How to pass a file to an API from Azure Logic App

Question

I have a simple Logic App. The trigger is on New file (ex: Dropbox, OneNote, etc.) I want to pass the filename and the fileContent to a API APP (web Api). But I got error, or worse the content is null once in the API!

The API is in C#.

How do you pass a file (ex: pdf, png) to and API from Logic App

UPDATE:

In Logic App here my action code:

"UploadNewFile": {
"inputs": {
    "method": "post",
    "queries": {
        "filedata": {
            "fileName":"@triggerOutputs()['headers']['x-ms-file-name']",
            "fileContent":"@base64(triggerBody())"
        }
    },
    "uri": "https://smartuseconnapiapp.azurewebsites.net/api/UploadNewFile"
},
"metadata": {
    "apiDefinitionUrl": "https://smartuseconnapiapp.azurewebsites.net/swagger/docs/v1",
    "swaggerSource": "website"
},
"runAfter": {},
"type": "Http"

}

In my API App, If the function is declared like this filedata is null

[Route("api/UploadNewFile")]
[HttpPost]
public HttpStatusCode UploadNewFile([FromBody] string filedata)

And if I don't add the [FromBody] like that I got an error.

[Route("api/UploadNewFile")]
[HttpPost]
public HttpStatusCode UploadNewFile(string filedata)

Answer 1

I found how to to it.

I needed to pass the filename in the querystring and the file in the body of the HTTP Request. Today, it's not possible to do it using the design view so you need to go in code view.

In the Logic App code

"queries": {
    "fileName": "@{triggerOutputs()['headers']['x-ms-file-name']}"
    },
"body": "@triggerBody()"

In the API App code

public HttpResponseMessage UploadNewFile([FromUri] string fileName)
{
   var filebytes = Request.Content.ReadAsByteArrayAsync();

   [...]
}

A more detailed explanation can be found in this blog post: http://www.frankysnotes.com/2017/03/passing-file-from-azure-logic-app-to.html