Resell Backend

An open-sourced backend service for Resell.

Setup

Make sure that npm installed (nvm is recomended to manage node versions.)
Depending on preference, either run yarn install or npm install to ensure all required dependencies are installed. Copy the .env_template to either a .env file , and update with necessary credentials. Sourcing the file is not necessary.

In addition, this codebase requires these files in the project root to run:

• .env → Copy from .env_template and fill with your database credentials, Firebase configs, and API keys
• resell.pem → Private key file required for authentication
• a resell firebase json file → Firebase service account key for connecting to Firebase

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Installing Postgres

Steps to install Postgres:

macOS (via Homebrew)

1. Update Homebrew

   brew update
   

2. Install and start

   brew install postgresql
   brew services start postgresql
   

3. Initialize DB

   initdb /usr/local/var/postgres
   

4. Create User
   In order to run the create and alter commands, you must be inside psql.

   psql postgres
   create user postgres with password 'postgres';
   alter user postgres with superuser;
   create database "resell-dev";
   

Use the \l command to see if the "resell-dev" is owned by user postgres. If instead it is owned by another root user, drop the database via: drop database "resell-dev"; and login to psql via psql postgres postgres Then, create the database again, and it should be owned by user postgres.

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Windows (via Installer)

1. Download PostgreSQL from https://www.enterprisedb.com/downloads/postgres-postgresql-downloads
2. During install, include Command Line Tools and pgAdmin 4. Set the default password for the postgres user (e.g., postgres).
3. Add PostgreSQL’s bin folder to PATH:

   C:\Program Files\PostgreSQL\<version>\bin
   

4. Open Command Prompt or PowerShell:

   psql -U postgres -d postgres
   

5. Inside psql:

   CREATE USER postgres WITH PASSWORD 'postgres';
   ALTER USER postgres WITH SUPERUSER;
   CREATE DATABASE "resell-dev";
   

6. Verify:

   \l
   

   If resell-dev is owned by another user:

   DROP DATABASE "resell-dev";
   CREATE DATABASE "resell-dev" OWNER postgres;
   

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Connecting to DB

In order to connect to the database, follow these steps:

macOS

1. Install Homebrew

   /bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"
   

2. Update Homebrew to ensure you have the latest information

   brew update
   

3. Install pgAdmin

   brew install --cask pgadmin4
   

Open pgAdmin and configure the connection using the defined user and password.

Windows

pgAdmin is installed by default with PostgreSQL. Launch it from the Start Menu and configure a new connection with:

• Host: localhost
• Port: 5432
• Username: postgres
• Password: postgres

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Installing pgvector

This codebase uses the pgvector extension.

macOS

brew install pgvector
psql -U postgres -d resell-dev -c "CREATE EXTENSION vector;"

Windows (manual install)

1. Download/build pgvector from GitHub releases.
2. Copy files:
   • vector.control → C:\Program Files\PostgreSQL\<version>\share\extension\
   • vector.dll → C:\Program Files\PostgreSQL\<version>\lib\
3. Restart PostgreSQL service.
4. In psql:

   CREATE EXTENSION vector;
   

Docker (cross-platform alternative)

docker run -d --name pgvector -e POSTGRES_PASSWORD=postgres -p 5432:5432 ankane/pgvector

Update .env:

DATABASE_URL=postgres://postgres:postgres@localhost:5432/resell-dev

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Create/Update Objects in Postgres DB

To create/update the database objects, run:

npm run db:migrate

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Migration debugging (last resort)

If you are encountering any migrations errors, use this as a last resort!

1. Log into psql and run

   drop database "resell-dev"
   

   This will delete all data in your database as well. Make sure you do not have any important data in your database.

2. Create the database again via.

   create database "resell-dev"
   

3. Delete all of the migration files in the "migrations" folder

4. Create a new migration file titled "init" via.

   npm run db:migrate:generate init
   

5. Run the migration

   npm run db:migrate
   

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Database Setup for Local Development

Option 1: Import Dev Database (Recommended)

To work with the same data as the dev environment, you can import a copy of the dev database into your local setup. This works with both Docker and native postgres installations.

Step 1: Create Database Dump from Dev Environment

First, update the dev database connection details in scripts/dump-dev-db.sh:

DEV_DB_HOST="localhost"
DEV_DB_NAME="resell-dev"
DEV_DB_USERNAME="postgres"

Then create the dump:

./scripts/dump-dev-db.sh

Step 2: Import into Local Database

The import script automatically detects your postgres setup (Docker or native) and imports accordingly:

./scripts/import-dev-data.sh

What these commands do:

The first command will:

• Detect your my_postgres Docker container
• Create a dump from your resell-dev database
• Save it to dumps/dev_db_dump_[timestamp].sql

The second command will:

• Find the dump file you just created
• Import it into your resell-test database
• Show you a summary of imported data

Manual Override Options:

• Force Docker: FORCE_DOCKER=1 ./scripts/import-dev-data.sh
• Force Native: FORCE_NATIVE=1 ./scripts/import-dev-data.sh

Supported Setups:

• Docker containers (like my_postgres)
• Native PostgreSQL installations (Homebrew, apt, etc.)
• Custom PostgreSQL setups on localhost:5432

Option 2: Use Data Seeder (Alternative)

This project includes a mechanism for seeding consistent data for the dev environment using TypeORM and typeorm-seeding. The seeders generate users, posts, feedback, reviews, reports, and requests, making sure all devs work with the same data set.

Running the Seeder

To seed the database for dev, use the following command:

npm run db:seed

The seeding script checks the environment to ensure it only runs in the dev environment. If the environment variable IS_PROD is set to "true", the seeding process will be skipped to prevent accidental execution in prod.

Configuration

The factories and seeders are configured to generate consistent data that is shared across all dev environments.

• Factories: Each entity has a corresponding factory that generates consistent data using an index to differentiate between records
• Seeders: The main seeder script (SeedInitialData) handles the creation of all entities, ensuring relationships are properly established

Notes

• Resetting Data: The seeder script will delete all existing data for users, posts, feedback, reviews, reports, and requests before creating new records. This ensures a clean slate for each run
• Relationships: Factories take into consideration entity relationships, such as assigning posts to users, feedback entries to users, and creating reports and reviews between users and posts