Question

我有一个外部API，它使用DELETE和body（JSON）。我使用Postman REST Client并使用请求体完成删除，它工作正常。我正在尝试使用方法自动执行此功能。

我尝试了类似的GET，POST和PUT的HttpURLConnection。但我不确定如何将DELETE与请求体一起使用。

我已经检查过StackOverflow并且看不到这个问题，但它们是非常古老的答案。

有人可以帮忙吗？我正在使用spring框架。

Answer 1

我使用org.apache.http来完成这项工作。

@NotThreadSafe
class HttpDeleteWithBody extends HttpEntityEnclosingRequestBase {
    public static final String METHOD_NAME = "DELETE";

    public String getMethod() {
        return METHOD_NAME;
    }

    public HttpDeleteWithBody(final String uri) {
        super();
        setURI(URI.create(uri));
    }

    public HttpDeleteWithBody(final URI uri) {
        super();
        setURI(uri);
    }

    public HttpDeleteWithBody() {
        super();
    }
}



public String[] sendDelete(String URL, String PARAMS, String header) throws IOException {
    String[] restResponse = new String[2];
        CloseableHttpClient httpclient = HttpClients.createDefault();

        HttpDeleteWithBody httpDelete = new HttpDeleteWithBody(URL);
        StringEntity input = new StringEntity(PARAMS, ContentType.APPLICATION_JSON);
        httpDelete.addHeader("header", header);
        httpDelete.setEntity(input);  

        Header requestHeaders[] = httpDelete.getAllHeaders();
        CloseableHttpResponse response = httpclient.execute(httpDelete);
        restResponse[0] = Integer.toString((response.getStatusLine().getStatusCode()));
        restResponse[1] = EntityUtils.toString(response.getEntity());    
        return restResponse;
    }
}

Answer 2

如果您使用的是Spring，则可以使用RestTemplate生成客户端请求。在这种情况下，您可以使用RestTemplate.exchange并提供url，http方法和请求正文。像（没有经过测试，但你明白了）：

RestTemplate restTemplate = new RestTemplate();
HttpEntity<Foo> request = new HttpEntity<>(new Foo("bar"));
restTemplate.exchange(url, HttpMethod.DELETE, request, null);

Answer 3

这段代码对我有用： -

您可以通过httpCon.setRequestProperty
您可以通过httpCon.setRequestMethod

将json主体写入OutputStreamWriter，在我的示例中，我使用Jackson ObjectMapper将Java对象转换为json

URL url = new URL("http://localhost:8080/greeting");
HttpURLConnection httpCon = (HttpURLConnection) url.openConnection();
httpCon.setDoOutput(true);
httpCon.setRequestProperty(
                "Content-Type", "application/json");
httpCon.setRequestMethod("DELETE");
OutputStreamWriter out = new OutputStreamWriter(
                httpCon.getOutputStream());
ObjectMapper objectMapper = new ObjectMapper();
out.write(objectMapper.writeValueAsString(new Greeting("foo")));
out.close();
httpCon.connect();

Answer 4

仅仅覆盖getMethod()类的HttpPost方法并不容易吗？

private String curl(                    // Return JSON String
        String method,                  // HTTP method, for this example the method parameter should be "DELETE", but it could be PUT, POST, or GET.
        String url,                     // Target URL  
        String path,                    // API Path
        Map<String, Object> queryParams,// Query map forms URI
        Map<String, Object> postParams) // Post Map serialized to JSON and is put in the header
        throws Error,               // when API returns an error
        ConnectionClosedException       // when we cannot contact the API
{
   HttpClient client = HttpClients.custom()
            .setDefaultRequestConfig(
                    RequestConfig.custom()
                            .setCookieSpec(CookieSpecs.STANDARD)
                            .build()
            ).build();


    HttpPost req = new HttpPost(){
        @Override
        public String getMethod() {
            // lets override the getMethod since it is the only
            // thing that differs between each of the subclasses
            // of HttpEntityEnclosingRequestBase. Let's just return
            // our method parameter in the curl method signature.
            return method;
        }
    };

    // set headers
    req.setHeader("user-agent", "Apache");
    req.setHeader("Content-type", "application/json");
    req.setHeader("Accept", "application/json");

    try {
        // prepare base url
        URIBuilder uriBuilder = new URIBuilder(url + path);

        if (method.equals("GET")){
            queryParams.forEach((k, v)-> uriBuilder.addParameter(k, v.toString()));
        }else{
            String postPramsJson = new Gson().toJson(postParams);
            req.setEntity(new StringEntity(postPramsJson));
        }

        // set the uri
        req.setURI(uriBuilder.build().normalize());

        // execute the query
        final HttpResponse response = client.execute(req);

        //
        if (response.getEntity() != null) {
            if(response.getStatusLine().getStatusCode() == 200){
                 return EntityUtils.toString(response.getEntity());
            }
            logger.error("ERROR: Response code " + response.getStatusLine().getStatusCode() +
                     ", respnse: " + EntityUtils.toString(responseEntry));
        }
        throw new Error("HTTP Error");
    } catch (Exception e) {
        logger.error("Connection error", e);
        throw new ConnectionClosedException("Cannot connect to " + url);
    }
}

关键是不必在你的包中添加另一个类......为什么不在getMethod()的已经子类对象中覆盖HttpEntityEnclosingRequestBase？

带有Request Body的Java HTTP DELETE

4 个答案: