Refactor pino instrumentation

[jsumners-nr]

See the conversation in #2421. Basically, the following needs to be refactored in order to satisfy the SonarQube linter:

node-newrelic/lib/instrumentation/pino/pino.js

Lines 18 to 95 in 599072b

	// eslint-disable-next-line sonarjs/cognitive-complexity
	module.exports = function instrument(shim, tools) {
	const pinoVersion = shim.pkgVersion
	if (semver.lt(pinoVersion, '7.0.0')) {
	shim.logger.debug('Instrumentation only supported on pino >=7.0.0.')
	return
	}
	const agent = shim.agent
	const config = agent.config
	if (!isApplicationLoggingEnabled(config)) {
	shim.logger.debug('Application logging not enabled. Not instrumenting pino.')
	return
	}
	const metrics = agent.metrics
	createModuleUsageMetric('pino', metrics)
	const symbols = shim.require('./lib/symbols')
	shim.wrap(tools, 'asJson', function wrapJson(shim, asJson) {
	/**
	* Wraps function in pino that is used to construct/serialize a log
	* line to json
	*
	* @param {object} obj data from mixins
	* @param {string} msg message of log line
	* @param {number} num log level as number
	* @param {string} time formatted snippet of json with time(`,"time":<unix time>`)
	* @returns {string} serialized log line
	*/
	return function wrappedAsJson() {
	const args = shim.argsToArray.apply(shim, arguments)
	const level = this?.levels?.labels?.[args[2]]
	// Pino log methods accept a singular object (a merging object) that can
	// have a `msg` property for the log message. In such cases, we need to
	// update that log property instead of the second parameter.
	const useMergeObj = args[1] === undefined && Object.hasOwn(args[0], 'msg')
	if (isMetricsEnabled(config)) {
	incrementLoggingLinesMetrics(level, metrics)
	}
	if (isLocalDecoratingEnabled(config)) {
	if (useMergeObj === true) {
	args[0].msg += agent.getNRLinkingMetadata()
	} else {
	args[1] += agent.getNRLinkingMetadata()
	}
	}
	/**
	* must call original asJson to allow pino
	* to construct the entire log line before we
	* add to the log aggregator
	*/
	const logLine = asJson.apply(this, args)
	if (isLogForwardingEnabled(config, agent)) {
	const chindings = this[symbols.chindingsSym]
	const formatLogLine = reformatLogLine({
	msg: useMergeObj === true ? args[0].msg : args[1],
	logLine,
	agent,
	chindings,
	level,
	logger: shim.logger
	})
	agent.logs.add(formatLogLine)
	}
	return logLine
	}
	})
	}

Prior to opening the PR for review, I attempted:

function instrument(shim, tools) {
	// snip
	shim.wrap(tools, 'asJson', function wrapJson(shim, asJson) {
		return wrappedAsJson.bind({ shim, agent, symbols, asJson, metrics, config})
	}
}

function wrappedAsJson() {
	const { shim, agent, symbols, asJson, metrics, config } = this
	// implementation
}

But that won't work because wrappedAsJson needs this to be bound to the instrumented instance of Pino.

[workato-integration]

https://new-relic.atlassian.net/browse/NR-298951