new Updater()
An updater provides methods to update a topic on the server with a new supplied value, like Session.topics#update, but within the context of an exclusive TopicUpdateHandler registration. If the update is successful it will call the result's success callback, and any sessions subscribed to the same topic will be notified of a topic update.
An updater may only update topics at or below the registration path of the TopicUpdateHandler from which it was produced.
The result will fail if the update was not successful. It is necessary for the topic to
exist, and that the value type must be valid for the topic, for example a topic added with Metadata.Integer
cannot accept a string value. Updates will also fail if the TopicUpdateHandler this updater was created from
is in a standby
or closed
state.
- Deprecated:
-
- since 6.2
This class is deprecated. It is only used in conjunction with Session.topics#registerUpdateSource. Use topicUpdate.createUpdateStream instead. This method will be removed in a future release.
- since 6.2
Example
updater.update('foo/bar', 123).then(function() { // Update successful }, function(err) { // Update failed });
Methods
-
update(topicPath, value)
-
Update a topic
Prefer #updateValue when updating a
Double
orInt64
topic. This method can infer the wrong data type when updating aDouble
topic with a value that does not have a fractional component.Parameters:
Name Type Description topicPath
String The topic to update
value
Object The value to update the topic with
Returns:
- The Result.<undefined> of the update call
- Type
- Result.<undefined>
-
updateValue(topicPath, value, datatype)
-
Update a topic with a specified data type.
Parameters:
Name Type Description topicPath
String The topic to update
value
Object The value to update the topic with
datatype
Datatype The data type to be used for encoding the value
Returns:
- The Result.<undefined> of the update call
- Type
- Result.<undefined>