如何使用从 apache 骆驼中的另一个 api 获得的参数调用 api？

Question

我通过 apache 调用了 REST api 并对其进行了反序列化。 我需要调用另一个 API，其编号是我从调用前一个 api 时收到的参数。 我是通过以下方式做到的 -

    public Collection<String> nos;
    
     from("direct:further").tracing()
            .log("body: " + body().toString())
            .setBody().constant(null)
            .setHeader("CamelHttpMethod")
            .simple("GET")
            .setHeader("Authorization")
            .simple("Bearer "+"${header.jwt}")
            .to("https://call/api/that/returns/numbers")
            .choice()
            .when().simple("${header.CamelHttpResponseCode} == 200").unmarshal().json(JsonLibrary.Jackson, Abc.class)
    .process(
                ex->{
                  Quantity quantity = ex.getIn().getBody(Abc.class);
                  List<Variations> variationsList = Arrays.stream(quantity.getResources().getVariations()).toList();
                  nos=variationsList.stream().map(Variations::getNo).collect(
                      Collectors.toList());
     nos.forEach(s -> { //Since nos is a collection of String I would like to iterate through it
         
          String url="https://call/another/api/with/number"+"?"+s;//the link with the number as the parameter 
                    from("direct:start")   //This is not working. I not able to call the url
                        .setHeader("CamelHttpHeader")
                          .simple("GET")
                          .setHeader("Authorization")
                          .simple("Bearer "+"${header.jwt}")
                          .log("I did call the numbers") //This is also not getting printed
                        .to(url);
    });
     }).log("I am out of the loop" + body())
            .otherwise()
            .log("Error!!!");

我无法使用我收到的号码呼叫另一个 api，而我收到的号码是呼叫第一个 api。 我该怎么做？ 我也试着这样称呼它

                from("rest:get:"+url).tracing()
                    .setHeader("CamelHttpHeader")
                    .simple("GET")
                    .setHeader("Authorization")
                    .simple("Bearer "+"${header.jwt}")
                    .log("I did call the numbers").to(url);

但不幸的是，上面的代码在循环内也不起作用。 我在方法定义之外声明了集合号。 我应该如何从 nos 集合中存储的号码中调用另一个 API ？ 我应该在 lambda function 外面还是里面打电话给另一个 Api ？

Answer 1

与其尝试在处理器内定义新路由，不如将数字集合存储到正文并使用 split 调用动态生产者端点toD ，它可以使用简单的语言来构造带有来自正文、标题、属性等的值的 uri。

如果您以后需要收集所有回复到说列表，您可以创建自定义AggregationStrategy或使用灵活的。

Camel 3.18.2 使用单元测试的简单示例

package com.example;

import java.util.ArrayList;

import org.apache.camel.AggregationStrategy;
import org.apache.camel.Exchange;
import org.apache.camel.RoutesBuilder;
import org.apache.camel.builder.AdviceWith;
import org.apache.camel.builder.AggregationStrategies;
import org.apache.camel.builder.RouteBuilder;
import org.apache.camel.component.mock.MockEndpoint;
import org.apache.camel.model.dataformat.JsonLibrary;
import org.apache.camel.test.junit5.CamelTestSupport;
import org.junit.jupiter.api.Test;


public class NumbersAPITests extends CamelTestSupport {
    
    @Test
    public void testAPILogic() throws Exception {
        
        replaceHttpEndpointWithSimpleResponse("requestNumbersFromAPI", 
            "[1,2,3,4,5]");
        replaceHttpEndpointWithSimpleResponse("requestDataWithIdFromAPI", 
            "{ \"id\"=\"${body}\", \"data\":\"some data\" }");
        weaveAddMockendpointAsLast("requestNumbersFromAPI", "result");
        weaveAddMockendpointAsLast("requestDataWithIdFromAPI", "splitResult");

        MockEndpoint mockResultEndpoint = getMockEndpoint("mock:result");
        mockResultEndpoint.expectedMessageCount(1);

        MockEndpoint mockSplitResultEndpoint = getMockEndpoint("mock:splitResult");
        mockSplitResultEndpoint.expectedMessageCount(5);

        startCamelContext();

        template.sendBodyAndHeader("direct:requestNumbersFromAPI", null, "jwt", "not-valid-jwt");

        mockResultEndpoint.assertIsSatisfied();
        mockSplitResultEndpoint.assertIsSatisfied();
    }

    @Override
    protected RoutesBuilder createRouteBuilder() throws Exception {
        
        return new RouteBuilder(){

            @Override
            public void configure() throws Exception {

               
                AggregationStrategy aggregationStrategy = AggregationStrategies
                    .flexible()
                    .accumulateInCollection(ArrayList.class);

                from("direct:requestNumbersFromAPI")
                    .routeId("requestNumbersFromAPI")
                    .setBody().constant(null)
                    .setHeader("Authorization")
                    .simple("Bearer "+"${header.jwt}")
                    .to("https://call/api/that/returns/numbers")
                    .unmarshal().json(JsonLibrary.Jackson, Integer[].class)
                    .split(body(), aggregationStrategy)
                        .to("direct:requestDataWithIdFromAPI")
                    .end()
                    //Logs resulting exchange body, headers and properties.
                    .to("log:loggerName?showAll=true")
                ;

                from("direct:requestDataWithIdFromAPI")
                    .routeId("requestDataWithIdFromAPI")
                    .setHeader("Authorization").simple("Bearer "+"${header.jwt}")
                    .log("Calling API with number: ${body}")                    
                    .toD("https://call/another/api/with/number/${body}")
                ;
            }
        };
    }

    @Override
    public boolean isUseAdviceWith() {
        return true;
    }

    private void replaceHttpEndpointWithSimpleResponse(String routeId, String simpleResponse) throws Exception {

        AdviceWith.adviceWith(context(), routeId, a -> {

            a.weaveByToUri("http*")
                .replace()
                .setHeader(Exchange.HTTP_RESPONSE_CODE).constant(200)
                .setBody().simple(simpleResponse);
        });
    }

    private void weaveAddMockendpointAsLast(String routeId, String mockName) throws Exception {

        AdviceWith.adviceWith(context(), routeId, a -> {

            a.weaveAddLast()
                .to("mock:" + mockName);
        });
    }
}