Executable not found in docker compose /bin/sh: 1: main: not found

Question

I am trying to run my restful api in docker but having issue with my golang executable it is always not found. Here is my Dockerfile

# Start from golang base image
FROM golang:1.15.2

#Set ENV
ENV DB_HOST=fullstack-mysql \                   
    DB_DRIVER=mysql \
    DB_USER=root \
    DB_PASSWORD=root \
    DB_NAME=link_aja \
    DB_PORT=3306 \
    APP_NAME=golang-linkaja \
    CGO_ENABLED=0 

# Copy the source from the current directory to the working Directory inside the container 
COPY . /usr/src/${APP_NAME}

# Move to working directory
WORKDIR /usr/src/${APP_NAME}

#install depedencies
RUN go mod download

# Build the application
RUN go build -o ${APP_NAME}

# Expose port 3000 to the outside world
EXPOSE 3000

#Command to run the executable
CMD ${APP_NAME}

And here is my docker-compose.yml

version: '3'
services:
  app:
    container_name: golang-linkaja
    build: .
    ports: 
      - 3000:3000 
    restart: on-failure
    volumes:
      - api:/usr/src/${APP_NAME}
    depends_on:
      - fullstack-mysql          
    networks:
      - fullstack


  fullstack-mysql:
    image: mysql:5.7
    container_name: full_db_mysql
    ports: 
      - 3306:3306
    environment: 
      - MYSQL_ROOT_HOST=${DB_HOST} 
      - MYSQL_USER=${DB_USER}
      - MYSQL_PASSWORD=${DB_PASSWORD}
      - MYSQL_DATABASE=${DB_NAME}
      - MYSQL_ROOT_PASSWORD=${DB_PASSWORD}
    volumes:
      - database_mysql:/var/lib/mysql
    networks:
      - fullstack
  
  phpmyadmin:
    image: phpmyadmin/phpmyadmin
    container_name: phpmyadmin_container
    depends_on:
      - fullstack-mysql
    environment:
      - PMA_HOST=fullstack-mysql #DB_HOST env must be the same with this
      - PMA_USER=${DB_USER}
      - PMA_PORT=${DB_PORT}
      - PMA_PASSWORD=${DB_PASSWORD}
    ports:
      - 9090:80
    restart: always
    networks:
      - fullstack


volumes:
  api:
  database_mysql:                  

# Networks to be created to facilitate communication between containers
networks:
  fullstack:
    driver: bridge

Everything works correctly except for the Go app itself, here is the error that I get

golang-linkaja     | /bin/sh: 1: golang-linkaja: not found

Could i get any help please? i'm new and still learning docker
Thanks in advance!
Update: here are the other things i've tried:
1.Changing CMD to CMD ["./usr/src/${APP_NAME}/${APP_NAME}"]
Return error golang-linkaja | sh: 1: /usr/src/golang-linkaja/golang-linkaja: not found
2.Changing to CMD [ "./golang-linkaja" ] and CMD [ "./${APP_NAME}" ]
Return error ERROR: for golang-linkaja Cannot start service app: OCI runtime create failed: container_linux.go:370: starting container process caused: exec: "./golang-linkaja": stat ./golang-linkaja: no such file or directory: unknown

Answer 1

You need to remove the volume - api:/usr/src/${APP_NAME} from your compose. You have already copied what you need in your Dockerfile. The volume(defined in compose) is overwriting all your data and hence your built binary is not found.

Just remove the volume and try to rebuild and start the container again .... and change your cmd to CMD [ "./${APP_NAME}" ]

Answer 2

In your Dockerfile, you try to run your executables without using ./ prefix, So OS search executable on system folders and can not find it. Add ./ beginning of your CMD or use the absolute path of the executable.

#Command to run the executable
CMD ./${APP_NAME}

or

#Command to run the executable
CMD /usr/src/${APP_NAME}