sbda-ledger

README

Ledger

Backend for a social expenses ledger for groups of friends.

In this system, users are part of groups; a user can add an expense to the group, specifying how the expense has to be split. At any time, a user can request its balance, that will be the outstanding credits and debits for that users inside the group.

API documentation is available as OpenAPI/Swagger spec.

Prerequisites

• Docker
• docker-compose
• GNU Make
• Go 1.12+
  • Optionals:
  • golang-migrate (for manual sql migration)
  • golangci-lint as linter

Tests

End-to-end

Integration tests (e2e) are described in e2e directory. Tests cover all cases, including data structure and routes validation.

• Start environment with docker-compose start
• Start back-end API with make run
• Run tests with make e2e

Unit

I didn't have much time to cover code with unit tests, so most effort was done on integration testing. Integration tests cover all cases that could be covered by unit tests, so I don't think that it's critical.

Usage

Development

• Start DB and Redis containers with docker-compose start
  • Pre-create containers before start using docker-compose up -d (one time operation)
• make run

Migrations

Default location for migrations is db/migrations. Use make new-migration to create a new migration.

Use LGR_NO_MIGRATION environment variable to omit on-start migration.

Production

Use make to build the project. Output binary will be located at target directory.

Configuration

The service can be configured using environment variables, or a config file.

Use -c flag to provide path to a config file.

Environment variables

See config.go for more options.

Name	Type	Defaults	Description
LGR_HTTP_ADDR	string	:8800	Interface to listen by HTTP server
LGR_DB_ADDRESS	string	postgres://localhost:5432/ledger	Postgres DB address (URL or DSN)
LGR_REDIS_ADDRESS	string	localhost:6379	Redis server address
LGR_REDIS_USER	string	-	Redis username
LGR_REDIS_PASSWORD	string	-	Redis password
LGR_REDIS_DB	int	-	Redis database number
LGR_MIGRATIONS_DIR	string	db/migrations	Path to directory containing migration scripts
LGR_VERSION_TABLE	string	schema_migrations	Name of a table, which contains database version
LGR_SCHEMA_VERSION	int	-	Force set schema version (dangerous)
LGR_NO_MIGRATION	bool	false	Skip database migration