# Changelog

## 0.9.0

- Distributed tracing across services, using the W3C Trace Context standard (`traceparent`). Every request that passes through `PSGIPerformance` or `Dancer2Performance` now gets a trace id; one that arrives with a valid `traceparent` header continues that trace, and its root span points at the caller's span. A missing or malformed header starts a fresh trace. `ForgeOps::Tracker::current_trace_id()` returns it, and `start_trace($traceparent)` continues one for work that isn't a request.
- Every error reported during a request now says where it happened: `trace_id`, plus, under Dancer2, `transaction_name` (the same `GET /users/:id` name performance samples and traces already use) and `endpoint` (the HTTP method plus the route pattern as declared; never the raw path). Set as soon as Dancer2 has matched the route, so an error reported from inside a route already has them. Plain PSGI has no route pattern, so it sends only `trace_id` unless the app names the request with the new `set_request_route($transaction_name, $endpoint)`. Left out outside a request. Structured fields, so they're never PII-scrubbed.
- `ForgeOps::Tracker::http_span($method, $url, sub { my ($headers) = @_; ... }, data => {})` records an outgoing HTTP call as an `http` span named after the method and host, and hands your code the `traceparent` header to add to it; its parent id is the span's own id, so the called service's root span nests under it. This client doesn't instrument an HTTP client itself. New `propagate_traces` (default 1) and `trace_propagation_targets` (default undef, meaning every host; or an arrayref of host strings, each matching that host and its subdomains, and/or `qr//` regular expressions) control where the header goes.
- An errored request's trace is always sent, however fast it was: an error reported while the request ran, or one escaping it. A Dancer2 route that dies now has its trace finished and sent (Dancer2 never runs `after_request` for it, so before this it was never sent at all). Fast, successful requests are unchanged.
- An error escaping a request keeps its trace id, transaction name, endpoint, user and breadcrumbs when it's reported after the performance integration has already finished the request: `Integrations::PSGI` enabled outside `PSGIPerformance` (the documented order), or `Integrations::Dancer2` loaded after `Dancer2Performance`.
- With `track_tracing => 0`, requests still get a trace id (attached to errors and handed out by `http_span`, since that is also what links errors across services); only span reporting stops.
- Trace and span ids were already W3C shaped (32 and 16 lowercase hex characters); they are now also guaranteed never to be all zeros, the one value the standard reserves as invalid.

This client has earlier CPAN releases (see `$ForgeOps::Tracker::VERSION`'s history in source control), but no `CHANGELOG.md` existed for it before this entry; like `sdks/java`'s, it starts here without backfilling earlier versions.