pg-altergen/src/commands/generate.js

A Node.js CLI tool for managing PostgreSQL schema changes by organizing database objects in SQL files and generating ordered migration scripts with automatic dependency resolution.

const fs = require('fs');

// Example requires – adapt to your actual locations
const files = require('../utils/files');
const schemas = require('../processors/schemas');
const tables = require('../processors/tables');
const extensions = require('../processors/extensions');
const types = require('../processors/types');
const others = require('../processors/others');
const inserts = require('../processors/inserts');
const updates = require('../processors/updates');
const indexes = require('../processors/indexes');
const migrations = require('../processors/migrations');


/**
 * generateCommand:
 *  1) Collect/scan all relevant SQL parts (schemas, tables, etc.)
 *  2) Construct the final “alter” script
 *  3) Write to config.output_file
 */
async function generateCommand(config) {
    let alter = '';

    // SCHEMAS
    const schema_files = files.listfiles('schemas', 'all');
    schemas.process(schema_files);

    // EXTENSIONS
    const extension_files = files.listfiles('extensions', 'all');
    extensions.process(extension_files); // Process extension files

    // TYPES
    const type_files = files.listfiles('types', 'all');
    types.process(type_files); // Process type files

    // TABLES
    const table_files = files.listfiles('tables', 'all');
    tables.process(table_files);

    // VIEWS 
    const view_files = files.listfiles('views', 'all');
    others.process('views', view_files);

    // FUNCTIONS
    const function_files = files.listfiles('functions', 'all');
    others.process('functions', function_files);

    // PROCEDURES
    const procedure_files = files.listfiles('procedures', 'all');
    others.process('procedures', procedure_files);

    // TRIGGERS TODO
    const trigger_files = files.listfiles('triggers', 'all');

    // SEQUENCES TODO
    const sequence_files = files.listfiles('sequences', 'all');

    // INSERTS TODO
    const insert_files = files.listfiles('inserts', 'all');
    let inserts_res = await inserts.generate(insert_files);

    // UPDATES TODO
    const update_files = files.listfiles('updates', 'all');
    let updates_res = await updates.generate(update_files);

    // MIGRATIONS
    const migration_files = files.listfiles('migrations', 'all');
    let migrations_res = await migrations.generate(migration_files);


    // GENERATE
    let schemas_res = schemas.generate();
    let extensions_res = extensions.generate(); 
    let types_res = types.generate();
    let tables_res = tables.generate();
    let other_res = others.generate();
    let drop_res = others.drop();
    let indexes_res = indexes.generate(table_files);

    // // INSERTS
    // const insertFiles = files.listfiles('inserts', 'all');
    // alter += insert.generate(insertFiles);

    // Merge portions
    alter += [
        // CREATE SCHEMAS
        ...schemas_res,

        // CREATE EXTENSIONS (early on, as other objects might depend on them)
        ...extensions_res,

        // CREATE TYPES (before tables that might use them)
        ...types_res,

        // DROP
        ...tables_res.drop_constraints,
        ...drop_res,
        ...indexes_res.drop_indexes,

        // CREATE
        ...tables_res.create,
        ...migrations_res,
        ...tables_res.constraints,
        ...indexes_res.create_indexes,
        ...other_res,
        ...inserts_res,
        ...updates_res,

    ].join('\n-- step\n') + '\n-- step\n';


    // Final version label + note
    const version = require('../../package.json').version;
    const now = new Date().toISOString();
    let note =
        `-- This file was generated by pg-altergen v${version}\n-- ${now}\n\n` +
        `-- with config:\n\n-- The MIT License (MIT)\n-- © ${new Date().getFullYear()} Marek Mráz <info@marek-mraz.com>\n\n`;

    // Copy config minus the Postgres password or other sensitive data
    const config_copy = { ...config };
    delete config_copy.postgres;

    for (let key in config_copy) {
        note += `--   ${key}: ${JSON.stringify(config_copy[key])}\n`;
    }

    // Write everything to disk
    files.writeFileRecursive(config.output_file, note + '\n' + alter + '\n' + note);
    console.log(`Generated SQL file: ${config.output_file}`);

    if (config.create_drop_columns_file && config.drop_columns_file) {
        let drop_not_included_columns = tables.drop_not_included_columns();
        files.writeFileRecursive(config.drop_columns_file, `-- DROP NOT INCLUDED COLUMNS\n${note}\n${drop_not_included_columns} \n ${note}`);
    }
}




module.exports = { generateCommand };