grpc-swift/scripts/license-check.sh

#!/bin/bash

# Copyright 2019, gRPC 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.

# This script checks the copyright headers in source *.swift source files and
# exits if they do not match the expected header. The year, or year range in
# headers is replaced with 'YEARS' for comparison.

# Copyright header text and SHA for *.swift files
read -r -d '' COPYRIGHT_HEADER_SWIFT << 'EOF'
/*
 * Copyright YEARS, gRPC 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.
 */
EOF
SWIFT_SHA=$(echo "$COPYRIGHT_HEADER_SWIFT" | shasum | awk '{print $1}')

# Copyright header text and SHA for *.grpc.swift files
read -r -d '' COPYRIGHT_HEADER_SWIFT_GRPC << 'EOF'
// Copyright YEARS, gRPC 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.
EOF
SWIFT_GRPC_SHA=$(echo "$COPYRIGHT_HEADER_SWIFT_GRPC" | shasum | awk '{print $1}')

# Copyright header text and SHA for *.pb.swift files
read -r -d '' COPYRIGHT_HEADER_SWIFT_PB << 'EOF'
// Copyright YEARS gRPC 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.
EOF
SWIFT_GRPC_PB=$(echo "$COPYRIGHT_HEADER_SWIFT_PB" | shasum | awk '{print $1}')

replace_years() {
  sed -e 's/201[56789]-20[12][0-9]/YEARS/' -e 's/201[56789]/YEARS/'
}

# Checks the Copyright headers for *.swift files in this repository against the
# expected headers.
#
# Prints the names of all files with invalid or missing headers and exits with
# a non-zero status code.
check_copyright_headers() {
  # Exceptions:
  # - echo.pb.swift: Google is the author of the corresponding .proto, so the
  #   generated header has Google as the author.
  # - LinuxMain.swift, XCTestManifests.swift: Both of these files are generated
  #   by SwiftPM and do not have headers.
  find . -name '*.swift' \
    ! -name 'echo.pb.swift' \
    ! -name 'LinuxMain.swift' \
    ! -name 'XCTestManifests.swift' \
    ! -path './.build/*' \
    | while read -r filename; do
  case $filename in
    # The .grpc.swift and .pb.swift files have additional generated headers with
    # warnings that they have been generated and should not be edited.
    # Package.swift is preceeded by a "swift-tools-version" line.
    *.grpc.swift)
      expected_sha="$SWIFT_GRPC_SHA"
      drop_first=8
      expected_lines=13
      ;;
    *.pb.swift)
      expected_sha="$SWIFT_GRPC_PB"
      drop_first=8
      expected_lines=13
      ;;
    */Package.swift)
      expected_sha="$SWIFT_SHA"
      drop_first=1
      expected_lines=15
      ;;
    *)
      expected_sha="$SWIFT_SHA"
      drop_first=0
      expected_lines=15
      ;;
  esac

  actual_sha=$(head -n "$((drop_first + expected_lines))" "$filename" \
    | tail -n "$expected_lines" \
    | sed -e 's/201[56789]-20[12][0-9]/YEARS/' -e 's/201[56789]/YEARS/' \
    | shasum \
    | awk '{print $1}')

  if [ "$actual_sha" != "$expected_sha" ]; then
    printf "\033[0;31mMissing or invalid copyright headers in '$filename'\033[0m\n"
    exit 1
  fi
  done
}

check_copyright_headers