<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"></meta><title>PublishKafka_1_0</title><link rel="stylesheet" href="../../../../../css/component-usage.css" type="text/css"></link></head><script type="text/javascript">window.onload = function(){if(self==top) { document.getElementById('nameHeader').style.display = "inherit"; } }</script><body><h1 id="nameHeader" style="display: none;">PublishKafka_1_0</h1><h2>Description: </h2><p>Sends the contents of a FlowFile as a message to Apache Kafka using the Kafka 1.0 Producer API.The messages to send may be individual FlowFiles or may be delimited, using a user-specified delimiter, such as a new-line. The complementary NiFi processor for fetching messages is ConsumeKafka_1_0.</p><p><a href="additionalDetails.html">Additional Details...</a></p><h3>Tags: </h3><p>Apache, Kafka, Put, Send, Message, PubSub, 1.0</p><h3>Properties: </h3><p>In the list below, the names of required properties appear in <strong>bold</strong>. Any other properties (not in bold) are considered optional. The table also indicates any default values, and whether a property supports the <a href="../../../../../html/expression-language-guide.html">NiFi Expression Language</a>.</p><table id="properties"><tr><th>Display Name</th><th>API Name</th><th>Default Value</th><th>Allowable Values</th><th>Description</th></tr><tr><td id="name"><strong>Kafka Brokers</strong></td><td>bootstrap.servers</td><td id="default-value">localhost:9092</td><td id="allowable-values"></td><td id="description">Comma-separated list of Kafka Brokers in the format host:port<br/><strong>Supports Expression Language: true (will be evaluated using variable registry only)</strong></td></tr><tr><td id="name"><strong>Security Protocol</strong></td><td>security.protocol</td><td id="default-value">PLAINTEXT</td><td id="allowable-values"><ul><li>PLAINTEXT</li><li>SSL</li><li>SASL_PLAINTEXT</li><li>SASL_SSL</li></ul></td><td id="description">Security protocol used to communicate with brokers. Corresponds to Kafka Client security.protocol property</td></tr><tr><td id="name">Kerberos Service Name</td><td>sasl.kerberos.service.name</td><td></td><td id="allowable-values"></td><td id="description">The service name that matches the primary name of the Kafka server configured in the broker JAAS configuration<br/><strong>Supports Expression Language: true (will be evaluated using variable registry only)</strong></td></tr><tr><td id="name">Kerberos Principal</td><td>sasl.kerberos.principal</td><td></td><td id="allowable-values"></td><td id="description">Principal used for authentication with Kerberos<br/><strong>Supports Expression Language: true (will be evaluated using variable registry only)</strong></td></tr><tr><td id="name">Kerberos Keytab</td><td>sasl.kerberos.keytab</td><td></td><td id="allowable-values"></td><td id="description">Keytab credentials used for authentication with Kerberos<br/><br/><strong>This property requires exactly one file to be provided..</strong><br/><br/><strong>Supports Expression Language: true (will be evaluated using variable registry only)</strong></td></tr><tr><td id="name">SSL Context Service</td><td>ssl.context.service</td><td></td><td id="allowable-values"><strong>Controller Service API: </strong><br/>SSLContextService<br/><strong>Implementations: </strong><a href="../../../nifi-ssl-context-service-nar/1.19.1/org.apache.nifi.ssl.StandardRestrictedSSLContextService/index.html">StandardRestrictedSSLContextService</a><br/><a href="../../../nifi-ssl-context-service-nar/1.19.1/org.apache.nifi.ssl.StandardSSLContextService/index.html">StandardSSLContextService</a></td><td id="description">Service supporting SSL communication with Kafka brokers</td></tr><tr><td id="name"><strong>Topic Name</strong></td><td>topic</td><td></td><td id="allowable-values"></td><td id="description">The name of the Kafka Topic to publish to.<br/><strong>Supports Expression Language: true (will be evaluated using flow file attributes and variable registry)</strong></td></tr><tr><td id="name"><strong>Delivery Guarantee</strong></td><td>acks</td><td id="default-value">Best Effort</td><td id="allowable-values"><ul><li>Best Effort <img src="../../../../../html/images/iconInfo.png" alt="FlowFile will be routed to success after successfully sending the content to a Kafka node, without waiting for any acknowledgment from the node at all. This provides the best performance but may result in data loss." title="FlowFile will be routed to success after successfully sending the content to a Kafka node, without waiting for any acknowledgment from the node at all. This provides the best performance but may result in data loss."