From c58471b6f386d494a8bc19850b470f86d87d018a Mon Sep 17 00:00:00 2001
From: Daniel Morrison <daniel@collectiveidea.com>
Date: Thu, 12 Sep 2024 09:38:07 -0400
Subject: [PATCH 1/5] Look for handlers in both the fully-qualified namespace,
 or root namespace.

Many projects only ever use services in one namespace, but we'll respect them if you want them.
---
 README.md                                     | 21 ++++++++++++++++-
 lib/twirp/rails/dispatcher.rb                 |  8 ++++++-
 .../twirp/example/cobbler/cobbler_handler.rb  | 21 +++++++++++++++++
 .../lib/twirp/example/cobbler/cobbler_pb.rb   | 20 ++++++++++++++++
 .../twirp/example/cobbler/cobbler_twirp.rb    | 23 +++++++++++++++++++
 .../proto/twirp/example/cobbler/cobbler.proto | 23 +++++++++++++++++++
 6 files changed, 114 insertions(+), 2 deletions(-)
 create mode 100644 spec/rails_app/app/handlers/twirp/example/cobbler/cobbler_handler.rb
 create mode 100644 spec/rails_app/lib/twirp/example/cobbler/cobbler_pb.rb
 create mode 100644 spec/rails_app/lib/twirp/example/cobbler/cobbler_twirp.rb
 create mode 100644 spec/rails_app/proto/twirp/example/cobbler/cobbler.proto

diff --git a/README.md b/README.md
index 54d2d60..6d42ec9 100644
--- a/README.md
+++ b/README.md
@@ -86,7 +86,26 @@ end
 
 Each handler method should return the appropriate Protobuf, or a `Twirp::Error`.
 
-TODO: Give more examples of both
+#### Packages and Namespacing
+
+Handlers can live in directories that reflect the service's package. For example, `haberdasher.proto` defines:
+
+```protobuf
+package twirp.example.haberdasher;
+```
+
+You can use the full path, or because many projects have only one namespace, we also let you skip the namespace for simplicity:
+
+We look for the handler in either location:
+
+`app/handlers/twirp/example/haberdasher/haberdasher_service_handler.rb` defines `Twirp::Example::Haberdasher::HaberdasherServiceHandler`
+
+or
+
+`app/handlers/haberdasher_service_handler.rb` defines `HaberdasherServiceHandler`
+
+
+TODO: Give more examples of handlers
 
 ### Familiar Callbacks
 
diff --git a/lib/twirp/rails/dispatcher.rb b/lib/twirp/rails/dispatcher.rb
index 514114e..f51425b 100644
--- a/lib/twirp/rails/dispatcher.rb
+++ b/lib/twirp/rails/dispatcher.rb
@@ -4,7 +4,13 @@ module Twirp
   module Rails
     class Dispatcher
       def initialize(service_class)
-        @service_handler = "#{service_class.service_name}Handler".constantize
+        # Check for a handler in the service's namespace, or in the root namespace
+        # e.g. Twirp::Example::Cobbler::CobblerHandler or ::CobblerHandler
+        @service_handler = if Object.const_defined?("#{service_class.module_parent}::#{service_class.service_name}Handler")
+          "#{service_class.module_parent}::#{service_class.service_name}Handler".constantize
+        else
+          "#{service_class.service_name}Handler".constantize
+        end
       end
 
