fix(transport): Handle HTTP 413 with actionable log and use send_error for HTTP errors

[adinauer]

Relay now returns HTTP 413 instead of HTTP 400 for oversized envelopes
(relay#5474). Previously
the SDK treated 413 like any other 4xx error with a generic log message,
giving users no indication of why their data was dropped.

This adds a specific, actionable error message when receiving HTTP 413,
suggesting users reduce the size of events, breadcrumbs, or attachments,
and pointing them to the SentryOptions.onOversizedEvent callback.

Also switches the client report discard reason for all HTTP 4xx/5xx errors
(except 429) from network_error to send_error, matching the
client reports spec and
aligning with sentry-python and sentry-cocoa. network_error is now
reserved for actual connectivity failures (IOException, transport gate
not connected).

Changes:

• DiscardReason.java — Added SEND_ERROR("send_error")
• HttpConnection.java — 413-specific log message in readAndLog()
• AsyncHttpTransport.java — 413-specific log message + SEND_ERROR for all HTTP errors
• ApacheHttpClientTransport.java — Same as above

Fixes #5050

[github-actions]

🚨 Detected changes in high risk code 🚨

High-risk code has higher potential to break the SDK and may be hard to test. To prevent severe bugs, apply the rollout process for releasing such changes and be extra careful when changing and reviewing these files:

• sentry-apache-http-client-5/src/main/java/io/sentry/transport/apache/ApacheHttpClientTransport.java
• sentry/src/main/java/io/sentry/transport/AsyncHttpTransport.java
• sentry/src/main/java/io/sentry/transport/HttpConnection.java

[github-actions]

Semver Impact of This PR

🟢 Patch (bug fixes)

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Bug Fixes 🐛

• (transport) Handle HTTP 413 with actionable log and use send_error for HTTP errors by adinauer in #5115

• Safe unregister SystemEventsBroadcastReceiver by kollesnica1337 in #5106

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_{🤖 This preview updates automatically when you update the PR.}

[github-actions]

🚨 Detected changes in high risk code 🚨

High-risk code has higher potential to break the SDK and may be hard to test. To prevent severe bugs, apply the rollout process for releasing such changes and be extra careful when changing and reviewing these files:

• sentry-apache-http-client-5/src/main/java/io/sentry/transport/apache/ApacheHttpClientTransport.java
• sentry/src/main/java/io/sentry/transport/AsyncHttpTransport.java
• sentry/src/main/java/io/sentry/transport/HttpConnection.java

[cursor]

Cursor Bugbot has reviewed your changes and found 1 potential issue.

^{Bugbot Autofix is OFF. To automatically fix reported issues with Cloud Agents, enable Autofix in the Cursor dashboard.}

[cursor]

Duplicate 413 error message logged in AsyncHttpTransport path

Low Severity

When AsyncHttpTransport handles a 413 response, the identical actionable error message gets logged twice. AsyncHttpTransport.send() calls connection.send() which calls HttpConnection.readAndLog() — that logs the 413-specific message first. Then control returns to AsyncHttpTransport, which logs the same message again. Before this change, the two log sites used different message strings, so duplication was less noticeable. Now both emit the same long user-facing guidance, which is confusing.

Additional Locations (1)

• sentry/src/main/java/io/sentry/transport/HttpConnection.java#L182-L191

 

[github-actions]

Performance metrics 🚀

	Plain	With Sentry	Diff
Startup time	328.61 ms	384.38 ms	55.77 ms
Size	1.58 MiB	2.29 MiB	720.01 KiB

Baseline results on branch: main

Startup times

Revision	Plain	With Sentry	Diff
d15471f	361.89 ms	378.07 ms	16.18 ms
6edfca2	305.52 ms	432.78 ms	127.26 ms
ed33deb	337.52 ms	484.06 ms	146.54 ms
f064536	349.86 ms	417.66 ms	67.80 ms
d217708	409.83 ms	474.72 ms	64.89 ms
23d6b12	354.10 ms	408.38 ms	54.28 ms
ad8da22	362.98 ms	453.94 ms	90.96 ms
ee747ae	374.71 ms	455.18 ms	80.47 ms
33a08cc	267.08 ms	340.45 ms	73.37 ms
2124a46	319.19 ms	415.04 ms	95.85 ms

App size

Revision	Plain	With Sentry	Diff
d15471f	1.58 MiB	2.13 MiB	559.54 KiB
6edfca2	1.58 MiB	2.13 MiB	559.07 KiB
ed33deb	1.58 MiB	2.13 MiB	559.52 KiB
f064536	1.58 MiB	2.20 MiB	633.90 KiB
d217708	1.58 MiB	2.10 MiB	532.97 KiB
23d6b12	1.58 MiB	2.10 MiB	532.31 KiB
ad8da22	1.58 MiB	2.29 MiB	719.83 KiB
ee747ae	1.58 MiB	2.10 MiB	530.95 KiB
33a08cc	1.58 MiB	2.12 MiB	555.28 KiB
2124a46	1.58 MiB	2.12 MiB	551.51 KiB