Conditions

When a watch is triggered, its condition determines whether or not to execute the watch actions. Watcher supports the following condition types:

  • always: set the watch condition to true so the watch actions are always executed.
  • never: set the watch condition to false so the watch actions are never executed.
  • compare: perform simple comparisons against values in the watch payload to determine whether or not to execute the watch actions.
  • array_compare: compare an array of values in the watch payload to a given value to determine whether or not to execute the watch actions.
  • script: use a script to determine wehther or not to execute the watch actions.

If you omit the condition definition from a watch, the condition defaults to always.

When a condition is evaluated, it has full access to the watch execution context, including the watch payload (ctx.payload.*). The script, compare and array_compare conditions can use the payload data to determine whether or not the necessary conditions are met.