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Upload 1gb file via API call (no flow) using UPLOAD SESSION + CHUNK

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Posted on by CU26080721-1

Hi. I am building an app canvas in power apps. In this app there are the default Sharepoint FileAttachmentControl and a Button.
I am looking for something like this tutorial: Upload Large Files.
In the OnSelect property of the Button component, I structured my code into two parts.
- In the first part: I create the Upload Session.
- In the second part: I split my file into chunks and upload those chunks to the URL generated in the first part.

//OnSelect: 1st STEP
Set(
uploadSessionResult;
'HTTPwithMicrosoftEntraID(preautorizzato)'.InvokeHttp(
"POST";
"https://graph.microsoft.com/v1.0/sites/" & siteId & "/drives/" & driveId & "/root:/" & folderName & "/" & fileName & ":/createUploadSession";
{
ContentType: "application/json"
;
body: "{""item"": {""@microsoft.graph.conflictBehavior"": ""replace"", ""name"": ""m24_l1.pdf""}}"
}
)

)
Set( uploadUrl; Text(uploadSessionResult.uploadUrl) );;

This 1st part works fine.

Then I have to :
1) read the attachment size
This tutorial worked fine for me. I only changed the SizeLabel property cause I don't need to work with "MB" but "bytes"
(cause the Chunk Maximum Size is 327680 bytes)

Label: ((Len(varJSON) - 814) / 1370000  )*1024*1024
2) extract the attachment binary data 
1.Upload

 
//OnSelect: 2nd STEP
Set(
    BinaryData;
    JSON(ImgFile.Image; JSONFormat.IncludeBinaryData)
);;
 
Set(
    varBase64Only;
    Left(
        Index(
            Split(BinaryData; "base64,");
            2
        ).Value;
        Len(
            Index(
                Split(BinaryData; "base64,");
                2
            ).Value
        ) - 1
    )
);;
3) Calculate the number of Chunks for the current Attachment
//OnSelect: 3rd STEP
Set( varFileSize; Value(SizeLabel.Text));;
Set( ChunkSize; 327680);; 
Set(totalChunks; RoundUp(varFileSize / ChunkSize; 0));;
4) Divide the file into chunks and upload every single chunk
 
          //OnSelect: Last STEP
ClearCollect(ChunkTable;                     
    ForAll(
        Sequence(totalChunks);
        {
            startByte: (Value - 1) * ChunkSize;
            endByte: Min(Value * ChunkSize - 1; varFileSize - 1)
        }
    )
);;
 
ForAll(
    ChunkTable;
    With( 
         {
            chunkData: Mid(varBase64Only; ThisRecord.startByte + 1; ThisRecord.endByte - ThisRecord.startByte + 1);
            requestHeaders: Table(
    {key: "Content-Length"; value: Text(ThisRecord.endByte - ThisRecord.startByte + 1) };
    {key: "Content-Range"; value: "bytes " & ThisRecord.startByte & "-" & ThisRecord.endByte & "/" & varFileSize}
                       
         };
     'HTTPwithMicrosoftEntraID(preautorizzato)'.InvokeHttp("PUT"; uploadUrl;
           {headers: requestHeaders; body: chunkData}
       )    
     )
    );;


Result: PUTrequest ends with  ONE OR MORE ERRORS OCCURRED





Debug:  I noticed a strange behaviour and I think is the PUTrequest's failing reason.

ChunkTable is ok, but when I try to print Content-range  in that ForAll iteration , It occurs that:

varFileSize has the default value (something like -630) .

This happens during the 1st and the 2nd iteration of that ForAll ; after that, varFileSize has the right value.



PS: I am using the european settings , so  "comma" is replaced by ";"  and "every code line is closed by  ;; " 





 

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Building Power Apps

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ApiTrader 174 on at

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I struggle also with this endpoint, did you solve your problem? My error recomment to check my internet connection.

'HTTPwithMicrosoftEntraID(preauthorized)'.InvokeHttp(

"PUT",

'HTTPwithMicrosoftEntraID(preauthorized)'.InvokeHttp(

"POST",

"https://graph.microsoft.com/v1.0/me/drive/items/root:/Folder/AppCache/BillingTemplate.docx:/createUploadSession",

{

headers: Table(

{

key: "Content-Type",

value: "application/json"

}

),

body: JSON(

{

item: {

'@microsoft.graph.conflictBehavior': "rename",

description: "description",

driveItemSource: {'@odata.type': "microsoft.graph.driveItemSource"},

name: "BillingTemplate.docx"

},

deferCommit: true

},

JSONFormat.IncludeBinaryData

)

}

).uploadUrl,

{body: varBase64Only}

)

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D1d1 4 on at

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Hello,

I wanted to ask if you have found a solution to your problem. I am also looking to realize a chunked upload from PowerApps.

Thanks

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AZ-10040037-0 4 on at

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For people who have been struggling in uploading large size files on Power Apps (canvas apps).

Firstly Power Apps and Power Automate alone or together can be used to upload files to a data source like SharePoint document library. However there is a file size limitation on how many bytes can be transferred using Power Apps or Power Automate.

There are two ways to upload files to a data source like SharePoint document library.

Using the HttpRequest method of Office365Groups connector.

Using the InvokeHttp method of HTTPwithMicrosoftEntraID(preauthorized) connector

We have observed files up to 200Mb got uploaded to SharePoint document library via graph api using HttpRequest method of Office365Groups connector. However it does not work for large size files (>200Mb) due to timeout error. It also depends on the internet connection speed.

For InvokeHttp method of HTTPwithMicrosoftEntraID(preauthorized) connector, there are some known issues and limitations on using it.

Ref: https://learn.microsoft.com/en-us/connectors/webcontents/#known-issues-and-limitations

This simply means sending the base64 chunks is not possible as this method would convert the chunks again into base64 which would result in file corruption.

There is a well known technique to get base64 string of a file by using the image control and set it to the value of the attachment control. The problem here is that when we upload a file greater than 500Mb, the whole application just crash with out of memory error. This is due to the JSON function JSON(ImgFile.Image; JSONFormat.IncludeBinaryData) that cannot handle that large amount of binary data.

In a nutshell, Power Apps is a light weight Rapid Application Development platform to develop the apps with low code. It is not designed to do heavy lifting.

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