Postman - Loop same or different request with different query params in a collection

Question

I am trying to add some new requests to existing collection. The first request is getting the values, which gives me the result as an object array with ids. I want to use the ids from the object and perform an update with another request.

How can I iterate over the ids for the next request.

I tried using the pm.collectionVariables and assign the values and used setNectRequest in a for loop. It only executes once with the last id.

My GET request:

URL: {{api_url}}/resourcetypes

Tests:
let responseJson = pm.response.json();
let filteredResourceTypesIds = responseJson.values.map((type) => type.id)

pm.collectionVariables.set("filteredResourceTypesIds", filteredResourceTypesIds);

if (!filteredResourceTypesIds || filteredResourceTypesIds == null || filteredResourceTypesIds == undefined) {
    return;
}

for (i = 0; i <= filteredResourceTypesIds.length; i++) {
    console.log(i)
    pm.collectionVariables.set("resourceTypeId", filteredResourceTypesIds[i]);
    postman.setNextRequest("Add Property");
}

My Patch Request :

URL: {{api_url}}/resourcetypes/{{currentRsourceTypeId}}

Pre-script: let currentResourceTypeId = pm.collectionVariables.get("resourceTypeId");

Answer 1

In the Get Resource IDs API,setting array variable

In tests tab

let filteredResourceTypesIds = responseJson.typeIDs.map((type) => type.id)
pm.collectionVariables.set("filteredResourceTypesIds", JSON.stringify(filteredResourceTypesIds));

In the Patch Resource ID API, get array variable and shift

In Pre-request Script tab

let filteredResourceTypesIds = JSON.parse(pm.collectionVariables.get("filteredResourceTypesIds"));
pm.collectionVariables.set("currentRsourceTypeId", filteredResourceTypesIds.shift())
pm.collectionVariables.set("filteredResourceTypesIds", JSON.stringify(filteredResourceTypesIds));
if (filteredResourceTypesIds.length > 0){
    postman.setNextRequest("Update Resource"); // <- Patch Request Name
}

Mocking Server

It provides Two APIs

GET http://localhost:3000/api/resourcetypes

PATCH http://localhost:3000/api/resourcetypes/:id

mocking-server.js

const express = require('express');
const bodyParser = require('body-parser');

const app = express();
const port = 3000;

app.use(bodyParser.json());


// Mock data for demonstration purposes
const resourceTypes = [
    { id: 1, name: 'Type A' },
    { id: 2, name: 'Type B' },
    { id: 3, name: 'Type C' }
];

app.get('/api/resourcetypes', (req, res) => {
    res.json({ typeIDs: resourceTypes });
});

app.patch('/api/resourcetypes/:typeId', (req, res) => {
    const typeId = parseInt(req.params.typeId);
    const updateData = req.body;

    // Find and update the resource type
    const resourceType = resourceTypes.find(type => type.id === typeId);
    if (resourceType && updateData) {
        Object.assign(resourceType, updateData);
        res.json(resourceType);
    } else {
        res.status(404).json({ error: 'Resource Type not found' });
    }
});

app.listen(port, () => {
    console.log(`Server running on http://localhost:${port}`);
});

Install Dependencies

npm install express body-parser

Run Mocking Server

node mock-server.js

Postman Collection File

Import as 1-demo-postman-collection.json

{
    "info": {
        "_postman_id": "ef4bd661-b94e-4099-b512-a2268c5d5fc5",
        "name": "1-demo",
        "schema": "https://schema.getpostman.com/json/collection/v2.1.0/collection.json",
        "_exporter_id": "1826150"
    },
    "item": [
        {
            "name": "Get Resource Types",
            "event": [
                {
                    "listen": "test",
                    "script": {
                        "exec": [
                            "const responseJson = pm.response.json();",
                            "let filteredResourceTypesIds = responseJson.typeIDs.map((type) => type.id)",
                            "console.log(filteredResourceTypesIds);",
                            "pm.collectionVariables.set(\"filteredResourceTypesIds\", JSON.stringify(filteredResourceTypesIds));"
                        ],
                        "type": "text/javascript"
                    }
                }
            ],
            "request": {
                "method": "GET",
                "header": [],
                "url": {
                    "raw": "{{api_url}}/resourcetypes",
                    "host": [
                        "{{api_url}}"
                    ],
                    "path": [
                        "resourcetypes"
                    ]
                }
            },
            "response": []
        },
        {
            "name": "Update Resource",
            "event": [
                {
                    "listen": "prerequest",
                    "script": {
                        "exec": [
                            "let filteredResourceTypesIds = JSON.parse(pm.collectionVariables.get(\"filteredResourceTypesIds\"));",
                            "console.log(filteredResourceTypesIds);",
                            "pm.collectionVariables.set(\"currentRsourceTypeId\", filteredResourceTypesIds.shift())",
                            "pm.collectionVariables.set(\"filteredResourceTypesIds\", JSON.stringify(filteredResourceTypesIds));",
                            "if (filteredResourceTypesIds.length > 0){",
                            "    postman.setNextRequest(\"Update Resource\");",
                            "}"
                        ],
                        "type": "text/javascript"
                    }
                },
                {
                    "listen": "test",
                    "script": {
                        "exec": [
                            "const responseJson = JSON.parse(responseBody);",
                            "const currentRsourceTypeId = pm.collectionVariables.get(\"currentRsourceTypeId\")",
                            "pm.test('Current Resource Type should be response ID:  ' + responseJson.id, function () {",
                            "    pm.expect(responseJson.id).to.equal(currentRsourceTypeId);",
                            "});"
                        ],
                        "type": "text/javascript"
                    }
                }
            ],
            "request": {
                "method": "PATCH",
                "header": [],
                "body": {
                    "mode": "raw",
                    "raw": "{\n    \"name\": \"New Type name {{currentRsourceTypeId}}\"\n}",
                    "options": {
                        "raw": {
                            "language": "json"
                        }
                    }
                },
                "url": {
                    "raw": "{{api_url}}/resourcetypes/{{currentRsourceTypeId}}",
                    "host": [
                        "{{api_url}}"
                    ],
                    "path": [
                        "resourcetypes",
                        "{{currentRsourceTypeId}}"
                    ]
                }
            },
            "response": []
        }
    ],
    "event": [
        {
            "listen": "prerequest",
            "script": {
                "type": "text/javascript",
                "exec": [
                    ""
                ]
            }
        },
        {
            "listen": "test",
            "script": {
                "type": "text/javascript",
                "exec": [
                    ""
                ]
            }
        }
    ],
    "variable": [
        {
            "key": "filteredResourceTypesIds",
            "value": "[]",
            "type": "string"
        },
        {
            "key": "currentRsourceTypeId",
            "value": "1",
            "type": "string"
        },
        {
            "key": "api_url",
            "value": "http://localhost:3000/api",
            "type": "string"
        }
    ]
}

Postman Request

Get Resource Types

Update Resource

After Import that collection file, you can get the whole scrips

Collection Variables

Run looping - collection

Result

looped Patch request three times by resource IDs array.