></img></li><li>Guarantee Single Node Delivery <img src="../../../../../html/images/iconInfo.png" alt="FlowFile will be routed to success if the message is received by a single Kafka node, whether or not it is replicated. This is faster than &lt;Guarantee Replicated Delivery&gt; but can result in data loss if a Kafka node crashes" title="FlowFile will be routed to success if the message is received by a single Kafka node, whether or not it is replicated. This is faster than &lt;Guarantee Replicated Delivery&gt; but can result in data loss if a Kafka node crashes"></img></li><li>Guarantee Replicated Delivery <img src="../../../../../html/images/iconInfo.png" alt="FlowFile will be routed to failure unless the message is replicated to the appropriate number of Kafka Nodes according to the Topic configuration" title="FlowFile will be routed to failure unless the message is replicated to the appropriate number of Kafka Nodes according to the Topic configuration"></img></li></ul></td><td id="description">Specifies the requirement for guaranteeing that a message is sent to Kafka. Corresponds to Kafka's 'acks' property.</td></tr><tr><td id="name"><strong>Use Transactions</strong></td><td>use-transactions</td><td id="default-value">true</td><td id="allowable-values"><ul><li>true</li><li>false</li></ul></td><td id="description">Specifies whether or not NiFi should provide Transactional guarantees when communicating with Kafka. If there is a problem sending data to Kafka, and this property is set to false, then the messages that have already been sent to Kafka will continue on and be delivered to consumers. If this is set to true, then the Kafka transaction will be rolled back so that those messages are not available to consumers. Setting this to true requires that the &lt;Delivery Guarantee&gt; property be set to "Guarantee Replicated Delivery."</td></tr><tr><td id="name">Transactional Id Prefix</td><td>transactional-id-prefix</td><td></td><td id="allowable-values"></td><td id="description">When Use Transaction is set to true, KafkaProducer config 'transactional.id' will be a generated UUID and will be prefixed with this string.<br/><strong>Supports Expression Language: true (will be evaluated using variable registry only)</strong></td></tr><tr><td id="name">Attributes to Send as Headers (Regex)</td><td>attribute-name-regex</td><td></td><td id="allowable-values"></td><td id="description">A Regular Expression that is matched against all FlowFile attribute names. Any attribute whose name matches the regex will be added to the Kafka messages as a Header. If not specified, no FlowFile attributes will be added as headers.</td></tr><tr><td id="name">Message Header Encoding</td><td>message-header-encoding</td><td id="default-value">UTF-8</td><td id="allowable-values"></td><td id="description">For any attribute that is added as a message header, as configured via the &lt;Attributes to Send as Headers&gt; property, this property indicates the Character Encoding to use for serializing the headers.</td></tr><tr><td id="name">Kafka Key</td><td>kafka-key</td><td></td><td id="allowable-values"></td><td id="description">The Key to use for the Message. If not specified, the flow file attribute 'kafka.key' is used as the message key, if it is present.Beware that setting Kafka key and demarcating at the same time may potentially lead to many Kafka messages with the same key.Normally this is not a problem as Kafka does not enforce or assume message and key uniqueness. Still, setting the demarcator and Kafka key at the same time poses a risk of data loss on Kafka. During a topic compaction on Kafka, messages will be deduplicated based on this key.<br/><strong>Supports Expression Language: true (will be evaluated using flow file attributes and variable registry)</strong></td></tr><tr><td id="name"><strong>Key Attribute Encoding</strong></td><td>key-attribute-encoding</td><td id="default-value">UTF-8 Encoded</td><td id="allowable-values"><ul><li>UTF-8 Encoded <img src="../../../../../html/images/iconInfo.png" alt="The key is interpreted as a UTF-8 Encoded string." title="The key is interpreted as a UTF-8 Encoded string."></img></li><li>Hex Encoded <img src="../../../../../html/images/iconInfo.png" alt="The key is interpreted as arbitrary binary data and is encoded using hexadecimal characters with uppercase letters" title="The key is interpreted as arbitrary binary data and is encoded using hexadecimal characters with uppercase letters"></img></li><li>Do Not Add Key as Attribute <img src="../../../../../html/images/iconInfo.png" alt="The key will not be added as an Attribute" title="The key will not be added as an Attribute"></img></li></ul></td><td id="description">FlowFiles that are emitted have an attribute named 'kafka.key'. This property dictates how the value of the attribute should be encoded.</td></tr><tr><td id="name">Message Demarcator</td><td>message-demarcator</td><td></td><td id="allowable-values"></td><td id="description">Specifies the string (interpreted as UTF-8) to use for demarcating multiple messages within a single FlowFile. If not specified, the entire content of the FlowFile will be used as a single message. If specified, the contents of the FlowFile will be split on this delimiter and each section sent as a separate Kafka message. To enter special character such as 'new line' use CTRL+Enter or Shift+Enter, depending on your OS.<br/><strong>Supports Expression Language: true (will be evaluated using flow file attributes and variable registry)</strong></td></tr><tr><td id="name"><strong>Max Request Size</strong></td><td>max.request.size</td><td id="default-value">1 MB</td><td id="allowable-values"></td><td id="description">The maximum size of a request in bytes. Corresponds to Kafka's 'max.request.size' property and defaults to 1 MB (1048576).