/**
* Example of using postgres-mcp with direct function imports
*
* This example demonstrates:
* 1. Importing specific functions from postgres-mcp
* 2. Connecting to databases and running operations directly
* 3. Managing database connections manually
*/
import {
initConnections,
closeConnections,
executeQuery,
executeCommand,
executeTransaction,
fetchTableSchema,
fetchAllTableSchemas,
getTableSchema,
getAllTableSchemas,
TableSchemaResult,
AllTableSchemasResult
} from '../src/index';
// Define database configurations
const databaseConfigs = {
main: {
host: 'localhost',
port: 5432,
database: 'my_database',
user: 'my_user',
password: 'my_password',
ssl: 'disable'
},
reporting: {
host: 'localhost',
port: 5432,
database: 'reporting_db',
user: 'reporter',
password: 'report_pass',
ssl: 'disable'
}
};
async function runDirectExamples() {
try {
console.log('Initializing database connections...');
// Initialize all database connections
initConnections(databaseConfigs);
// Give connections time to initialize
await new Promise(resolve => setTimeout(resolve, 1000));
// Example 1: Execute a query
console.log('\nExample 1: Execute a query');
try {
const result = await executeQuery(
'SELECT NOW() as current_time',
[],
'main'
);
console.log('Query result:', result);
} catch (error) {
console.error('Query failed:', error);
}
// Example 2: Execute a command
console.log('\nExample 2: Execute a command');
try {
const result = await executeCommand(
'CREATE TABLE IF NOT EXISTS temp_users (id SERIAL PRIMARY KEY, name TEXT, created_at TIMESTAMP DEFAULT NOW())',
[],
'main'
);
console.log('Command result:', result);
} catch (error) {
console.error('Command failed:', error);
}
// Example 3: Execute multiple commands in a transaction
console.log('\nExample 3: Execute a transaction');
try {
const result = await executeTransaction([
{
statement: 'INSERT INTO temp_users (name) VALUES ($1) RETURNING id',
params: ['User 1']
},
{
statement: 'INSERT INTO temp_users (name) VALUES ($1) RETURNING id',
params: ['User 2']
}
], 'main');
console.log('Transaction result:', result);
} catch (error) {
console.error('Transaction failed:', error);
}
// Example a: Get schema for single table
console.log('\nExample 4A: Fetch single table schema (original method)');
try {
const result: TableSchemaResult = await fetchTableSchema({
args: {
alias: 'main',
name: 'temp_users'
}
});
console.log('Table schema result:', result);
if (result.type === 'result') {
console.log('Schema:', result.schema);
} else {
console.error('Schema error:', result.error);
}
} catch (error) {
console.error('Schema fetch failed:', error);
}
// Example 4B: Fetch table schema (simplified method)
console.log('\nExample 4B: Fetch single table schema (simplified method)');
try {
const schema = await getTableSchema('temp_users', 'main');
console.log('Table schema:', schema);
} catch (error) {
console.error('Schema fetch failed:', error);
}
// Example 5A: Fetch all table schemas (original method)
console.log('\nExample 5A: Fetch all table schemas (original method)');
try {
const result: AllTableSchemasResult = await fetchAllTableSchemas({
args: {
alias: 'main'
}
});
console.log('All table schemas result:', result);
if (result.type === 'result') {
console.log('All schemas:', result.schemas);
} else {
console.error('Schema error:', result.error);
}
} catch (error) {
console.error('Schema fetch failed:', error);
}
// Example 5B: Fetch all table schemas (simplified method)
console.log('\nExample 5B: Fetch all table schemas (simplified method)');
try {
const schemas = await getAllTableSchemas('main');
console.log('All table schemas:', schemas);
} catch (error) {
console.error('Schema fetch failed:', error);
}
// Example 6: Using a different database connection
console.log('\nExample 6: Using a different database connection');
try {
const result = await executeQuery(
'SELECT current_database() as database',
[],
'reporting'
);
console.log('Query result from reporting DB:', result);
} catch (error) {
console.error('Query failed:', error);
}
// Clean up - close all database connections
console.log('\nClosing all database connections...');
await closeConnections();
console.log('\nExamples completed!');
} catch (error) {
console.error('Error running examples:', error);
await closeConnections();
}
}
// Run the examples
runDirectExamples();
