Deploying a Go Fiber application to Fly

In this tutorial you will learn how to deploy a containerized Go Fiber application to Fly.

The final code of this article can be found here.

#Prerequisites

• A Fly account
• A computer with Go, Docker, and Flyctl (the Fly CLI)

#Creating the application

go mod init hello-world

go get github.com/gofiber/fiber/v2

./src/application.go

package main

import (
"github.com/gofiber/fiber/v2"
"log"
"math/rand"
"strconv"
)

const port = 8080

func main() {
    application := fiber.New()

    application.Get("/", func(c *fiber.Ctx) error {
        return c.JSON(&fiber.Map{
            "message": "Hello, World!",
        })
    })

    application.Get("/random", func(c *fiber.Ctx) error {
        return c.JSON(&fiber.Map{
            "number": rand.Intn(10),
        })
    })

    log.Fatalln(application.Listen(":" + strconv.Itoa(port)))
}

To run the application locally:

go run ./src/application.go

#Containerizing the application

Dockerfile

FROM golang:1.18-alpine
WORKDIR /usr/src/app
COPY go.mod ./
COPY go.sum ./
RUN go mod download
COPY ./src ./src
RUN go build -o ./bin/hello-world ./src
EXPOSE 8080
CMD [ "./bin/hello-world" ]

To build and run the container locally:

docker build . -t hello-world
docker run -dp 8080:8080 hello-world

#Deploying the application

1. fly launch to prepare your fly.toml file, containing your project settings. Inside the fly.toml file, ensure the service's internal_port (8080 by default) matches the port exposed by your container.
2. fly deploy to deploy your application.
3. fly open to open the deployed application in your browser.

#Cleaning up

fly destroy your-unique-app-id -y removes your application from the Fly platform.

That's all! Don't forget to delete the application once you're done testing.

The final code of this article can be found here.