Set up a dev environment
Dev Environments is changing
We’re working hard to make Dev Environments work even better for you and your teams. In the coming months, we’ll be introducing a new vision for Dev Environments.
In the mean time, it may take us longer to respond to requests for support.
Changes to Dev Environments with Docker Desktop 4.13
Docker has simplified how you configure your dev environment project. All you need to get started is a
compose-dev.yamlfile. If you have an existing project with a
.docker/folder this is automatically migrated the next time you launch.
If you are using
.docker/docker-compose.yaml, we move it to
../compose-dev.yaml. If you are using
.docker/config.json, we create a
../compose-dev.yamlfile with a single service named “app”. It is configured to use the image or Dockerfile referenced in the JSON as a starting point.
To set up a dev environment, there are additional configuration steps to tell Docker Desktop how to build, start, and use the right image for your services.
Dev Environments use an
compose-dev.yaml file located at the root of your project. This file allows you to define the image required for a dedicated service, the ports you’d like to expose, along with additional configuration options.
The following is an example
version: "3.7" services: backend: build: context: backend target: development secrets: - db-password depends_on: - db db: image: mariadb restart: always healthcheck: test: [ "CMD", "mysqladmin", "ping", "-h", "127.0.0.1", "--silent" ] interval: 3s retries: 5 start_period: 30s secrets: - db-password volumes: - db-data:/var/lib/mysql environment: - MYSQL_DATABASE=example - MYSQL_ROOT_PASSWORD_FILE=/run/secrets/db-password expose: - 3306 proxy: build: proxy ports: - 8080:80 depends_on: - backend volumes: db-data: secrets: db-password: file: db/password.txt
In the yaml file, the build context
backend specifies that that the container should be built using the
development stage (
target attribute) of the Dockerfile located in the
backend directory (
development stage of the Dockerfile is defined as follows:
# syntax=docker/dockerfile:1 FROM golang:1.16-alpine AS build WORKDIR /go/src/github.com/org/repo COPY . . RUN go build -o server . FROM build AS development RUN apk update \ && apk add git CMD ["go", "run", "main.go"] FROM alpine:3.12 EXPOSE 8000 COPY --from=build /go/src/github.com/org/repo/server /server CMD ["/server"]
development target uses a
golang:1.16-alpine image with all dependencies you need for development. You can start your project directly from VS Code and interact with the others applications or services such as the database or the frontend.
In the example, the Docker Compose files are the same. However, they could be different and the services defined in the main Compose file may use other targets to build or directly reference other images.
Learn how to distribute your dev environment