Delete Folder Using PowerShell

Using the /2/files/delete_v2 endpoint is the right way to delete a folder. Calling it will be similar to /2/files/upload, but with some important differences. 

The /2/files/upload endpoint is a "content-upload" endpoint, so it takes the parameters as JSON in the "Dropbox-API-Arg" header.

The /2/files/delete_v2 endpoint is an "RPC" endpoint though, so it takes the parameters as JSON in the request body.

If you have code for /2/files/delete_v2 that doesn't seem to be working, print out the response body you get when you call it. If the call isn't working, there should be an error message in the response body. (You may need to add some extra code to print that out, e.g., as shown in this post.)

Thank you for your reply, sorry that I don't understand everything you have explained here, this is the first time I've attempted anything like this.

The best I could do is to take the working upload code and change it to the below which isn't correct but the closest I could get to what I thought it should be. It seems that my Invoke-RestMethod command parameters are wrong and probably the headers too.

$TargetFilePath = "/20181008"
$DropBoxAccessToken = "<access-token>"

$arg = '{ "path": "' + $TargetFilePath + '" }'
$authorization = "Bearer " + $DropBoxAccessToken
 
$headers = New-Object "System.Collections.Generic.Dictionary[[String],[String]]"
$headers.Add("Authorization", $authorization)
$headers.Add("Dropbox-API-Arg", $arg)
$headers.Add("Content-Type", 'application/json')
 
Invoke-RestMethod -Method Delete -Uri https://api.dropboxapi.com/2/files/delete_v2 -Headers $headers

Here is the output after the PowerShell script fails:

Invoke-RestMethod : The remote server returned an error: (400) Bad Request.
At (SCRIPT LOCATION)\Dropbox-Delete.ps1:12 char:1
+ Invoke-RestMethod -Method Delete -Uri https://api.dropboxapi.com/2/fi ...
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : InvalidOperation: (System.Net.HttpWebRequest:HttpWebRequest) [Invoke-RestMethod], WebExc
   eption
    + FullyQualifiedErrorId : WebCmdletWebResponseException,Microsoft.PowerShell.Commands.InvokeRestMethodCommand

Can you print the response body as mentioned/linked in my last post? You'll want to retrieve the error message from it to debug things like this.

I just tried adding the code from each answer in that post but I get no output from PowerShell at all.

First one I tried:

$TargetFilePath = "/20181008"
$DropBoxAccessToken = "<access-token>"

$arg = '{ "path": "' + $TargetFilePath + '" }'
$authorization = "Bearer " + $DropBoxAccessToken
 
$headers = New-Object "System.Collections.Generic.Dictionary[[String],[String]]"
$headers.Add("Authorization", $authorization)
$headers.Add("Dropbox-API-Arg", $arg)
$headers.Add("Content-Type", 'application/json')
 
$resp = try { Invoke-RestMethod -Method Delete -Uri https://api.dropboxapi.com/2/files/delete_v2 -Headers $headers } catch { $_.Exception.Response }

Second:

$TargetFilePath = "/20181008"
$DropBoxAccessToken = "<access-token>"

$arg = '{ "path": "' + $TargetFilePath + '" }'
$authorization = "Bearer " + $DropBoxAccessToken
 
$headers = New-Object "System.Collections.Generic.Dictionary[[String],[String]]"
$headers.Add("Authorization", $authorization)
$headers.Add("Dropbox-API-Arg", $arg)
$headers.Add("Content-Type", 'application/json')

try {
        $result = Invoke-RestMethod -Method Delete -Uri https://api.dropboxapi.com/2/files/delete_v2 -Headers $headers
}
catch {
        $result = $_.Exception.Response.GetResponseStream()
        $reader = New-Object System.IO.StreamReader($result)
        $reader.BaseStream.Position = 0
        $reader.DiscardBufferedData()
        $responseBody = $reader.ReadToEnd();
}

I must be formatting this wrong?

I believe your second version is closer, as it actually reads the body. (The first one doesn't appear to.)

In both though, you're not actually printing out the result or saving it anyway. E.g., something like:

Write-Output $responseBody

I get output now, thanks.

Your request's HTTP request method is "DELETE", which is not supported by the Dropbox API v2.

That output indicates that the issue is that you're using the "DELETE" method, which isn't allowed. The API expect the "POST" method. 

That's presumably due to the "-Method Delete" in your code; for POST you would likely need to set "-Method Post".

This is the response when I changed Delete to Post.

Error in call to API function "files/delete:2": Unexpected HTTP headers: "Dropbox-Api-Arg"

When removing the line $headers.Add("Dropbox-API-Arg", $arg) the response is:

Error in call to API function "files/delete:2": request body: could not decode input as JSON

That is also expected, as this endpoint requires the parameters be sent as JSON in the request body. Please refer to my earlier comment for links to documentation for this.