib/pg-simplify-inflector');
+const { default: PgPubsub } = require('@graphile/pg-pubsub');
+
+const pluginHook = makePluginHook([PgPubsub]);
 
 const {
   POSTGRES_DB,
@@ -26,5 +29,8 @@ module.exports = postgraphile(
     simpleCollections: 'only',
     graphileBuildOptions: { pgOmitListSuffix: true },
     classicIds: true,
+    pluginHook,
+    subscriptions: true,
+    simpleSubscriptions: true,
   }
 );

yarn.lock

@@ -14,6 +14,17 @@
   dependencies:
     tslib "^2.0.1"
 
+"@graphile/pg-pubsub@^4.12.1":
+  version "4.12.1"
+  resolved "https://registry.yarnpkg.com/@graphile/pg-pubsub/-/pg-pubsub-4.12.1.tgz#c47e1bafde6227f53304ea9ce70558c76fd0578a"
+  integrity sha512-0HR7HN/CZcwkw+pLrmcxGcEkk7U9TvB+rhknjoN8M7agMeYNP/yMgJ2L+4Rgcsnu8a+vszx+AYNFdkGtKE/edw==
+  dependencies:
+    "@types/debug" "^4.1.4"
+    "@types/pg" ">=6 <9"
+    debug "^4.1.1"
+    graphql-subscriptions "^1.1.0"
+    tslib "^2.0.1"
+
 "@sindresorhus/is@^0.14.0":
   version "0.14.0"
   resolved "https://registry.yarnpkg.com/@sindresorhus/is/-/is-0.14.0.tgz#9fb3a3cf3132328151f353de4632e01e52102bea"
@@ -26,6 +37,13 @@
   dependencies:
     defer-to-connect "^1.0.1"
 
+"@types/debug@^4.1.4":
+  version "4.1.7"
+  resolved "https://registry.yarnpkg.com/@types/debug/-/debug-4.1.7.tgz#7cc0ea761509124709b8b2d1090d8f6c17aadb82"
+  integrity sha512-9AonUzyTjXXhEOa0DnqpzZi6VHlqKMswga9EXjpXnnqxwLtdvPPtlO8evrI5D9S6asFRCQ6v+wpiUKbw+vKqyg==
+  dependencies:
+    "@types/ms" "*"
+
 "@types/json5@^0.0.30":
   version "0.0.30"
   resolved "https://registry.yarnpkg.com/@types/json5/-/json5-0.0.30.tgz#44cb52f32a809734ca562e685c6473b5754a7818"
@@ -38,6 +56,11 @@
   dependencies:
     "@types/node" "*"
 
+"@types/ms@*":
+  version "0.7.31"
+  resolved "https://registry.yarnpkg.com/@types/ms/-/ms-0.7.31.tgz#31b7ca6407128a3d2bbc27fe2d21b345397f6197"
+  integrity sha512-iiUgKzV9AuaEkZqkOLDIvlQiL6ltuZd9tGcW3gwpnX8JbuiuhFlEGmmFXEXkN50Cvq7Os88IY2v0dkDqXYWVgA==
+
 "@types/node@*":
   version "16.10.3"
   resolved "https://registry.yarnpkg.com/@types/node/-/node-16.10.3.tgz#7a8f2838603ea314d1d22bb3171d899e15c57bd5"
@@ -737,6 +760,13 @@ [email protected]:
     debug "^4.1.1"
     tslib "^2.0.1"
 
+graphql-subscriptions@^1.1.0:
+  version "1.2.1"
+  resolved "https://registry.yarnpkg.com/graphql-subscriptions/-/graphql-subscriptions-1.2.1.tgz#2142b2d729661ddf967b7388f7cf1dd4cf2e061d"
+  integrity sha512-95yD/tKi24q8xYa7Q9rhQN16AYj5wPbrb8tmHGM3WRc9EBmWrG/0kkMl+tQG8wcEuE9ibR4zyOM31p5Sdr2v4g==
+  dependencies:
+    iterall "^1.3.0"
+
 graphql-ws@^5.1.2:
   version "5.5.0"
   resolved "https://registry.yarnpkg.com/graphql-ws/-/graphql-ws-5.5.0.tgz#79f10248d23d104369eaef93acb9f887276a2c42"
@@ -935,7 +965,7 @@ is-yarn-global@^0.3.0:
   resolved "https://registry.yarnpkg.com/is-yarn-global/-/is-yarn-global-0.3.0.tgz#d502d3382590ea3004893746754c89139973e232"
   integrity sha512-VjSeb/lHmkoyd8ryPVIKvOCn4D1koMqY+vqyjjUfc3xyKtP4dYOxM44sZrnqQSzSds3xyOrUTLTC9LVCVgLngw==
 
-iterall@^1.0.2, iterall@^1.2.1, iterall@^1.2.2:
+iterall@^1.0.2, iterall@^1.2.1, iterall@^1.2.2, iterall@^1.3.0:
   version "1.3.0"
   resolved "https://registry.yarnpkg.com/iterall/-/iterall-1.3.0.tgz#afcb08492e2915cbd8a0884eb93a8c94d0d72fea"
   integrity sha512-QZ9qOMdF+QLHxy1QIpUHUU1D5pS2CG2P69LF6L6CPjPYA/XMOmKV3PZpawHoAjHNyB0swdVTRxdYT4tbBbxqwg==