feat: Add support for unix socket path and secure connection (#8)

Signed-off-by: Jose Colella <jose.colella@gusto.com>
Signed-off-by: Jose Miguel Colella <josecolella@yahoo.com>
Co-authored-by: Skye Gill <gill.skye95@gmail.com>
Co-authored-by: Todd Baert <toddbaert@gmail.com>
Co-authored-by: Josh Nichols <josh@technicalpickles.com>

providers/openfeature-flagd-provider/README.md

@@ -23,22 +23,58 @@ gem install openfeature-flagd-provider
 
 ## Usage
 
-The provider allows for configuration of host, port, socket_path, and tls connection.
+The `OpenFeature::FlagD` supports multiple configuration options that dictate how the SDK communicates with flagd.
+Options can be defined in the constructor or as environment variables, with constructor options having the highest precedence.
+
+### Available options
+
+| Option name       | Environment variable name | Type    | Default   |
+| -----------       | ------------------------- | ------- | --------- |
+| host              | FLAGD_HOST                | string  | localhost |
+| port              | FLAGD_PORT                | number  | 8013      |
+| tls               | FLAGD_TLS                 | boolean | false     |
+| unix_socket_path  | FLAGD_SOCKET_PATH         | string  | nil       |
+| root_cert_path    | FLAGD_SERVER_CERT_PATH    | string  | nil       |
+
+### Example using TCP
 
 ```ruby
-OpenFeature::FlagD::Provider.configure do |config|
-    config.host = "localhost"
-    config.port = 8013
-    config.tls = false
+OpenFeature::SDK.configure do |config|
+    # your provider of choice
+    config.provider = OpenFeature::FlagD::Provider.configure do |provider_config|
+        provider_config.host = "localhost"
+        provider_config.port = 8013
+        provider_config.tls = false
+    end
 end
 ```
 
-If no configurations are provided, the provider will be initialized with the following environment variables:
+### Example using a Unix socket
+
+```ruby
+OpenFeature::SDK.configure do |config|
+    # your provider of choice
+    config.provider = OpenFeature::FlagD::Provider.configure do |provider_config|
+        provider_config.unix_socket_path = "tmp/flagd.sock"
+    end
+end
+```
+
+
+### Example using a secure connection
+
+```ruby
+OpenFeature::SDK.configure do |config|
+    # your provider of choice
+    config.provider = OpenFeature::FlagD::Provider.configure do |provider_config|
+        provider_config.host = "localhost"
+        provider_config.port = 8013
+        provider_config.tls = true
+        provider_config.root_cert_path = './ca.pem'
+    end
+end
+```
 
-> FLAGD_HOST
-> FLAGD_PORT
-> FLAGD_TLS
-> FLAGD_SOCKET_PATH
 
 If no environment variables are set the [default configuration](./lib/openfeature/flagd/provider/configuration.rb) is set
 

providers/openfeature-flagd-provider/lib/openfeature/flagd/provider.rb

@@ -1,5 +1,7 @@
 # frozen_string_literal: true
 
+require "grpc"
+
 require_relative "provider/configuration"
 require_relative "provider/client"
 
@@ -15,7 +17,7 @@ module FlagD
     #     config.port = 8379
     #     config.tls = false
     #   end
-    # The Provider providers the following methods and attributes:
+    # The Provider provides the following methods and attributes:
     #
     # * <tt>metadata</tt> - Returns the associated provider metadata with the name
     #
@@ -29,7 +31,7 @@ module FlagD
     #   manner; <tt>client.resolve_float_value(flag_key: 'float-flag', default_value: 2.0)</tt>
     #
     # * <tt>resolve_string_value(flag_key:, default_value:, context: nil)</tt>
-    #   manner; <tt>client.resolve_string_value(flag_key: 'string-flag', default_value: 'some-defau;t-value')</tt>
+    #   manner; <tt>client.resolve_string_value(flag_key: 'string-flag', default_value: 'some-default-value')</tt>
     #
     # * <tt>resolve_object_value(flag_key:, default_value:, context: nil)</tt>
     #   manner; <tt>client.resolve_object_value(flag_key: 'object-flag', default_value: { default_value: 'value'})</tt>