       def respond_to_missing?(method, *)
diff --git a/spec/rails_app/app/handlers/twirp/example/cobbler/cobbler_handler.rb b/spec/rails_app/app/handlers/twirp/example/cobbler/cobbler_handler.rb
new file mode 100644
index 0000000..69581bf
--- /dev/null
+++ b/spec/rails_app/app/handlers/twirp/example/cobbler/cobbler_handler.rb
@@ -0,0 +1,21 @@
+module Twirp
+  module Example
+    module Cobbler
+      class CobblerHandler < Twirp::Rails::Handler
+        def make_shoe
+          # We can return a Twirp::Error when appropriate
+          if request.inches < 12
+            return Twirp::Error.invalid_argument("is too small", argument: "inches")
+          end
+
+          # Build the reponse
+          Twirp::Example::Cobbler::Shoe.new(
+            inches: request.inches,
+            name: "Pork Pie",
+            color: "Tan"
+          )
+        end
+      end
+    end
+  end
+end
diff --git a/spec/rails_app/lib/twirp/example/cobbler/cobbler_pb.rb b/spec/rails_app/lib/twirp/example/cobbler/cobbler_pb.rb
new file mode 100644
index 0000000..9e0b3d7
--- /dev/null
+++ b/spec/rails_app/lib/twirp/example/cobbler/cobbler_pb.rb
@@ -0,0 +1,20 @@
+# frozen_string_literal: true
+# Generated by the protocol buffer compiler.  DO NOT EDIT!
+# source: twirp/example/cobbler/cobbler.proto
+
+require 'google/protobuf'
+
+
+descriptor_data = "\n#twirp/example/cobbler/cobbler.proto\x12\x15twirp.example.cobbler\"\x16\n\x04Size\x12\x0e\n\x06inches\x18\x01 \x01(\x05\"3\n\x04Shoe\x12\x0e\n\x06inches\x18\x01 \x01(\x05\x12\r\n\x05\x63olor\x18\x02 \x01(\t\x12\x0c\n\x04name\x18\x03 \x01(\t2O\n\x07\x43obbler\x12\x44\n\x08MakeShoe\x12\x1b.twirp.example.cobbler.Size\x1a\x1b.twirp.example.cobbler.Shoeb\x06proto3"
+
+pool = Google::Protobuf::DescriptorPool.generated_pool
+pool.add_serialized_file(descriptor_data)
+
+module Twirp
+  module Example
+    module Cobbler
+      Size = ::Google::Protobuf::DescriptorPool.generated_pool.lookup("twirp.example.cobbler.Size").msgclass
+      Shoe = ::Google::Protobuf::DescriptorPool.generated_pool.lookup("twirp.example.cobbler.Shoe").msgclass
+    end
+  end
+end
diff --git a/spec/rails_app/lib/twirp/example/cobbler/cobbler_twirp.rb b/spec/rails_app/lib/twirp/example/cobbler/cobbler_twirp.rb
new file mode 100644
index 0000000..c05e46c
--- /dev/null
+++ b/spec/rails_app/lib/twirp/example/cobbler/cobbler_twirp.rb
@@ -0,0 +1,23 @@
+# frozen_string_literal: true
+
+# Generated by the protoc-gen-twirp_ruby gem v1.1.1. DO NOT EDIT!
+# source: twirp/example/cobbler/cobbler.proto
+
+require "twirp"
+require_relative "cobbler_pb"
+
+module Twirp
+  module Example
+    module Cobbler
+      class CobblerService < ::Twirp::Service
+        package "twirp.example.cobbler"
+        service "Cobbler"
+        rpc :MakeShoe, Size, Shoe, ruby_method: :make_shoe
+      end
+
+      class CobblerClient < ::Twirp::Client
+        client_for CobblerService
+      end
+    end
+  end
+end
diff --git a/spec/rails_app/proto/twirp/example/cobbler/cobbler.proto b/spec/rails_app/proto/twirp/example/cobbler/cobbler.proto
new file mode 100644
index 0000000..36b2048
--- /dev/null
+++ b/spec/rails_app/proto/twirp/example/cobbler/cobbler.proto
@@ -0,0 +1,23 @@
+// A close copy of haberdasher.proto
+// We're putting this in /proto/twirp/example/ so that we can test namespace handling
+syntax = "proto3";
+
+package twirp.example.cobbler;
+
+// Cobbler service makes shoes for clients.
+service Cobbler {
+  // MakeShoe produces a shoe of mysterious, randomly-selected color!
+  rpc MakeShoe(Size) returns (Shoe);
+}
+
+// Size of a Shoe, in inches.
+message Size {
+  int32 inches = 1; // must be > 0
+}
+
+// A Shoe is a piece of footwear made by a Cobbler.
+message Shoe {
+  int32 inches = 1;
+  string color = 2; // anything but "invisible"
+  string name = 3; // i.e. "oxford"
+}

From 0e1157bf9675f1e7e80858c0dbb64b176c2129ca Mon Sep 17 00:00:00 2001
From: Daniel Morrison <daniel@collectiveidea.com>
Date: Thu, 12 Sep 2024 09:43:25 -0400
Subject: [PATCH 2/5] Have standard ignore generated files

---
 .standard.yml | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/.standard.yml b/.standard.yml
index 8de184f..efc21a1 100644
--- a/.standard.yml
+++ b/.standard.yml
@@ -2,3 +2,6 @@ ruby_version: 2.7
 plugins:
   - standard-performance
   - standard-rails
+ignore:
+  - '**/*_pb.rb'
+  - '**/*_twirp.rb' 

From 1adcf0fb390ed4b18c54a85ccb7e9f9ed78b1ac6 Mon Sep 17 00:00:00 2001
From: Daniel Morrison <daniel@collectiveidea.com>
Date: Thu, 12 Sep 2024 09:45:57 -0400
Subject: [PATCH 3/5] Regenerate haberdasher files

