fix: decompress gzip/deflate/br responses in parseURL() - #306
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pratik-desgn wants to merge 1 commit into
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fix: decompress gzip/deflate/br responses in parseURL()#306pratik-desgn wants to merge 1 commit into
pratik-desgn wants to merge 1 commit into
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parseURL() reads the raw HTTP response body as text via res.on('data'),
so a server that returns a compressed body (with or without an
Accept-Encoding request header - which rss-parser never sent) produces
garbage bytes that the XML parser rejects with
"Non-whitespace before first tag" (rbren#280).
Now requests advertise Accept-Encoding: gzip, deflate, br, and any
response actually returned with a Content-Encoding header gets piped
through the matching zlib decompression stream before being read as
text, regardless of what was requested - matching how fetch()/browsers
already handle this.
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Summary
Fixes #280.
parseURL()never sends anAccept-Encodingheader, and reads the raw HTTP response body directly as text (res.on('data')). Per RFC 7231 §5.3.4, a server is allowed to compress a response even without anAccept-Encodingrequest header - and as the issue reports, some servers do this unconditionally regardless of what's requested. When that happens, rss-parser feeds raw gzip bytes to the XML parser and fails withNon-whitespace before first tag.Browsers and
fetch()handle this by transparently decompressing based on the response'sContent-Encoding, independent of what was requested. This PR does the same.Changes
parseURL()now sendsAccept-Encoding: gzip, deflate, brby default (inDEFAULT_HEADERS), for better compliance and so compliant servers can save bandwidth.Content-Encoding: gzip/deflate/brheader, the body is piped through the matchingzlibdecompression stream before being read as text - covering the case in the issue where the server ignoresAccept-Encodingentirely.Test plan
Content-Encoding: gzipheader and no request for it, and asserts it parses correctly. Confirmed it fails with the exactNon-whitespace before first tagerror from the issue when run against the old code, and passes with the fix.