Java 如何使用Swagger codegen开发一个简单的REST客户端？

我正在学习Swagger以及如何使用Swagger codegen生成REST客户端。我知道如何使用Swagger编写文档，也知道如何使用Swagger生成简单的REST服务器，但我不知道如何使用Swagger codegen生成简单的REST客户端

例如，我有一个简单的应用程序，它是一个REST服务器，我想生成REST客户端。我能和斯威格·科德根一起做吗

REST服务器的控制器：

package com.dgs.spring.springbootswagger.controller;

import io.swagger.annotations.Api;
import io.swagger.annotations.ApiOperation;
import io.swagger.annotations.ApiParam;
import io.swagger.annotations.ApiResponse;
import io.swagger.annotations.ApiResponses;

@RestController
@RequestMapping("/api/v1")
@Api(value = "Employee Management System", description = "Operations pertaining to employee in Employee Management System")
public class EmployeeController {

     @Autowired
     private EmployeeRepository employeeRepository;

        @ApiOperation(value = "View a list of available employees", response = List.class)
        @ApiResponses(value = {
            @ApiResponse(code = 200, message = "Successfully retrieved list"),
            @ApiResponse(code = 401, message = "You are not authorized to view the resource"),
            @ApiResponse(code = 403, message = "Accessing the resource you were trying to reach is forbidden"),
            @ApiResponse(code = 404, message = "The resource you were trying to reach is not found")
        })
     @GetMapping("/employees")
     public List<Employee> getAllEmployees() {
         return employeeRepository.findAll();
     }

     @ApiOperation(value = "Get an employee by Id")   
     @GetMapping("/employees/{id}")
     public ResponseEntity<Employee> getEmployeeById(
             @ApiParam(value = "Employee id from which employee object will retrieve", required = true) @PathVariable(value = "id") Long employeeId)
             throws ResourceNotFoundException {

          Employee employee = employeeRepository.findById(employeeId)
            .orElseThrow(() -> new ResourceNotFoundException("Employee not found for this id :: " + employeeId));

          return ResponseEntity.ok().body(employee);
     }

     @ApiOperation(value = "Add an employee")
     @PostMapping("/employees")
     public Employee createEmployee(
             @ApiParam(value = "Employee object store in database table", required = true) @Valid @RequestBody Employee employee) {
         return employeeRepository.save(employee);
     }

     @ApiOperation(value = "Update an employee")
     @PutMapping("/employees/{id}")
     public ResponseEntity<Employee> updateEmployee(
             @ApiParam(value = "Employee Id to update employee object", required = true) @PathVariable(value = "id") Long employeeId,
             @ApiParam(value = "Update employee object", required = true) @Valid @RequestBody Employee employeeDetails) throws ResourceNotFoundException {

          Employee employee = employeeRepository.findById(employeeId)
            .orElseThrow(() -> new ResourceNotFoundException("Employee not found for this id :: " + employeeId));

          employee.setEmail(employeeDetails.getEmail());
          employee.setLastName(employeeDetails.getLastName());
          employee.setFirstName(employeeDetails.getFirstName());
          final Employee updatedEmployee = employeeRepository.save(employee);

          return ResponseEntity.ok(updatedEmployee);
     }

     @ApiOperation(value = "Delete an employee")
     @DeleteMapping("/employees/{id}")
     public Map<String, Boolean> deleteEmployee(
             @ApiParam(value = "Employee Id from which employee object will delete from database table", required = true) @PathVariable(value = "id") Long employeeId)
       throws ResourceNotFoundException {

      Employee employee = employeeRepository.findById(employeeId)
        .orElseThrow(() -> new ResourceNotFoundException("Employee not found for this id :: " + employeeId));

      employeeRepository.delete(employee);
      Map<String, Boolean> response = new HashMap<>();
      response.put("deleted", Boolean.TRUE);

      return response;
     }
}

雇主客户：

package com.dgs.restclient.integration;

@Component
public class EmployeeRestClientImpl implements EmployeeRestClient {

    private static final String EMPLOYEE_REST_URL = 
            "http://localhost:8080/api/v1/employees/";

