fix(webhook): preserve data.id case in signature manifest#118
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The manifest was lowercasing data.id before computing the HMAC, but MercadoPago signs the notification using the original casing. This caused signature validation to fail whenever data.id contained uppercase letters.
luismeli10 (luismeli10)
approved these changes
Jun 24, 2026
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Problem
The
WebhookSignatureValidatorwas calling.lower()ondata_idbefore building the HMAC manifest. MercadoPago signs webhook notifications using the original casing ofdata.id, so any notification with uppercase or mixed-case identifiers would fail validation withSignatureMismatch.Fix
Remove the
.lower()call in_build_manifestso the value is included exactly as received. The docstring is updated accordingly.Testing
Verified manually with
data.idvalues in uppercase (ORDER123), lowercase (order123), and mixed case (oRdEr) — all pass when the signature was generated with the same casing.