feat(grouping): Add better support for native fingerprinting/grouping use-cases

[mujacica]

• Added support for fingerprinting based on the thread info
  thread.name:MainThread type:RuntimeError -> main-thread-error
thread.crashed:true -> crashed-thread

• Added support sibling matching for fingerprinting
  [ function:handler ] | function:process -> handler-process

• Added support for thread info in client-side fingerprinting
  Sentry.setFingerprint(["{{ thread.name }}", "{{ transaction }}"]);
sentry_sdk.set_fingerprint(["{{ thread.name }}", "database-error"])

[codecov]

Codecov Report

❌ Patch coverage is 93.37748% with 10 lines in your changes missing coverage. Please review.
✅ All tests successful. No failed tests found.

Files with missing lines	Patch %	Lines
src/sentry/grouping/fingerprinting/rules.py	86.84%	5 Missing ⚠️
src/sentry/grouping/fingerprinting/matchers.py	94.64%	3 Missing ⚠️
src/sentry/grouping/fingerprinting/parser.py	91.30%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff            @@
##           master   #102653    +/-   ##
=========================================
  Coverage   80.41%    80.42%            
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  Files        9393      9394     +1     
  Lines      403390    403628   +238     
  Branches    25923     25923            
=========================================
+ Hits       324400    324613   +213     
- Misses      78550     78575    +25     
  Partials      440       440            

[lobsterkatie]

This looks good!

My only question is if the tests would be better as snapshot tests, because then we'd be able to do versioned tests, the same way we do with enhancement rules. It would also allow you to get rid of some of the boilerplate in these tests. WDYT?

[getsantry]

This pull request has gone three weeks without activity. In another week, I will close it.

But! If you comment or otherwise update it, I will reset the clock, and if you add the label WIP, I will leave it alone unless WIP is removed ... forever!

---

"A weed is but an unloved flower." ― Ella Wheeler Wilcox 🥀

[cursor]

Bug: Thread matcher JSON round-trip fails on deserialization

The thread matchers cannot be properly deserialized from JSON after serialization. The _to_config_structure method serializes using the internal key (e.g., "thread_name"), but _from_config_structure passes this key directly to FingerprintMatcher.__init__, which expects the external key (e.g., "thread.name") to look up in MATCHERS. Since "thread_name" is not a key in MATCHERS (only a value), deserialization fails with InvalidFingerprintingConfig. This affects all new thread matchers (thread.id, thread.name, thread.state, thread.crashed, thread.current) and breaks any workflow that saves fingerprinting configs to JSON and loads them back, like to_json() followed by from_json().

src/sentry/grouping/fingerprinting/matchers.py#L140-L174

sentry/src/sentry/grouping/fingerprinting/matchers.py

Lines 140 to 174 in 91a01bb

	def _to_config_structure(self) -> list[str]:
	key = self.key
	if self.negated:
	key = "!" + key
	return [key, self.pattern]
	@classmethod
	def _from_config_structure(
	cls, matcher: list[str]
	) -> FingerprintMatcher | CallerMatcher | CalleeMatcher:
	key, pattern = matcher
	# Check for sibling matcher syntax
	# CallerMatcher: [key]| or [!key]|
	# CalleeMatcher: |[key] or |[!key]
	if key.startswith("[") and key.endswith("]|"):
	inner_key = key[1:-2] # Remove [ and ]|
	negated = inner_key.startswith("!")
	inner_key = inner_key.lstrip("!")
	inner_matcher = cls(inner_key, pattern, negated)
	return CallerMatcher(inner_matcher)
	if key.startswith("|[") and key.endswith("]"):
	inner_key = key[2:-1] # Remove |[ and ]
	negated = inner_key.startswith("!")
	inner_key = inner_key.lstrip("!")
	inner_matcher = cls(inner_key, pattern, negated)
	return CalleeMatcher(inner_matcher)
	# Regular matcher
	negated = key.startswith("!")
	key = key.lstrip("!")
	return cls(key, pattern, negated)

 

---

[getsantry]

This pull request has gone three weeks without activity. In another week, I will close it.

But! If you comment or otherwise update it, I will reset the clock, and if you add the label WIP, I will leave it alone unless WIP is removed ... forever!

---

"A weed is but an unloved flower." ― Ella Wheeler Wilcox 🥀

[mujacica]

Hey @lobsterkatie - any more info/insights for this one - I would like to slowly start integrating this. You mentioned snapshot testing as a potential improvement - I tried it out but without a lot of success. Is that blocking for the merge?