How to send a file attachment in the form-data parameter of the request to an API

I am trying to invoke an API which accepts request with form-data parameters, one of the parameter is a file , which can be of any type(.pdf/.jpg/.doc). When I try to pass the path of the file as value in parameters, I get an error from the API - the request was rejected because no multipart boundary was found.

When I try to send the file as an attachment , the file is not received in the expected format, instead it is received as application/octet-stream.

Request to please suggest options to send the file using the HTTP request acctivity.

Hello @Nagareetha_Baskaran!

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Hello Nagareetha,
In this video, you can see how I upload files to multiple systems (Maybe this will help you with your issue):
Uipath upload files in Jira (REST API) (HTTP REQUEST) | Jira REST API upload file - YouTube
ServiceNow Upload files without Administrator Rights with UiPath Robots | RPA files | REST API file - YouTube
Cristian Negulescu

Hello Nagareetha,
In this video, I use multipart/form-data:

0:20 cURL example
1:35 Send the command from POSTMAN
2:50 Implement the code in C#
4:20 Run the code
4:50 Visual Basic code VB.NET
6:20 New Process on UiPath Studio with Invoke Code
7:20 Imports Libraries in UiPath Studio
8:30 Run the Robot to Upload and Download the file

Dim client As HttpClient = New HttpClient()
client.BaseAddress = New Uri(“YOUR URL”)
client.DefaultRequestHeaders.Accept.Add(New MediaTypeWithQualityHeaderValue(“application/vnd.openxmlformats-officedocument.wordprocessingml.document”))
Dim byteArray As Byte() = Encoding.ASCII.GetBytes(“username:password”)
client.DefaultRequestHeaders.Authorization = New AuthenticationHeaderValue(“Basic”, Convert.ToBase64String(byteArray))Dim byteArray As Byte() = Encoding.ASCII.GetBytes(“username:password”)
// for OAUTH2
client.DefaultRequestHeaders.Add(“authorization”, “Bearer YOUR TOKEN”)
Dim request As MultipartFormDataContent = New MultipartFormDataContent()
request.Add(New StringContent(“tags”), “Bad”)
request.Add(New StringContent(“displayreferencetext”), “true”)
request.Add(New StringContent(“similaritythreshold”), “0.63”)
request.Add(New StreamContent(File.OpenRead(“C:\8A.docx”)), “file”, (New FileInfo(“C:\8A.docx”).Name))
Dim response As HttpResponseMessage = client.PostAsync(“”, request).Result
Dim strm As Stream = response.Content.ReadAsStreamAsync.Result
Dim doc As Byte()
Dim ms As MemoryStream = New MemoryStream()
doc = ms.ToArray()
File.WriteAllBytes(“C:\rpa\FORDOWNLOAD\rez.docx”, doc)

Cristian Negulescu

Hi @Cristian_Negulescu ,

This code didn’t work, few of them are not valid, also I have installed the package and also imported that namespace too.

Be sure you do all the steps from this timestamp of the movie:

Save and then restart the UiPath Studio.
As I Show in my movie the code was working for me.

I have restarted the studio and also the system as well… also I have one more query , I have to pass one more item in body and it’s data is like

[{“name”: “ABC Field”, “values”: [{“value”: “UiPath”}]}]

How should I pass this value?

This is JSON you need to build like:

Okay will try again thank you.

If you don’t mind can you have a look to this topic, I am struggling to get this completed.

I have checked and rectified the issue and fixed it, it was with the namespace, I was missing

But, on fixing it raise another concern I am keep getting 400 error whereas I had replicated the body inputs as I configured in Postman but over postman its working but in the UiPath I am keep getting the same 400 error, can you help? it’s a form-data POST method

Dim client As HttpClient = New HttpClient()
client.BaseAddress = New Uri("")

client.DefaultRequestHeaders.Add("authorization","Bearer XXX")
Dim request As MultipartFormDataContent = New MultipartFormDataContent()
request.Add(New StringContent("docId"),"CW1270984")
request.Add(New StreamContent(File.OpenRead(in_file)), "file", (New FileInfo(in_file).Name))

Dim response As HttpResponseMessage = client.PostAsync("", request).Result

Can you please help me rectify, why It giving this response?

This is the error I received as response

08/31/2022 18:15:48 => [Debug] StatusCode: 401, ReasonPhrase: ‘Unauthorized’, Version: 1.1, Content: System.Net.Http.StreamContent, Headers:
Connection: keep-alive
CF-Ray: 7435dd85aae80e98-BOM
Strict-Transport-Security: max-age=2592000; includeSubDomains; preload
Vary: Cookie
Vary: Origin
CF-Cache-Status: DYNAMIC
evisort-trace-id: b1283fc0-83bc-4679-82ef-69de5f4e029f
referrer-policy: no-referrer-when-downgrade
x-content-type-options: nosniff
x-frame-options: DENY
alt-svc: h3=“:443”; ma=86400, h3-29=“:443”; ma=86400
Cache-Control: no-cache
Date: Wed, 31 Aug 2022 12:45:48 GMT
Server: cloudflare
WWW-Authenticate: Bearer realm=“api”
Content-Length: 31
Allow: POST
Content-Type: application/json
Expires: Thu, 01 Jan 1970 00:00:01 GMT

I don’t know send Print Screen with Postman.