markap14 commented on a change in pull request #3725: NIFI-6558 Added Parameters to User Guide and Sys Admin Guide URL: https://github.com/apache/nifi/pull/3725#discussion_r323897283
########## File path: nifi-docs/src/main/asciidoc/user-guide.adoc ########## @@ -711,15 +711,187 @@ whatever comments are appropriate for this component. Use of the Comments tab is image::comments-tab.png["Comments Tab"] -=== Additional Help +==== Additional Help You can access additional documentation about each Processor's usage by right-clicking on the Processor and selecting 'Usage' from the context menu. Alternatively, select Help from the Global Menu in the top-right 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. +[[Parameters]] +=== Parameters +The values of properties in the flow, including sensitive properties, can be parameterized using Parameters. Parameters are created and configured within the NiFi UI. Any property can be configured to reference a Parameter with the following conditions: + + - A sensitive property can only reference a Sensitive Parameter + - A non-sensitive property can only reference a non-Sensitive Parameter + - Properties that reference Controller Services can not use Parameters + +NOTE: NiFi automatically picks up new or modified parameters. + +[[parameter-contexts]] +==== Parameter Contexts +Parameters are created within Parameter Contexts. Parameter Contexts are globally defined/accessible to the NiFi instance. Access policies can be applied to Parameter Contexts to determine which users can create them. Once created, policies to read and write to a specific Parameter Context can also be applied (see <<accessing-parameters>> for more information). + +===== Creating a Parameter Context +To create a Parameter Context, select Parameter Contexts from the Global Menu: + +image:parameter-contexts-selection.png["Global Menu - Parameter Contexts"] + +In the Parameter Contexts window, click the `+` button in the upper-right corner and the Add Parameter Context window opens. The window has two tabs: Settings and Parameters. + +image:parameter-contexts-settings.png["Parameter Contexts - Settings"] + +On the "Settings" tab, add a name for the Parameter Context and a description if desired. Select "Apply" to save the Parameter Context or select the "Parameters" tab to add parameters to the context. + +==== Adding a Parameter to a Parameter Context +Parameters can be added during Parameter Context creation or added to existing Parameter Contexts. + +During Parameter Context creation, select the "Parameters" tab. Click the `+` button to open the Add Parameter window. + +image:add-parameter-during-parameter-context-creation.png[Add Parameter] + +To add parameters to an existing Parameter Context, open the Parameter Context window and click the Edit button (image:iconEdit.png["Edit"]) in the row of the desired Parameter Context. + +image:edit-parameter-context.png[Edit Parameter Context] + +On the "Parameters" tab, click the `+` button to open the Add Parameter window. + +The Add Parameter window has the following settings: + +- *Name* - A name that is used to denote the Parameter. Only alpha-numeric characters (a-z, A-Z, 0-9), hyphens ( - ), underscores ( _ ), periods ( . ), and spaces are allowed. + +- *Value* - The value that will be used when the Parameter is referenced. + +- *Set empty string* - Check to explicity set the value of the Parameter to an empty string. Unchecked by default. + +- *Sensitive Value* - Set to "Yes" if the Parameter's Value should be considered sensitive. If sensitive, the value of the Parameter will not be shown in the UI once applied. The default setting is "No". + +- *Description* - A description that explains what the Parameter is, how it is to be used, etc. This field is optional. + +Once these settings are configured, select "Apply". Add additional Parameters or edit any existing Parameters. + +image:update-parameter-context.png[Update Parameter Context] + +To complete the process, select "Apply" from the Parameter Context window. The following operations are performed to validate all components that reference the added or modified parameters: Stopping/Restarting affected Processors, Disabling/Re-enabling affected Controller Services, Updating Parameter Context. + +image:parameters-validate-affected-components.png[Validate Affected Components] + +The Referencing Components section lists any components referencing the parameters in the parameter context organized by process group. + +[[assigning_parameter_context_to_PG]] +==== Assigning a Parameter Context to a Process Group +For a component to reference a Parameter, its Process Group must first be assigned to a Parameter Context. Once assigned, processors and controller services within that Process Group may only reference Parameters within that Parameter Context. + +NOTE: A user can only set the Parameter Context of a Process Group to one of the Parameter Contexts that the user has the view policy for. Additionally, in order to set the Parameter Context, the user must have the modify policy for the Process Group. See <<accessing-parameters>> for more information. + +To assign a Parameter Context to a Process group, click Configure, either from the Operate Palette or from the Process Group context menu. + +image:process-group-configuration-parameters.png[Configure Process Group Parameter Context] + +In the Flow Configuration window, select the "General" tab. From the Process Group Parameter Context drop-down menu, select an existing Parameter Context or create a new one. + +image:process-group-parameter-context-menu.png[Process Group Parameter Context Menu] + +Select "Apply" to save the configuration changes. The Process Group context menu now includes a "Parameters" option which allows quick access to the Update Parameter Context window for the assigned Parameter Context. + +image:context-menu-parameters-option.png[Context Menu Parameters Option] + +If the Parameter Context for a Process Group is changed, all components that reference any Parameters in that Process Group will be stopped, validated, and restarted (assuming the changes are valid). Review comment: I would reword "assuming the changes are valid" to something more along the lines of "assuming that the component is valid". It's not that the changes themselves are invalid but rather than the component may no longer be valid. It may also be worth pointing out that it will only be restarted if it was running - a stopped component won't be started. Perhaps "(assuming that the component was previously running and is still valid)" ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: [email protected] With regards, Apache Git Services