</td></tr><tr><td id="name"><strong>Acknowledgment Wait Time</strong></td><td>ack.wait.time</td><td id="default-value">5 secs</td><td id="allowable-values"></td><td id="description">After sending a message to Kafka, this indicates the amount of time that we are willing to wait for a response from Kafka. If Kafka does not acknowledge the message within this time period, the FlowFile will be routed to 'failure'.</td></tr><tr><td id="name"><strong>Max Metadata Wait Time</strong></td><td>max.block.ms</td><td id="default-value">5 sec</td><td id="allowable-values"></td><td id="description">The amount of time publisher will wait to obtain metadata or wait for the buffer to flush during the 'send' call before failing the entire 'send' call. Corresponds to Kafka's 'max.block.ms' property<br/><strong>Supports Expression Language: true (will be evaluated using variable registry only)</strong></td></tr><tr><td id="name">Partitioner class</td><td>partitioner.class</td><td id="default-value">DefaultPartitioner</td><td id="allowable-values"><ul><li>RoundRobinPartitioner <img src="../../../../../html/images/iconInfo.png" alt="Messages will be assigned partitions in a round-robin fashion, sending the first message to Partition 1, the next Partition to Partition 2, and so on, wrapping as necessary." title="Messages will be assigned partitions in a round-robin fashion, sending the first message to Partition 1, the next Partition to Partition 2, and so on, wrapping as necessary."></img></li><li>DefaultPartitioner <img src="../../../../../html/images/iconInfo.png" alt="Messages will be assigned to random partitions." title="Messages will be assigned to random partitions."></img></li><li>Expression Language Partitioner <img src="../../../../../html/images/iconInfo.png" alt="Interprets the &lt;Partition&gt; property as Expression Language that will be evaluated against each FlowFile. This Expression will be evaluated once against the FlowFile, so all Records in a given FlowFile will go to the same partition." title="Interprets the &lt;Partition&gt; property as Expression Language that will be evaluated against each FlowFile. This Expression will be evaluated once against the FlowFile, so all Records in a given FlowFile will go to the same partition."></img></li></ul></td><td id="description">Specifies which class to use to compute a partition id for a message. Corresponds to Kafka's 'partitioner.class' property.</td></tr><tr><td id="name">Partition</td><td>partition</td><td></td><td id="allowable-values"></td><td id="description">Specifies which Partition Records will go to.<br/><strong>Supports Expression Language: true (will be evaluated using flow file attributes and variable registry)</strong></td></tr><tr><td id="name"><strong>Compression Type</strong></td><td>compression.type</td><td id="default-value">none</td><td id="allowable-values"><ul><li>none</li><li>gzip</li><li>snappy</li><li>lz4</li></ul></td><td id="description">This parameter allows you to specify the compression codec for all data generated by this producer.</td></tr></table><h3>Dynamic Properties: </h3><p>Supports Sensitive Dynamic Properties: <strong>No</strong></p><p>Dynamic Properties allow the user to specify both the name and value of a property.<table id="dynamic-properties"><tr><th>Name</th><th>Value</th><th>Description</th></tr><tr><td id="name">The name of a Kafka configuration property.</td><td id="value">The value of a given Kafka configuration property.</td><td>These properties will be added on the Kafka configuration after loading any provided configuration properties. In the event a dynamic property represents a property that was already set, its value will be ignored and WARN message logged. For the list of available Kafka properties please refer to: http://kafka.apache.org/documentation.html#configuration. <br/><strong>Supports Expression Language: true (will be evaluated using variable registry only)</strong></td></tr></table></p><h3>Relationships: </h3><table id="relationships"><tr><th>Name</th><th>Description</th></tr><tr><td>success</td><td>FlowFiles for which all content was sent to Kafka.</td></tr><tr><td>failure</td><td>Any FlowFile that cannot be sent to Kafka will be routed to this Relationship</td></tr></table><h3>Reads Attributes: </h3>None specified.<h3>Writes Attributes: </h3><table id="writes-attributes"><tr><th>Name</th><th>Description</th></tr><tr><td>msg.count</td><td>The number of messages that were sent to Kafka for this FlowFile. This attribute is added only to FlowFiles that are routed to success. If the &lt;Message Demarcator&gt; Property is not set, this will always be 1, but if the Property is set, it may be greater than 1.</td></tr></table><h3>State management: </h3>This component does not store state.<h3>Restricted: </h3>This component is not restricted.<h3>Input requirement: </h3>This component requires an incoming relationship.<h3>System Resource Considerations:</h3>None specified.</body></html>