Merge pull request #112 from leapfrogtechnology/node-app-pg-ts

Make running the example a trivial process

examples/node-app-pg-ts/Dockerfile

@@ -1,5 +1,5 @@
-From node:10
+From node:14-slim
 WORKDIR /app/
 COPY . .
 RUN yarn
-CMD yarn sync-db && yarn start
+CMD yarn sync-db synchronize && yarn start

examples/node-app-pg-ts/README.md

@@ -0,0 +1,64 @@
+# Node PostgreSQL Example with TypeScript Migrations
+
+Sample project for sync-db using PostgreSQL and migrations written in TypeScript.
+
+## Overview
+
+This `sync-db` example does a few things in order:
+
+- Prunes database objects inside of [src/sql](src/sql) from the specified database connection(s) if it exists.
+- Executes knex database migrations inside of [src/migrations](src/migrations) directory written in TypeScript.
+- Creates database objects inside of [src/sql](src/sql) directory using `sync-db`. These database objects are created in the order specified in [sync-db.yml](sync-db.yml).
+- Executes a [node script](src/index.js) to check if the synchronized objects can be executed and prints the result.
+
+## Setup
+
+Setup will require [docker](https://docs.docker.com/engine/) and [docker-compose](https://docs.docker.com/compose/gettingstarted/).
+
+Configure database connection(s) in `connections.sync-db.json` by copying `connections.sync-db.json.example`. For ease of use, the example app will work without making any changes to `connections.sync-db.json`. Throwaway database credentials have been set in [docker-compose.yml](docker-compose.yml).
+
+```bash
+$ cp connections.sync-db.json.example connections.sync-db.json
+```
+
+## Run
+
+Run the docker-compose services in order.
+
+```bash
+$ docker-compose up -d db
+$ docker-compose up app
+```
+
+## Output
+
+```bash
+example-app | yarn run v1.22.5
+example-app | $ /app/node_modules/.bin/sync-db synchronize
+example-app | Synchronizing...
+example-app |
+example-app |  ▸ db1
+example-app |    [✓] Synchronization - started
+example-app |    [✓] Synchronization - pruned (0s)
+example-app |    [✓] Migrations - up to date (0.02s)
+example-app |    [✓] Synchronization - completed (0.13s)
+example-app |
+example-app | Synchronization complete for 1 / 1 connection(s). (0.25s)
+example-app |
+example-app | Done in 0.54s.
+example-app | yarn run v1.22.5
+example-app | $ node src/index.js
+example-app |
+example-app | List of table names in the database:
+example-app |  [ 'knex_migrations', 'knex_migrations_lock', 'users', 'todos' ]
+example-app |
+example-app | List of user names in the database:
+example-app |  [ 'sync' ]
+example-app |
+example-app | Calculations:
+example-app |  { 'Sum of 6 and 7': 13, 'Square of 6': 36, 'Product of 6 and 7': 42 }
+example-app |
+example-app | Current date time: 2021-03-21T00:00:00.000Z
+example-app | Done in 0.11s.
+example-app exited with code 0
+```

examples/node-app-pg-ts/connections.sync-db.json.example

@@ -1,12 +1,12 @@
 {
   "connections": [
     {
-      "id": "laudio_test_db",
-      "client": "postgresql",
+      "id": "db1",
+      "client": "pg",
       "connection": {
-        "host": "localhost",
+        "host": "db",
         "port": 5432,
-        "user": "testdb",
+        "user": "test",
         "database": "testdb",
         "password": "secret"
       }

examples/node-app-pg-ts/docker-compose.yml

@@ -1,13 +1,14 @@
 version: '3.3'
 services:
   db:
-    image: 'postgres'
+    image: 'postgres:13-alpine'
     container_name: 'example-pg'
     ports:
       - '5432:5432'
     environment:
-      DATABASE_URL: ${DATABASE_URL}
-      POSTGRES_DB: 'mydatabasename'
+      POSTGRES_DB: 'testdb'
+      POSTGRES_USER: 'test'
+      POSTGRES_PASSWORD: 'secret'
   app:
     container_name: 'example-app'
     build: .

examples/node-app-pg-ts/knexfile.js

@@ -1,8 +1,7 @@
-require('@babel/register');
 const { connections } = require('./connections.sync-db.json');
 
 module.exports = {
-  client: 'postgresql',
+  client: 'pg',
   connection: connections[0],
   migrations: {
     directory: './src/migrations',

examples/node-app-pg-ts/package.json

@@ -9,22 +9,18 @@
     "migrate:list": "../../bin/run-dev.sh migrate-list",
     "migrate": "../../bin/run-dev.sh migrate-latest",
     "rollback": "../../bin/run-dev.sh migrate-rollback",
-    "start": " babel-node src/index.js",
+    "start": "node src/index.js",
     "make": "knex --knexfile=knexfile.js migrate:make"
   },
   "license": "MIT",
   "dependencies": {
-    "@leapfrogtechnology/sync-db": "1.0.0-beta.8",
-    "knex": "^0.20.3",
-    "pg": "^7.14.0",
+    "@leapfrogtechnology/sync-db": "1.0.0-beta.10",
+    "knex": "^0.95.2",
+    "pg": "^8.5.1",
     "ts-node": "^9.1.1",
     "typescript": "^4.2.3"
   },
   "devDependencies": {
-    "@babel/core": "^7.7.4",
-    "@babel/node": "^7.7.4",
-    "@babel/preset-env": "^7.7.4",
-    "@babel/register": "^7.7.4",
     "eslint": "^6.7.2",
     "eslint-config-leapfrog": "^2.0.1"
   }

examples/node-app-pg-ts/src/index.js

@@ -1,22 +1,33 @@
 /**
  * Demonstrates use of sync-db to create functions, procedures and views in PostgresSql.
  */
-const knex = require('knex');
-const { connections } = require('../connections.sync-db.json');
+const dbConfig = require('../knexfile').connection.connection;
 
