middleware: fix httpFancyWriter.ReadFrom double-counting bytes with Tee#1085
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alliasgher wants to merge 1 commit intogo-chi:masterfrom
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middleware: fix httpFancyWriter.ReadFrom double-counting bytes with Tee#1085alliasgher wants to merge 1 commit intogo-chi:masterfrom
alliasgher wants to merge 1 commit intogo-chi:masterfrom
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When a Tee writer is set, ReadFrom calls io.Copy(&f.basicWriter, r),
which routes each write through basicWriter.Write. Write already
increments basicWriter.bytes, so the line
f.basicWriter.bytes += int(n)
that followed the io.Copy double-counted every byte, causing
BytesWritten() to return twice the actual value.
Remove the redundant addition. The non-tee path is unaffected because
it delegates to the underlying ResponseWriter's ReaderFrom (bypassing
Write) and must still add n itself.
Fixes go-chi#1067
Signed-off-by: alliasgher <alliasgher123@gmail.com>
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Summary
httpFancyWriter.ReadFrominmiddleware/wrap_writer.godouble-countedBytesWritten()when a Tee writer was set.When
tee != nil, the code calledio.Copy(&f.basicWriter, r), which routes every write throughbasicWriter.Write.Writealready incrementsbasicWriter.bytes. After the copy returned, the old code then did:…adding
na second time. The result:BytesWritten()returned exactly twice the actual number of bytes transferred.Fix
Remove the redundant
f.basicWriter.bytes += int(n)line in the tee branch. The non-tee path (which delegates to the underlyingReaderFrom, bypassingWrite) is not affected and still needs to addnitself.Test
Added
TestHttpFancyWriterReadFromByteCountWithTeethat reproduces the original bug (it fails before the fix and passes after). The full middleware test suite still passes.Fixes #1067