feat: Adds new configuration options to add custom tags (labels) to logs

lib/aggregators/log-aggregator.js

@@ -6,6 +6,7 @@
 'use strict'
 
 const logger = require('../logger').child({ component: 'logs_aggregator' })
+const { isLogLabelingEnabled } = require('../../lib/util/application-logging')
 const EventAggregator = require('./event-aggregator')
 
 const NAMES = require('../metrics/names')
@@ -57,12 +58,22 @@ class LogAggregator extends EventAggregator {
     }
 
     const commonAttrs = this.agent.getServiceLinkingMetadata()
-    return [
+
+    const payload = [
       {
         common: { attributes: commonAttrs },
         logs: formattedLogs
       }
     ]
+
+    if (isLogLabelingEnabled(this.agent.config)) {
+      payload[0].common.attributes = {
+        ...payload[0].common.attributes,
+        ...this.agent.config.filteredLabels
+      }
+    }
+
+    return payload
   }
 
   add(logLine) {

lib/config/index.js

@@ -24,6 +24,7 @@ const harvestConfigValidator = require('./harvest-config-validator')
 const mergeServerConfig = new MergeServerConfig()
 const { boolean: isTruthular } = require('./formatters')
 const configDefinition = definition()
+const parseLabels = require('../util/label-parser')
 
 /**
  * CONSTANTS -- we gotta lotta 'em
@@ -195,9 +196,37 @@ function Config(config) {
 
   // 9. Set instance attribute filter using updated context
   this.attributeFilter = new AttributeFilter(this)
+
+  const excludeList = this.application_logging.forwarding.labels.exclude
+
+  // 10. Setup labels after filtering for exclusions
+  if (excludeList.length > 0) {
+    this.application_logging.forwarding.labels.exclude = excludeList.map((k) => k.toLowerCase())
+  }
+
+  this._filterLabels()
 }
 util.inherits(Config, EventEmitter)
 
+/**
+ * Compares the labels list to the excluded label list and removes any labels that need to be excluded.
+ * Then prefixing each label with "tags."
+ */
+Config.prototype._filterLabels = function filterLabels() {
+  const configuredLabels = parseLabels(this.labels)
+
+  const filteredLabels = {}
+
+  configuredLabels.forEach((label) => {
+    if (
+      !this.application_logging.forwarding.labels.exclude.includes(label.label_type.toLowerCase())
+    ) {
+      filteredLabels[`tags.${label.label_type}`] = label.label_value
+    }
+  })
+  this.filteredLabels = filteredLabels
+}
+
 /**
  * Because this module and logger depend on each other, the logger needs
  * a way to inject the actual logger instance once it's constructed.

lib/util/application-logging.js

@@ -75,6 +75,18 @@ utils.isLogForwardingEnabled = function isLogForwardingEnabled(config, agent) {
   )
 }
 
+/**
+ * Checks if application_logging.forwarding.labels is enabled and there are labels in config
+ *
+ * @param {object} config agent config
+ * @returns {boolean} is labeling enabled
+ */
+utils.isLogLabelingEnabled = function isLogLabelingEnabled(config) {
+  return !!(
+    config.application_logging.forwarding.labels.enabled && Object.keys(config.labels).length > 0
+  )
+}
+
 /**
  * Increments both `Logging/lines` and `Logging/lines/<level>` call count
  *