I recently added the BizTalk Transform Service Connector to a Logic App

When clicking on properties,  I discovered that I could access the API Definition as shown in the following figure

add

 

I found that I was able to download the  Swagger, TransformService.json, by clicking on  Download Swagger

swagger

The contents of the Swagger are shown below.

{
  "swagger": "2.0",
  "info": {
    "version": "1.0",
    "title": "BizTalk Transform Service"
  },
  "host": "transformservice5c0f3e70d14e444abd3b23a237533c15.azurewebsites.net",
  "schemes": [
    "http"
  ],
  "paths": {
    "/api/Transform": {
      "post": {
        "tags": [
          "Transform"
        ],
        "summary": "Transform",
        "description": "Transform action converts XML message from one format to another using the specified map that was already uploaded to Transform API App. If no map is specified, the map is automatically picked based on the source schema to which input XML conforms to.",
        "operationId": "Transform",
        "consumes": [
          "application/json",
          "text/json"
        ],
        "produces": [
          "application/json",
          "text/json"
        ],
        "parameters": [
          {
            "name": "inputXml",
            "in": "body",
            "description": "Specify the valid XML content that will conform to the source schema of a map in Transform API App. This can be an output from previous action in Flow App such as �Call RFC � SAP� or �Insert Into Table � SQL�.",
            "required": true,
            "schema": {
              "$ref": "#/definitions/TransformInput"
            },
            "x-ms-summary": "Input XML"
          },
          {
            "name": "mapName",
            "in": "query",
            "description": "Optional. Specify a valid map name that was already uploaded in Transform API App. If no map is specified, the map is automatically picked based on the source schema to which input XML conforms to.",
            "required": false,
            "x-ms-summary": "Map Name",
            "x-ms-visibility": "advanced",
            "type": "string",
            "default": ""
          }
        ],
        "responses": {
          "200": {
            "description": "Transform action executed successfully.",
            "schema": {
              "$ref": "#/definitions/TransformOutput"
            }
          },
          "400": {
            "description": "Bad Request. Input XML is empty/ Transform map is invalid / Input XML does not conform to the source schema of the map."
          },
          "404": {
            "description": "The specified map does not exist / There is no map configured in Transform API App that accepts the specifed input XML content"
          },
          "500": {
            "description": "Internal server error. A runtime error occured while executing the map. Check the input XML and the map."
          },
          "default": {
            "description": "Operation Failed."
          }
        },
        "deprecated": false
      }
    }
  },
  "definitions": {
    "TransformInput": {
      "description": "Transform Input Model Class",
      "required": [
        "InputXml"
      ],
      "type": "object",
      "properties": {
        "InputXml": {
          "description": "Specify the valid XML content that will conform to the source schema of a map in Transform API App. This can be an output from previous action in Flow App such as �Call RFC � SAP� or �Insert Into Table � SQL�.",
          "type": "string",
          "x-ms-summary": "Input XML"
        }
      }
    },
    "TransformOutput": {
      "description": "Transform Output Model Class",
      "required": [
        "OutputXml"
      ],
      "type": "object",
      "properties": {
        "OutputXml": {
          "description": "XML content that is created based on the input XML content using the specified map",
          "type": "string",
          "x-ms-summary": "Output XML"
        }
      }
    }
  }
}

I can use the “Add Rest Client” in Visual Studio to add the TransformService  API Service to my custom API or Web Application.

The key advantage of doing this is that i am able to call the TransformService outside a workflow.  I can do my mapping before the first step in as Logic App.