Update CocoaPods to alpha.20 (#982)

Motivation:

We tagged 1.0.0-alpha.20, let's update the in-repo podspecs too.

Modifications:

- Add an option to build_podspecs.py to start from a given Podspec, this
  is useful when an upload fails.
- Update docs to use latest version in a couple of places.
- Update pods to alpha.20

Result:

Our docs are more up to date.

CGRPCZlib.podspec

@@ -2,7 +2,7 @@ Pod::Spec.new do |s|
 
     s.name = 'CGRPCZlib'
     s.module_name = 'CGRPCZlib'
-    s.version = '1.0.0-alpha.19'
+    s.version = '1.0.0-alpha.20'
     s.license = { :type => 'Apache 2.0', :file => 'LICENSE' }
     s.summary = 'Compression library that provides in-memory compression and decompression functions'
     s.homepage = 'https://www.grpc.io'

Examples/Google/SpeechToText/Podfile

@@ -6,5 +6,5 @@ target 'SpeechToText-gRPC-iOS' do
   use_frameworks!
 
   pod 'SnapKit'
-  pod 'gRPC-Swift', '1.0.0-alpha.19'
+  pod 'gRPC-Swift', '1.0.0-alpha.20'
 end

README.md

@@ -51,7 +51,7 @@ necessary targets:
 
 ```swift
 dependencies: [
-  .package(url: "https://github.com/grpc/grpc-swift.git", from: "1.0.0-alpha.19")
+  .package(url: "https://github.com/grpc/grpc-swift.git", from: "1.0.0-alpha.20")
 ]
 ```
 
@@ -96,7 +96,7 @@ gRPC Swift is currently available [from CocoaPods][pod-new]. To integrate, add
 the following line to your `Podfile`:
 
 ```ruby
-    pod 'gRPC-Swift', '~> 1.0.0-alpha.19'
+    pod 'gRPC-Swift', '~> 1.0.0-alpha.20'
 ```
 
 Then, run `pod install` from command line and use your project's generated

docs/basic-tutorial.md

@@ -39,7 +39,7 @@ To download the example, clone the latest release in `grpc-swift` repository by
 running the following command:
 
 ```sh
-$ git clone -b 1.0.0-alpha.9 https://github.com/grpc/grpc-swift
+$ git clone -b 1.0.0-alpha.20 https://github.com/grpc/grpc-swift
 ```
 
 Then change your current directory to `grpc-swift/Sources/Examples/RouteGuide`:

docs/quick-start.md

@@ -28,7 +28,7 @@ and other tutorials):
 
 ```sh
 $ # Clone the repository at the latest release to get the example code:
-$ git clone -b 1.0.0-alpha.9 https://github.com/grpc/grpc-swift
+$ git clone -b 1.0.0-alpha.20 https://github.com/grpc/grpc-swift
 $ # Navigate to the repository
 $ cd grpc-swift/
 ```

gRPC-Swift-Plugins.podspec

@@ -1,7 +1,7 @@
 Pod::Spec.new do |s|
 
     s.name = 'gRPC-Swift-Plugins'
-    s.version = '1.0.0-alpha.19'
+    s.version = '1.0.0-alpha.20'
     s.license = { :type => 'Apache 2.0', :file => 'LICENSE' }
     s.summary = 'Swift gRPC code generator plugin binaries'
     s.homepage = 'https://www.grpc.io'

gRPC-Swift.podspec

@@ -2,7 +2,7 @@ Pod::Spec.new do |s|
 
     s.name = 'gRPC-Swift'
     s.module_name = 'GRPC'
-    s.version = '1.0.0-alpha.19'
+    s.version = '1.0.0-alpha.20'
     s.license = { :type => 'Apache 2.0', :file => 'LICENSE' }
     s.summary = 'Swift gRPC code generator plugin and runtime library'
     s.homepage = 'https://www.grpc.io'

scripts/build_podspecs.py

@@ -14,29 +14,6 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-"""
-Script for generating the gRPC-Swift and CGRPCZlib Podspec files.
-
-    Usage:
-        usage: build_podspecs.py [-h] [-p PATH] [-u] version
-
-        Build Podspec files for SwiftGRPC
-
-        positional arguments:
-        version
-
-        optional arguments:
-        -h, --help            show this help message and exit
-        -p PATH, --path PATH  The directory where generated podspec files will be
-                                saved. If not passed, defaults to place in the current
-                                working directory.
-        -u, --upload          Determines if the newly built Podspec files should be
-                                pushed.
-
-    Example:
-        'python scripts/build_podspecs.py -u 1.0.0-alpha.11'
-"""
-
 import os
 import json
 import random
@@ -76,9 +53,9 @@ class Pod:
     def as_podspec(self):
         print('\n')
         print('Building Podspec for %s' % self.name)
-        print('-----------------------------------------------------------')
+        print('-' * 80)
 
-        indent='    '
+        indent=' ' * 4
 
         podspec = "Pod::Spec.new do |s|\n\n"
         podspec += indent + "s.name = '%s'\n" % self.name
@@ -111,8 +88,6 @@ class Pod:
         return podspec
 
 class PodManager:
-    pods = []
-
     def __init__(self, directory, version, should_publish):
         self.directory = directory
         self.version = version
@@ -156,13 +131,16 @@ class PodManager:
         grpc_pod.add_dependency(Dependency(cgrpczlib_pod.name))
         grpc_plugins_pod.add_dependency(Dependency(grpc_pod.name))
 
-        self.pods += [cgrpczlib_pod, grpc_pod, grpc_plugins_pod]
+        return [cgrpczlib_pod, grpc_pod, grpc_plugins_pod]
+
+    def go(self, start_from):
+        pods = self.build_pods()
 
-    def go(self):
-        self.build_pods()
+        if start_from:
+            pods = pods[list(pod.name for pod in pods).index(start_from):]
 
         # Create .podspec files and publish
-        for target in self.pods:
+        for target in pods:
             self.write(target.name, target.as_podspec())
             if self.should_publish:
                 self.publish(target.name)
@@ -203,15 +181,13 @@ def dir_path(path):
     raise NotADirectoryError(path)
 
 def main():
-    # Setup
-
-    parser = argparse.ArgumentParser(description='Build Podspec files for SwiftGRPC')
+    parser = argparse.ArgumentParser(description='Build Podspec files for gRPC Swift')
 
     parser.add_argument(
         '-p',
         '--path',
         type=dir_path,
-        help='The directory where generated podspec files will be saved. If not passed, defaults to place in the current working directory.'
+        help='The directory where generated podspec files will be saved. If not passed, defaults to the current working directory.'
     )
 
     parser.add_argument(
@@ -221,6 +197,12 @@ def main():
         help='Determines if the newly built Podspec files should be pushed.'
     )
 
+    parser.add_argument(
+        '-f',
+        '--start-from',
+        help='The name of the Podspec to start from.'
+    )
+
     parser.add_argument('version')
 
     args = parser.parse_args()
@@ -228,12 +210,13 @@ def main():
     should_publish = args.upload
     version = args.version
     path = args.path
+    start_from = args.start_from
 
     if not path:
         path = os.getcwd()
 
     pod_manager = PodManager(path, version, should_publish)
-    pod_manager.go()
+    pod_manager.go(start_from)
 
     return 0