<!-- Copyright JS Foundation and other contributors, http://js.foundation Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. --> <script type="text/html" data-help-name="delay"> <p>Delays each message passing through the node or limits the rate at which they can pass.</p> <h3>Inputs</h3> <dl class="message-properties"> <dt class="optional">delay <span class="property-type">number</span></dt> <dd>Sets the delay, in milliseconds, to be applied to the message. This option only applies if the node is configured to allow the message to override the configured default delay interval.</dd> <dt class="optional">reset</dt> <dd>If the received message has this property set to any value, all outstanding messages held by the node are cleared without being sent.</dd> <dt class="optional">flush</dt> <dd>If the received message has this property set to any value, all outstanding messages held by the node are sent immediately.</dd> </dl> <h3>Details</h3> <p>When configured to delay messages, the delay interval can be a fixed value, a random value within a range or dynamically set for each message. Each message is delayed independently of any other message, based on the time of its arrival. </p> <p>When configured to rate limit messages, their delivery is spread across the configured time period. The status shows the number of messages currently in the queue. It can optionally discard intermediate messages as they arrive.</p> </p> <p>The rate limiting can be applied to all messages, or group them according to their <code>msg.topic</code> value. When grouping, intermerdiate messages are automatically dropped. At each time interval, the node can either release the most recent message for all topics, or release the most recent message for the next topic. </p> </script>