找不到 RestOperations bean

Question

我正在尝试为我的 Spring Boot 项目设置基本身份验证。到目前为止，我已经这样做了：

com.app.apitool.RESTConsumer 包中的

CallAPI.java

public class CallAPI {

RestTemplate restTemplate = new RestTemplate();

@Autowired
RestTemplateBuilder restTemplateBuilderObj;

@Autowired
BasicAuthSetup basicAuthObj;

@Autowired
RestOperations rest;

String endpointURL = "";

public String pingAPi() {
    HttpEntity<String> request = new HttpEntity<String>(basicAuthObj.getHeaders());

    ResponseEntity<String> response = rest.exchange(endpointURL, HttpMethod.GET, request, String.class);

    System.out.println(response.getBody());
    return response.getBody();
}
}

BasicAuthSetup.java 在 com.app.apitool.HTTPAuthSetup 包中

@Component
public class BasicAuthSetup {
private String plainCreds = "id@account1:password";
private String base64Creds = Base64.getEncoder().encodeToString(plainCreds.getBytes());

@Bean
public HttpHeaders getHeaders() {
    HttpHeaders headers = new HttpHeaders();
    headers.add("Authorization", "Basic" + base64Creds);
    System.out.println("Auth created: "+headers);
    return headers;
}                  
}

运行时出现以下异常：

---

应用程序启动失败

---

说明：

com.appd.apitool.RESTConsumer.CallAPI 中的字段 rest 需要一个 bean 输入 'org.springframework.web.client.RestOperations' 不能 找到了。

行动：

考虑定义一个 bean 类型 'org.springframework.web.client.RestOperations' 在你的配置中。

我用谷歌搜索了这个错误，我遇到了一个类似（如果不相同）的问题here，我正在遵循here 提到的解决方案。

我决定创建一个新问题的原因是因为我没有看到第一个链接所在的帖子中提到的任何解决方案。另外，我是 spring-boot 框架的新手。

com.app.apitool 包中的主要 App.java：

@SpringBootApplication
@RestController
public class App {

private static final Logger log = org.slf4j.LoggerFactory.getLogger(App.class);


@Autowired
private CallAPI callAPIobj;

public static void main(String[] args) {
    SpringApplication.run(App.class, args);
}

@RequestMapping("/api")
public String testAPI() {
    return callAPIobj.pingAPi();
}

}

Answer 1

好的，所以在您的 Maven 项目中，您的基本身份验证设置将是您配置 bean 的好地方：

BasicAuthSetup.java：

package com.app.apitool.config;

import com.fasterxml.jackson.databind.ObjectMapper;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.http.HttpEntity;
import org.springframework.http.HttpHeaders;
import org.springframework.http.converter.json.MappingJackson2HttpMessageConverter;
import org.springframework.web.client.RestTemplate;

import java.util.Base64;

@Configuration
public class BasicAuthSetup {

    private static final String plainCreds = "id@account1:password";
    private static final  String base64Creds = Base64.getEncoder().encodeToString(plainCreds.getBytes());

    @Bean
    public HttpHeaders getHeaders() {

        HttpHeaders headers = new HttpHeaders();
        headers.add("Authorization", "Basic" + base64Creds);

        return headers;
    }

    @Bean
    public RestTemplate restTemplate() {

        RestTemplate restTemplate = new RestTemplate();
        MappingJackson2HttpMessageConverter converter = new MappingJackson2HttpMessageConverter();
        converter.setObjectMapper(new ObjectMapper());
        restTemplate.getMessageConverters().add(converter);

        return restTemplate;
    }

    @Bean
    public HttpEntity<String> stringHttpEntity() {
        return new HttpEntity<>(getHeaders());
    }
}

然后，在 /src/main/java 下的相应包中创建一个测试类，如下所示：

CallAPITest.java：

package com.app.apitool;

import com.app.apitool.config.BasicAuthSetup;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.HttpEntity;
import org.springframework.http.HttpMethod;
import org.springframework.http.ResponseEntity;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
import org.springframework.web.client.RestOperations;

import static org.junit.Assert.assertNotNull;

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(classes = BasicAuthSetup.class)
public class CallAPITest {

    private static final String endpointURL = "";

    @Autowired
    private RestOperations rest;

    @Autowired
    private HttpEntity<String> stringHttpEntity;

    @Test
    public void pingAPi() {

        ResponseEntity<String> response = rest.exchange(endpointURL, HttpMethod.GET, stringHttpEntity, String.class);

        System.out.println(response.getBody());

        final String responseBody = response.getBody();

        assertNotNull(responseBody);
    }
}

以下是您在 Maven pom.xml 中需要的依赖项（根据需要更改版本）：

<properties>
    <jackson.version>2.9.6</jackson.version>
    <spring.version>4.3.5.RELEASE</spring.version>
</properties>

<dependencies>
    <dependency>
        <groupId>com.fasterxml.jackson.core</groupId>
        <artifactId>jackson-core</artifactId>
        <version>${jackson.version}</version>
    </dependency>
    <dependency>
        <groupId>com.fasterxml.jackson.core</groupId>
        <artifactId>jackson-databind</artifactId>
        <version>${jackson.version}</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-context</artifactId>
        <version>${spring.version}</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-context-support</artifactId>
        <version>${spring.version}</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-test</artifactId>
        <version>${spring.version}</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-web</artifactId>
        <version>${spring.version}</version>
    </dependency>
    <dependency>
        <groupId>junit</groupId>
        <artifactId>junit</artifactId>
        <version>4.12</version>
        <scope>test</scope>
    </dependency>
</dependencies>