CI rehearsal only (do not merge)

docs/paykit-interface.md

@@ -269,7 +269,6 @@ conformant.
 - Add `accepts?(protocol)` on `Gate`; keep `x402_accepted?` / `mpp_accepted?`
   as deprecated aliases for one release.
 - Add `payer` and ensure `scheme` on `Payment`.
-- Add `PayKit.configure_from_env`.
 - Stablecoin set: add `USDG`, `CASH`.
 - Wire `external_id` through every flow (currently inconsistent).
 

ruby/lib/pay_kit/config.rb

@@ -264,6 +264,21 @@ def configure
       @config
     end
 
+    def configure_from_env(prefix = "PAY_KIT_", env: ENV)
+      vars = env.to_h.select { |k, _| k.start_with?(prefix) }.transform_keys { |k| k.delete_prefix(prefix) }
+      configure do |c|
+        c.network = vars["NETWORK"] if vars.key?("NETWORK")
+        c.rpc_url = vars["RPC_URL"] if vars.key?("RPC_URL")
+        c.accept = split_env_list(vars["ACCEPT"]) if vars.key?("ACCEPT")
+        c.stablecoins = split_env_list(vars["STABLECOINS"]) if vars.key?("STABLECOINS")
+        c.preflight = parse_env_boolean(vars["PREFLIGHT"], "#{prefix}PREFLIGHT") if vars.key?("PREFLIGHT")
+        c.mpp.realm = vars["MPP_REALM"] if vars.key?("MPP_REALM")
+        c.mpp.challenge_binding_secret = vars["MPP_CHALLENGE_BINDING_SECRET"] if vars.key?("MPP_CHALLENGE_BINDING_SECRET")
+        c.mpp.expires_in = parse_env_integer(vars["MPP_EXPIRES_IN"], "#{prefix}MPP_EXPIRES_IN") if vars.key?("MPP_EXPIRES_IN")
+        c.x402.facilitator_url = vars["X402_FACILITATOR_URL"] if vars.key?("X402_FACILITATOR_URL")
+      end
+    end
+
     def config
       @config ||= Config.new
     end
@@ -279,5 +294,25 @@ def reset!
       @config = nil
       @pricing = nil
     end
+
+    private
+
+    def split_env_list(value)
+      value.split(",").map(&:strip).reject(&:empty?)
+    end
+
+    def parse_env_boolean(value, key)
+      case value.strip.downcase
+      when "true", "1" then true
+      when "false", "0" then false
+      else raise ConfigurationError, "#{key} must be true, false, 1 or 0, got #{value.inspect}"
+      end
+    end
+
+    def parse_env_integer(value, key)
+      Integer(value.strip, 10)
+    rescue ArgumentError
+      raise ConfigurationError, "#{key} must be an integer, got #{value.inspect}"
+    end
   end
 end

ruby/test/pay_kit/config_test.rb

@@ -291,6 +291,62 @@ def test_x402_unknown_scheme_raises
     end
   end
 
+  # --- configure_from_env ----------------------------------------------
+
+  def test_configure_from_env_reads_scalars
+    env = {
+      "PAY_KIT_NETWORK" => "solana_devnet",
+      "PAY_KIT_RPC_URL" => "https://helius.example.com",
+      "PAY_KIT_PREFLIGHT" => "FALSE",
+      "PAY_KIT_MPP_REALM" => "Shop",
+      "PAY_KIT_MPP_CHALLENGE_BINDING_SECRET" => "rotate-me",
+      "PAY_KIT_MPP_EXPIRES_IN" => "90",
+      "PAY_KIT_X402_FACILITATOR_URL" => "https://facilitator.example.com"
+    }
+    config = PayKit.configure_from_env(env: env)
+    assert config.frozen?
+    assert_equal :solana_devnet, config.network
+    assert_equal "https://helius.example.com", config.rpc_url
+    refute config.preflight
+    assert_equal "Shop", config.mpp.realm
+    assert_equal "rotate-me", config.mpp.challenge_binding_secret
+    assert_equal 90, config.mpp.expires_in
+    assert_equal "https://facilitator.example.com", config.x402.facilitator_url
+  end
+
+  def test_configure_from_env_splits_lists
+    config = PayKit.configure_from_env(env: {"PAY_KIT_ACCEPT" => "x402, mpp", "PAY_KIT_STABLECOINS" => "USDC,PYUSD"})
+    assert_equal %i[x402 mpp], config.accept
+    assert_equal %i[USDC PYUSD], config.stablecoins
+  end
+
+  def test_configure_from_env_keeps_defaults_when_unset
+    config = PayKit.configure_from_env(env: {})
+    assert_equal :solana_localnet, config.network
+    assert_equal %i[x402 mpp], config.accept
+    assert_equal %i[USDC], config.stablecoins
+    assert_equal 300, config.mpp.expires_in
+  end
+
+  def test_configure_from_env_custom_prefix
+    config = PayKit.configure_from_env("APP_", env: {"APP_NETWORK" => "solana_devnet", "PAY_KIT_NETWORK" => "bitcoin"})
+    assert_equal :solana_devnet, config.network
+  end
+
+  def test_configure_from_env_rejects_bad_values
+    {
+      "PAY_KIT_NETWORK" => "bitcoin",
+      "PAY_KIT_PREFLIGHT" => "maybe",
+      "PAY_KIT_MPP_EXPIRES_IN" => "soon",
+      "PAY_KIT_STABLECOINS" => " , "
+    }.each do |key, value|
+      PayKit.reset!
+      assert_raises(PayKit::ConfigurationError, key) do
+        PayKit.configure_from_env(env: {key => value})
+      end
+    end
+  end
+
   private
 
   # Replace `PayKit::Preflight.run` with a no-op spy for the duration of