providers/openfeature-flagd-provider/lib/openfeature/flagd/provider/client.rb

@@ -1,40 +1,42 @@
 # frozen_string_literal: true
 
+require "grpc"
+
 require_relative "schema/v1/schema_services_pb"
 require_relative "configuration"
-
 module OpenFeature
   module FlagD
     module Provider
       # Client represents a wrapper for the GRPC stub that allows for resolution of boolean, string, number, and object
       # values. The implementation follows the details specified in https://docs.openfeature.dev/docs/specification/sections/providers
       #
       #
-      # Within the Client instance, the following methods are available:
+      # The Client provides the following methods and attributes:
+      #
+      # * <tt>metadata</tt> - Returns the associated provider metadata with the name
       #
-      # * <tt>resolve_boolean_value(flag_key:, default_value:, context: nil)</tt> -
-      #   Resolves the boolean value of the flag_key
+      # * <tt>resolve_boolean_value(flag_key:, default_value:, context: nil)</tt>
       #   manner; <tt>client.resolve_boolean(flag_key: 'boolean-flag', default_value: false)</tt>
       #
-      # * <tt>resolve_integer_value(flag_key:, default_value:, context: nil)</tt> - Resolves the
-      #   manner; <tt>client.resolve_boolean = File.read('path/to/filename.png')</tt>
-
-      # * <tt>resolve_integer_value</tt> - Allows you to specify any header field in your email such
-      #   as <tt>headers['X-No-Spam'] = 'True'</tt>. Note that declaring a header multiple times
-      #   will add many fields of the same name. Read #headers doc for more information.
+      # * <tt>resolve_integer_value(flag_key:, default_value:, context: nil)</tt>
+      #   manner; <tt>client.resolve_integer_value(flag_key: 'integer-flag', default_value: 2)</tt>
+      #
+      # * <tt>resolve_float_value(flag_key:, default_value:, context: nil)</tt>
+      #   manner; <tt>client.resolve_float_value(flag_key: 'float-flag', default_value: 2.0)</tt>
+      #
+      # * <tt>resolve_string_value(flag_key:, default_value:, context: nil)</tt>
+      #   manner; <tt>client.resolve_string_value(flag_key: 'string-flag', default_value: 'some-default-value')</tt>
       #
+      # * <tt>resolve_object_value(flag_key:, default_value:, context: nil)</tt>
+      #   manner; <tt>client.resolve_object_value(flag_key: 'flag', default_value: { default_value: 'value'})</tt>
       class Client
         attr_reader :metadata
 
         def initialize(configuration: nil)
-          @configuration = Configuration.default_config
-                                        .merge(Configuration.environment_variables_config)
-                                        .merge(configuration)
+          @configuration = configuration.freeze
           @metadata = Metadata.new(PROVIDER_NAME).freeze
-          @grpc_client = Grpc::Service::Stub.new(
-            "#{@configuration.host}:#{@configuration.port}",
-            :this_channel_is_insecure
-          ).freeze
+
+          @grpc_client = build_client(configuration)
         end
 
         PROVIDER_NAME = "flagd Provider"
@@ -74,6 +76,26 @@ def resolve_#{type}_value(flag_key:, default_value:, context: nil)
         def error_response(error_code, error_message)
           ResolutionDetails.new(error_code, error_message, "ERROR", nil, nil).to_h.freeze
         end
+
+        def grpc_client(configuration)
+          return @grpc_client unless defined?(@grpc_client)
+
+          options = :this_channel_is_insecure
+          if configuration.tls
+            options = GRPC::Core::ChannelCredentials.new(
+              configuration.root_certs
+            )
+          end
+          @grpc_client = Grpc::Service::Stub.new(build_server_address(configuration), options).freeze
+        end
+
+        def server_address
+          @server_address ||= if @configuration.unix_socket_path
+            "unix://#{configuration.unix_socket_path}"
+          else
+            "#{@configuration.host}:#{@configuration.port}"
+          end
+        end
       end
     end
   end

providers/openfeature-flagd-provider/lib/openfeature/flagd/provider/configuration.rb

