feat: Log base w/ configurable pid and hostname keys (#868)

* Log base w/ configurable pid and hostname keys

- `hostname` isn't always desireable and is somewhat inaccurate given
os.hostname is the pod name in kubernetes

* Documentation for configurable log base

charts/kubernetes-external-secrets/README.md

@@ -47,6 +47,8 @@ The following table lists the configurable parameters of the `kubernetes-externa
 | `env.AWS_INTERMEDIATE_ROLE_ARN`           | Specifies a role to be assumed before assuming role arn specified in external secrets                                             |                                       |
 | `env.LOG_LEVEL`                           | Set the application log level                                                                                                     | `info`                                |
 | `env.LOG_MESSAGE_KEY`                     | Set the key for log messages log text, for example when running on GCP it might be nice to set to `message`                       | `msg`                                 |
+| `env.LOG_BASE_PID_KEY`                    | Set the key for log messages process id                                                                                           | `pid`                                 |
+| `env.LOG_BASE_HOSTNAME_KEY`               | Set the key for log messages hostname, for example, you might choose to use `pod_name`                                            | `hostname`                            |
 | `env.USE_HUMAN_READABLE_LOG_LEVELS`       | Sets log levels as string instead of ints eg `info` instead of `30`, setting this to any value will switch                        | `nil`                                 |
 | `env.METRICS_PORT`                        | Specify the port for the prometheus metrics server                                                                                | `3001`                                |
 | `env.ROLE_PERMITTED_ANNOTATION`           | Specify the annotation key where to lookup the role arn permission boundaries                                                     | `iam.amazonaws.com/permitted`         |

config/environment.js

@@ -31,6 +31,10 @@ const pollerIntervalMilliseconds = process.env.POLLER_INTERVAL_MILLISECONDS
   ? Number(process.env.POLLER_INTERVAL_MILLISECONDS) : 10000
 
 const logLevel = process.env.LOG_LEVEL || 'info'
+const os = require('os')
+const logBasePidKey = process.env.LOG_BASE_PID_KEY || 'pid'
+const logBaseHostnameKey = process.env.LOG_BASE_HOSTNAME_KEY || 'hostname'
+const logBase = { [logBasePidKey]: process.pid, [logBaseHostnameKey]: os.hostname() }
 const useHumanReadableLogLevels = 'USE_HUMAN_READABLE_LOG_LEVELS' in process.env
 const logMessageKey = process.env.LOG_MESSAGE_KEY || 'msg'
 
@@ -70,6 +74,7 @@ module.exports = {
   enforceNamespaceAnnotation,
   pollingDisabled,
   logLevel,
+  logBase,
   useHumanReadableLogLevels,
   logMessageKey,
   watchTimeout,

config/index.js

@@ -40,6 +40,7 @@ const logger = pino({
   redact: ['err.options.headers', 'err.options.json.jwt'],
   messageKey: envConfig.logMessageKey || 'msg',
   level: envConfig.logLevel,
+  base: envConfig.logBase,
   formatters: {
     level (label, number) {
       return { level: envConfig.useHumanReadableLogLevels ? label : number }