Logflare / logflare / 9d4eae2d5cd011e9afd7c4f7de82922955d8ea00

82%

Build Type

push

github

Committed by web-flow

Commit Message

fix(http): prevent duplicate transport-owned headers (#3567)

* fix(webhook): prevent duplicate transport-owned headers in HTTP backends

When a user supplies a Content-Type header on a webhook/log-drain backend,
Tesla's JSON middleware appended a second one and Tesla.put_headers/2 does not
dedupe, so requests went out with two Content-Type values. Receivers
concatenated them into an unparseable value and delivered an empty body.

Give transport-owned headers a single source instead of relying on header
ordering:

- Add Logflare.Backends.Adaptor.HttpBased.Headers with drop_reserved/2 and
  normalize_keys/1.
- WebhookAdaptor.Client.send/1 strips the reserved set per request: content-type
  only when the JSON middleware will encode the body (binary bodies keep a custom
  content-type), content-encoding when gzip is enabled.
- HttpBased.Client.new/1 strips content-encoding (gzip) and authorization
  (token/basic auth).
- WebhookAdaptor.cast_config/2 lowercases header keys so stored config cannot
  hold case-variant duplicates.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

* fix(otlp): drop user content-type owned by the request formatter

HttpBased.Client deliberately excluded content-type from its reserved
header set because the body is not known at client-build time, so it
could not tell whether Tesla.Middleware.JSON would encode and own it.
But OtlpAdaptor passes user-configured headers alongside ProtobufFormatter,
which always sets content-type to application/x-protobuf. A user-supplied
content-type therefore survived next to the formatter's, reintroducing the
duplicate-header failure mode for OTLP backends.

Let the formatter that owns the header declare it instead of having the
client guess what middleware will do:

- HttpBased.Client.reserved_header_names/1 folds in an optional
  reserved_headers/0 exported by the formatter module (handles both the
  module and {module, opts} forms).
- OtlpAdaptor.ProtobufFormatter and Sen... (continued)

Coverage Stats

30 of 33 new or added lines in 6 files covered. (90.91%)

7 existing lines in 4 files now uncovered.

13735 of 16828 relevant lines covered (81.62%)

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