52 lines
2.4 KiB
Markdown
52 lines
2.4 KiB
Markdown
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express-myconnection
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============
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Connect/Express middleware provides a consistent API for MySQL connections during request/response life cycle. It supports three different strategies of managing db connections: ` single ` for a singleton connection on an app instance level, `pool` based connections, and a new connection per each `request`. It’s also capable of auto closing/releasing connections if configured either with `pool` or `request`. It uses [node-mysql](https://github.com/felixge/node-mysql) as a MySQL driver.
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### Strategies
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* `single` - creates single database connection for an application instance. Connection is never closed. In case of disconnection it will try to reconnect again as described in [node-mysql docs](https://github.com/felixge/node-mysql).
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* `pool` - creates pool of connections on an app instance level, and serves a single connection from pool per request. The connections is auto released to the pool at the response end.
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* `request` - creates new connection per each request, and automatically closes it at the response end.
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### Usage
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Configuration is straightforward and you use it as any other middleware. First param it accepts is a [node-mysql](https://github.com/felixge/node-mysql) module, second is a db options hash passed to [node-mysql](https://github.com/felixge/node-mysql) module when connection or pool are created. The third is string defining strategy type.
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// app.js
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...
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var mysql = require('mysql'), // node-mysql module
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myConnection = require('express-myconnection'), // express-myconnection module
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dbOptions = {
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host: 'localhost',
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user: 'dbuser',
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password: 'password',
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port: 3306,
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database: 'mydb'
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};
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app.use(myConnection(mysql, dbOptions, 'single');
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...
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**express-myconnection** extends `request` object with `getConection(callback)` function, this way connection instance can be accessed anywhere in routers during request/response life cycle:
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// myroute.js
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...
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module.exports = function(req, res, next) {
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...
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req.getConnection(function(err, connection) {
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if (err) return next(err);
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connection.query('SELECT 1 AS RESULT', [], function(err, results) {
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if (err) return next(err);
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results[0].RESULT;
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// -> 1
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res.send(200);
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});
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});
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...
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}
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...
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