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Update rawbody.go - Fix broken encoding due to mishandling Content-Type #35

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Update rawbody.go - Fix broken encoding due to mishandling Content-Type #35

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f81e182
Update rawbody.go - Fix broken encoding due to mishandling Content-Type
gunir Jan 15, 2026
0725a57
Update rawbody.go - Fix some variable mismatches
gunir Jan 15, 2026
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15 changes: 12 additions & 3 deletions httprewrite/rawbody.go
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Original file line number Diff line number Diff line change
Expand Up @@ -80,10 +80,13 @@ func getRawBodyReader(res *http.Response) (body io.ReadCloser, mimeType string,
contentType := res.Header.Get("Content-Type")
mimeType, params, err := mime.ParseMediaType(contentType)
if err != nil {
return nil, "", fmt.Errorf("parse content type %q: %v", contentType, err)
mimeType = "text/plain" // Fallback
}
if encoding == "" && strings.ToLower(params["charset"]) == "utf-8" {
// The body is already UTF-8 encoded and not compressed.

// [FIX 1] Treat missing charset as UTF-8 (Modern Web Default)
// If encoding is empty and no charset is specified, pass the body through raw.
charsetParam := strings.ToLower(params["charset"])
if encoding == "" && (charsetParam == "utf-8" || charsetParam == "") {
return res.Body, mimeType, nil
}

Expand All @@ -92,6 +95,12 @@ func getRawBodyReader(res *http.Response) (body io.ReadCloser, mimeType string,
return nil, "", fmt.Errorf("create decompressed reader for encoding %q: %v", encoding, err)
}

// [FIX 2] If we reach here (because of compression), ensure we don't
// let charset.NewReader default to Windows-1252 if charset is missing.
if charsetParam == "" {
contentType = mimeType + "; charset=utf-8"
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@anfragment anfragment Jan 17, 2026

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This will unfortunately prevent charset.NewReader from performing a prescan algorithm to find a potential <meta charset> element, see:

}

decodedReader, err := charset.NewReader(decompressedReader, contentType)
if err != nil {
decompressedReader.Close()
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