ci.sh/GHA: Add docker-build-push step/action

A major maintainability issue for years has been that the CI assumes
that a docker image for the implementation exists in Docker's registry
(named kanaka/mal-test-IMPL). This means the upstream maintainers have
to be involved in the PR loop to build the implementation Dockerfile,
push to the docker registry and then have the PR submitter re-run CI.

To address this, in ci.sh, the docker-build-push action will try to pull
the image and then continue as normal. If the pull fails then it will
build the image and push it (if the build is running in the context of
the upstream repo's main branch) and then continue.

Also, this switches to using ghcr.io as the default repo for images
which will make image transfer more local (during CI) and hopefully
a fair bit faster (and avoid potential docker pull limits).

Add a steps to the GHA main workflow that do a docker login to ghcr.io
and then call `ci.sh docker-build-push ${IMPL}`.

.github/workflows/main.yml

@@ -40,6 +40,16 @@ jobs:
       - uses: actions/checkout@v2
         with:
           fetch-depth: 0  # Need full history for voom like versions
+      - name: Log in to GitHub Container Registry
+        uses: docker/login-action@v2
+        with:
+          registry: ghcr.io
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+      - name: Docker Build/Push
+        run: |
+          export ${{ matrix.IMPL }}
+          ./ci.sh docker-build-push ${IMPL}
       - name: Build
         run: |
           export ${{ matrix.IMPL }}

Makefile

@@ -126,7 +126,7 @@ STEP_TEST_FILES = $(strip $(wildcard \
 
 # DOCKERIZE utility functions
 lc = $(subst A,a,$(subst B,b,$(subst C,c,$(subst D,d,$(subst E,e,$(subst F,f,$(subst G,g,$(subst H,h,$(subst I,i,$(subst J,j,$(subst K,k,$(subst L,l,$(subst M,m,$(subst N,n,$(subst O,o,$(subst P,p,$(subst Q,q,$(subst R,r,$(subst S,s,$(subst T,t,$(subst U,u,$(subst V,v,$(subst W,w,$(subst X,x,$(subst Y,y,$(subst Z,z,$1))))))))))))))))))))))))))
-impl_to_image = kanaka/mal-test-$(call lc,$(1)):$(shell ./voom-like-version.sh impls/$(1)/Dockerfile)
+impl_to_image = ghcr.io/kanaka/mal-test-$(call lc,$(1)):$(shell ./voom-like-version.sh impls/$(1)/Dockerfile)
 
 actual_impl = $(if $(filter mal,$(1)),$(patsubst %-mal,%,$(MAL_IMPL)),$(1))
 

ci.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 
 set -ex
 
@@ -24,11 +24,23 @@ mode_var=${raw_mode_var/-/__}
 mode_var=${mode_var/./__}
 mode_val=${!mode_var}
 
-MAKE="make ${mode_val:+${mode_var}=${mode_val}}"
-
 log_prefix="${ACTION}${REGRESS:+-regress}-${IMPL}${mode_val:+-${mode_val}}${MAL_IMPL:+-${MAL_IMPL}}"
 TEST_OPTS="${TEST_OPTS} --debug-file ../../${log_prefix}.debug"
 
+img_base="${MAL_IMPL:-${IMPL}}"
+img_impl="${img_base%%-mal}"
+img_name="mal-test-${img_impl,,}"
+img_ver=$(./voom-like-version.sh impls/${img_impl}/Dockerfile)
+IMAGE="ghcr.io/kanaka/${img_name}:${img_ver}"
+
+# If NO_DOCKER is blank then run make in a docker image
+MAKE="make ${mode_val:+${mode_var}=${mode_val}}"
+if [ -z "${NO_DOCKER}" ]; then
+    # We could just use make DOCKERIZE=1 instead but that does add
+    # non-trivial startup overhead for each step.
+    MAKE="docker run -i -u $(id -u) -v `pwd`:/mal ${IMAGE} ${MAKE}"
+fi
+
 # Log everything below this point:
 exec &> >(tee ./${log_prefix}.log)
 
@@ -47,18 +59,18 @@ echo "IMPL: ${IMPL}"
 echo "BUILD_IMPL: ${BUILD_IMPL}"
 echo "MAL_IMPL: ${MAL_IMPL}"
 echo "TEST_OPTS: ${TEST_OPTS}"
-
-# If NO_DOCKER is blank then launch use a docker image, otherwise use
-# the Travis/Github Actions image/tools directly.
-if [ -z "${NO_DOCKER}" ]; then
-    img_impl=$(echo "${MAL_IMPL:-${IMPL}}" | tr '[:upper:]' '[:lower:]')
-    img_ver=$(./voom-like-version.sh impls/${img_impl}/Dockerfile)
-    # We could just use make DOCKERIZE=1 instead but that does add
-    # non-trivial startup overhead for each step.
-    MAKE="docker run -i -u $(id -u) -v `pwd`:/mal kanaka/mal-test-${img_impl%%-mal}:${img_ver} ${MAKE}"
-fi
+echo "IMAGE: ${IMAGE}"
+echo "MAKE: ${MAKE}"
 
 case "${ACTION}" in
+docker-build-push)
+    if ! docker pull ${IMAGE}; then
+        make "docker-build^${MAL_IMPL:-${IMPL}}"
+        if [ "${GITHUB_REF}" = "refs/heads/main" ]; then
+            docker push ${IMAGE}
+        fi
+    fi
+    ;;
 build)
     # rpython often fails on step9 in compute_vars_longevity
     # so build step9, then continue with the full build