module_map.rb

#!/usr/bin/env ruby

# Copyright 2019 Google
#
# 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.

# Generate a module map file from a podspec.

# CocoaPods generated module maps are not appropriate because CocoaPods uses
# xcconfig files to specify framework and library dependencies.

# This script is currently intended for Zipfile building only for iOS.
# If multi-platform support is required in the future, the consumer parameter
# could be added to the command line.

require'cocoapods'

# Enable ruby options after 'require' because cocoapods is noisy
$VERBOSE =true# ruby -w
#$DEBUG = true # ruby --debug

defusage()
script=File.basename($0)
STDERR.puts<<~EOF
 USAGE: #{script} podspec output_file

 podspec is the podspec to generate the module map for.
 output_file is the file to write the modulemap.
 EOF
end

defmain(args)
ifargs.size < 2then
usage()
exit(1)
end

podspec_file=args[0]

trace('loading',podspec_file)
spec=Pod::Spec.from_file(podspec_file)
consumer=spec.consumer("ios")

trace('generating module map for ',spec.module_name,)
contents=generate(spec.module_name,consumer.frameworks,consumer.libraries)
File.open(args[1],'w'){ |file| file.write(contents)}
end

# Generates the contents of the module.modulemap file.
#
# @return [String]
#
defgenerate(name,frameworks,libraries)
<<~MODULE_MAP
 framework module #{name} {
 umbrella header "#{name}.h"
 export *
 module * { export * }
#{frameworks.map{|framework| "link framework \"#{framework}\""}.join("\n ")}
#{libraries.map{|library| "link \"#{library}\""}.join("\n ")}
 }
 MODULE_MAP
end


deftrace(*args)
returnif not $DEBUG

STDERR.puts(args.join(' '))
end

main(ARGV)