feat: remember last poll thru poller restarts

external-secrets · Jul 23, 2019 · f6399c5 · f6399c5
1 parent 067b6a9
commit f6399c5
Showing 1 changed file with 32 additions and 6 deletions.
diff --git a/lib/poller.js b/lib/poller.js
@@ -1,5 +1,7 @@
 'use strict'
 
+const LAST_POLL = 'externalsecret.kubernetes-client.io/last-poll'
+
 /**
  * Kubernetes secret descriptor.
  * @typedef {Object} SecretDescriptor
@@ -58,7 +60,10 @@ class Poller {
         name: secretDescriptor.name,
         ownerReferences: [
           this._ownerReference
-        ]
+        ],
+        annotations: {
+          [LAST_POLL]: `${Date.now()}`
+        }
       },
       type: 'Opaque',
       data
@@ -71,12 +76,15 @@ class Poller {
    */
   async _poll () {
     this._logger.info('running poll')
+
     try {
       await this._upsertKubernetesSecret()
     } catch (err) {
       this._logger.error('failure while polling the secrets')
       this._logger.error(err)
     }
+
+    this._setNextPoll()
   }
 
   /**
@@ -100,14 +108,22 @@ class Poller {
 
   /**
    * Checks if secret exists, if not trigger a poll
+   * If secret already exists check when it was last polled and set timeout for next poll
    */
   async _checkForSecret () {
     const secretDescriptor = this._secretDescriptor
     const secretName = secretDescriptor.name
     const kubeNamespace = this._kubeClient.api.v1.namespaces(this._namespace)
 
     try {
-      await kubeNamespace.secrets(secretName).get()
+      const {
+        body: { metadata: { annotations = {} } = {} } = {}
+      } = await kubeNamespace.secrets(secretName).get()
+
+      const lastPoll = parseInt(annotations[LAST_POLL] || '0', 10)
+      const nextPollIn = Math.max(lastPoll - (Date.now() - this._intervalMilliseconds), 0)
+
+      this._setNextPoll(nextPollIn)
     } catch (err) {
       if (err.statusCode === 404) {
         this._logger.info('Secret does not exist, polling right away')
@@ -116,6 +132,16 @@ class Poller {
     }
   }
 
+  _setNextPoll (nextPollIn = this._intervalMilliseconds) {
+    if (this._interval) {
+      clearTimeout(this._interval)
+      this._interval = null
+    }
+
+    this._interval = setTimeout(this._poll.bind(this), nextPollIn)
+    this._logger.debug('Next poll for %s in %s in %s', this._secretDescriptor.name, this._namespace, nextPollIn)
+  }
+
   /**
    * Start poller.
    * @param {boolean} forcePoll - Trigger poll right away
@@ -124,14 +150,14 @@ class Poller {
   start ({ forcePoll = false } = {}) {
     if (this._interval) return this
 
+    this._logger.debug('starting poller')
+
     if (forcePoll) {
       this._poll()
     } else {
       this._checkForSecret()
     }
 
-    this._logger.info('starting poller')
-    this._interval = setInterval(this._poll.bind(this), this._intervalMilliseconds)
     return this
   }
 
@@ -141,8 +167,8 @@ class Poller {
    */
   stop () {
     if (!this._interval) return this
-    this._logger.info('stopping poller')
-    clearInterval(this._interval)
+    this._logger.debug('stopping poller')
+    clearTimeout(this._interval)
     this._interval = null
     return this
   }