feat: add StripeClient.create_price for metered billing

config/test.exs

@@ -94,4 +94,6 @@ config :towerops,
   # Reduce debounce delay in tests for faster test execution (50ms vs 500ms in prod)
   agent_channel_debounce_ms: 50,
   # Reduce device deletion delay for faster tests (10ms vs 500ms in prod)
-  device_deletion_delay_ms: 10
+  device_deletion_delay_ms: 10,
+  # Stripe test configuration
+  stripe_product_id: "prod_test"

lib/towerops/billing/stripe_client.ex

@@ -125,6 +125,33 @@ defmodule Towerops.Billing.StripeClient do
     end
   end
 
+  # Price Management
+
+  @doc """
+  Create a new Price object for metered billing.
+
+  Returns {:ok, price_object} or {:error, reason}.
+  """
+  def create_price(unit_amount_decimal) when is_binary(unit_amount_decimal) do
+    params = %{
+      product: stripe_product_id(),
+      currency: "usd",
+      unit_amount_decimal: unit_amount_decimal,
+      recurring: %{
+        interval: "month",
+        usage_type: "metered",
+        aggregate_usage: "max"
+      },
+      billing_scheme: "per_unit",
+      metadata: %{
+        created_by: "towerops_admin_ui",
+        created_at: DateTime.to_iso8601(DateTime.utc_now())
+      }
+    }
+
+    post("/v1/prices", params)
+  end
+
   # HTTP Request Helpers
 
   defp get(path) do
@@ -255,4 +282,8 @@ defmodule Towerops.Billing.StripeClient do
   defp stripe_price_id do
     Application.fetch_env!(:towerops, :stripe_price_id)
   end
+
+  defp stripe_product_id do
+    Application.fetch_env!(:towerops, :stripe_product_id)
+  end
 end

test/towerops/billing/stripe_client_test.exs

@@ -315,4 +315,49 @@ defmodule Towerops.Billing.StripeClientTest do
                StripeClient.create_customer(organization)
     end
   end
+
+  describe "create_price/1" do
+    test "creates metered billing price at specified amount" do
+      Req.Test.stub(StripeClient, fn conn ->
+        assert conn.method == "POST"
+        assert conn.request_path == "/v1/prices"
+
+        # Verify form params
+        {:ok, body, conn} = Plug.Conn.read_body(conn)
+        params = URI.decode_query(body)
+
+        assert params["unit_amount_decimal"] == "2.50"
+        assert params["currency"] == "usd"
+        assert params["recurring[interval]"] == "month"
+        assert params["recurring[usage_type]"] == "metered"
+        assert params["recurring[aggregate_usage]"] == "max"
+        assert params["billing_scheme"] == "per_unit"
+
+        conn
+        |> Plug.Conn.put_resp_content_type("application/json")
+        |> Plug.Conn.send_resp(
+          200,
+          Jason.encode!(%{
+            "id" => "price_test123",
+            "object" => "price",
+            "unit_amount_decimal" => "2.50"
+          })
+        )
+      end)
+
+      assert {:ok, %{"id" => "price_test123"}} = StripeClient.create_price("2.50")
+    end
+
+    test "returns error on API failure" do
+      Req.Test.stub(StripeClient, fn conn ->
+        error = %{"error" => %{"message" => "Invalid amount"}}
+
+        conn
+        |> Plug.Conn.put_resp_content_type("application/json")
+        |> Plug.Conn.send_resp(400, Jason.encode!(error))
+      end)
+
+      assert {:error, {:bad_request, "Invalid amount"}} = StripeClient.create_price("invalid")
+    end
+  end
 end