134 lines
4.5 KiB
Markdown
134 lines
4.5 KiB
Markdown
## JS DB Connector Service Guide
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This set of modules is intended to serve as a general purpose toolkit for building Node.js applications with a database-type agnostic SQL backend. The audience at creation is myself, as I wanted a reusable module for communicating with my SQL backends in Node.js projects.
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## Features
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At the moment, CRUD operations against Microsoft SQL Server and MariaDB servers are supported. I plan to implement support for interoperability with Postgres, Oracle, and MongoDB as well to provide the most possible utility in this package. An example implementation server.js:
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```javascript
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// server.js
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require('dotenv').config();
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const express = require('express');
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const app = express();
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const queryExecutor = require('./services/dbconnector/queryExecutor');
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const cors = require('cors');
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app.use(express.json());
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app.use(cors());
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/**
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* Example route to demonstrate CRUD operations.
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*/
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app.post('/api/query', async (req, res) => {
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try {
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const { table, operation, params } = req.body;
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const result = await queryExecutor.executeQuery(table, operation, params);
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res.status(200).json(result);
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} catch (err) {
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console.error('Error executing query:', err);
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res.status(500).json({ error: err.message });
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}
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});
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const PORT = process.env.PORT || 3100;
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app.listen(PORT, () => {
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console.log(`Server is running on port ${PORT}`);
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});
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```
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Additionally, here's an example client.js script to test the database connector:
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```javascript
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// client.js
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const axios = require('axios');
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const generateUUID = require('uuid').v4;
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async function testQuery(table, operation, params) {
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try {
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const response = await axios.post('http://localhost:3100/api/query', {
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table,
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operation,
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params
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});
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console.log(response.data);
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} catch (error) {
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console.error('Error executing query:', error.response ? error.response.data : error.message);
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}
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}
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// Example usage:
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(async () => {
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// CREATE: Ensure all required fields are present
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const ID1 = generateUUID();
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const ID2 = generateUUID();
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const ID3 = generateUUID();
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await testQuery('Test', 'CREATE', {
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Name: 'Test Item',
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Text: 'A sample item created with ID: ' + ID1,
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ID: ID1
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// Add other necessary fields here based on your schema
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});
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await testQuery('Test', 'CREATE', {
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Name: 'Test Item',
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Text: 'A sample item created with ID: ' + ID2,
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ID: ID2
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// Add other necessary fields here based on your schema
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});
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await testQuery('Test', 'CREATE', {
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Name: 'Test Item',
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Text: 'A sample item created wth ID: ' + ID3,
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ID: ID3
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// Add other necessary fields here based on your schema
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});
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await testQuery('Test', 'CREATE', {
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Name: 'Test Item',
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Text: 'A sample item created with ID: ' + ID4,
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ID: ID4
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// Add other necessary fields here based on your schema
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});
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// UPDATE: Ensure both the ID and at least one field to update are present. ID must be the LAST field.
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await testQuery('Test', 'UPDATE', {
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Name: 'Tested item name',
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Text: 'Updated item text successfully for item: ' + ID2,
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ID: ID2
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});
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// READ: Ensure the ID is present
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await testQuery('Test', 'READ', {
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ID : ID1
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} );
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// READ: See all rows in a table
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await testQuery('Test', 'READ', {
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Name: 'Tested item name',
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});
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// READ: See all rows in a table
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await testQuery('Test', 'READ', {
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partialMatch: true,
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Name: 'Test',
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});
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// DELETE: Ensure the ID is present
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await testQuery('Test', 'DELETE', {
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ID: ID3
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});
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})();
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```
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The following environment variables are used to control the operation of the DB connector:
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```
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DB_USER= # A user with permissions to manage the database
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DB_PASSWORD= # Password for DB_USER
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DB_SERVER= # Hostname or IP of the database server
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DB_PORT= # Port if not using default for the database type
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DB_DATABASE= # Database to be used. As written, only a single database is supported
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DB_TYPE= # MSSQL and MARIADB are implemented. ORACLEDB and POSTGRES are planned.
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DB_TRUST_CERT= # Trust the local system SSL certificate, useful for developing against MSSQL server.
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```
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## Testing
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To test the function of these modules, run "node server.js" in the project root, and post to http://localhost:3100/api/query. You can instead run client.js to automatically attempt each query type against the default server URL. |