Chaining APIs, but running some of them in a loop

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1

I have 3 APIs.
API#1 - GET {{endPoint}}/event/{{customerId}}/orders
API#2 - POST {{endPoint}}/pullOrders/{{orderId}}/claims
API#3 - DELETE {{endPoint}}/pullOrders/{{orderId}}/events

Response of API#1 is a json with the orderIDs

    {
        "List": [
            {
            "OrderId": "c6882585",
            "Type": "pull"
        },
        {
            "OrderId": "a2f818e7",
            "Type": "pull"
        },
        {
            "OrderId": "1f45e306",
            "Type": "pull"
        }
    ]
}

The input to API#2 is the orderId from the response of API#1
The response of API#2 is a json with partNumber for a particular customerId. The response could be empty/null with varying number of partNumber with other customerId

[
    {
        "EventId": "46323beaf738",
        "PartNumber": "22b188f7",
    },
    {
        "EventId": "5024519db933",
        "PartNumber": "2c2d8757",
    }
]

These partNumber are input to API#3 in it’s body
Body of API#3

{
    "partNumberList": [22b188f7, 2c2d8757]
}

The goal is to delete all order history for a customer by chaining API#1, API#2 and API#3

In Tests of API#1 I get all the orderIds in test and save it in a variable

const responseJson = pm.response.json();
var orderIdList = responseJson.List;
var orderIds = [];
for(var index in orderIdList) {
    orderIds.push(orderIdList[index].OrderId);
}
pm.variables.set("orderIds", JSON.stringify(orderIds));
pm.variables.set("orderIdsIndex", 0);

In the Pre-request Script of API#2 I set the call to API#2 with the orderId from API#1

var orderIds = JSON.parse(pm.variables.get('orderIds'));
var index = parseInt(pm.variables.get('orderIdsIndex'));
pm.variables.set('orderId', orderIds[index]);
if (index + 1 < orderIds.length){
    pm.variables.set('orderIdsIndex', index + 1);
    postman.setNextRequest('API#2');
}else{
    postman.setNextRequest(null);
}

Till this point things work as expected, i.e. API#2 is called in a loop 3 times for 3 orderIds.
In Tests of API#2 I have tried the following. The run stops when partNumbers array below is non empty. It calls API#3 and stops. I want it to continue to the next iteration.

const responseJson = pm.response.json();
var partNumbers = [];
for (var key in responseJson){
    partNumbers.push(responseJson[key].PartNumber);
}
pm.variables.set('partNumbers', JSON.stringify(partNumbers));
if (receiptHandles.length != 0) {
    postman.setNextRequest('API#3');
}else{
    postman.setNextRequest('API#2');
}

And in body of API#3 I have

{
    "partNumberList": {{partNumbers}}
}
2

Hey @ontherocks :wave: Welcome to the Postman Community :tada:

Just trying to understand what you want to achieve here - when you say “next iteration”, should it go back to API#2 for the 2nd orderId?

I have an example of looping requests in the following public workspace where an array gets updated with each iteration using shift().
https://www.postman.com/speeding-resonance-133102/workspace/how-to-s-workspace/collection/12689164-25ccdc45-b1b4-483a-85d9-8b7cf9f69799

Hope this helps, but let me know if you have further questions :wink:

3

Yes, I am expecting it to go back to API#2 for the 2nd orderId.

4

Hey @ontherocks :wave:
Thanks for clarifying! I have updated my collection to simulate your case more closely :wink:

I hope this is helpful!

5

why can’t you store everything before hand ?

in API 1 test use:

//storing all orderids to a list 
pm.variable.set("orderIDList",pm.response.json().List.map(elem=>elem.OrderId))

in pre-request of API2

//Getting orderID from the list in the left to right order
let orderIDList = pm.variable.get("orderIDList")
pm.variables.set("orderId", orderIDList.shift())
pm.variables.set("orderIDList", orderIDList)
// Doing sendRequest till all orderIDs are executed
orderIDList.length ? postman.setNextRequest(pm.info.requestName):null

In test script of API2

//storing PartNumber for each orderID as a List of object coontaining 
//orderID:[partnumber1,partnumber2]
let obj = {}
obj[pm.variables.get("orderId")] =  pm.response.json().map(elem=>elem.PartNumber)
let partNumberList = pm.variables.get("partNumberList") 
partNumberList ? partNumberList.push(obj) : partNumberList=[obj]
pm.variables.set("partNumberList",partNumberList)

and in Pre request of API3

//sending each orderid with the full PartNumberList
let partNumberList = pm.variable.get("partNumberList")
let partNumberMap = partNumberList.shift()
pm.variables.set("orderId", Object.keys(partNumberMap).shift())
pm.variables.set("partNumbers", partNumberMap[orderId])
pm.variables.set("partNumberList", partNumberList)  

partNumberList.length ? postman.setNextRequest(pm.info.requestName):null
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