ProtoCompiler podspec

Still needed:

- Make it build protoc if it’s not in the root (i.e. if we're developing locally)
- Put the gRPC plugin in the GitHub release page, and add a podspec for it that does the same

src/objective-c/ProtoCompiler.podspec

+# BoringSSL CocoaPods podspec
+
+# Copyright 2015, Google Inc.
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+#     * Redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer.
+#     * Redistributions in binary form must reproduce the above
+# copyright notice, this list of conditions and the following disclaimer
+# in the documentation and/or other materials provided with the
+# distribution.
+#     * Neither the name of Google Inc. nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+Pod::Spec.new do |s|
+  s.name     = 'ProtoCompiler'
+  v = '3.0.0-beta-3.1'
+  s.version  = v
+  s.summary  = 'The Protobuf Compiler (protoc) generates Objective-C files from .proto files'
+  s.description = <<-DESC
+    This podspec only downloads protoc so that local pods generating protos can execute it as part
+    of their prepare_command.
+    The generated code will have a dependency on the Protobuf Objective-C runtime of the same
+    version. The runtime can be obtained as the "Protobuf" pod.
+  DESC
+  s.homepage = 'https://github.com/google/protobuf'
+  s.license  = 'New BSD'
+  # "The name and email addresses of the library maintainers, not the Podspec maintainer."
+  s.authors  = { 'The Protocol Buffers contributors' => 'protobuf@googlegroups.com' }
+
+  s.source = {
+    :http => "https://github.com/google/protobuf/releases/download/v#{v}/protoc-#{v}-osx-fat.zip",
+    # TODO(jcanizales): Add sha1 or sha256
+    # :sha1 => '??',
+  }
+
+  s.preserve_paths = 'protoc',
+                     'google/**/*.proto' # Well-known protobuf types
+end

src/objective-c/tests/Podfile

@@ -17,6 +17,7 @@ GRPC_LOCAL_SRC = '../../..'
 ).each do |target_name|
   target target_name do
     pod 'Protobuf', :path => "#{GRPC_LOCAL_SRC}/third_party/protobuf", :inhibit_warnings => true
+    pod 'ProtoCompiler',  :podspec => "#{GRPC_LOCAL_SRC}/src/objective-c"
     pod 'BoringSSL', :podspec => "#{GRPC_LOCAL_SRC}/src/objective-c", :inhibit_warnings => true
     pod 'CronetFramework', :podspec => "#{GRPC_LOCAL_SRC}/src/objective-c"
     pod 'gRPC', :path => GRPC_LOCAL_SRC

src/objective-c/tests/RemoteTestClient/RemoteTest.podspec

@@ -11,13 +11,18 @@ Pod::Spec.new do |s|
   s.osx.deployment_target = '10.9'
 
   # Run protoc with the Objective-C and gRPC plugins to generate protocol messages and gRPC clients.
+  repo_root = '../../../..'
+  pods_root = "#{repo_root}/src/objective-c/tests/Pods"
+  bin_dir = "#{repo_root}/bins/$CONFIG"
+
+  protoc = "#{pods_root}/ProtoCompiler/protoc" # "#{bin_dir}/protobuf/protoc"
+  plugin = "#{bin_dir}/grpc_objective_c_plugin"
   s.prepare_command = <<-CMD
-    BINDIR=../../../../bins/$CONFIG
-    PROTOC=$BINDIR/protobuf/protoc
-    PLUGIN=$BINDIR/grpc_objective_c_plugin
-    $PROTOC --plugin=protoc-gen-grpc=$PLUGIN --objc_out=. --grpc_out=. *.proto
+    #{protoc} --plugin=protoc-gen-grpc=#{plugin} --objc_out=. --grpc_out=. *.proto
   CMD
 
+  s.dependency "ProtoCompiler", "~> 3.0.0-beta-3.1"
+
   s.subspec "Messages" do |ms|
     ms.source_files = "*.pbobjc.{h,m}"
     ms.header_mappings_dir = "."