Separate Core, ProtoRuntime, and RxLibrary subspecs
diff --git a/templates/gRPC-Core.podspec.template b/templates/gRPC-Core.podspec.template
new file mode 100644
index 0000000..ebc23e1
--- /dev/null
+++ b/templates/gRPC-Core.podspec.template
@@ -0,0 +1,100 @@
+%YAML 1.2
+--- |
+  # GRPC CocoaPods podspec
+  # This file has been automatically generated from a template file.
+  # Please look at the templates directory instead.
+  # This file can be regenerated from the template by running
+  # tools/buildgen/generate_projects.sh
+
+  # 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.
+
+  <%!
+  def grpc_files(libs):
+    out = []
+    for lib in libs:
+      if lib.name in ("grpc", "gpr"):
+        out += lib.get('headers', [])
+        out += lib.get('public_headers', [])
+        out += lib.get('src', [])
+    return out;
+  
+  def grpc_private_headers(libs):
+    out = []
+    for lib in libs:
+      if lib.name in ("grpc", "gpr"):
+        out += lib.get('headers', [])
+    return out
+  %>
+  Pod::Spec.new do |s|
+    s.name     = 'gRPC-Core'
+    version = '0.14.0'
+    s.version  = version
+    s.summary  = 'Core cross-platform gRPC library, written in C'
+    s.homepage = 'http://www.grpc.io'
+    s.license  = 'New BSD'
+    s.authors  = { 'The gRPC contributors' => 'grpc-packages@google.com' }
+
+    s.source = {
+      :git => 'https://github.com/grpc/grpc.git',
+      :tag => "release-#{version.gsub(/\./, '_')}-objectivec-#{version}",
+    }
+
+    s.ios.deployment_target = '7.1'
+    s.osx.deployment_target = '10.9'
+    s.requires_arc = false
+
+    name = 'grpc'
+    s.module_name = name
+    s.header_dir = name
+
+    s.source_files = ${(',\n' + 19*' ').join('\'%s\'' % f for f in grpc_files(libs))}
+
+    s.private_header_files = ${(',\n' + 27*' ').join('\'%s\'' % f for f in grpc_private_headers(libs))}
+
+    s.header_mappings_dir = 'include/grpc'
+
+    src_root = '$(PODS_ROOT)/gRPC-Core'
+    # This isn't officially supported in Cocoapods. We've asked for an alternative:
+    # https://github.com/CocoaPods/CocoaPods/issues/4386
+    public_build_settings = {
+      'GRPC_SRC_ROOT' => src_root,
+      'HEADER_SEARCH_PATHS' => '"$(inherited)" "$(GRPC_SRC_ROOT)/include"',
+    }
+    private_build_settings = public_build_settings.merge({
+      'USE_HEADERMAP' => 'NO',
+      'ALWAYS_SEARCH_USER_PATHS' => 'NO',
+      'USER_HEADER_SEARCH_PATHS' => '"$(GRPC_SRC_ROOT)"',
+    })
+    s.user_target_xcconfig = public_build_settings
+    s.pod_target_xcconfig = private_build_settings
+
+    s.libraries = 'z'
+    s.dependency 'BoringSSL', '~> 3.0'
+  end