feat(build): add image and cloudbuild configs for pre-commit (#4898)

* feat(build): add image and cloudbuild configs for pre-commit

* fix(build): clean up lint shellcheck

* chore: only fetch primary branch from origin

kythe/release/cloudbuild/lint.yaml

@@ -0,0 +1,18 @@
+steps:
+  - name: gcr.io/cloud-builders/git
+    args:
+      - fetch
+      - '--unshallow'
+      - '--no-tags'
+      - origin
+      - master
+  - name: gcr.io/kythe-repo/pre-commit
+    args:
+      - run
+      - '--hook-stage'
+      - commit
+      - '--show-diff-on-failure'
+      - '--from-ref'
+      - origin/master
+      - '--to-ref'
+      - HEAD

kythe/release/cloudbuild/pre-commit/Dockerfile

@@ -0,0 +1,53 @@
+# Copyright 2020 The Kythe Authors. All rights reserved.
+#
+# 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.
+
+# docker build -t gcr.io/kythe-repo/pre-commit .
+FROM ubuntu:focal
+
+RUN apt-get update \
+        && apt-get upgrade -y \
+        && apt-get install -y --no-install-recommends \
+                curl ca-certificates \
+                # pre-commit dependencies
+                python3 python3-dev python3-pip \
+                # Linter dependencies
+                golang-go shellcheck clang-format-11 openjdk-11-jre-headless git \
+        && apt-get clean \
+        && rm -rf /var/lib/apt/lists/*
+
+# Make clang-format-11 the default
+RUN update-alternatives \
+      --install /usr/bin/clang-format clang-format /usr/bin/clang-format-11    100
+
+# Install pip-packages
+RUN pip3 install --upgrade pip \
+ && pip3 install pre-commit
+
+# Install extra linters
+RUN go get github.com/bazelbuild/buildtools/buildifier \
+ && go get golang.org/x/lint/golint \
+ && go get honnef.co/go/tools/cmd/staticcheck
+
+# Fetch the latest version of google-java-format from GitHub
+RUN curl -s https://api.github.com/repos/google/google-java-format/releases/latest \
+        | sed -n '/browser_download_url/s/[^:]*:[^"]*\("[^"]*"\).*/url = \1/p' \
+        | egrep 'google-java-format-[^-]*-all-deps.jar' \
+        | curl -L -o /usr/bin/google-java-format.jar -K - \
+        && /bin/echo -e '#!/bin/sh\nexec java -jar /usr/bin/google-java-format.jar "$@"' >/usr/bin/google-java-format \
+        && chmod +x /usr/bin/google-java-format
+
+# Install go wrapper script
+ADD go /usr/local/bin/go
+ENV PATH=$PATH:/root/go/bin
+ENTRYPOINT ["pre-commit"]

kythe/release/cloudbuild/pre-commit/cloudbuild.yaml

@@ -0,0 +1,12 @@
+steps:
+- name: 'gcr.io/cloud-builders/docker'
+  entrypoint: 'bash'
+  args: ['-c', 'docker pull gcr.io/$PROJECT_ID/pre-commit:latest || exit 0']
+- name: 'gcr.io/cloud-builders/docker'
+  args: [
+            'build',
+            '-t', 'gcr.io/$PROJECT_ID/pre-commit:latest',
+            '--cache-from', 'gcr.io/$PROJECT_ID/pre-commit:latest',
+            '.'
+        ]
+images: ['gcr.io/$PROJECT_ID/pre-commit:latest']

kythe/release/cloudbuild/pre-commit/go

@@ -0,0 +1,72 @@
+#!/bin/bash -e
+#
+# Copyright 2019 The Kythe Authors. All rights reserved.
+#
+# 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.
+#
+# Wrapper script to run the Go version specified by a go.mod file.
+
+CACHE="$HOME/.cache/goversions"
+
+GO="$(command -v go | xargs -L1 realpath | grep -v "$(realpath "$0")" | head -n1)"
+if ! [[ -x "$GO" ]]; then
+  echo "ERROR: failed to find ambient go tool" >&2
+  exit 1
+fi
+
+find_gomod() {
+  local dir="$PWD"
+  local f="$dir/go.mod"
+  while true; do
+    if [[ -r "$f" ]]; then
+      echo "$f"
+      return
+    elif [[ "/" == "$dir" ]]; then
+      return 1
+    fi
+    dir="$(dirname "$dir")"
+  done
+}
+
+if ! gomod="$(find_gomod)"; then
+  echo "WARNING: could not find go.mod" >&2
+  exec "$GO" "$@"
+fi
+
+if ! version="$(grep -Po '(?<=^go\s)\d+(\.\d+)+$' "$gomod")"; then
+  echo "WARNING: could not find version in go.mod" >&2
+  exec "$GO" "$@"
+fi
+
+GOROOT="${CACHE}/${version}/go"
+
+if [[ -x "$GOROOT/bin/go" ]]; then
+  # Cache hit: exec go tool
+  exec "$GOROOT/bin/go" "$@"
+fi
+
+# Setup temporary location for archive
+archive="$(mktemp)"
+trap "rm '$archive'" EXIT ERR INT
+
+# Download and extract Go compiler
+url="https://dl.google.com/go/go${version}.linux-amd64.tar.gz"
+curl -L "$url">"$archive"
+dir="$(dirname "$GOROOT")"
+rm -rf "$dir"
+mkdir -p "$dir"
+tar xf "$archive" -C "$dir"
+rm -f "$archive"
+
+# Run go tool
+exec "$GOROOT/bin/go" "$@"