@@ -7,12 +7,14 @@ module Provider
       # This class is not meant to be interacted with directly but instead through the
       # <tt>OpenFeature::FlagD::Provider.configure</tt> method
       class Configuration
-        attr_accessor :host, :port, :tls
+        attr_accessor :host, :port, :tls, :unix_socket_path, :root_cert_path
 
         ENVIRONMENT_CONFIG_NAME = {
           host: "FLAGD_HOST",
           port: "FLAGD_PORT",
-          tls: "FLAGD_TLS"
+          tls: "FLAGD_TLS",
+          unix_socket_path: "FLAGD_SOCKET_PATH",
+          root_cert_path: "FLAGD_SERVER_CERT_PATH"
         }.freeze
 
         def merge(other_configuration)
@@ -21,6 +23,13 @@ def merge(other_configuration)
           @host = other_configuration.host if !other_configuration.host.nil? && @host.nil?
           @port = other_configuration.port if !other_configuration.port.nil? && @port.nil?
           @tls = other_configuration.tls if !other_configuration.tls.nil? && @tls.nil?
+          if !other_configuration.unix_socket_path.nil? && @unix_socket_path.nil?
+            @unix_socket_path = other_configuration.unix_socket_path
+          end
+          if !other_configuration.root_cert_path.nil? && @root_cert.nil?
+            @root_cert = File.read(other_configuration.root_cert_path)
+          end
+
           self
         end
 
@@ -38,6 +47,14 @@ def self.environment_variables_config
             configuration.tls = ENV.fetch(ENVIRONMENT_CONFIG_NAME[:tls],
                                           nil) == "true"
           end
+          unless ENV[ENVIRONMENT_CONFIG_NAME[:unix_socket_path]].nil?
+            configuration.unix_socket_path = ENV.fetch(ENVIRONMENT_CONFIG_NAME[:unix_socket_path],
+                                                       nil)
+          end
+          unless ENV[ENVIRONMENT_CONFIG_NAME[:root_cert_path]].nil?
+            root_cert_path = ENV.fetch(ENVIRONMENT_CONFIG_NAME[:root_cert_path], nil)
+            configuration.root_cert = File.read(root_cert_path)
+          end
 
           configuration
         end
@@ -47,6 +64,8 @@ def self.default_config
           configuration.host = "localhost"
           configuration.port = 8013
           configuration.tls = false
+          configuration.unix_socket_path = nil
+          configuration.root_cert_path = nil
           configuration
         end
       end

providers/openfeature-flagd-provider/spec/openfeature/flagd/provider/client_spec.rb

@@ -4,13 +4,14 @@
 
 # https://docs.openfeature.dev/docs/specification/sections/providers
 RSpec.describe OpenFeature::FlagD::Provider::Client do
-  subject(:client) { described_class.new }
+  let(:configuration) { OpenFeature::FlagD::Provider::Configuration.default_config }
+  subject(:client) { described_class.new(configuration: configuration) }
 
   context "https://docs.openfeature.dev/docs/specification/sections/providers#requirement-211" do
     it do
       expect(client).to respond_to(:metadata)
       expect(client.metadata).to respond_to(:name)
-      expect(client.metadata.name).to eq("Flagd Provider")
+      expect(client.metadata.name).to eq("flagd Provider")
     end
   end
 

providers/openfeature-flagd-provider/spec/openfeature/flagd/provider_spec.rb

@@ -73,7 +73,7 @@
     it "metadata name is defined" do
       expect(described_class).to respond_to(:metadata)
       expect(described_class.metadata).to respond_to(:name)
-      expect(described_class.metadata.name).to eq("Flagd Provider")
+      expect(described_class.metadata.name).to eq("flagd Provider")
     end
   end
 end