github.com/munnerz/test-infra@v0.0.0-20190108210205-ce3d181dc989/images/bootstrap/runner.sh

#!/usr/bin/env bash
# Copyright 2018 The Kubernetes Authors.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

# generic runner script, handles DIND, bazelrc for caching, etc.

# Check if the job has opted-in to bazel remote caching and if so generate 
# .bazelrc entries pointing to the remote cache
export BAZEL_REMOTE_CACHE_ENABLED=${BAZEL_REMOTE_CACHE_ENABLED:-false}
if [[ "${BAZEL_REMOTE_CACHE_ENABLED}" == "true" ]]; then
    echo "Bazel remote cache is enabled, generating .bazelrcs ..."
    # if we have a test-infra checkout (because bootstrap), use that since
    # it is newer and this is probably k/k so we can push fixes faster this way
    # otherwise run the one baked into the image
    # TODO(bentheelder): someday only support the pod-utils
    if [[ -d "./test-infra" ]]; then
        ./test-infra/images/bootstrap/create_bazel_cache_rcs.sh
    else
        /usr/local/bin/create_bazel_cache_rcs.sh
    fi
fi


# used by cleanup_dind to ensure binfmt_misc entries are not persisted
# TODO(bentheelder): consider moving *all* cleanup into a more robust program
cleanup_binfmt_misc() {
    # make sure the vfs is mounted
    # TODO(bentheelder): if this logic is moved out and made more general
    # we need to check that the host actually has binfmt_misc support first.
    if [ ! -f /proc/sys/fs/binfmt_misc/status ]; then
        mount binfmt_misc -t binfmt_misc /proc/sys/fs/binfmt_misc
    fi
    # https://www.kernel.org/doc/html/v4.13/admin-guide/binfmt-misc.html
    # You can remove one entry or all entries by echoing -1 
    # to /proc/.../the_name or /proc/sys/fs/binfmt_misc/status.
    echo -1 >/proc/sys/fs/binfmt_misc/status
    # list entries
    ls -al /proc/sys/fs/binfmt_misc
}

# runs custom docker data root cleanup binary and debugs remaining resources
cleanup_dind() {
    barnacle || true
    # list what images and volumes remain
    echo "Remaining docker images and volumes are:"
    docker images --all || true
    docker volume ls || true
    # cleanup binfmt_misc
    echo "Cleaning up binfmt_misc ..."
    # note: we run this in a subshell so we can trace it for now
    (set -x; cleanup_binfmt_misc || true)
}

# Check if the job has opted-in to docker-in-docker availability.
export DOCKER_IN_DOCKER_ENABLED=${DOCKER_IN_DOCKER_ENABLED:-false}
if [[ "${DOCKER_IN_DOCKER_ENABLED}" == "true" ]]; then
    echo "Docker in Docker enabled, initializing..."
    printf '=%.0s' {1..80}; echo
    # If we have opted in to docker in docker, start the docker daemon,
    service docker start
    # the service can be started but the docker socket not ready, wait for ready
    WAIT_N=0
    MAX_WAIT=5
    while true; do
        # docker ps -q should only work if the daemon is ready
        docker ps -q > /dev/null 2>&1 && break
        if [[ ${WAIT_N} -lt ${MAX_WAIT} ]]; then
            WAIT_N=$((WAIT_N+1))
            echo "Waiting for docker to be ready, sleeping for ${WAIT_N} seconds."
            sleep ${WAIT_N}
        else
            echo "Reached maximum attempts, not waiting any longer..."
            break
        fi
    done
    cleanup_dind
    printf '=%.0s' {1..80}; echo
    echo "Done setting up docker in docker."
fi

# disable error exit so we can run post-command cleanup
set +o errexit

# add $GOPATH/bin to $PATH
export PATH=$GOPATH/bin:$PATH
# Authenticate gcloud, allow failures
if [[ -n "${GOOGLE_APPLICATION_CREDENTIALS:-}" ]]; then
  gcloud auth activate-service-account --key-file="${GOOGLE_APPLICATION_CREDENTIALS}" || true
fi

# Use a reproducible build date based on the most recent git commit timestamp.
export SOURCE_DATE_EPOCH=$(git log -1 --pretty=%ct || true)

# actually start bootstrap and the job
"$@"
EXIT_VALUE=$?

# cleanup after job
if [[ "${DOCKER_IN_DOCKER_ENABLED}" == "true" ]]; then
    echo "Cleaning up after docker in docker."
    printf '=%.0s' {1..80}; echo
    cleanup_dind
    printf '=%.0s' {1..80}; echo
    echo "Done cleaning up after docker in docker."
fi

# preserve exit value from job / bootstrap
exit ${EXIT_VALUE}