Use explicit image paths

To make it clear that docker hub is but one of many possible registries,
update our usage of FROM and image: lines to include docker.io in the
path.

There are a few other FROM lines for the gitea images which are handled
in a separate stack.

Change-Id: I6fafd5f659ad19de6951574afc9a6b6a4cf184df

docker/gerrit/2.13/Dockerfile

@@ -13,7 +13,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-FROM openjdk:8
+FROM docker.io/library/openjdk:8
 
 # It's not 100% clear that unzip and libmysql-java are needed
 RUN apt-get update \

docker/gerrit/base/Dockerfile

@@ -13,12 +13,12 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-FROM opendevorg/python-builder as builder
+FROM docker.io/opendevorg/python-builder as builder
 
 COPY . /tmp/src
 RUN assemble
 
-FROM openjdk:8
+FROM docker.io/library/openjdk:8
 
 RUN apt-get update \
   && apt-get install -y dumb-init python3-launchpadlib \

docker/gerrit/bazel/Dockerfile

@@ -13,7 +13,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-FROM opendevorg/bazel as builder
+FROM docker.io/opendevorg/bazel as builder
 
 USER builder
 COPY . /usr/src
@@ -21,6 +21,6 @@ COPY . /usr/src
 ARG BAZEL_OPTS
 RUN cd /usr/src && bash build-gerrit.sh
 
-FROM opendevorg/gerrit-base
+FROM docker.io/opendevorg/gerrit-base
 
 COPY --from=builder /usr/src/bazel-bin/release.war /var/gerrit/bin/gerrit.war

docker/python-base/Dockerfile

@@ -13,7 +13,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-FROM python:3.7-slim
+FROM docker.io/library/python:3.7-slim
 
 RUN apt-get update \
   && apt-get install -y dumb-init libjemalloc2 \

docker/python-builder/Dockerfile

@@ -13,8 +13,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-
-FROM python:3.7-slim as fake-python
+FROM docker.io/library/python:3.7-slim as fake-python
 
 WORKDIR /tmp
 RUN apt-get update \
@@ -23,7 +22,7 @@ RUN apt-get update \
 COPY python3-dev.control /tmp/python3-dev.control
 RUN equivs-build /tmp/python3-dev.control
 
-FROM python:3.7-slim
+FROM docker.io/library/python:3.7-slim
 
 COPY --from=fake-python /tmp/python3-dev_4.0.0_all.deb /tmp/python3-dev_4.0.0_all.deb
 COPY scripts/assemble /usr/local/bin/assemble

playbooks/roles/gitea/templates/docker-compose.yaml.j2

@@ -4,7 +4,7 @@ version: '2'
 
 services:
   mariadb:
-    image: mariadb:10.4
+    image: docker.io/library/mariadb:10.4
     network_mode: host
     restart: always
     environment:
@@ -17,7 +17,7 @@ services:
   gitea-web:
     depends_on:
       - mariadb
-    image: opendevorg/gitea:latest
+    image: docker.io/opendevorg/gitea:latest
     network_mode: host
     restart: always
     environment:
@@ -37,7 +37,7 @@ services:
       - mariadb
     environment:
       - SSH_LISTEN_PORT=222
-    image: opendevorg/gitea-openssh
+    image: docker.io/opendevorg/gitea-openssh
     network_mode: host
     restart: always
     volumes:

playbooks/roles/haproxy/files/docker/docker-compose.yaml

@@ -5,7 +5,7 @@ version: '2'
 services:
   haproxy:
     restart: always
-    image: haproxy:latest
+    image: docker.io/library/haproxy:latest
     network_mode: host
     volumes:
       - /dev/log:/dev/log
@@ -13,7 +13,7 @@ services:
       - /var/haproxy/run:/var/haproxy/run
   haproxy-statsd:
     restart: always
-    image: opendevorg/haproxy-statsd:latest
+    image: docker.io/opendevorg/haproxy-statsd:latest
     network_mode: host
     volumes:
       - /var/haproxy/run:/var/haproxy/run

playbooks/roles/registry/files/registry-docker/docker-compose.yaml

@@ -5,7 +5,7 @@ version: '2'
 services:
   registry:
     restart: always
-    image: zuul/zuul-registry
+    image: docker.io/zuul/zuul-registry
     network_mode: host
     volumes:
       - /var/registry/certs:/certs

playbooks/roles/zuul-preview/files/zuul-preview-docker/docker-compose.yaml

@@ -5,7 +5,7 @@ version: '2'
 services:
   zuul-preview:
     restart: always
-    image: zuul/zuul-preview:latest
+    image: docker.io/zuul/zuul-preview:latest
     network_mode: host
     environment:
       ZUUL_API_URL: https://zuul.opendev.org/