node-red-contrib-field-mapper 1.0.23

Input and output data mapper

npm install node-red-contrib-field-mapper


This module provides a “mapper” node in Node-RED for mapping JSON data from one format (i.e. input) to another (i.e. output).

This node can be helpful in scenarios where JSON data transformation is required or while integrating two different third-party APIs.

Mapper uses JSON specification file to assign values of input fields to output fields. Input JSON field can be a simple field or an object. Input fields/objects can be mapped to expected output fields/objects.

During runtime the “mapper” node will assign input fields/objects values to corresponding output fields/objects. Transformed JSON document will contain both input and output fields/objects. Mapper node will NOT delete any fields after transforming input JSON into desired output JSON document. “Change” node may be used to delete obsolete fields after transformation, if needed.

To make it easier for a standard third party integration, a public mapper definition repository is available which allows developers to select the required mapping for a JSON transformation.

Mapper definitions can be managed both publicly and privately.

Public Mapper Definition

Public mapper definitions are standard peer-reviewed repository for community sharing and usage to help keep definitions up-to-date. Intended to be used and maintained by community.

Contributions are welcome! See the contribution guidelines.

link: Public mapper definition repository

Private Mapper Definition

If your enterprise has a specific object model that will be used in integrations and you would like to keep those definitions private then you can point to a JSON file hosted on your own web servers.

Pre-requisites


The Node-RED Mapper requires Node-RED to be installed.

Install


To install the stable version use the Menu - Manage palette option and search for node-red-contrib-field-mapper, or run the following command in your Node-RED user directory - typically ~/.node-red:

npm install node-red-contrib-field-mapper

Or else install the package directly from Manage Palette

manage palette

Restart your Node-RED instance and you should have a “mapper” node available in the palette.

Get Started


After installing the mapper node, follow the below steps:

1. Drag the “mapper” node from the palette to the workspace.

2. Double click to open the Config node.

3. Click on the edit icon to Add new mapping in the mapping field.

4. Enter the URL for JSON consisting of input and output formats (See example below) and Click Add.

Usage


The mapper node can be utilized in any flow with input and output JSON data. Below is an example usage with an simple JSON inject node.

Example


  1. Add an Inject node with below sample JSON, You can add below data in Inject node properties by double clicking the inject node and changing the msg.payload type to JSON
  2. {
      "name": "eugene",
      "age": 26,
      "info": {
        "street": "home-street"
      },
      "test": "mapper"
    }
    
  3. Add Mapper node to the flow and edit the properties of mapper node by double clicking the mapper node
  4. You can create a new mapping by clicking on edit button on Mapper properties panel and having Add new Mappings... selected. add mapper
    • Select Mapping dropdown to view saved custom mappers

    • By default public sample.json file will be selected with sample mapper JSON object.

    • You can click on Load button to load JSON to schema field and edit if required.

    • Additionally you can also use private mapper definition by selecting private in dropdown and pasting the link of public S3 bucket/json file or available valid json definition.

    custom mapper

    Below is an example mapper JSON which takes sample user details as JSON input and converts it to new payload/data. We can also add new key-value pair which may or may not be present in input JSON.

  5. {
      "input": {
        "userId": "1",
        "name": "",
        "age": "",
        "info": {
          "street": ""
        },
        "test": ""
      },
      "output": {
        "dynamic-value": "mapper-data",
        "userId": "",
        "name": "",
        "age": "",
        "address": {
          "street": ""
        }
      }
    }
    

    Once schema is set you can click on Add button available on top right side of the mapper properties panel to save custom mapper.

  6. (Optional) You can select Clean up checkbox to remove un-mapped fields.
  7. Example:

    With Clean-Up:

    {
      "address": {
        "street": "home-street"
      },
      "name": "eugene",
      "dynamic-value": {
        "street": "home-street"
      },
      "age": 26
    }
    

    Without Clean-Up

    {
      "name": "eugene",
      "age": 26,
      "info": {
        "street": "home-street"
      },
      "test": "mapper",
      "address": {
        "street": "home-street"
      }
    }
    
  8. Set Field Values
    Click on the + add button at the bottom of mapper properties panel to add key mapping to output JSON.

    Example: Select info.street to address.street to add mapping

    Doing this will create a new property address into the incoming object or input JSON object, Existing key-value pairs will not be removed unless Clean up is checked.

