How to include a file/file-contents in a Web Service call from NWC

I have the exact same question. Did you find a solution?

Hi All,

even this is an old one and archived, this was the only one I found regarding the topic: “How to send a file to a Web Service”.

I have created a Xtension in our  Nintex Cloud Tenant at <ourTenant>.workflowcloud.com/dashboard/xtensions and used a swagger-json like this:

{
  "swagger": "2.0",
  "info": {
    "title": "Watermark Service",
    "version": "1.0.0"
  },
  "host": "abcwebapp-h5dgdrfshyebdyad.germanywestcentral-01.azurewebsites.net",
  "basePath": "/api",
  "schemes": ["https"],
  "paths": {
    "/globalWatermark": {
      "post": {
        "operationId": "globalWatermark",
        "summary": "Upload a PDF file for global watermarking",
        "consumes": ["multipart/form-data"],
        "produces": ["application/pdf"],
        "parameters": [
          {
            "name": "X-Bearer-Token",
            "in": "header",
            "description": "AAD access token for this app registration (raw token, no 'Bearer ' prefix needed - the service adds it). Not named 'Authorization' because the Xtension relay collides with that reserved header name.",
            "required": true,
            "type": "string"
          },
          {
            "name": "file",
            "in": "formData",
            "description": "PDF file to watermark",
            "required": true,
            "type": "file"
          },
          {
            "name": "text",
            "in": "formData",
            "description": "Watermark text to stamp on the PDF. Defaults to 'Confidential' if omitted.",
            "required": false,
            "type": "string"
          },
          {
            "name": "fileName",
            "in": "formData",
            "description": "Name for the returned PDF file (used in the Content-Disposition header). Defaults to 'watermarked.pdf' if omitted; a '.pdf' extension is appended automatically if missing.",
            "required": false,
            "type": "string"
          }
        ],
        "responses": {
          "200": {
            "description": "Watermarking successful",
            "schema": {
              "type": "file"
            }
          },
          "400": {
            "description": "Bad request (no file uploaded, or not a PDF)"
          },
          "401": {
            "description": "Missing or invalid bearer token"
          },
          "413": {
            "description": "File exceeds the 15MB upload limit"
          },
          "429": {
            "description": "Too many requests - rate limited"
          },
          "500": {
            "description": "Server error"
          }
        }
      }
    }
  }
}

Please note that I am using an Azure App-Registration with a client secret to call my Azure-Web-App. Adjust the value for “host” to your Web-App default domain. This Web App must contain your service which will take the file.
If you upload the json to the Nintex-Xtensions, use ‘None’ as the Auth-Method. Create a nice icon and attach it during the configuration of the Xtension. This icon will then later be shown on the Workflow-Action if you drag it to the Designer. (I used 96*96 pixel).

Then in a Workflow obtain a token.

Use your tenant-id in URL.

Use the client_id of your App-Registration.
Use the client_secret of your App-Registration.

Use the Application-ID-URI of you App-Reg, starting with api://

Then use a Query JSON Action to get the Token from the sResContent variable and use this JSONPath expression: $.access_token (Store first result in: sToken)

Then configure your new Xtension:
Where spFile is a file object which I got from a “Get a file”-action
 

Hope that helps others.
Good luck