Cirrus: Use google mirror for docker.io

Signed-off-by: Chris Evich <cevich@redhat.com>

contrib/cirrus/lib.sh

@@ -208,6 +208,7 @@ install_test_configs() {
     # as the default).  This config prevents allocation of network address space used
     # by default in google cloud.  https://cloud.google.com/vpc/docs/vpc#ip-ranges
     install -v -D -m 644 $SCRIPT_BASE/99-do-not-use-google-subnets.conflist /etc/cni/net.d/
+
     install -v -D -m 644 ./test/registries.conf /etc/containers/
 }
 

contrib/cirrus/setup_environment.sh

@@ -178,6 +178,8 @@ case "$TEST_FLAVOR" in
             remove_packaged_podman_files
             make install PREFIX=/usr ETCDIR=/etc
         fi
+
+        install_test_configs
         ;;
     vendor) make clean ;;
     release) ;;

test/registries.conf

@@ -1,10 +1,17 @@
 # Note that changing the order here may break tests.
-[registries.search]
-registries = ['docker.io', 'quay.io', 'registry.fedoraproject.org']
+unqualified-search-registries = ['docker.io', 'quay.io', 'registry.fedoraproject.org']
 
-[registries.insecure]
-registries = []
+[[registry]]
+# In Nov. 2020, Docker rate-limits image pulling.  To avoid hitting these
+# limits while testing, always use the google mirror for qualified and
+# unqualified `docker.io` images.
+# Ref: https://cloud.google.com/container-registry/docs/pulling-cached-images
+prefix="docker.io"
+location="mirror.gcr.io"
 
-#blocked (docker only)
-[registries.block]
-registries = []
+# 2020-10-27 a number of images are not present in gcr.io, and podman
+# barfs spectacularly when trying to fetch them. We've hand-copied
+# those to quay, using skopeo copy --all ...
+[[registry]]
+prefix="docker.io/library"
+location="quay.io/libpod"