使用 Camel 的 REST 服务调用需要首先调用身份验证 api

Question

Camel 必须调用 REST 服务进行某些集成，但是，REST 服务有一个身份验证 api (POST api)，需要首先调用它来获取令牌，然后必须调用嵌入令牌的其他后续 api 调用在 HTTP 请求的标头中。

Spring Restemplate 或 apache camel 是否有一些 api 来支持相同的功能？

Answer 1

遵循@gusto2 方法，它几乎可以正常工作。

所以，我创建了两条路由 --> 第一个是基于定时器的，如下所示，它生成令牌，定期刷新它（因为路由是基于定时器的）并将令牌存储在局部变量中以供某些人重用其他路线。

@Component
public class RestTokenProducerRoute extends RouteBuilder {

    private String refreshedToken;

    @Override
    public void configure() throws Exception {

        restConfiguration().producerComponent("http4");

        from("timer://test?period=1200000") //called every 20 mins
                    .process(
                            exchange -> exchange.getIn().setBody(
                                    new UserKeyRequest("apiuser", "password")))
                    .marshal(userKeyRequestJacksonFormat) //convert it to JSON
                    .setHeader(Exchange.HTTP_METHOD, constant("POST"))
                    .setHeader(Exchange.CONTENT_TYPE, constant("application/json"))
                    .to("http4://localhost:8085/Service/Token")
                    .unmarshal(userKeyResponseJacksonFormat)
                    .process(new Processor() {
                        public void process(Exchange exchange) throws Exception {   
                            UserKeyResponse response= exchange.getIn().getBody(
                                    UserKeyResponse.class); //get the response object
                            System.out.println(response + "========>>>>>>" +  
                                    response.getResult());
                            setRefreshedToken(response.getResult()); //store the token in some object
                        }
                    }).log("${body}");
        }

        public String getRefreshedToken() {
            return refreshedToken;
        }

        public void setRefreshedToken(String refreshedToken) {
            this.refreshedToken = refreshedToken;
        }
}

第二个路由可以调用后续的api，这些api将使用第一个路由生成的令牌，它会是这样的。必须添加错误处理场景，其中令牌可能无效或过期。但我想这将是另一个需要解决的问题。

@Component
public class RestTokenUserOnboardRoute extends RouteBuilder  {

    private JacksonDataFormat OtherDomainUserRequestJacksonFormat = new JacksonDataFormat(
            OtherDomainUserRequest.class);
    private JacksonDataFormat OtherDomainUserResponseJacksonFormat = new JacksonDataFormat(
            OtherDomainUserResponse.class);
    @Override
    public void configure() throws Exception {

        restConfiguration().producerComponent("http4");

        //This route is subscribed to a Salesforce topic, which gets invoked when there is any new messages in the topic.
        from("salesforce:CamelTestTopic?sObjectName=MyUser__c&sObjectClass="+MyUser__c.class.getName()))
            .convertBodyTo(OtherDomainUserRequest.class)
            .marshal(OtherDomainUserRequestJacksonFormat).log("${body}")
            .setHeader(Exchange.HTTP_METHOD, constant("POST"))
            .setHeader(Exchange.CONTENT_TYPE, constant("application/json"))
            .log("The token being passed is ==> ${bean:tokenObj?method=getRefreshedToken}")
            .setHeader("Authorization", simple("${bean:tokenObj?method=getRefreshedToken}"))
            .to("http4://localhost:8085/Service/DomainUser")
            .unmarshal(OtherDomainUserResponseJacksonFormat)
            .process(new Processor() {
            public void process(Exchange exchange) throws Exception {
                    OtherDomainUserResponse response = exchange.getIn().getBody(
                            OtherDomainUserResponse.class);
                            System.out.println(response + "==================>>>>>> " + response.getStatusCode());
                        }
            }).log("${body}");
    }
}

所以，这里的令牌是从tokenObj bean 中消耗的（RestTokenProducerRoute 的实例，它定义了方法getRefreshedToken()。它返回存储的令牌。

不用说，您已经在 camelcontext 注册表中设置了 bean 以及其他设置（如组件、路由等），如下所示。在我的情况下，如下所示。

@Autowired
public RestTokenUserOnboardRoute userOnboardRoute;
@Autowired
public RestTokenProducerRoute serviceTokenProducerRoute;

@Autowired
private RestTokenProducerRoute tokenObj;

@Override
protected CamelContext createCamelContext() throws Exception {
    SimpleRegistry registry = new SimpleRegistry(); 
    registry.put("tokenObj", tokenObj); //the tokenObj bean,which can be used anywhere in the camelcontext
    SpringCamelContext camelContext = new SpringCamelContext();
    camelContext.setRegistry(registry); //add the registry
    camelContext.setApplicationContext(getApplicationContext());
    camelContext.addComponent("salesforce", salesforceComponent());
    camelContext.getTypeConverterRegistry().addTypeConverter(DomainUserRequest.class, MyUser__c.class, new MyTypeConverter());
    camelContext.addRoutes(route()); //Some other route
    camelContext.addRoutes(serviceTokenProducerRoute); //Token producer Route
    camelContext.addRoutes(userOnboardRoute); //Subsequent API call route
    camelContext.start();
    return camelContext;
}

这解决了我动态设置令牌的问题，其中令牌是由于执行其他路由而产生的。