如何在wiremock-pact-generator中添加Pact场景状态（provider_state）

我们使用wiremock-pact-generator生成Pact合约文件，但未找到该库处理场景状态的方式。此前通过pactdslwithprovider可以设置状态，现在希望用wiremock-pact-generator实现同样功能。

已为MockServer添加wiremock-pact-generation监听器，相关代码如下：

@BeforeAll
public static void setup() {
  mockServer =
      new WireMockServer(options().port(1080).extensions(new ResponseTemplateTransformer(true)));
  mockServer.addMockServiceRequestListener(
      WireMockPactGenerator.builder("product-service-consumer", "producte-service-provider").build());
  mockServer.start();
}

当前使用的WireMock stub配置：

{
  "request" : {
    "urlPathPattern" : "/products/1001",
    "method" : "GET"
  },
  "response" : {
    "status" : 200,
    "body" : "{\"productId\":1001,\"name\": \"Dell Laptop\",\"description\": \"Warranty expiring soon\"}",
    "headers" : {
      "X-Application-Context" : "application:-1",
      "Content-Type" : "application/json"
    },
    "transformers" : [ "response-template" ]

  }
}

生成的Pact合约文件中interactions缺少provider_state字段，希望添加"provider_state": "Fetch Product for Id 1001"，请问该如何配置？

wiremock-pact-generator支持通过WireMock stub的**元数据（metadata）**来指定provider状态，具体配置方式如下：

1. 修改JSON格式的Stub配置 #

在stub的根节点添加metadata字段，指定pact相关配置，其中包含providerState：

{
  "request" : {
    "urlPathPattern" : "/products/1001",
    "method" : "GET"
  },
  "response" : {
    "status" : 200,
    "body" : "{\"productId\":1001,\"name\": \"Dell Laptop\",\"description\": \"Warranty expiring soon\"}",
    "headers" : {
      "X-Application-Context" : "application:-1",
      "Content-Type" : "application/json"
    },
    "transformers" : [ "response-template" ]
  },
  "metadata": {
    "pact": {
      "providerState": "Fetch Product for Id 1001"
    }
  }
}

2. 若使用Java代码定义Stub #

如果是通过Java API创建WireMock stub，可通过withMetadata()方法添加对应配置：

stubFor(get(urlPathEqualTo("/products/1001"))
    .willReturn(aResponse()
        .withStatus(200)
        .withHeader("Content-Type", "application/json")
        .withBody("{\"productId\":1001,\"name\": \"Dell Laptop\",\"description\": \"Warranty expiring soon\"}")
        .withTransformer("response-template"))
    .withMetadata(Map.of(
        "pact", Map.of("providerState", "Fetch Product for Id 1001")
    )));

配置完成后，重新运行测试，生成的Pact合约文件中对应的interaction就会包含provider_state字段。

内容的提问来源于stack exchange，提问作者Gurubabu