postgres-to-mongo

library2.1.0jsnpmunverified

A framework for converting PostgreSQL databases to MongoDB. Current version 2.1.0, with ongoing maintenance. It provides a schema-mapping approach to translate relational structures (tables, relationships, constraints) into MongoDB collections and documents. Key differentiators: supports complex type conversions, custom mapping rules, and preserves data integrity. Release cadence is irregular, with version 2.x having breaking changes from 1.x. Primarily used for one-time migrations or ETL pipelines.

database

npm install postgres-to-mongo

github ↗package ↗homepage ↗

INSTALL

IMPORT

SIG · POSTGRES-TO-MONGO

postgres-to-mongo

databasejavascriptv2.1.0

harness data pending

Install & Compatibility

Where this runs

No compatibility data collected yet for this library.

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

convert

✓ import { convert } from 'postgres-to-mongo'

✗ const convert = require('postgres-to-mongo')

ESM-only since v2.0.

MappingConfig

✓ import type { MappingConfig } from 'postgres-to-mongo'

✗ const { MappingConfig } = require('postgres-to-mongo')

Only available as a type; cannot be imported as a value.

Connects to PostgreSQL and MongoDB, converts specified tables to collections using mapping configuration.

import pg from 'pg'; import { MongoClient } from 'mongodb'; import { convert } from 'postgres-to-mongo'; const pgClient = new pg.Client({ connectionString: process.env.PG_URL ?? '' }); const mongoClient = new MongoClient(process.env.MONGO_URL ?? ''); async function main() { await pgClient.connect(); await mongoClient.connect(); const config = { tableMapping: { 'users': { collection: 'users', primaryKey: 'id' }, 'orders': { collection: 'orders', primaryKey: 'id' } } }; const result = await convert(pgClient, mongoClient, config); console.log(`Converted ${result.totalDocuments} documents`); await pgClient.end(); await mongoClient.close(); } main().catch(console.error);

Debug

Known issues

breakingv2.0.0: Switched from CommonJS to ESM; synchronous API replaced with async/await.

fix

Update imports to use ESM syntax and wrap calls in async functions.

affects: >=2.0.0

deprecatedv2.0.0: The old pg-promise integration is deprecated; use 'pg' package with config objects.

fix

Replace pg-promise usage with 'pg' Client and pass config as second argument.

affects: >=2.0.0

gotchaPostgreSQL arrays are converted to MongoDB arrays, but nested arrays may not be flattened correctly.

fix

Manually handle nested arrays by providing a custom type transformer in the mapping config.

affects: <=2.1.0

Errors

Common errors & fixes

TypeError: convert is not a function

Using CommonJS require() for an ESM-only package.

fix

Use 'import { convert } from "postgres-to-mongo";' and ensure project is configured for ESM.

Error: Mapping config is required

Calling convert() without a mapping configuration object.

fix

Provide a config object with at least 'tableMapping' property.

Error: Relation not found

Referencing a table name that does not exist in the source PostgreSQL database.

fix

Check the table name in the config matches actual table names in PostgreSQL.

Upgrade

Version history

2.1.0latest on npm

Audit

Dependencies

No dependency data recorded yet.

Agent activity

8 hits · last 30 days

node

Resources

githubhttps://github.com/taicho/postgres-to-mongo ↗

packagepostgres-to-mongo ↗

homepagehttps://github.com/taicho/postgres-to-mongo#readme ↗