    @Override
    public Employee findEmployee(Long id) {

        RestTemplate restTemplate = new RestTemplate();
        Employee employee = restTemplate
                .getForObject(EMPLOYEE_REST_URL + id, Employee.class);

        return employee;
    }

    @Override
    public Employee updateEmployee(EmployeeUpdateRequest request) {

        RestTemplate restTemplate = new RestTemplate();
        restTemplate
                .put(EMPLOYEE_REST_URL + request.getId(), request, Employee.class); 

        Employee employee = restTemplate
                .getForObject(EMPLOYEE_REST_URL + request.getId(), Employee.class);

        return employee;
    }

}

这个REST客户机是由我开发的，我想知道我是否可以用Swagger codegen开发这个REST客户机，以及如何开发？我需要在pom.xml中添加swagger codegen maven插件吗？我听说添加了这个插件和一个yml文件，Swagger将创建REST客户端。任何反馈都将不胜感激

更新：

你的问题在另一篇帖子中得到了回答。看看：

供参考使用命令行的简单方法： 贝尔东有一个很好的教程：

例如。 执行命令：

java -jar swagger-codegen-cli.jar generate \
  -i http://mydomain/v2/swagger.json \
  --api-package com.mypackage.api \
  --model-package com.mypackage.model \
  --invoker-package com.mypackage.invoker \
  --group-id com.mygroup \
  --artifact-id spring-swagger-codegen-api-client \
  --artifact-version 0.0.1-SNAPSHOT \
  -l java \
  --library resttemplate \
  -o spring-swagger-codegen-api-client

Swagger Codegen支持以下客户端实现：

球衣1+杰克逊

球衣2+杰克逊

假装+杰克逊

OkHttp+Gson

改造2/OkHttp+Gson

SpringRestTemplate+Jackson

Resteasy+Jackson

另外，正如您所看到的，rest客户机是根据swagger规范定义生成的，它是用“-i”参数定义的。

是。您可以使用生成REST客户端。但在此之前，您需要用YAML或JSON描述restapi，这主要是因为

swagger-codegen-maven-plugin

只能从本规范中编写的文件生成REST客户端

其他答案假设您需要手动编写规范，而我的解决方案进一步从REST控制器源代码自动生成规范

最新的OpenAPI版本是3.0。但是根据您导入的swagger注释包，您使用的是2.0版（或之前的版本）。因此，我的解决方案假设您使用的是OpenAPI 2.0

生成开放式API规范

首先，可以使用从RestController源代码生成OpenAPI规范。它主要分析

中指定的

@RestController

类中注释的Swagger注释，并将OpenAPI规范转储到

/src/main/resources/Swagger.json

：

<plugin>
    <groupId>com.github.kongchen</groupId>
    <artifactId>swagger-maven-plugin</artifactId>
    <version>3.1.5</version>
    <configuration>
        <apiSources>
            <apiSource>
                <springmvc>true</springmvc>
                <locations>
                    <location>com.dgs.spring.springbootswagger.controller.EmployeeController</location>
                    <location>com.dgs.spring.springbootswagger.controller.FooController</location>
                </locations>
                <schemes>
                    <scheme>http</scheme>
                </schemes>
                <host>127.0.0.1:8080</host>
                <basePath>/</basePath>
                <info>
                    <title>My API</title>
                    <version>1.1.1</version>
                </info>
                <swaggerDirectory>${basedir}/src/main/resources/</swaggerDirectory>
            </apiSource>
        </apiSources>
    </configuration>
    <executions>
        <execution>
            <goals>
                <goal>generate</goal>
            </goals>
        </execution>
    </executions>
</plugin>