 (async () => {
   try {
-    const db = knex({
-      client: 'postgresql',
-      connection: connections.find(({ id }) => id === 'db1')
+    // PostgreSQL connection only works with a connection string.
+    // Time wasted = 60 minutes
+    const db = require('knex')({
+      client: 'pg',
+      connection: `postgresql://${dbConfig.user}:${dbConfig.password}@${dbConfig.host}:${dbConfig.port}/${dbConfig.database}`
     });
 
-    const tables = await db.raw('SELECT * FROM utils.vw_table_names');
-    const users = await db.raw('SELECT * FROM utils.vw_user_names');
-    const [{ result: product }] = await db.raw('SELECT utils.product(6, 7) AS result;');
-    const [{ result: sum }] = await db.raw('SELECT dbo.sum(6, 7) AS result;');
-    const [{ result: square }] = await db.raw('SELECT dbo.square(6) AS result;');
-    const [{ result: date }] = await db.raw('EXEC utils.get_date;');
+    const { rows: tables } = await db.raw('SELECT * FROM utils.vw_table_names');
+    const { rows: users } = await db.raw('SELECT * FROM utils.vw_user_names');
+
+    const {
+      rows: [{ result: sum }]
+    } = await db.raw('SELECT public.sum(6, 7) AS result;');
+    const {
+      rows: [{ result: square }]
+    } = await db.raw('SELECT public.square(6) AS result;');
+
+    const {
+      rows: [{ result: product }]
+    } = await db.raw('SELECT utils.product(6, 7) AS result;');
+    const {
+      rows: [{ result: date }]
+    } = await db.raw('SELECT utils.get_date() AS result;');
 
     console.log(
       '\nList of table names in the database:\n',
@@ -28,8 +39,8 @@ const { connections } = require('../connections.sync-db.json');
     );
     console.log('\nCalculations:\n', {
       'Sum of 6 and 7': sum,
-      'Product of 6 and 7': product,
-      'Square of 6': square
+      'Square of 6': square,
+      'Product of 6 and 7': product
     });
     console.log('\nCurrent date time:', date);
 

examples/node-app-pg-ts/src/sql/function/public/sum.sql

@@ -2,7 +2,7 @@
 -- Calculate square of a number.
 --
 CREATE FUNCTION public.sum(INTEGER, INTEGER) RETURNS INTEGER
- AS 'SELECT $1 + $2;'
-    LANGUAGE SQL
-    IMMUTABLE
-    RETURNS NULL ON NULL INPUT;
+  AS 'SELECT $1 + $2;'
+  LANGUAGE SQL
+  IMMUTABLE
+  RETURNS NULL ON NULL INPUT;

examples/node-app-pg-ts/src/sql/function/utils/get_date.sql

@@ -0,0 +1,8 @@
+--
+-- Procedure that returns current date.
+--
+CREATE FUNCTION utils.get_date() RETURNS DATE
+  AS 'SELECT NOW()'
+  LANGUAGE SQL
+  IMMUTABLE
+  RETURNS NULL ON NULL INPUT;

examples/node-app-pg-ts/src/sql/function/utils/product.sql

@@ -2,7 +2,7 @@
 -- Calculate multiplication of two numbers.
 --
 CREATE FUNCTION utils.product(INTEGER, INTEGER) RETURNS INTEGER
- AS 'SELECT $1 * $2;'
-    LANGUAGE SQL
-    IMMUTABLE
-    RETURNS NULL ON NULL INPUT;
+  AS 'SELECT $1 * $2;'
+  LANGUAGE SQL
+  IMMUTABLE
+  RETURNS NULL ON NULL INPUT;

examples/node-app-pg-ts/src/sql/view/utils/vw_table_names.sql

@@ -3,8 +3,8 @@
 --
 CREATE VIEW utils.vw_table_names
 AS (
-  SELECT table_name
+  SELECT table_name AS name
   FROM information_schema.tables
   WHERE table_schema = 'public'
-    AND table_type = 'BASE TABLE'
+  AND table_type = 'BASE TABLE'
 );

examples/node-app-pg-ts/src/sql/view/utils/vw_user_names.sql

@@ -1,9 +1,9 @@
-
 --
 -- View to fetch server login names.
 --
 CREATE VIEW utils.vw_user_names
 AS (
-  SELECT DISTINCT usename as username
-  FROM pg_stat_activity WHERE usename IS NOT NULL
+  SELECT DISTINCT usename AS name
+  FROM pg_stat_activity
+  WHERE usename IS NOT NULL
 );

examples/node-app-pg-ts/sync-db.yml

@@ -9,7 +9,7 @@ sql:
   # Create objects in utils schema
   - schema/utils.sql
   - function/utils/product.sql
-  - procedure/utils/get_date.sql
+  - function/utils/get_date.sql
   - view/utils/vw_table_names.sql
   - view/utils/vw_user_names.sql