如何在iOS中發送和接收Web服務請求和響應？

Question

我有一個基於Apache CXF的Web服務和Android應用程序，它使用下面的代碼向其發送請求。

現在，我想編寫一個簡單的iOS應用，該應用將相同的請求從iOS設備發送到相同的Web服務。

學習如何使用的好起點是什么

1. JSON，
2. 發送Web服務請求和
3. 從服務器接收響應

在目標C中？

SaveLocationAsyncTask.java

public class SaveLocationAsyncTask extends
        AbstractAsyncTask<SaveLocationRequest, SaveLocationResponse> implements
        ISaveLocationAsyncTask {
    private static final String SERVICE_NAME = "SaveLocation";

    public SaveLocationAsyncTask(final IWebServiceTaskHelper aHelper,
            final ILogger aLogger, final IServerUrlStorage aServerUrlStorage) {
        super(aHelper, SaveLocationResponse.class, aLogger,
                new CbResponseParser<SaveLocationResponse>(), aServerUrlStorage,
                SERVICE_NAME);
    }
}

AbstractAsyncTask.java

import android.os.AsyncTask;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.ObjectMapper;

import java.util.concurrent.ExecutionException;

public class AbstractAsyncTask<Request, Response> extends
        AsyncTask<String, String, Response> implements
        IRequestSender<Request, Response> {

    private static final String REQUEST_AS_JSON_PARAMETER_NAME = "request";
    private IWebServiceTaskHelper helper;
    private Class<Response> responseClass;
    private ILogger logger = null;
    private IResponseParser<Response> responseParser = null;
    private IServerUrlStorage serverUrlStorage;
    private String serviceName;

    public AbstractAsyncTask(final IWebServiceTaskHelper aHelper,
                             final Class<Response> aResponseClass, final ILogger aLogger,
                             final IResponseParser<Response> aResponseParser,
                             final IServerUrlStorage aServerUrlStorage, final String aServiceName) {
        helper = aHelper;
        responseClass = aResponseClass;
        logger = aLogger;
        responseParser = aResponseParser;
        serverUrlStorage = aServerUrlStorage;
        serviceName = aServiceName;
    }

    private String convertToJson(final Object aRequest) {
        final ObjectMapper mapper = new ObjectMapper();
        String json = null;

        try {
            json = mapper.writeValueAsString(aRequest);
        } catch (final JsonProcessingException exception) {
            logger.error(exception);
        }
        return json;
    }

    @Override
    protected Response doInBackground(final String... aParams) {
        logger.debug("doInBackground: " + aParams);
        return new ResponseProcessor<Response>(logger, helper, responseParser,
                responseClass).processResponse(aParams);
    }

    @Override
    public Response sendRequest(final Request aRequest)
            throws InterruptedException, ExecutionException {
        final String json = convertToJson(aRequest);
        final String url = serverUrlStorage.getServerUrl() + serviceName;

        helper.addNameValuePair(REQUEST_AS_JSON_PARAMETER_NAME, json);

        execute(url);

        return get();
    }
}

CbResponseParser.java：

import com.fasterxml.jackson.core.JsonParseException;
import com.fasterxml.jackson.databind.JsonMappingException;
import com.fasterxml.jackson.databind.ObjectMapper;

import java.io.IOException;

public class CbResponseParser<Response> implements IResponseParser<Response> {

    @Override
    public Response parseResponse(final String aResponseAsString,
                                  final Class<Response> aClass) throws IOException, JsonParseException,
            JsonMappingException {
        final ObjectMapper mapper = new ObjectMapper();
        final Response response = mapper.readValue(aResponseAsString, aClass);

        return response;
    }
}

更新1（14.06.2014 15:47 MSD）：

我已經嘗試過DJ_Lectr0的方法。 有一個問題：服務器找不到Web服務。 這是日志輸出：

WARNING: No operation matching request path "/mobilecsdemo-server/mobilecsdemo/TestMessage" is found, Relative Path: /, HTTP Method: POST, ContentType: application/json, Accept: application/json,. Please enable FINE/TRACE log level for more details.

beans.xml的片段：

<bean id="TestMessage" class="ru.mycompany.mobilecsdemo.server.services.TestMessage"/>

<jaxrs:server id="services" address="/">
    <jaxrs:serviceBeans>
        <ref bean="TestMessage"/>
    </jaxrs:serviceBeans>
</jaxrs:server>

TestMessage bean：

@Path("/TestMessage")
public class TestMessage {
    private static final Logger LOGGER = LoggerFactory.getLogger(TestMessage.class);

    @POST
    @Produces("text/plain")
    public String processTestMessage(@FormParam("request") final String aRequest)
    {
        try {
            final ObjectMapper mapper = new ObjectMapper();
            final TestMessageRequest request = mapper.readValue(aRequest,
                    TestMessageRequest.class);

            final TestMessageResponse response = new TestMessageResponse();

            response.setResponse(request.getMessage() + " - Response");

            return mapper.writeValueAsString(response);
        } catch (final JsonParseException exception) {
            LOGGER.error("getUserId", exception);
        } catch (final JsonMappingException exception) {
            LOGGER.error("getUserId", exception);
        } catch (final IOException exception) {
            LOGGER.error("getUserId", exception);
        }

        return "";
    }
}

Web服務TestMessage的URL似乎是http://AAA.BBB.CCC.DDD:8080/mobilecsdemo-server/mobilecsdemo/TestMessage 。

