Modules
Elixir error reporting client for ForgeOps
A bounded, in-order trail of what happened right before an exception: the automatic
"controller"/"query"/"job" entries ForgeOpsTracker.Integrations.Phoenix/Ecto/Oban
record (see each one's own module doc), plus anything added by hand via
ForgeOpsTracker.add_breadcrumb/4. Ported from
gems/forge_ops_tracker/lib/forge_ops_tracker/breadcrumb_buffer.rb: a ring buffer capped at
Configuration.t/0's own max_breadcrumbs, oldest entry dropped once full.
Delivers one payload over HTTP via :httpc (Erlang's own HTTP client, part of the :inets
application bundled with every OTP install: no Hex dependency needed, same reasoning as
net/http in the Ruby gem and java.net.http.HttpClient in the Java/Kotlin clients). Every
failure mode (DNS, connection, timeout, TLS, a non-2xx response) is caught here and turned
into false rather than a raised exception, since a broken or unreachable tracker must never be
able to break the host app.
Holds a single ForgeOps DSN plus everything else the client needs to build and deliver events.
Mirrors gems/forge_ops_tracker's Configuration: a single DSN string carries
both the ingestion URL and the project's api_key: https://<api_key>@host/api/v1/events.
A small bounded queue, processed one event at a time, so delivery never blocks the caller that
raised the error. The BEAM equivalent of the Ruby/Python/Java clients' own background-thread-
backed queue: except here the "queue manager" is an ordinary supervised GenServer (started
once, see ForgeOpsTracker.Application, not spun up lazily on first push, since BEAM processes
are cheap enough that there's no meaningful cost to keeping one alive idle) and each actual
delivery runs in its own short-lived Task, not inline in the GenServer's own callback.
Turns an exception/reason plus an Elixir stacktrace into the payload shape the ingestion API
expects. Unlike the Ruby/PHP/JS clients in this repo, backtrace parsing here is not a regex
over a string: __STACKTRACE__ is already a structured list of {module, function, arity, location} tuples (location a keyword list with :file/:line), the same situation Python's
traceback module and Java's Throwable.getStackTrace() put those clients in. Verified
directly against a real raised-and-rescued exception's __STACKTRACE__ before relying on this
shape, not assumed from documentation alone.
Buckets a single duration into one of a fixed set of latency-range labels, the building block
ForgeOpsTracker.PerformanceFlusher uses to accumulate an approximate distribution (not just
count/sum/max) alongside every {transaction_name, kind} bucket it already tallies. The server
merges these counts across matching samples at read time and walks cumulative counts to
approximate a percentile, accurate to the bucket width: this SDK never stores the raw duration
list a true percentile would need. Ported from
gems/forge_ops_tracker/lib/forge_ops_tracker/histogram_bucketer.rb.
Times every query a given Ecto.Repo runs, kind: "query". Call once at startup, passing the
repo module itself
Times every Oban job, kind: "job", and reports a genuinely failed job (retries exhausted, or
the worker explicitly gave up) the same way an unhandled exception anywhere else already is. Call
once at startup
Times every matched Phoenix route, kind: "controller". Call once at startup, e.g.
application.ex's own start/2, before the rest of the supervision tree starts
Automatically identifies the affected user for every error reported during this request, when
conn.assigns[:current_user] is present: the de facto convention across Phoenix's own generated
auth (mix phx.gen.auth), Pow, and most hand-rolled Guardian setups alike, since Phoenix itself
(unlike Rails/Devise) has no single dominant auth library this could depend on directly.
Reports any process crash anywhere in the whole BEAM VM, with zero further wiring needed:
attached via :logger.add_handler/3 (see ForgeOpsTracker.install_handlers/0), a standard
:logger_handler behaviour implementation, the same technique other logger-integrated error
trackers in the Elixir ecosystem use for the same purpose.
Collects individual ForgeOpsTracker.capture_metric/2 / capture_infrastructure_metric/3 calls
and periodically flushes them as one batch, rather than one network call per capture. Unlike
ForgeOpsTracker.PerformanceFlusher this keeps a list of individually meaningful entries
instead of summing them into buckets: a customer's own signup or payment is exactly the kind of
thing they will want a genuinely accurate count/sum of later, so the server stores one row per
entry as-is. Ported from gems/forge_ops_tracker's metric_buffer.rb and
infrastructure_metric_buffer.rb, which are the same class twice; here it is one GenServer
started twice under ForgeOpsTracker.Application (:custom and :infrastructure), each
registered under its own name.
Times every request/job/query in-process, bucketed by {transaction_name, kind} (kind is
"controller"/"job"/"query", see the ForgeOpsTracker.Integrations.* modules, each a
different telemetry source), and periodically flushes each distinct bucket as one small
aggregate report, rather than one network call per event. Mirrors gems/forge_ops_tracker's own
PerformanceFlusher exactly in shape (the aggregation itself: count + duration sum + max over a
period), but started once as a supervised GenServer (a fourth child of
ForgeOpsTracker.Application, alongside Configuration and DeliveryQueue) rather than lazily
spawning a background thread on first use: Elixir has no per-request-process fork boundary to
dodge the way Ruby's Puma/Passenger workers do (the actual reason that gem starts lazily), and
BEAM processes are cheap enough that there's no cost to just always running one.
Redacts likely-sensitive content out of a payload before it ever leaves this process: the
same patterns ForgeOps itself applies again on arrival (defense in depth: this layer keeps the
data off the wire and out of any request logging in between; the server-side layer is what
actually protects the database, and doesn't depend on every reporting app running an up-to-date
version of this client). Ported from
gems/forge_ops_tracker/lib/forge_ops_tracker/pii_scrubber.rb: same key list, same 8 regex
patterns, unmodified from the Ruby original: Elixir's Regex is Erlang's :re module, itself a
PCRE implementation, so unlike this repo's own C client (which had to adapt every pattern to
POSIX Extended Regular Expressions: no \d/\s/\b), nothing here needed translating.
A low-cardinality bucket name for a database query, for the same reason every other SDK's own
transaction_name never uses the raw SQL text directly: every slightly different query shape
would become its own bucket, and raw SQL is a real, if usually parameterized, risk of leaking a
literal value.
Ties Configuration, EventBuilder, and DeliveryQueue together into the one thing callers actually
need: report an exception. Mirrors every other SDK's own Reporter/ErrorSubscriber: never
raises. An error reporter that itself raises while reporting an error is the worst possible
failure mode, so every path here is wrapped to guarantee this never propagates back into the
caller (or, when called from ForgeOpsTracker.LoggerHandler, back into the :logger pipeline
itself, which would be just as bad).
Finds the SQL behind a database error and reduces it to something safe to send: the names of
the stored procedures, tables and views it touched, and (only if
capture_sql_statement is on) the statement itself with every string and number replaced by
?. Ported from gems/forge_ops_tracker's SqlStatement, which is itself ported from the
server's own SqlStatementMasker/SqlObjectExtractor: same rules everywhere, and the server
applies them again on arrival, so a difference here can only ever mean less is masked
client-side, never that something unmasked gets stored.
One trace's worth of spans (a request's own call tree), kept in the calling process's own
process dictionary: the same isolation boundary ForgeOpsTracker.set_user/1 and
ForgeOpsTracker.add_breadcrumb/4 already use, and for the same reason (Phoenix and Oban both
run one unit of work in one process). Not something app code normally calls directly; see
ForgeOpsTracker.span/4 and ForgeOpsTracker.record_span/5.