Metrics & Telemetry
Metrics & Telemetry
Section titled “Metrics & Telemetry”Record application metrics using counters, gauges, and histograms.
Loading
Section titled “Loading”local metrics = require("metrics")Counters
Section titled “Counters”Increment Counter
Section titled “Increment Counter”metrics.counter_inc("requests_total", {method = "POST"})| Parameter | Type | Description |
|---|---|---|
name | string | Metric name |
labels | table? | Label key-value pairs |
Returns: boolean, error
Add to Counter
Section titled “Add to Counter”metrics.counter_add("bytes_total", 1024, {direction = "out"})| Parameter | Type | Description |
|---|---|---|
name | string | Metric name |
value | number | Value to add |
labels | table? | Label key-value pairs |
Returns: boolean, error
Gauges
Section titled “Gauges”Set Gauge
Section titled “Set Gauge”metrics.gauge_set("queue_depth", 42, {queue = "emails"})| Parameter | Type | Description |
|---|---|---|
name | string | Metric name |
value | number | Current value |
labels | table? | Label key-value pairs |
Returns: boolean, error
Increment Gauge
Section titled “Increment Gauge”metrics.gauge_inc("connections", {pool = "db"})| Parameter | Type | Description |
|---|---|---|
name | string | Metric name |
labels | table? | Label key-value pairs |
Returns: boolean, error
Decrement Gauge
Section titled “Decrement Gauge”metrics.gauge_dec("connections", {pool = "db"})| Parameter | Type | Description |
|---|---|---|
name | string | Metric name |
labels | table? | Label key-value pairs |
Returns: boolean, error
Histograms
Section titled “Histograms”Record Observation
Section titled “Record Observation”metrics.histogram("duration_seconds", 0.123, {method = "GET"})| Parameter | Type | Description |
|---|---|---|
name | string | Metric name |
value | number | Observed value |
labels | table? | Label key-value pairs |
Returns: boolean, error
Errors
Section titled “Errors”| Condition | Kind | Retryable |
|---|---|---|
| Collector not available | errors.INTERNAL | no |
See Error Handling for working with errors.