docs: README and CLI documentation

README.md

@@ -1,2 +1,51 @@
 # message-api
-
+
+[![Build](https://github.com/shoriwe/message-api/actions/workflows/build.yaml/badge.svg)](https://github.com/shoriwe/message-api/actions/workflows/build.yaml)
+[![codecov](https://codecov.io/gh/shoriwe/message-api/branch/main/graph/badge.svg?token=RU4KKCQPUV)](https://codecov.io/gh/shoriwe/message-api)
+[![Go Report Card](https://goreportcard.com/badge/github.com/shoriwe/message-api)](https://goreportcard.com/report/github.com/shoriwe/message-api)
+![GitHub go.mod Go version](https://img.shields.io/github/go-mod/go-version/hidromatologia-v2/stations)
+
+REST API for [message-app](https://github.com/shoriwe/message-app)
+
+## Documentation
+
+| File                                             | Description                                |
+| ------------------------------------------------ | ------------------------------------------ |
+| [docs/spec.openapi.yaml](docs/spec.openapi.yaml) | OpenAPI documentation for the REST service |
+| [docs/CLI.md](docs/CLI.md)                       | CLI documentation for the main binary      |
+
+## Running
+
+### Docker
+
+```shell
+docker pull ghcr.io/shoriwe/message-api:latest
+```
+
+### Docker compose
+
+Make sure to customize the [example.env](example.env) file. Then:
+
+```shell
+docker compose up -d
+```
+
+### Binary
+
+You can find pre-compiled binaries at the [releases](https://github.com/shoriwe/message-api/releases) section.
+
+```shell
+export SECRET = "MY_SECRET"
+export FIREBASE_PROJECT_ID = "MY_FIREBASE_PROJECT"
+export FIREBASE_CONFIGURATION_FILE = "firebase-adminsdk.json"
+export DATABASE_FILE = "database.db"
+
+message-api :5000
+```
+
+#### Building from source
+
+```shell
+go install github.com/shoriwe/message-api@latest
+```
+

docs/CLI.md

@@ -0,0 +1,19 @@
+# CLI
+
+Documentation for the CLI
+
+## Environment variables
+
+| Variable                      | Description                                          |
+| ----------------------------- | ---------------------------------------------------- |
+| `SECRET`                      | Secret for the JWT engine                            |
+| `FIREBASE_PROJECT_ID`         | Project ID of the Firebase APP                       |
+| `FIREBASE_CONFIGURATION_FILE` | Firebase configuration file specific for the backend |
+| `DATABASE_FILE`               | SQLite file path to use                              |
+
+## Command
+
+```shell
+message-api LISTEN_ADDR [LISTEN_ADDR [LISTEN_ADDR [...]]]
+```
+