生成Rest客户端

生成

swagger.json

后，您可以将其复制并粘贴到客户端项目（例如/src/main/resources/swagger.json）。然后，我们可以使用

swagger-codegen-maven-plugin

生成HTTP客户端

默认情况下，它将生成包含测试用例和其他文档内容的。但是我想要的只是HttpClient的源代码，没有其他东西。经过多次尝试和错误，我决定采用以下配置：

<plugin>
    <groupId>io.swagger</groupId>
    <artifactId>swagger-codegen-maven-plugin</artifactId>
    <version>2.4.7</version>
    <executions>
        <execution>
            <goals>
                <goal>generate</goal>
            </goals>
            <configuration>
                <inputSpec>${basedir}/src/main/resources/swagger.json</inputSpec>
                <language>java</language>
                <library>resttemplate</library>
                <output>${project.basedir}/target/generated-sources/</output>

                <apiPackage>com.example.demo.restclient.api</apiPackage>
                <modelPackage>com.example.demo.restclient.model</modelPackage>
                <invokerPackage>com.example.demo.restclient</invokerPackage>

                <generateApiTests>false</generateApiTests>
                <generateModelTests>false</generateModelTests>
                <generateApiDocumentation>false</generateApiDocumentation>
                <generateModelDocumentation>false</generateModelDocumentation>
                <configOptions>
                    <dateLibrary>java8</dateLibrary>
                    <sourceFolder>restclient</sourceFolder>
                </configOptions>
            </configuration>
        </execution>
    </executions>
</plugin>

要使用生成的HTTP客户端，请执行以下操作：

ApiClient apiClient = new ApiClient();

//Override the default API base path configured in Maven
apiClient.setBasePath("http://api.example.com/api");

EmployeeManagementSystemApi api = new EmployeeManagementSystemApi(apiClient);
api.getEmployeeById(1l);

---

注:

• 如果在使用java8+生成时遇到

  javax/xml/bind/annotation/XmlRootElement

  异常，可能需要参考

---

只需添加一个招摇过市的插件并不会生成rest客户端，您需要按照以下步骤操作

用YAML格式写下规范。根据规范结果，将生成。将规范另存为YAML文件。它将保存为swagger.yaml 按照教程进行操作：

1）要创建您的招摇过市文档，我将使用“招摇过市Petstore”作为示例

2） 现在选择File，导入File并上传下载的swagger.json文件

3） 打开

4） 使用以下步骤：

i） 将存储库克隆到磁盘git Clone

ii）运行mvn清洁包

iii）将swagger-codegen-cli.jar文件从目标文件夹复制到计算机上的本地驱动器

iv）接下来执行以下命令以生成客户端：

     java -jar swagger-codegen-cli.jar -i <json_file> -l python -o my_client

Swagger Codegen是一个开源项目，它允许生成 API客户端库（SDK生成）、服务器存根和文档 从OpenAPI规范自动生成。斯威格·科德根是 可在GitHub存储库中下载，也可以生成 对于集成API中定义的任何新的或现有的OpenAPI 昂首阔步的枢纽平台。SwaggerHub提供了Swagger编辑器、UI和 Codegen工具以集成API设计和 文档，为使用Swagger（OpenAPI）的API团队构建 规格

有Maven和Gradle等构建工具的插件，因为已经给出了一些答案，所以这里没有添加

大摇大摆的端点 假设您的应用程序的Swagger端点可以在以下位置访问：

测试Swagger 2.0 JSON API文档

（如果尚未设置名为

employee

的组）

测试招摇过市用户界面

下载Swagger Codegen可执行文件 您可以从Maven中央存储库下载

生成客户端代码 现在您有了Swagger Codegen JAR，您可以通过执行以下命令来生成REST客户端：

java -jar swagger-codegen-cli-2.4.7.jar generate \
  -i http://localhost:8080/v2/api-docs?group=employee \
  -l java \
  -o swagger-codegen-client

如果不招摇,

java -jar swagger-codegen-cli-2.4.7.jar generate \
  -i http://localhost:8080/v2/api-docs \
  -l java \
  -o swagger-codegen-client

