Power Platform Community Forum Thread Details

I created a Microsoft Power App to upload documents to Azure File (not blob). I use attachment control to collect the file, and then Power Automate flow to upload to Azure File.

Here is the Power Automate flow:

1) Power Apps (V2)

Text type input named "FileName"

File type input named "FileContent"

2) Create File (Azure File Storage)

Folder path established

File name: FileName

File content: FileContent

I added an Upload button with below code:

SaveFileToAzureFile.Run("Test",First(Attachment.Attachments))

Clicking the Upload button does successfully add the file with proper name to Azure File with the name "Test".

Here's the problem: The file gets to Azure File, but content is not openable. The files are only 1kb and open null. So it seems the File Content is not making its way. I'm assuming this is an intricacy with binary vs bas64.

I have tried JSON conversions:

ForAll(

Attachment.Attachments,

SaveFileToAzureFile.Run(

ThisRecord.Name,

{

Name: ThisRecord.Name,

ContentBytes: JSON(ThisRecord.Value, JSONFormat.IncludeBinaryData)

}))

I have tried sending .Value:

ForAll(

Attachment.Attachments,

SaveFileToAzureFile.Run(

ThisRecord.Name,

ThisRecord.Value

))

I have tried passing as a record:

ForAll(

Attachment.Attachments,

SaveFileToAzureFile.Run(

ThisRecord.Name,

{

name: ThisRecord.Name,

contentBytes: ThisRecord.Value

}))

And I have also tried base64 conversions in the flow:
base64ToBinary(triggerBody()?['FileContent']?['contentBytes'])

I have exhausted the help of AI and am now looking to real humans for the answer!

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Categories:

Connector development

Building Power Apps

Hello,

I have dealt with a similar scenario and got this to work with a component that I created to convert any files to Base64 by manipulating an Image control inside of it, here is the YAML code:

ComponentDefinitions:
  ConvertToBase64:
    DefinitionType: CanvasComponent
    CustomProperties:
      ToBase64:
        PropertyKind: Action
        DisplayName: ToBase64
        Description: A custom property
        ReturnType: Text
        Parameters:
          - FileData:
              Description: FileData
              DataType: Text
              Default: ="Text"
    Properties:
      Height: =1
      ToBase64: |-
        =Set(varImageValue,FileData);
        Mid(
            JSON(Image2.Image, JSONFormat.IncludeBinaryData),
            Find(",", JSON(Image2.Image, JSONFormat.IncludeBinaryData)) + 1,
            Len(JSON(Image2.Image, JSONFormat.IncludeBinaryData)) - Find(",", JSON(Image2.Image, JSONFormat.IncludeBinaryData)) - 1
        )
      Width: =1
    Children:
      - Image2:
          Control: Image@2.2.3
          Properties:
            BorderColor: =RGBA(0, 18, 107, 1)
            Image: =varImageValue
            X: =40
            Y: =40

I also created a component that uses the attachment control outside of a form control:

ComponentDefinitions:
  FileAttachment_2:
    DefinitionType: CanvasComponent
    CustomProperties:
      Attachments:
        PropertyKind: Output
        DisplayName: Attachments
        Description: A custom property
        DataType: Record
      Border:
        PropertyKind: Input
        DisplayName: Border
        Description: A custom property
        DataType: Color
        Default: =Color.Transparent
      Items:
        PropertyKind: Input
        DisplayName: Items
        Description: A custom property
        DataType: Table
        Default: =
      MaxAttachmentSize:
        PropertyKind: Input
        DisplayName: Max Attachment Size
        Description: A custom property
        DataType: Number
        Default: =100
      MaximumAttachments:
        PropertyKind: Input
        DisplayName: Maximum Attachments
        Description: A custom property
        DataType: Number
        Default: =5
      NoAttachmentText:
        PropertyKind: Input
        DisplayName: No Attachment Text
        Description: A custom property
        DataType: Text
        Default: ="There is nothing attached."
      OnAddFile:
        PropertyKind: Input
        DisplayName: OnAddFile
        Description: A custom property
        DataType: Record
        Default: =
      Reset:
        PropertyKind: Input
        DisplayName: Reset
        Description: A custom property
        DataType: Boolean
        Default: =true
    Properties:
      Attachments: |-
        ={FileAttachment: FileAttachmentControl_1.Attachments}
      Height: =80
      OnReset: =Reset(FileAttachmentControl_1)
      Width: =200
    Children:
      - FileAttachmentControl_1:
          Control: Attachments@2.3.0
          Properties:
            BorderColor: =FileAttachment_2.Border
            Color: =RGBA(255, 255, 255, 1)
            DropTargetBackgroundColor: =RGBA(0, 0, 0, 0)
            DropTargetBorderStyle: =BorderStyle.None
            Fill: =RGBA(0, 0, 0, 0)
            Font: =Font.'Open Sans'
            Height: =80
            HoverFill: =RGBA(186, 202, 226, 1)
            ItemColor: =RGBA(255, 255, 255, 1)
            ItemFill: =RGBA(56, 96, 178, 1)
            ItemHoverFill: =RGBA(186, 202, 226, 1)
            Items: =FileAttachment_2.Items
            Items.Name: =SampleStringField
            Items.Value: =SampleStringField
            MaxAttachmentSize: =FileAttachment_2.MaxAttachmentSize
            MaxAttachments: =FileAttachment_2.MaximumAttachments
            NoAttachmentsText: =FileAttachment_2.NoAttachmentText
            OnAddFile: =FileAttachment_2.OnAddFile
            PaddingTop: =10
            PressedColor: =RGBA(255, 255, 255, 1)
            PressedFill: =RGBA(0, 18, 107, 1)
            Reset: =FileAttachment_2.Reset
            Size: =8
            TabIndex: =1
            Tooltip: =
            Width: =200

Using these two components, I am then able to convert each attachment in the Attachment component with the ConvertToBase64 component within the button's OnSelect property and run the flow as such:

//For each attachment, convert to base64 and store in a collection
ForAll(
    AttachmentComponent.Attachments.FileAttachment As doc,
    Collect(
        colFilesToUpload,
        {
            FileName: doc.Name,
            FileContent:  ConvertToBase64.ToBase64(doc.Value),
            FolderPath: ""
        }
    )
);

//Send all attachments to flow
Set(varUploadFile, 'CreateFile'.Run(JSON(colFilesToUpload, JSONFormat.IncludeBinaryData));

Now in the Power Automate flow, the JSON output is received as text:

Parse the JSON:

Then, run an Apply to Each action for the Parse JSON Body:

Add a Create File action in the Apply to Each and iterate through the following items from the Parse JSON Body:

Here is the function for the File Content:

base64ToBinary(items('Apply_to_each')?['FileContent'])

Don't forget to let the users know that the upload was successful by returning a response from your flow:

//Notify if upload was successful
If( 
    !IsBlank(varUploadFile),
    Notify("Files uploaded successfully!", NotificationType.Success),
    Notify("Upload failed. Please try again.", NotificationType.Error)
);

If this response was helpful to you, please mark your post as resolved so that others may reference to it.