backend

CAST Backend

Prerequisites

• GoLang 1.16+
• PostgreSQL 14.1
• Flow CLI
  • Note: See below for how install v0.30.2 (required)

Local Development

Environment Variables

Copy .env.example to a new file .env.

cp .env.example .env

The correct values for IPFS_KEY and IPFS_SECRET can be found in the Dapper Collectives 1password, or you you can use your own by creating an account with Pinata.

Database

Install PSQL

• PostgreSQL 14.1
• via homebrew brew install postgresql

Configure Postgres DB User/PW

By default the postgres user has no password. Give it a password so we can connect with our application

sudo -i -u postgres
psql
CREATE USER postgres; # if postgres user doesnt exist
ALTER USER postgres PASSWORD 'admin';

Create flow_snapshot Database, and Test Database

sudo -i -u postgres
psql
CREATE DATABASE flow_snapshot;
CREATE DATABASE flow_snapshot_test;

NOTE: in some system configurations sudo -i -u postgres will return an error so you can run the following:

psql
CREATE USER postgres;
ALTER USER postgres PASSWORD 'admin';
ALTER USER postgres WITH SUPERUSER;
CREATE DATABASE flow_snapshot WITH OWNER = postgres;
CREATE DATABASE flow_snapshot_test WITH OWNER = postgres;

Install Migrate Tool

To run the make migrate scripts, you need to have the migrate CLI installed in your local path. Follow the steps here to install migrate on your machine.

Creating Migration Files

In flow-voting-tool:

migrate create -ext sql -dir migrations -seq my_migration_file

This will create two files, one for migrating up and one for migrating down. Please fill in both properly to make rolling back migrations easy, if necessary.

Migrating Up & Down

Migrate Up:

make migrateup

Migrate Down:

make migratedown

Migrating Up & Down for Test Database

The first time you run the tests, you'll need to migrate the test database.

Migrate Up:

make testmigrateup

Migrate Down:

make testmigratedown

Dealing with Dirty Schema Migrations

Reset Schema Migrations

UPDATE schema_migrations SET dirty = false

Testing

1. Run flow emulator from this top-level directory (the private key for the emulator-account in top level flow.json must match the private key hard-coded in the test suite eg. backend/cadence/V2/tests/flow.json). Install the flow CLI here
2. Run migrations against the test database (if migrations aren't up to date): make testmigrateup
3. Run the test suite: make test

Building & Running Docker Test Image

Build (To build locally, uncomment the COPY .env .env line in Dockerfile.test)

docker build . --file=Dockerfile.test -t vt-test

Run (To run locally, must have flow emulator running, and local PostgresDB):

docker run -it --network=host --rm --name vt-test vt-test:latest

Run the app

Before running the app you should:

1. Run flow emulator from this top-level directory (the private key for the emulator-account in top levelflow.json must match the private key hard-coded in the test suite eg. backend/cadence/V2/tests/flow.json). Install the flow CLI here
2. Run migrations against the database (if migrations aren't up to date): make migrateup

Go Executable

To build the binary & run it:

LINUX: make build_and_run
MACOS: make macrun

Alternatively:

go run ./main

The server runs on port 5001. Confirm that it is running by hitting https://localhost:5001/api in your browser.

Running Blockchain & Dev Wallet

To start a local blockchain & dev-wallet

npm run chain

Running via Docker

This is a good way to debug env related issues.

1. If you are connecting to a local PostgresDB, update DB_HOST in your .env file to host.docker.internal
2. Set ENV_NAME="DOCKER"

Finally,

make image # create the Docker image
make container # spin up a container from Docker image