ref(docker): Use docker buildx (BuildKit) to publish docker images

README.md

@@ -904,17 +904,16 @@ targets:
 
 ### Docker (`docker`)
 
-Pulls an existing source image tagged with the revision SHA, and then pushed it
-to a new target tagged with the released version. No release
-assets are required for this target except for the source image at the provided
-source image location so it would be a good idea to add a status check that
-ensures the source image exists, otherwise `craft publish` will fail at the
-`docker pull` step, causing an interrupted publish. This is an issue for other,
-non-idempotent targets, not for the Docker target.
+Copies an existing source image tagged with the revision SHA to a new target
+tagged with the released version. No release assets are required for this target
+except for the source image at the provided source image location so it would be
+a good idea to add a status check that ensures the source image exists, otherwise
+`craft publish` will fail at the copy step, causing an interrupted publish.
+This is an issue for other, non-idempotent targets, not for the Docker target.
 
 **Environment**
 
-`docker` executable (or something equivalent) must be installed on the system.
+`docker` executable (or something equivalent) with BuildKit must be installed on the system.
 
 | Name              | Description                                |
 | ----------------- | ------------------------------------------ |

src/targets/docker.ts

@@ -83,29 +83,14 @@ export class DockerTarget extends BaseTarget {
   }
 
   /**
-   * Pushes the the source image into local
-   * @param revision Image tag, usually the git revision
-   */
-  public async pull(revision: string): Promise<any> {
-    this.logger.debug('Pulling source image...');
-    const sourceImage = renderTemplateSafe(this.dockerConfig.sourceTemplate, {
-      ...this.dockerConfig,
-      revision,
-    });
-    return spawnProcess(
-      DOCKER_BIN,
-      ['pull', sourceImage],
-      {},
-      { enableInDryRunMode: true }
-    );
-  }
-
-  /**
-   * Pushes the locally tagged source image to Docker Hub
+   * Copies an existing local or remote docker image to a new destination.
+   *
+   * Requires BuildKit / `docker buildx` to be installed.
+   *
    * @param sourceRevision The tag/revision for the source image
    * @param version The release version for the target image
    */
-  public async push(sourceRevision: string, version: string): Promise<any> {
+  async copy(sourceRevision: string, version: string): Promise<any> {
     const sourceImage = renderTemplateSafe(this.dockerConfig.sourceTemplate, {
       ...this.dockerConfig,
       revision: sourceRevision,
@@ -114,11 +99,11 @@ export class DockerTarget extends BaseTarget {
       ...this.dockerConfig,
       version,
     });
-    this.logger.debug('Tagging target image...');
-    await spawnProcess(DOCKER_BIN, ['tag', sourceImage, targetImage]);
+
+    this.logger.debug(`Copying image from ${sourceImage} to ${targetImage}...`);
     return spawnProcess(
       DOCKER_BIN,
-      ['push', targetImage],
+      ['buildx', 'imagetools', 'create', '--tag', targetImage, sourceImage],
       {},
       { showStdout: true }
     );
@@ -132,8 +117,7 @@ export class DockerTarget extends BaseTarget {
    */
   public async publish(version: string, revision: string): Promise<any> {
     await this.login();
-    await this.pull(revision);
-    await this.push(revision, version);
+    await this.copy(revision, version);
 
     this.logger.info('Docker release complete');
   }