---
 spec/rails_app/lib/haberdasher_pb.rb    | 22 ++++++++--------------
 spec/rails_app/lib/haberdasher_twirp.rb |  6 +++++-
 2 files changed, 13 insertions(+), 15 deletions(-)

diff --git a/spec/rails_app/lib/haberdasher_pb.rb b/spec/rails_app/lib/haberdasher_pb.rb
index 37d5652..ec73d3e 100644
--- a/spec/rails_app/lib/haberdasher_pb.rb
+++ b/spec/rails_app/lib/haberdasher_pb.rb
@@ -1,20 +1,14 @@
+# frozen_string_literal: true
 # Generated by the protocol buffer compiler.  DO NOT EDIT!
-# source: lib/haberdasher.proto
+# source: haberdasher.proto
 
-require "google/protobuf"
+require 'google/protobuf'
 
-Google::Protobuf::DescriptorPool.generated_pool.build do
-  add_file("lib/haberdasher.proto", syntax: :proto3) do
-    add_message "twirp.example.haberdasher.Size" do
-      optional :inches, :int32, 1
-    end
-    add_message "twirp.example.haberdasher.Hat" do
-      optional :inches, :int32, 1
-      optional :color, :string, 2
-      optional :name, :string, 3
-    end
-  end
-end
+
+descriptor_data = "\n\x11haberdasher.proto\x12\x19twirp.example.haberdasher\"\x16\n\x04Size\x12\x0e\n\x06inches\x18\x01 \x01(\x05\"2\n\x03Hat\x12\x0e\n\x06inches\x18\x01 \x01(\x05\x12\r\n\x05\x63olor\x18\x02 \x01(\t\x12\x0c\n\x04name\x18\x03 \x01(\t2Y\n\x0bHaberdasher\x12J\n\x07MakeHat\x12\x1f.twirp.example.haberdasher.Size\x1a\x1e.twirp.example.haberdasher.Hatb\x06proto3"
+
+pool = Google::Protobuf::DescriptorPool.generated_pool
+pool.add_serialized_file(descriptor_data)
 
 module Twirp
   module Example
diff --git a/spec/rails_app/lib/haberdasher_twirp.rb b/spec/rails_app/lib/haberdasher_twirp.rb
index 442a036..588d5aa 100644
--- a/spec/rails_app/lib/haberdasher_twirp.rb
+++ b/spec/rails_app/lib/haberdasher_twirp.rb
@@ -1,4 +1,8 @@
-# Code generated by protoc-gen-twirp_ruby 1.10.0, DO NOT EDIT.
+# frozen_string_literal: true
+
+# Generated by the protoc-gen-twirp_ruby gem v1.1.1. DO NOT EDIT!
+# source: haberdasher.proto
+
 require "twirp"
 require_relative "haberdasher_pb"
 

From 97ae01b3cf50717165b206a7d737279c76a1a841 Mon Sep 17 00:00:00 2001
From: Daniel Morrison <daniel@collectiveidea.com>
Date: Thu, 12 Sep 2024 09:59:58 -0400
Subject: [PATCH 4/5] Fix comment

---
 spec/rails_app/proto/twirp/example/cobbler/cobbler.proto | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/spec/rails_app/proto/twirp/example/cobbler/cobbler.proto b/spec/rails_app/proto/twirp/example/cobbler/cobbler.proto
index 36b2048..c820e2d 100644
--- a/spec/rails_app/proto/twirp/example/cobbler/cobbler.proto
+++ b/spec/rails_app/proto/twirp/example/cobbler/cobbler.proto
@@ -1,5 +1,5 @@
 // A close copy of haberdasher.proto
-// We're putting this in /proto/twirp/example/ so that we can test namespace handling
+// We're putting this in /proto/twirp/example/cobbler/ so that we can test namespace handling
 syntax = "proto3";
 
 package twirp.example.cobbler;

From 8c387b0d4ef1ffc902412b86cc804552c7950ff7 Mon Sep 17 00:00:00 2001
From: Daniel Morrison <daniel@collectiveidea.com>
Date: Thu, 12 Sep 2024 10:09:17 -0400
Subject: [PATCH 5/5] Specify minimum standard version to fix Ruby 2.7 builds

---
 Gemfile | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Gemfile b/Gemfile
index c4bf4bc..e15d092 100644
--- a/Gemfile
+++ b/Gemfile
@@ -10,6 +10,6 @@ gem "rake"
 gem "debug"
 gem "rspec-rails"
 gem "sqlite3", "~> 1.4"
-gem "standard"
+gem "standard", ">= 1.35.1"
 gem "standard-performance"
 gem "standard-rails"