gha/e2e: Also test against moby master

Add a "master" engine-version to the e2e matrix to catch regressions
against the upcoming engine release before it reaches an rc.

There is no "master" dind image, so just copy the engine binary from the
moby/moby-bin:master image and put it into the latest dind image.

Signed-off-by: Paweł Gronowski <pawel.gronowski@docker.com>

.github/workflows/e2e.yml

@@ -37,6 +37,7 @@ jobs:
           - alpine
           - debian
         engine-version:
+          - master  # moby/moby-bin:master
           - rc  # latest rc
           - 29  # latest
           - 28  # latest - 1

e2e/compose-env.yaml

@@ -31,6 +31,7 @@ services:
         dockerfile: engine/Dockerfile
         args:
           ENGINE_VERSION: ${ENGINE_VERSION:-29}
+          ENGINE_SOURCE: ${ENGINE_SOURCE:-dind}
       privileged: true
       command: ['--insecure-registry=registry:5000', '--insecure-registry=privateregistry:5001', '--experimental']
       environment:

e2e/testdata/Dockerfile.connhelper-ssh

@@ -3,8 +3,16 @@
 # ENGINE_VERSION is the version of the (docker-in-docker) Docker Engine to
 # test against.
 ARG ENGINE_VERSION=29
+# ENGINE_SOURCE is "dind" or "moby-bin" (moby/moby-bin:master).
+ARG ENGINE_SOURCE=dind
 
-FROM docker:${ENGINE_VERSION}-dind
+FROM docker:${ENGINE_VERSION}-dind AS engine-dind
+
+# moby/moby-bin only has the daemon binaries.
+FROM docker:dind AS engine-moby-bin
+COPY --link --from=moby/moby-bin:master / /usr/local/bin/
+
+FROM engine-${ENGINE_SOURCE}
 
 # the openssh-client update is needed for security reasons when using docker:23.0-dind, currently maintained as an lts by mirantis
 RUN apk --no-cache add openssl openssh-client openssh-server shadow && \

e2e/testdata/engine/Dockerfile

@@ -1,5 +1,14 @@
 ARG ENGINE_VERSION
-FROM docker:${ENGINE_VERSION}-dind
+# ENGINE_SOURCE is "dind" or "moby-bin" (moby/moby-bin:master).
+ARG ENGINE_SOURCE=dind
+
+FROM docker:${ENGINE_VERSION}-dind AS engine-dind
+
+# moby/moby-bin only has the daemon binaries.
+FROM docker:dind AS engine-moby-bin
+COPY --link --from=moby/moby-bin:master / /usr/local/bin/
+
+FROM engine-${ENGINE_SOURCE}
 
 # Trust the tlsregistry CA so dockerd connects without --insecure-registry.
 COPY registry/certs/ca.crt /usr/local/share/ca-certificates/tlsregistry-ca.crt

scripts/test/e2e/run

@@ -42,6 +42,11 @@ setup() {
         sh e2e/testdata/registry/certs/gen-certs.sh
     fi
 
+    # ENGINE_VERSION=master tests against moby/moby-bin:master.
+    if [ "${ENGINE_VERSION:-}" = "master" ]; then
+        export ENGINE_SOURCE=moby-bin
+    fi
+
     COMPOSE_PROJECT_NAME=$project COMPOSE_FILE=$file docker compose up --build -d >&2
 
     # Ensure supporting services exist before running tests. If one fails to start,