在iOS端發送請求的代碼：

NSDictionary *data = [NSDictionary dictionaryWithObject:@"test sending ios" forKey:@"message"];
NSError *error;
NSData *jsonData = [NSJSONSerialization dataWithJSONObject:data options:kNilOptions error:&error];

NSURL *url = [NSURL URLWithString:@"http://AAA.BBB.CCC.DDD:8080/mobilecsdemo-server/mobilecsdemo/TestMessage"];
NSMutableURLRequest *req = [NSMutableURLRequest requestWithURL:url cachePolicy:nil timeoutInterval:60];
[req setValue:@"application/json" forHTTPHeaderField:@"Accept"];
[req setValue:@"application/json" forHTTPHeaderField:@"Content-Type"];
[req setValue:[NSString stringWithFormat:@"%d", [jsonData length]] forHTTPHeaderField:@"Content-Length"];
[req setHTTPMethod:@"POST"];
[req setHTTPBody:jsonData];
NSString *retStr = [[NSString alloc] initWithData:[NSURLConnection sendSynchronousRequest:req returningResponse:nil error:nil] encoding:NSUTF8StringEncoding];

NSLog(@"Response: %@", retStr);

http://AAA.BBB.CCC.DDD:8080/mobilecsdemo-server/mobilecsdemo?_wadl顯示以下內容：

<application xmlns="http://wadl.dev.java.net/2009/02" xmlns:xs="http://www.w3.org/2001/XMLSchema">
    <grammars/>
    <resources base="http://AAA.BBB.CCC.DDD:8080/mobilecsdemo-server/mobilecsdemo/">
        <resource path="/TestMessage">
            <method name="POST">
                <request>
                    <representation mediaType="application/x-www-form-urlencoded">
                        <param name="request" style="query" type="xs:string"/>
                    </representation>
                </request>
                <response>
                    <representation mediaType="text/plain">
                        <param name="result" style="plain" type="xs:string"/>
                    </representation>
                </response>
            </method>
        </resource>
    </resources>
</application>

我試圖在iOS端將Accept和Content-Type更改為application/x-www-form-urlencoded ，但這沒有幫助。

更新2（16:36 MSD）：嘗試通過Fiddler2發送請求，此方法有效：

更新3（MSD 17:12）：這個似乎有效。

NSDictionary *data = [NSDictionary dictionaryWithObject:@"test sending ios" forKey:@"message"];
NSError *error;
NSData *jsonData = [NSJSONSerialization dataWithJSONObject:data options:kNilOptions error:&error];

NSURL *url = [NSURL URLWithString:@"http://AAA.BBB.CCC.DDD:8080/mobilecsdemo-server/mobilecsdemo/TestMessage"];
NSMutableURLRequest *req = [NSMutableURLRequest requestWithURL:url cachePolicy:nil timeoutInterval:60];


[req setValue:@"application/x-www-form-urlencoded" forHTTPHeaderField:@"Content-Type"];
[req setValue:[NSString stringWithFormat:@"%d", [jsonData length]] forHTTPHeaderField:@"Content-Length"];
[req setHTTPMethod:@"POST"];

NSString* body = @"request={\"message\":\"message content\"}";
NSData *someData = [body dataUsingEncoding:NSUTF8StringEncoding];

[req setHTTPBody:someData];
NSString *retStr = [[NSString alloc] initWithData:[NSURLConnection sendSynchronousRequest:req returningResponse:nil error:nil] encoding:NSUTF8StringEncoding];

NSLog(@"jsonData: %@", jsonData);
NSLog(@"Response: %@", retStr);

Answer 1

這將為您服務。 根據您的需要調整NSDictionary。

NSDictionary *data = [NSDictionary dictionaryWithObject:@"test sending ios" forKey:@"value1"];
NSError *error;
NSData *jsonData = [NSJSONSerialization dataWithJSONObject:data options:kNilOptions error:&error];

    NSURL *url = [NSURL URLWithString:@"http://webserveraddress"];
NSMutableURLRequest *req = [NSMutableURLRequest requestWithURL:url cachePolicy:nil timeoutInterval:60];
[req setValue:@"application/json" forHTTPHeaderField:@"Accept"];
[req setValue:@"application/json" forHTTPHeaderField:@"Content-Type"];
[req setValue:[NSString stringWithFormat:@"%d", [jsonData length]] forHTTPHeaderField:@"Content-Length"];
[req setHTTPMethod:@"POST"];
[req setHTTPBody:jsonData];
NSString *retStr = [[NSString alloc] initWithData:[NSURLConnection sendSynchronousRequest:req returningResponse:nil error:nil] encoding:NSUTF8StringEncoding];

NSURLConnection也有一個異步方法：

    [NSURLConnection sendAsynchronousRequest:req queue:[NSOperationQueue mainQueue] completionHandler:^(NSURLResponse *res3, NSData *data, NSError *connectionError) {
NSString *retStr = [[NSString alloc] initWithData:data];
}

正如Rohan Panchal的評論所提到的， AFNetworking是一個非常好的第三方庫，很好地包裝了這些方法。 我個人更喜歡裸露的NSURLConnection方法。