Develop with Docker Engine API

Docker provides an API for interacting with the Docker daemon (called the Docker Engine API), as well as SDKs for Go and Python. The SDKs allow you to build and scale Docker apps and solutions quickly and easily. If Go or Python don’t work for you, you can use the Docker Engine API directly.

For information about Docker Engine SDKs, see Develop with Docker Engine SDKs.

The Docker Engine API is a RESTful API accessed by an HTTP client such as wget or curl, or the HTTP library which is part of most modern programming languages.

View the API reference

You can view the reference for the latest version of the API or choose a specific version.

Versioned API and SDK

The version of the Docker Engine API you should use depends upon the version of your Docker daemon and Docker client.

A given version of the Docker Engine SDK supports a specific version of the Docker Engine API, as well as all earlier versions. If breaking changes occur, they are documented prominently.

Daemon and client API mismatches

The Docker daemon and client do not necessarily need to be the same version at all times. However, keep the following in mind.

• If the daemon is newer than the client, the client does not know about new features or deprecated API endpoints in the daemon.

• If the client is newer than the daemon, the client can request API endpoints that the daemon does not know about.

A new version of the API is released when new features are added. The Docker API is backward-compatible, so you do not need to update code that uses the API unless you need to take advantage of new features.

To see the highest version of the API your Docker daemon and client support, use docker version:

$ docker version

Client:
  Version:           19.03.5
  API version:       1.40
  Go version:        go1.12.12
  Git commit:        633a0ea
  Built:             Wed Nov 13 07:22:37 2019
  OS/Arch:           windows/amd64
  Experimental:      true


Server:
  Version:          19.03.5
  API version:      1.40 (minimum version 1.12)
  Go version:       go1.12.12
  Git commit:       633a0ea
  Built:            Wed Nov 13 07:29:19 2019
  OS/Arch:          linux/amd64
  ...

You can specify the API version to use, in one of the following ways:

• When using the SDK, use the latest version you can, but at least the version that incorporates the API version with the features you need.

• When using curl directly, specify the version as the first part of the URL. For instance, if the endpoint is /containers/, you can use /v1.40/containers/.

• To force the Docker CLI or the Docker Engine SDKs to use an old version version of the API than the version reported by docker version, set the environment variable DOCKER_API_VERSION to the correct version. This works on Linux, Windows, or macOS clients.

  DOCKER_API_VERSION='1.40'
  

  While the environment variable is set, that version of the API is used, even if the Docker daemon supports a newer version. This environment variable disables API version negotiation, and as such should only be used if you must use a specific version of the API, or for debugging purposes.

• The Docker Go SDK allows you to enable API version negotiation, automatically selects an API version that is supported by both the client, and the Docker Engine that is used.

• For the SDKs, you can also specify the API version programmatically, as a parameter to the client object. See the Go constructor or the Python SDK documentation for client.

API version matrix