I have a mysql database running with the following docker-compose.yml:
version: '3.3'
services:
db:
image: mysql:5.7
restart: always
environment:
MYSQL_DATABASE: 'demo'
# So you don't have to use root, but you can if you like
MYSQL_USER: 'user'
# You can use whatever password you like
MYSQL_PASSWORD: 'password'
# Password for root access
MYSQL_ROOT_PASSWORD: 'password'
ports:
# <Port exposed> : < MySQL Port running inside container>
- '3306:3306'
expose:
# Opens port 3306 on the container
- '3306'
# Where our data will be persisted
volumes:
- my-db:/var/lib/mysql
networks:
- backend
networks:
backend:
driver: bridge
# Names our volume
volumes:
my-db:
$ docker-compose build
$ docker-compose up
I have a basic golang rest api with the following Dockerfile:
# Start from golang:1.12-alpine base image
FROM golang:1.12-alpine
# Adding git, bash and openssh to the image
RUN apk update && apk upgrade && \
apk add --no-cache bash git openssh
# Set the Current Working Directory inside the container
WORKDIR /app
# Copy the source from the current directory to the Working Directory inside the container
COPY . .
RUN go get -d github.com/gorilla/mux
RUN go get -d github.com/go-sql-driver/mysql
RUN go get -d github.com/golang-migrate/migrate
RUN go get -d github.com/golang-migrate/migrate/database/mysql
RUN go get -d github.com/golang-migrate/migrate/source/file
# Build the Go app
RUN go build -o main .
# Expose port 8080 to the outside world
EXPOSE 8080
# Run the executable
CMD ["./main"]
and the following function is called:
func CreateDatabase() (*sql.DB, error) {
serverName := "localhost:3306"
user := "user"
password := "password"
dbName := "demo"
connectionString := fmt.Sprintf("%s:%s@tcp(%s)/%s?charset=utf8mb4&collation=utf8mb4_unicode_ci&parseTime=true&multiStatements=true", user, password, serverName, dbName)
db, err := sql.Open("mysql", connectionString)
if err != nil {
return nil, err
}
if err := migrateDatabase(db); err != nil {
return db, err
}
return db, nil
}
$ docker run -p 80:8080 --network=<appname>-mysql_backend <imageid>
$ Database connection failed: %sdial tcp 127.0.0.1:3306: connect: connection refused
I cannot get the api to establish a database connection with the database container?
