Watchers

Also known as listeners or triggers, these functions allow you to monitor collection activity; Each time a document is inserted, updated, replaced, or deleted, a call-back function is invoked.

Every document triggers its own event.

Note Each watcher runs in a separate worker thread.

(require '[com.timezynk.mongo.watch :as w])

(defn insert-fn [token time coll doc]
  ())

(w/on-insert :coll insert-fn)

Each of the trigger functions – on-insert, on-update, on-replace, on-delete – accepts a call-back function that must take three to five parameters:

• token The resume token, a unique string for the event.

• time Operation time, expressed as a java.util.Date object.

• collection The affected collection.

• document A map containing either:

  [on insert] The inserted document including the newly created :_id field.

  [on update] Either a delta with :_id, :update, :remove fields, or the full updated document.

  [on replace] The new document.

  [on delete] A document with either the :_id field or the full deleted document.

• optional document On update and replace, the old document.