Wire Web Application Demo
What is this? This is a simple webserver that just serves a visitor counter and its uptime seconds. It is built using Go, Postgres, and structured using dependency injection via Google Wire.
Buy why though? Because it serves as a good example for the future, for myself and others. The DI "modules" (config, log, db, etc) are fully-fledged and feature good unit testing and environment-based setup. They are ready to be copy-pasted to other projects, or used as reference points.
Some rationale and discussion behind how/why this was put together can be found in a blog post here.
Setup and running
Building. The code is built using Go 1.12 and Go modules. All you need to do to build it is:
go build
To re-generate wire_gen.go, use:
go generate
Testing. To run the unit tests and see coverage:
go test ./... -cover
On Windows, ignore any UAC port opening warning that comes up.
Environment. The runtime is parameterized via environment variables:
PORT- the port to serve the webserver on (optional; default=8080)DATABASE- the PostgreSQL connection string for its database (required)DEBUG- true/false toggle for debug logging (optional; default=false)
Database setup. The code bootstraps its own schema, so you just need to provide it with a database. An easy Docker-based way to do this would be:
docker run -p 5432:5432 postgres:latest
docker run --net=host -it postgres:latest psql postgres://postgres@localhost:5432
> CREATE DATABASE demo;
This would result in this connection string to be set as DATABASE (note the sslmode parameter):
postgres://postgres@localhost:5432/demo?sslmode=disable
Endpoints.
/uptime- displays the seconds since the server got started/counter- increments and displays a visitor counter from the database