feat: add TLS configuration support to Ruby SDK and enable HTTPS testing

- Add TlsConfig class with comprehensive TLS options matching Python/Java implementations
- Support CA certificates, client certificates for mutual TLS, and insecure mode
- Add convenience factory methods for common TLS scenarios
- Update integration test framework to use HTTPS with TLS certificates for Ruby tests
- Add comprehensive README documentation with TLS configuration examples

Author: markphelps

flipt-client-ruby/README.md

@@ -114,6 +114,7 @@ The `Flipt::Client` constructor accepts the following keyword arguments:
 - `fetch_mode`: The fetch mode to use. Defaults to polling.
 - `error_strategy`: The error strategy to use. Defaults to fail. See [Error Strategies](#error-strategies).
 - `snapshot`: The snapshot to use when initializing the client. Defaults to no snapshot. See [Snapshotting](#snapshotting).
+- `tls_config`: The TLS configuration for connecting to servers with custom certificates. See [TLS Configuration](#tls-configuration).
 
 ### Authentication
 
@@ -123,6 +124,108 @@ The `Flipt::Client` supports the following authentication strategies:
 - [Client Token Authentication](https://docs.flipt.io/authentication/using-tokens)
 - [JWT Authentication](https://docs.flipt.io/authentication/using-jwts)
 
+### TLS Configuration
+
+The `Flipt::Client` supports configuring TLS settings for secure connections to Flipt servers. This is useful when:
+
+- Connecting to Flipt servers with self-signed certificates
+- Using custom Certificate Authorities (CAs)  
+- Implementing mutual TLS authentication
+- Testing with insecure connections (development only)
+
+#### Basic TLS with Custom CA Certificate
+
+```ruby
+# Using a CA certificate file
+tls_config = Flipt::TlsConfig.with_ca_cert_file('/path/to/ca.pem')
+
+client = Flipt::Client.new(
+  url: 'https://flipt.example.com',
+  tls_config: tls_config
+)
+```
+
+```ruby
+# Using CA certificate data directly
+ca_cert_data = File.read('/path/to/ca.pem')
+tls_config = Flipt::TlsConfig.with_ca_cert_data(ca_cert_data)
+
+client = Flipt::Client.new(
+  url: 'https://flipt.example.com',
+  tls_config: tls_config
+)
+```
+
+#### Mutual TLS Authentication
+
+```ruby
+# Using certificate and key files
+tls_config = Flipt::TlsConfig.with_mutual_tls('/path/to/client.pem', '/path/to/client.key')
+
+client = Flipt::Client.new(
+  url: 'https://flipt.example.com',
+  tls_config: tls_config
+)
+```
+
+```ruby
+# Using certificate and key data directly
+client_cert_data = File.read('/path/to/client.pem')
+client_key_data = File.read('/path/to/client.key')
+
+tls_config = Flipt::TlsConfig.with_mutual_tls_data(client_cert_data, client_key_data)
+
+client = Flipt::Client.new(
+  url: 'https://flipt.example.com',
+  tls_config: tls_config
+)
+```
+
+#### Advanced TLS Configuration
+
+```ruby
+# Full TLS configuration with all options
+tls_config = Flipt::TlsConfig.new(
+  ca_cert_file: '/path/to/ca.pem',
+  client_cert_file: '/path/to/client.pem',
+  client_key_file: '/path/to/client.key',
+  insecure_skip_verify: false
+)
+
+client = Flipt::Client.new(
+  url: 'https://flipt.example.com',
+  tls_config: tls_config
+)
+```
+
+#### Development Mode (Insecure)
+
+**⚠️ WARNING: Only use this in development environments!**
+
+```ruby
+# Skip certificate verification (NOT for production)
+tls_config = Flipt::TlsConfig.insecure
+
+client = Flipt::Client.new(
+  url: 'https://localhost:8443',
+  tls_config: tls_config
+)
+```
+
+#### TLS Configuration Options
+
+The `TlsConfig` class supports the following options:
+
+- `ca_cert_file`: Path to custom CA certificate file (PEM format)
+- `ca_cert_data`: Raw CA certificate content (PEM format) - takes precedence over `ca_cert_file`
+- `insecure_skip_verify`: Skip certificate verification (development only)
+- `client_cert_file`: Client certificate file for mutual TLS (PEM format)
+- `client_key_file`: Client private key file for mutual TLS (PEM format)
+- `client_cert_data`: Raw client certificate content (PEM format) - takes precedence over `client_cert_file`
+- `client_key_data`: Raw client private key content (PEM format) - takes precedence over `client_key_file`
+
+> **Note**: When both file paths and data are provided, the data fields take precedence. For example, if both `ca_cert_file` and `ca_cert_data` are set, `ca_cert_data` will be used.
+
 ### Error Strategies
 
