Hydra Log

A minimal PSR-3 logger that writes one plain-text line per record to a writable stream. No handlers, no processors, no formatters config — Hydra's logging is a single deliberate class, the data-layer-style "ship the verb" of logging.

How it works

StreamLogger is constructed with an already-open, writable stream — a file handle, php://stderr, php://memory in tests. Sink selection is the caller's concern: the class only formats and writes. The app's service provider is what opens LOG_PATH (falling back to stderr when the path is unwritable) and hands the stream in.

use Hydra\Log\StreamLogger;

$logger = new StreamLogger(fopen('php://stderr', 'w'));
$logger->info('request handled', ['method' => 'GET', 'status' => 200]);
// [2026-06-20T01:44:06+00:00] INFO: request handled {"method":"GET","status":200}

Each record renders as [ISO-8601] LEVEL: message <context>:

• Placeholders — {key} tokens are interpolated from context per PSR-3. Substitution is keyed on value type, not truthiness, so 0, '' and false render rather than vanish. A placeholder with no usable value is left intact.
• Leftover context is appended as JSON. A Throwable under the conventional exception key is rendered as a readable class/message/file/line + trace instead.

Failures never escalate

A broken sink (closed stream, full disk) must not take the application down with it: the write is @fwrite and guarded by is_resource. Logging is best-effort by design.

What it deliberately is not

No log rotation, no level filtering, no multiple sinks. Those are the app's job if it ever needs them — bind a different Psr\Log\LoggerInterface implementation (Monolog, a fan-out logger) in the service provider and every consumer follows, because consumers depend on the PSR-3 interface, never on this class.