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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Invoke-RestMethod Multipart/Form-Data Filename encoding with non-ascii chars","articleBody":"### Prerequisites\n\n- [X] Write a descriptive title.\n- [X] Make sure you are able to repro it on the [latest released version](https://github.com/PowerShell/PowerShell/releases)\n- [X] Search the existing issues.\n- [X] Refer to the [FAQ](https://github.com/PowerShell/PowerShell/blob/master/docs/FAQ.md).\n- [X] Refer to [Differences between Windows PowerShell 5.1 and PowerShell](https://docs.microsoft.com/powershell/scripting/whats-new/differences-from-windows-powershell).\n\n### Steps to reproduce\n\nI am using the invoke-restmethod to do a Multipart/Form-Data Submission using the -Form parameter.\r\nThe form date also includes a file.\r\n`$DocumentUploadForm = @{`\r\n           ` file        = Get-Item $DocumentFile`\r\n            `title       = \"$DocumentTitle\"`\r\n            \r\nWhen the filename contains just ascii chars the filename is encoded as expected in the request body.\r\nHowever when the filename contains non-ascii chars the filename is encoded as per RFC-1342 which is unexpected.\r\nI have compared the behavior to the CURL application and there the filename is encoded differently using unicode codepoints.\n\n### Expected behavior\n\n```console\nRequest Body for file with non-ascci chars in the filename:\r\n\r\n...\r\n--------------------------748339ec18b72df1\r\nContent-Disposition: form-data; name=\"file\"; filename=\"t\\xcc\\x88stfile.pdf\"\r\nContent-Type: application/pdf\r\n\r\n%PDF-1.7\r\n...\r\n\r\nRequest Body for file with only ascii chars in the filename:\r\n\r\n...\r\n--------------------------748339ec18b72df1\r\nContent-Disposition: form-data; name=\"file\"; filename=\"testfile.pdf\"\r\nContent-Type: application/pdf\r\n\r\n%PDF-1.7\r\n...\n```\n\n\n### Actual behavior\n\n```console\nRequest Body for file with non-ascci chars in the filename:\r\n\r\n...\r\n--------------------------748339ec18b72df1\r\nContent-Disposition: form-data; name=\"file\"; filename=\"=?utf-8?B?S3XMiG5kaWd1bmdfTXVzdGVybWFubl9NYXguVFRBXzIwMjNfMDFfMzAucGRm?=\"\r\nContent-Type: application/pdf\r\n\r\n%PDF-1.7\r\n...\n```\n\n\n### Error details\n\n```console\nThere is no error in the powershell, but the server does not accept the POST request containing this filename encoding.\r\nThe server does accept a the POST request created by CURL.\r\nThe only difference is the encoding auf the filename.\r\nEither with unicode codepoints or with RFC-1342\n```\n\n\n### Environment data\n\n```powershell\nName                           Value\r\n----                           -----\r\nPSVersion                      7.3.3\r\nPSEdition                      Core\r\nGitCommitId                    7.3.3\r\nOS                             Darwin 22.4.0 Darwin Kernel Version 22.4.0: Mon Mar  6 20:59:58 PST 2023; root:xnu-8796.101.5~3/RELEASE_ARM64_T6020\r\nPlatform                       Unix\r\nPSCompatibleVersions           {1.0, 2.0, 3.0, 4.0…}\r\nPSRemotingProtocolVersion      2.3\r\nSerializationVersion           1.1.0.1\r\nWSManStackVersion              3.0\n```\n\n\n### Visuals\n\n_No response_","author":{"url":"https://github.com/joergrenn","@type":"Person","name":"joergrenn"},"datePublished":"2023-04-05T15:38:36.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":17},"url":"https://github.com/19456/PowerShell/issues/19456"}