 The client supports the following error strategies:

flipt-client-ruby/lib/flipt_client.rb

@@ -65,12 +65,14 @@ def self.libfile
     #   Note: Streaming is currently only supported when using the SDK with Flipt Cloud or Flipt v2.
     # @option opts [Symbol] :error_strategy error strategy to use for the client (:fail or :fallback).
     # @option opts [String] :snapshot snapshot to use when initializing the client
+    # @option opts [TlsConfig] :tls_config TLS configuration for connecting to servers with custom certificates
     def initialize(**opts)
       @namespace = opts.fetch(:namespace, 'default')
 
       opts[:authentication] = validate_authentication(opts.fetch(:authentication, NoAuthentication.new))
       opts[:fetch_mode] = validate_fetch_mode(opts.fetch(:fetch_mode, :polling))
       opts[:error_strategy] = validate_error_strategy(opts.fetch(:error_strategy, :fail))
+      opts[:tls_config] = validate_tls_config(opts.fetch(:tls_config, nil))
 
       @engine = self.class.initialize_engine(opts.to_json)
       ObjectSpace.define_finalizer(self, self.class.finalize(@engine))
@@ -223,6 +225,13 @@ def validate_error_strategy(error_strategy)
 
       raise ValidationError, 'invalid error strategy'
     end
+
+    def validate_tls_config(tls_config)
+      return nil if tls_config.nil?
+      return tls_config.to_h if tls_config.is_a?(TlsConfig)
+
+      raise ValidationError, 'invalid tls_config: must be TlsConfig instance'
+    end
   end
 
   # Deprecation shim for EvaluationClient

flipt-client-ruby/lib/flipt_client/models.rb

@@ -41,6 +41,107 @@ def strategy
     end
   end
 
+  # TlsConfig provides configuration for TLS connections to Flipt servers
+  class TlsConfig
+    attr_reader :ca_cert_file, :ca_cert_data, :insecure_skip_verify,
+                :client_cert_file, :client_key_file, :client_cert_data, :client_key_data
+
+    # Initialize TLS configuration
+    #
+    # @param ca_cert_file [String, nil] Path to CA certificate file (PEM format)
+    # @param ca_cert_data [String, nil] Raw CA certificate content (PEM format)
+    # @param insecure_skip_verify [Boolean, nil] Skip certificate verification (development only)
+    # @param client_cert_file [String, nil] Path to client certificate file (PEM format)
+    # @param client_key_file [String, nil] Path to client key file (PEM format)
+    # @param client_cert_data [String, nil] Raw client certificate content (PEM format)
+    # @param client_key_data [String, nil] Raw client key content (PEM format)
+    def initialize(ca_cert_file: nil, ca_cert_data: nil, insecure_skip_verify: nil,
+                   client_cert_file: nil, client_key_file: nil, 
+                   client_cert_data: nil, client_key_data: nil)
+      @ca_cert_file = ca_cert_file
+      @ca_cert_data = ca_cert_data
+      @insecure_skip_verify = insecure_skip_verify
+      @client_cert_file = client_cert_file
+      @client_key_file = client_key_file
+      @client_cert_data = client_cert_data
+      @client_key_data = client_key_data
+
+      validate_files!
+    end
+
+    # Create TLS config for insecure connections (development only)
+    # WARNING: Only use this in development environments
+    #
+    # @return [TlsConfig] TLS config with certificate verification disabled
+    def self.insecure
+      new(insecure_skip_verify: true)
+    end
+
+    # Create TLS config with CA certificate file
+    #
+    # @param ca_cert_file [String] Path to CA certificate file
+    # @return [TlsConfig] TLS config with custom CA certificate
+    def self.with_ca_cert_file(ca_cert_file)
+      new(ca_cert_file: ca_cert_file)
+    end
+
+    # Create TLS config with CA certificate data
+    #
+    # @param ca_cert_data [String] CA certificate content in PEM format
+    # @return [TlsConfig] TLS config with custom CA certificate
+    def self.with_ca_cert_data(ca_cert_data)
+      new(ca_cert_data: ca_cert_data)
+    end
+
+    # Create TLS config for mutual TLS with certificate files
+    #
+    # @param client_cert_file [String] Path to client certificate file
+    # @param client_key_file [String] Path to client key file
+    # @return [TlsConfig] TLS config with mutual TLS
+    def self.with_mutual_tls(client_cert_file, client_key_file)
+      new(client_cert_file: client_cert_file, client_key_file: client_key_file)
+    end
+
+    # Create TLS config for mutual TLS with certificate data
+    #
+    # @param client_cert_data [String] Client certificate content in PEM format
+    # @param client_key_data [String] Client key content in PEM format
+    # @return [TlsConfig] TLS config with mutual TLS
+    def self.with_mutual_tls_data(client_cert_data, client_key_data)
+      new(client_cert_data: client_cert_data, client_key_data: client_key_data)
+    end
+
+    # Convert to hash for JSON serialization
+    # @return [Hash] TLS configuration as hash
+    def to_h
+      hash = {}
+      hash[:ca_cert_file] = @ca_cert_file if @ca_cert_file
+      hash[:ca_cert_data] = @ca_cert_data if @ca_cert_data
+      hash[:insecure_skip_verify] = @insecure_skip_verify unless @insecure_skip_verify.nil?
+      hash[:client_cert_file] = @client_cert_file if @client_cert_file
+      hash[:client_key_file] = @client_key_file if @client_key_file
+      hash[:client_cert_data] = @client_cert_data if @client_cert_data
+      hash[:client_key_data] = @client_key_data if @client_key_data
+      hash
+    end
+
+    private
+
+    def validate_files!
+      validate_file_exists(@ca_cert_file, 'CA certificate file') if @ca_cert_file
+      validate_file_exists(@client_cert_file, 'Client certificate file') if @client_cert_file
+      validate_file_exists(@client_key_file, 'Client key file') if @client_key_file
+    end
+
+    def validate_file_exists(file_path, description)
+      return if file_path.nil? || file_path.strip.empty?
+      
+      unless File.exist?(file_path)
+        raise ValidationError, "#{description} does not exist: #{file_path}"
+      end
+    end
+  end
+
   # VariantEvaluationResponse
   # @attr_reader [String] flag_key
   # @attr_reader [Boolean] match