  9. Attach the mapper node to the inject node.
  10. Attach debug node to mapper node
  11. On executing this flow, the expected output will be as follows,
  12. {
      "name": "eugene",
      "age": 26,
      "info": {
        "street": "home-street"
      },
      "test": "mapper",
      "address": {
        "street": "home-street"
      }
    }
    

    Example flow

    [
      {
        "id": "7f1163f7515c5d6f",
        "type": "tab",
        "label": "Mapper Node",
        "disabled": false,
        "info": "This module provides a “mapper” node in Node-RED for mapping JSON data from one format (i.e. input) to another (i.e. output).\n\nThis node can be helpful in scenarios where JSON data transformation is required or while integrating two different third-party APIs.",
        "env": []
      },
      {
        "id": "e9e8f7b9511cdde5",
        "type": "inject",
        "z": "7f1163f7515c5d6f",
        "name": "Sample JSON",
        "props": [
          {
            "p": "payload"
          }
        ],
        "repeat": "",
        "crontab": "",
        "once": false,
        "onceDelay": 0.1,
        "topic": "",
        "payload": "{\"name\":\"eugene\",\"age\":26,\"info\":{\"street\":\"home-street\"},\"test\":\"mapper\"}",
        "payloadType": "json",
        "x": 300,
        "y": 180,
        "wires": [["68f1d823be6dcbe3", "1c5f199f9f0a6f88"]]
      },
      {
        "id": "68f1d823be6dcbe3",
        "type": "Mapper",
        "z": "7f1163f7515c5d6f",
        "name": "Mapper v1.0.23",
        "rules": [
          {
            "pi": "userId",
            "po": "dynamic-value"
          },
          {
            "pi": "userId",
            "po": "dynamic-value"
          }
        ],
        "cleanup": false,
        "mapping": "18aada988a899f9e",
        "x": 590,
        "y": 180,
        "wires": [["876649f1c4f4e161"]]
      },
      {
        "id": "876649f1c4f4e161",
        "type": "debug",
        "z": "7f1163f7515c5d6f",
        "name": "",
        "active": true,
        "tosidebar": true,
        "console": false,
        "tostatus": false,
        "complete": "false",
        "statusVal": "",
        "statusType": "auto",
        "x": 940,
        "y": 180,
        "wires": []
      },
      {
        "id": "1c5f199f9f0a6f88",
        "type": "Mapper",
        "z": "7f1163f7515c5d6f",
        "name": "Mapper with clean-up",
        "rules": [
          {
            "pi": "info.street",
            "po": "address.street"
          },
          {
            "pi": "name",
            "po": "name"
          },
          {
            "pi": "info",
            "po": "dynamic-value"
          },
          {
            "pi": "age",
            "po": "age"
          }
        ],
        "cleanup": true,
        "mapping": "18aada988a899f9e",
        "x": 600,
        "y": 260,
        "wires": [["0e32244a81ebb7ba"]]
      },
      {
        "id": "0e32244a81ebb7ba",
        "type": "debug",
        "z": "7f1163f7515c5d6f",
        "name": "",
        "active": true,
        "tosidebar": true,
        "console": false,
        "tostatus": false,
        "complete": "false",
        "statusVal": "",
        "statusType": "auto",
        "x": 950,
        "y": 260,
        "wires": []
      },
      {
        "id": "18aada988a899f9e",
        "type": "Mapping",
        "name": "User Address",
        "url-type": "public",
        "url-public": "mappings/sample.json",
        "url-private": "",
        "schema": "{\"input\":{\"userId\":\"1\",\"name\":\"\",\"age\":\"\",\"info\":{\"street\":\"\"},\"test\":\"\"},\"output\":{\"dynamic-value\":\"mapper-data\",\"userId\":\"\",\"name\":\"\",\"age\":\"\",\"address\":{\"street\":\"\"}}}"
      }
    ]
    

    Demo


    https://www.youtube.com/watch?v=U3YuTAf7YG4

    Krysp Platform Features

    Flow execution metrics

    Multi-user capabilities

    Enhanced log viewer that shows application and system logs

    Contributions


    Development of Mapper Node happens in the open on GitHub, and we are grateful to the community for contributing bugfixes and improvements. Read below to learn how you can take part in improving mapper node.

    Contributing Guide

    Read our contributing guide to learn about our development process, how to propose bugfixes and improvements.

    Discussions and suggestions


    Use the Krysp Forum: https://www.krysp.io/forum to ask questions or to discuss new features.

Node Info

Version: 1.0.23
Updated 1 year, 1 month ago
License: ISC
Rating: not yet rated

Actions

Rate:

Downloads

5 in the last week

Nodes

  • Mapper

Keywords

  • node-red
  • mapper
  • formatter

Maintainers