How can I use Object (array of objects only) getting in response of API as input of another API who is expecting an array of Objects?

Question

I am calling one API "getProjectListForInstance" and getting result in response which is an array of objects. Like this :

[ { "_id": "uyuyiuyiuy", "project_name": "Project1", }, { "_id": "hjhjhjhjkh", "project_name": "Project2", } ]

   return new Promise((resolve, reject) => {
          RESTService.getProjectListForInstance(previousInstance)
          .then((result) => {
            this.copyProjectInfo(result);
          });
        });

Now using above result in below code.

  copyProjectInfo(projects) {
        console.log('copyProjectInfo');             
      
        return new Promise((resolve, reject) => {
            RESTService.createProjectInfoForNewInstance(projects)
            .then((result) => {
              console.log("Successfully done");
              console.log(result);
            }); 
        });
      },

The above code is not working. Getting 502 but when I am creating an array in code itself like below, then it is working fine.

copyProjectInfo(projects) {
      console.log('copyProjectInfo');             
      let details = 
        [
          {
           "_id": "uyuyiuyiuy",
           "project_name": "Project1",
           },
          {
           "_id": "hjhjhjhjkh",
           "project_name": "Project2",
         }
       ];
        return new Promise((resolve, reject) => {
            RESTService.createProjectInfoForNewInstance(details)
            .then((result) => {
              console.log("Successfully done");
              console.log(result);
            }); 
        });
      },

Do I need to cast the Object received from first API before using it as an input for second API? and How?

Thanks, Jyoti

You should remove those Promise constructors and return the Promise from the `RESTService` methods directly. This is known as a [Promise Constructor anti-pattern](https://stackoverflow.com/questions/23803743/3068190). Make sure to use [`catch()`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise/catch) to handle any errors too. — samthecodingman, Aug 05 '21 at 14:06

score 0 · Answer 1 · answered Aug 05 '21 at 13:13

I think you can try to use async/await syntax to do the jobs. I also remove all the unnecessary Promises wrapper.

example below:

(async function run() {
  try {
    const projects = await RESTService.getProjectListForInstance(
      previousInstance
    );

    const result = await RESTService.createProjectInfoForNewInstance(projects);

    console.log(result);
  } catch (err) {
    console.log(err);
  }
})();

How can I use Object (array of objects only) getting in response of API as input of another API who is expecting an array of Objects?

1 Answers1