datadog

datadog

Emits DogStatsD metrics (request.counter, request.latency, ingress.size, egress.size) for each request and ships accumulated batches to a Datadog agent over UDP. Place this node in the response pipeline, after the upstream node, so latency and status are captured.

:::note Deviation from other loggers Unlike the HTTP loggers, datadog does not ship JSON logs to an HTTP endpoint. It renders each buffered entry into DogStatsD metric lines and sends them as UDP datagrams via a tokio::net::UdpSocket (not the shared outbound HTTP client). Agent settings (host, port, namespace, constant_tags) live directly in this node's config. Because featherbit's shared log entry carries no route/service identifiers, prefer_name is accepted but has no effect and no route_name/service_name tags are emitted. :::

Configuration

Key	Type	Default	Description
host	string	127.0.0.1	Datadog agent address.
port	integer	8125	DogStatsD UDP port.
namespace	string	featherbit	Metric name prefix.
constant_tags	array	[]	Tags added to every metric.
include_path	bool	false	Add a path: tag.
include_method	bool	false	Add a method: tag.
prefer_name	bool	true	Accepted for config compatibility; no effect.
batch_max_size	integer	1000	Flush when the buffer reaches this many entries.
inactive_timeout	integer (s)	5	Flush after this idle period.
buffer_duration	integer (s)	60	Flush when the oldest buffered entry is this old.
max_retry_count	integer	0	Retries after a failed flush before dropping the batch.
retry_delay	integer (s)	1	Delay between retries.
max_pending_entries	integer	10000	Queue capacity; entries are dropped with a warning when full.

- id: metrics
  type: datadog
  config:
    host: 127.0.0.1
    port: 8125
    namespace: featherbit
    constant_tags: [source:featherbit]
    include_method: true

Behavior

The node is a pure passthrough: it never modifies the context and never fails, so only its success port is ever taken. push is fire-and-forget and never blocks the request path — when the queue is full, entries are dropped with a tracing::warn!. Each entry yields metric lines of the form namespace.metric:value|type|#tags; the entry's metrics are coalesced into one datagram (or split when they exceed the 8192-byte DogStatsD buffer). Sending runs on a background task; a mid-batch send failure retries only the undelivered tail.