flipt-client-ruby/spec/client_spec.rb

@@ -6,7 +6,24 @@
   before(:all) do
     url = ENV.fetch('FLIPT_URL', 'http://localhost:8080')
     auth_token = ENV.fetch('FLIPT_AUTH_TOKEN', 'secret')
-    @client = Flipt::Client.new(url: url, authentication: Flipt::ClientTokenAuthentication.new(auth_token))
+    
+    # Configure TLS if HTTPS URL is provided
+    tls_config = nil
+    if url.start_with?('https://')
+      ca_cert_path = ENV['FLIPT_CA_CERT_PATH']
+      if ca_cert_path && !ca_cert_path.empty?
+        tls_config = Flipt::TlsConfig.with_ca_cert_file(ca_cert_path)
+      else
+        # Fallback to insecure for local testing
+        tls_config = Flipt::TlsConfig.insecure
+      end
+    end
+
+    @client = Flipt::Client.new(
+      url: url, 
+      authentication: Flipt::ClientTokenAuthentication.new(auth_token),
+      tls_config: tls_config
+    )
   end
 
   describe '#evaluate_variant' do

test/main.go

@@ -81,9 +81,9 @@ var (
 	}
 
 	rubyVersions = []containerConfig{
-		{base: "ruby:3.1-bookworm"},
-		{base: "ruby:3.1-bullseye"},
-		{base: "ruby:3.1-alpine", setup: []string{"apk update", "apk add --no-cache build-base"}},
+		{base: "ruby:3.1-bookworm", useHTTPS: true},
+		{base: "ruby:3.1-bullseye", useHTTPS: true},
+		{base: "ruby:3.1-alpine", setup: []string{"apk update", "apk add --no-cache build-base"}, useHTTPS: true},
 	}
 
 	javaVersions = []containerConfig{
@@ -447,8 +447,10 @@ func rubyTests(ctx context.Context, root *dagger.Container, t *testCase) error {
 		WithWorkdir("/src").
 		WithDirectory("/src", t.hostDir.Directory("flipt-client-ruby")).
 		WithDirectory("/src/lib/ext/linux_"+string(t.arch), t.engine.Directory(libDir)).
+		WithDirectory("/src/test/fixtures/tls", t.hostDir.Directory("test/fixtures/tls")).
 		WithServiceBinding("flipt", t.flipt.AsService()).
-		WithEnvVariable("FLIPT_URL", "http://flipt:8080").
+		WithEnvVariable("FLIPT_URL", "https://flipt:8443").
+		WithEnvVariable("FLIPT_CA_CERT_PATH", "/src/test/fixtures/tls/ca.crt").
 		WithEnvVariable("FLIPT_AUTH_TOKEN", "secret").
 		WithExec(args("bundle install")).
 		WithExec(args("bundle exec rspec")).