I got error when try to run docker-compose up -d

Im just getting started with Golang and am trying to build go gin with docker-compose. Here is my Dockerfile

FROM golang:1.18

WORKDIR /docker-go

# pre-copy/cache go.mod for pre-downloading dependencies and only redownloading them in subsequent builds if they change
# COPY all file go ./

COPY ./app/main.go ./
COPY . /docker-go
# To initialize a project with go module, create go.mod

RUN go mod init shipping-go

# Add missing and/or remove unused modules
RUN go mod tidy

# This will bring all the vendors to your projects /vendor directory so that 
# you don't need to get the modules again if working from another machine on this project.
RUN go mod vendor

RUN go mod download && go mod verify

COPY . .
RUN go build -v -o /docker-go/app .

RUN chmod +x /docker-go
USER root

and my docker-compose

version: "3.7"
services:
  go-web:
    build:     
      context: ./
      dockerfile: Dockerfile
    restart: 'no'
    working_dir: /docker-go
    ports:
      - "8080:8080"
    entrypoint: ["./start.sh"]
    volumes:
      - ./:/docker-go

And i got error when i check logs container with command

docker logs learn-docker-go_go-web_1

/docker-go
go: cannot find main module, but found .git/config in /docker-go
    to create a module there, run:
    go mod init
/docker-go

its seem go can't find module file but i have install in Dockerfile. For Detail i push code in my repository here https://github.com/duyanh1904/learn-docker-go

Solution

There are multiple issues with your Dockerfile and docker-compose.yml and I have been unable to replicate the issue you are seeing (but your setup does not work for me either). A few of the problems I see are:

COPY . /docker-go will copy the current folder (including subfolders) into the image at /docker-go/. This will result in a folder /docker-go/app. The existence of this folder means that go build -v -o /docker-go/app . will store the executable as /docker-go/app/shipping-go (you are trying to execute a folder).
Your intention is for the executable to be in /docker-go but you then obscure that folder with a mount (./:/docker-go). As per the docs "If you bind-mount into a non-empty directory on the container, the directory’s existing contents are obscured by the bind mount.".
Your start.sh (not shown in the question) is not starting the executable (see the docs).
in main.go (also not shown in the question) replace router.Run("127.0.0.1:8080") with router.Run(":8080"). Listening on 127.0.0.1 means that only local connections will be accepted; within a container that means only connections from the container itself.

Here is a working setup to get you going (this is probably not optimal but should provide a starting point that will enable you to experiment further). Note that you need to make the above change in main.go first.

Dockerfile

FROM golang:1.18

WORKDIR /docker-go

# Note: A better solution would be to copy an existing go.mod into the image
RUN go mod init shipping-go
COPY ./app/main.go ./
# Determine required modules and download them
RUN go mod tidy
RUN go build -v -o /docker-go/app
RUN chmod +x /docker-go/app

docker-compose.yml

version: "3.7"
services:
  go-web:
    build:     
      dockerfile: Dockerfile
    restart: 'no'
    ports:
      - "8080:8080"
    command: ["./app"]