Javascript 从graphql查询到json查询

有了这个GraphQL，我如何在Javascript中使用JSON执行类似的请求

使用GraphQL，示例中的查询为：

{
  trip(
    from: {place: "NSR:StopPlace:5533" },
    to: {place:"NSR:StopPlace:5532"}
  ) 
    {
    tripPatterns{duration}
  } 
}

根据文档，要查询的URL为

以下是我在Javascript中尝试的内容：

var url = "https://api.entur.io/journey-planner/v2/graphql";

var tripquery = 
{
    trip: 
    {
        __args: {
            from : {place :"NSR:StopPlace:5533" },
            to : {place :"NSR:StopPlace:5532" }                     
        },
        tripPatterns: {
            duration : true             
        }
    }
};

function jsonQuery(){

    var qry = JSON.stringify(tripquery);
    var url_qry = url + "?query=" + qry;

    var xhttp = new XMLHttpRequest();
    xhttp.open("POST", url_qry, true);
    xhttp.setRequestHeader("Content-Type", "application/json");

    xhttp.onreadystatechange = function(){
        console.log("onreadystatechange");
        if(xhttp.readyState === 4 && xhttp.status === 200){
            console.log("json-query-OK");
            console.log(xhttp.responseText);
        }
        else{
            console.log("xhttp.status      : " + xhttp.status);
            console.log("xhttp.statusText  : " + xhttp.statusText);
            console.log("xhttp.readyState  : " + xhttp.readyState);
            console.log("xhttp.responseType: " + xhttp.responseType);
            console.log("xhttp.responseText: " + xhttp.responseText);
            console.log("xhttp.responseURL : " + xhttp.responseURL);
            console.log("json-not-ok");
        }
    };



    xhttp.send();
    console.log("query sent");
}

上述代码将在控制台中产生此输出：

query sent
api.entur.io/journey-planner/v2/graphql?query={%22trip%22:{%22__args%22:{%22from%22:{%22place%22:%22NSR:StopPlace:5533%22},%22to%22:{%22place%22:%22NSR:StopPlace:5532%22}},%22tripPatterns%22:{%22duration%22:true}}}:1 POST https://api.entur.io/journey-planner/v2/graphql?query={%22trip%22:{%22__args%22:{%22from%22:{%22place%22:%22NSR:StopPlace:5533%22},%22to%22:{%22place%22:%22NSR:StopPlace:5532%22}},%22tripPatterns%22:{%22duration%22:true}}} 400 (Bad Request)
query.js:29 onreadystatechange
query.js:35 xhttp.status      : 400
query.js:36 xhttp.statusText  : Bad Request
query.js:37 xhttp.readyState  : 2
query.js:38 xhttp.responseType: 
query.js:39 xhttp.responseText: 
query.js:40 xhttp.responseURL : https://api.entur.io/journey-planner/v2/graphql?query={%22trip%22:{%22__args%22:{%22from%22:{%22place%22:%22NSR:StopPlace:5533%22},%22to%22:{%22place%22:%22NSR:StopPlace:5532%22}},%22tripPatterns%22:{%22duration%22:true}}}
query.js:41 json-not-ok
query.js:29 onreadystatechange
query.js:35 xhttp.status      : 400
query.js:36 xhttp.statusText  : Bad Request
query.js:37 xhttp.readyState  : 3
query.js:38 xhttp.responseType: 
query.js:39 xhttp.responseText: No query found in body
query.js:40 xhttp.responseURL : https://api.entur.io/journey-planner/v2/graphql?query={%22trip%22:{%22__args%22:{%22from%22:{%22place%22:%22NSR:StopPlace:5533%22},%22to%22:{%22place%22:%22NSR:StopPlace:5532%22}},%22tripPatterns%22:{%22duration%22:true}}}
query.js:41 json-not-ok
query.js:29 onreadystatechange
query.js:35 xhttp.status      : 400
query.js:36 xhttp.statusText  : Bad Request
query.js:37 xhttp.readyState  : 4
query.js:38 xhttp.responseType: 
query.js:39 xhttp.responseText: No query found in body
query.js:40 xhttp.responseURL : https://api.entur.io/journey-planner/v2/graphql?query={%22trip%22:{%22__args%22:{%22from%22:{%22place%22:%22NSR:StopPlace:5533%22},%22to%22:{%22place%22:%22NSR:StopPlace:5532%22}},%22tripPatterns%22:{%22duration%22:true}}}
query.js:41 json-not-ok

Json对象中的

\uu args

是我从一个在线示例中获得的，但我还没有真正理解它

---

也许我不确定到底要搜索什么，但我找不到关于如何将此GraphQL查询转换为JSON对象的好解释。

我遇到了同样的问题，我是这样做的：

{
  c_con_tic_PTF(dz: CR, docmanId: 123) {
    docmanId
    dz
    data
  }
}

我尝试在OS X中以curl命令的形式发送此请求：

我得到了我想要的回应

因此，您希望从graphQL查询中生成如下内容：

{ "query": "{  cz_atlascon_etic_PTF(docmanId: 123, dz: CR) { docmanId, dz, data }}" }

现在只需使用JS发送请求。 如果它对您有任何帮助，我的请求在Java中就是这样的：

HttpRequest mainRequest =
HttpRequest.newBuilder()
.uri(URI.create("my graphQL endpoint"))
.POST(HttpRequest.BodyPublishers.ofString("{ \"query\": \"{  c_con_tic_PTF(docmanId: 123, dz: CR) { docmanId, dz, data }}\" }"))
.build();

---

在Javascript中实现这一点的一种方法是使用FetchAPI。我过去就是这样做的。您可以通过复制下面的代码，然后将其粘贴到chromedev工具并运行来测试它

async function makeGraphQlQuery(urlToResource) {
    const queryObject = {
      query:
        '{ trip( from: {place: "NSR:StopPlace:5533" }, to: {place:"NSR:StopPlace:5532"}) {tripPatterns{duration}} }',
    };
    const response = await fetch(urlToResource, {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify(queryObject),
    });

    const json = response.json();

    return json;
}

async function sendAsync() { 
  const res = await makeGraphQlQuery('https://api.entur.io/journey-planner/v2/graphql');
  console.log(res); 
}
sendAsync().catch(err => console.log('Error in query', err));

---

我见过的有线协议最好的定义是。GraphQL查询语法没有标准的JSON转换；将查询字符串作为JSON字符串传递到一个小对象包装器中。

async function makeGraphQlQuery(urlToResource) {
    const queryObject = {
      query:
        '{ trip( from: {place: "NSR:StopPlace:5533" }, to: {place:"NSR:StopPlace:5532"}) {tripPatterns{duration}} }',
    };
    const response = await fetch(urlToResource, {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify(queryObject),
    });

    const json = response.json();

    return json;
}

async function sendAsync() { 
  const res = await makeGraphQlQuery('https://api.entur.io/journey-planner/v2/graphql');
  console.log(res); 
}
sendAsync().catch(err => console.log('Error in query', err));