pg-notify
Configure and subscribe to Postgres Notify automatically for a given set of tables.
| Param | Type | Default | Description |
|---|---|---|---|
| client | object |
node-postgres Client instance | |
| configObject | object |
Configuration object | |
| configObject.schema | string |
"public" |
Name of the schema where the tables exists. |
| configObject.functionName | string |
"notify_table_change" |
Name of the function to use notify. |
| configObject.channelName | string |
"notify_table_change_channel" |
Name of the channel where the function will notify. |
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pg-notify
- [~Subscribe to all database events of a given list of tables(tables)](#module_pg-notify..Subscribe to all database events of a given list of tables) ⇒
Promise - [~Create the functions and triggers to configure pg-notify.(tables)](#module_pg-notify..Create the functions and triggers to configure pg-notify.) ⇒
Promise
- [~Subscribe to all database events of a given list of tables(tables)](#module_pg-notify..Subscribe to all database events of a given list of tables) ⇒
pg-notify~Subscribe to all database events of a given list of tables(tables) ⇒ Promise
Kind: inner method of pg-notify
Returns: Promise - a promise wich resolves an NodeJS EventEmitter
| Param | Type | Description |
|---|---|---|
| tables | Array.<string> |
An array of table names to listen |
Example
const { Client } = require('pg');
const pgNotify = require('@becual/pg-notify');
let eventHandler = evt => {
console.log(JSON.stringify(evt, null, 4));
};
(async () => {
// Use your connection string
const client = new Client({ connectionString: process.env.PG_CONNECTION_STRING });
// Choose your tables to listen
const tables = ['customer', 'order_detail'];
try {
// Connect client
await client.connect();
// By default schema is public
const sub = await pgNotify(client, {schema: 'mySchema'}).subscribe(tables);
// Listen for changes
sub.on('INSERT', eventHandler);
sub.on('UPDATE', eventHandler);
sub.on('DELETE', eventHandler);
}
catch(error) {
console.log(error.message);
}
finally {
await client.end();
}
})();
pg-notify~Create the functions and triggers to configure pg-notify.(tables) ⇒ Promise
Kind: inner method of pg-notify
Returns: Promise - A promise that will implement the pg-notify config.
| Param | Type | Description |
|---|---|---|
| tables | Array.<string> |
The list of tables to create pg notify configuration. |
Example
const { Client } = require('pg');
const pgNotify = require('@becual/pg-notify');
(async () => {
const client = new Client({ connectionString: process.env.PG_CONNECTION_STRING });
const tableList = ['customer', 'order_detail'];
try {
// Try to generate configuration
await client.connect();
await pgNotify(client, {schema: 'mySchema'}).config(tableList);
}
catch(error) {
// Show errors
console.log(error.message);
}
finally {
// Close connection
await client.end();
}
})();