secure-bank

Example project for developing a banking api with golang, grpc and postgres

How to generate code

• Generate SQL CRUD with sqlc

make sqlc

• Generate DB mock with gomock:

make mock

• Create a new db migration

migrate create -ext sql -dir db/migration -seq <migration_name>

Database

Setup

• Install golang-migrate

cd db

make create-container
make createdb
make migrate-up

Table Plus installation

Installation Manual

# Add TablePlus gpg key
wget -qO - https://deb.tableplus.com/apt.tableplus.com.gpg.key | gpg --dearmor | sudo tee /etc/apt/trusted.gpg.d/tableplus-archive.gpg > /dev/null

# Add TablePlus repo
sudo add-apt-repository "deb [arch=amd64] https://deb.tableplus.com/debian/22 tableplus main"

# Install
sudo apt update
sudo apt install tableplus

golang-migrate

Install golang-migrate

Installation Manual

curl -s https://packagecloud.io/install/repositories/golang-migrate/migrate/script.deb.sh | sudo bash

sudo apt udpate
sudo apt install migrate

Initialization

mkdir -p db/migration

migrate create --ext sql --dir db/migration --seq init_schema

• This creates up an down migrations
• If we call migrate up it will upgrade the database to the last number of up migrations
• If we call migrate down it will downgrade the database from the last to the first of down migrations

Apply migrations

• Create migrations file with dbdiagram.io
• Copy the content to the up-migration
• Add the reverting commands to the down-migration

DROP TABLE IF EXISTS entries CASCADE;
DROP TABLE IF EXISTS transfers CASCADE;
DROP TABLE IF EXISTS accounts CASCADE;

CRUD Operations

sqlc

• Fully supports postgres
• Translates SQL to ideomatic golang std library for sql

Install sqlc

sudo snap install sqlc

sqlc version
sqlc help

Configure sqlc

• Initialize sqlc --> Will create a sqlc.yaml in your project folder

sqlc init

• Add postgresql engine and the correct file paths for queries and schema
• Remove cloud and database for using sqlc without the cloud

version: "2"
sql:
  - engine: "postgresql"
    queries: "./db/query/"
    schema: "./db/migration/"
    gen:
      go:
        package: "db"
        out: "./db/sqlc"
        sql_package: "pgx/v5"
        emit_json_tags: true
        emit_prepared_queries: false
        emit_interface: false
        emit_exact_table_names: false

• Write your own queries in SQL and generate code from these queries using sqlc generate

mockgen

mockgen installation

• Get the binary

go install github.com/golang/mock/mockgen@vX.X.X

• The binary will be installed to ~/go/bin
• Check if it is already available

which mockgen

• If not available, you have add the folder to PATH

# ~/.zshrc
# ...
export PATH="$PATH:$HOME/go/bin"
# ...

Create mocks

• Set sqlc option emit_interface to true -> make sqlc

mockgen -destination db/mock/store.go github.com/PfMartin/secure-bank/db/sqlc Store