选择权 尽管Swagger Codegen CLI附带了许多选项，但我们使用的选项对于 生成客户端代码

• -i

  指向应用程序的

  Swagger api文档的URL

• -l

  客户端的编程语言，在本例中为

  java

• -o

  生成的客户端代码的输出文件夹

执行上一个生成代码的命令后，应注意终端上的以下消息：

[main] INFO io.swagger.parser.Swagger20Parser - reading from http://localhost:8080/v2/api-docs?group=employee
[main] WARN io.swagger.codegen.ignore.CodegenIgnoreProcessor - Output directory does not exist, or is inaccessible. No file (.swagger-codegen-ignore) will be evaluated.
[main] INFO io.swagger.codegen.AbstractGenerator - writing file swagger-codegen-client/src/main/java/io/swagger/client/model/Employee.java
[main] INFO io.swagger.codegen.AbstractGenerator - writing file swagger-codegen-client/docs/Employee.md
[main] INFO io.swagger.codegen.AbstractGenerator - writing file swagger-codegen-client/src/main/java/io/swagger/client/api/EmployeeControllerApi.java
...
[main] INFO io.swagger.codegen.AbstractGenerator - writing file swagger-codegen-client/src/main/java/io/swagger/client/ApiClient.java
...

REST客户端项目 一旦代码生成

 -i Specifies the path to the input file. This can be a URL

 -l Specifies the programming language for the client

 -o Specifies the output directory where the generate code should be located

java -jar swagger-codegen-cli-2.4.7.jar generate \
  -i http://localhost:8080/v2/api-docs?group=employee \
  -l java \
  -o swagger-codegen-client

java -jar swagger-codegen-cli-2.4.7.jar generate \
  -i http://localhost:8080/v2/api-docs \
  -l java \
  -o swagger-codegen-client

[main] INFO io.swagger.parser.Swagger20Parser - reading from http://localhost:8080/v2/api-docs?group=employee
[main] WARN io.swagger.codegen.ignore.CodegenIgnoreProcessor - Output directory does not exist, or is inaccessible. No file (.swagger-codegen-ignore) will be evaluated.
[main] INFO io.swagger.codegen.AbstractGenerator - writing file swagger-codegen-client/src/main/java/io/swagger/client/model/Employee.java
[main] INFO io.swagger.codegen.AbstractGenerator - writing file swagger-codegen-client/docs/Employee.md
[main] INFO io.swagger.codegen.AbstractGenerator - writing file swagger-codegen-client/src/main/java/io/swagger/client/api/EmployeeControllerApi.java
...
[main] INFO io.swagger.codegen.AbstractGenerator - writing file swagger-codegen-client/src/main/java/io/swagger/client/ApiClient.java
...

__ swagger-codegen-client
  |__ README.md
  |__ build.gradle
  |__ build.sbt
  |__ docs
  |__ git_push.sh
  |__ gradle
  |__ gradle.properties
  |__ gradlew
  |__ gradlew.bat
  |__ pom.xml
  |__ settings.gradle
  |__ src
     |__ main
        |__ java
          |__ io.swagger.client.api
             |__ EmployeeControllerApi.java
     |__ test
        |__ java
          |__ io.swagger.client.api
             |__ EmployeeControllerApiTest.java

    <dependency>
        <groupId>javax.xml.bind</groupId>
        <artifactId>jaxb-api</artifactId>
        <version>2.3.0</version>
    </dependency>
    <dependency>
        <groupId>com.sun.xml.bind</groupId>
        <artifactId>jaxb-core</artifactId>
        <version>2.3.0</version>
    </dependency>
    <dependency>
        <groupId>com.sun.xml.bind</groupId>
        <artifactId>jaxb-impl</artifactId>
        <version>2.3.0</version>
    </dependency>

    <dependency>
        <groupId>javax.annotation</groupId>
        <artifactId>javax.annotation-api</artifactId>
        <version>1.3.2</version>
    </dependency>

Employee employee = new Employee();
employee.setId(3L);
employee.setFirstName("Sam");
employee.setLastName("Fox");
employee.setEmail("sfox@gmail.com");

EmployeeControllerApi api = new EmployeeControllerApi();
Employee response = api.createEmployeeUsingPOST(employee);
System.out.println(response);

class Employee {
    email: sfox@gmail.com
    firstName: Sam
    id: 3
    lastName: Fox
}