Repository: nifi Updated Branches: refs/heads/master 7bc7b7f68 -> 74661e662
NIFI-2556 This closes #868. Updated User Guide with informaiton about custom properties Project: http://git-wip-us.apache.org/repos/asf/nifi/repo Commit: http://git-wip-us.apache.org/repos/asf/nifi/commit/74661e66 Tree: http://git-wip-us.apache.org/repos/asf/nifi/tree/74661e66 Diff: http://git-wip-us.apache.org/repos/asf/nifi/diff/74661e66 Branch: refs/heads/master Commit: 74661e662327415493c87cd6bbd39311ab1c7c9d Parents: 7bc7b7f Author: Sarah Olson <sol...@hortonworks.com> Authored: Mon Aug 15 14:31:58 2016 -0700 Committer: joewitt <joew...@apache.org> Committed: Wed Aug 17 13:24:49 2016 -0700 ---------------------------------------------------------------------- nifi-docs/src/main/asciidoc/user-guide.adoc | 30 ++++++++++++++++++++++++ 1 file changed, 30 insertions(+) ---------------------------------------------------------------------- http://git-wip-us.apache.org/repos/asf/nifi/blob/74661e66/nifi-docs/src/main/asciidoc/user-guide.adoc ---------------------------------------------------------------------- diff --git a/nifi-docs/src/main/asciidoc/user-guide.adoc b/nifi-docs/src/main/asciidoc/user-guide.adoc index 2ac03bb..1aa8e6f 100644 --- a/nifi-docs/src/main/asciidoc/user-guide.adoc +++ b/nifi-docs/src/main/asciidoc/user-guide.adoc @@ -590,7 +590,37 @@ on the Processor and selecting `Usage' from the context menu. Alternatively, sel corner of the UI to display a Help page with all of the documentation, including usage documentation for all the Processors that are available. Click on the desired Processor to view usage documentation. +[[Using_Custom_Properties]] +=== Using Custom Properties with Expression Language +You can use NiFi Expression Language to reference FlowFile attributes, compare them to other values, +and manipulate their values when you are creating and configuring dataflows. +In addition to using FlowFile attributes, system properties, and environment properties within Express +Language, you can also define custom properties for Expression Language use. Defining custom properties +gives you more flexibility in handling and processing dataflows. You can also create custom properties +for connection, server, and service properties, for easier dataflow configuration. + +To create custom properties for use with Expression Language, identify one or more sets of key/value +pairs, and give them to your system administrator. + +NiFi properties have resolution precedence of which you should be aware when creating custom properties:⨠+ + +* Processor-specific attributes +* FlowFile properties⨠+* FlowFile attributes⨠+* From variable registry:⨠+** User defined properties (custom properties) +** System properties⨠+** Operating System environment variables + +When you are creating custom properties, ensure that each custom property contains a distinct property value, +so that it is not overridden by existing environment properties, system properties, or FlowFile attributes. +Once you have added the new custom properties, ensure that you have updated the nifi.variable.registry.properties +field in the nifi.properties file, with the custom properties location. + +For more information on Expression Language, see the link:expression-language-guide.html[Expression Lanuaguage Guide]. +For information on how to define custom properties, see the link:administration-guide.html[System Administratorâs Guide]. [[Controller_Services_and_Reporting_Tasks]] === Controller Services and Reporting Tasks
