[
https://issues.apache.org/jira/browse/NIP-2?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=18084228#comment-18084228
]
Florian Beck commented on NIP-2:
--------------------------------
It would be great.
"Run-Once", "replay event" or try to look after the output is kind of
frustrating in the development process.
I could image, that you could place a fixed input manually but also select from
the provenance data a ealier handled flowfiles. It would be great.
It would also wonderful for some specific services, to have such a preview
option. To start and stop a csv or json reader and configure stuff is sometimes
also unpleasant.
> Preview capability for processors
> ---------------------------------
>
> Key: NIP-2
> URL: https://issues.apache.org/jira/browse/NIP-2
> Project: NiFi Improvement Proposal
> Issue Type: New Feature
> Reporter: Matt Burgess
> Priority: Normal
>
> *Motivation*
> The ability to "send" a sample FlowFile through a processor in an existing
> flow, without being associated with the flow itself (provenance, I/O metrics,
> e.g.), rather by executing the configured processor using the provided input
> and returning the output could be highly beneficial for Flow Designers. It's
> somewhat analogous to the "Run Once" feature but aims to operate outside the
> actual flow framework so as not to potentially contaminate the various NiFi
> repositories keeping track of the flow of "real" data.
> *Scope*
> This would involve several changes and additions to the API and codebase, see
> the Description section for details.
> *Compatibility*
> This feature would be backwards-compatible as is it is new and can only be
> executed on a flow in a NiFi instance that supports this capability.
> *Description*
> This capability would provide a user to test a processor already in the flow
> during design before starting the flow with "real" data which can help debug
> flows while preventing data loss during development.
> Tasks:
> * REST API call(s) to POST data to endpoint(s) which respond with machine
> readable output (JSON, XML, e.g.)
> * An annotation on processors such as Previewable, perhaps the
> SideEffectFree annotation suffices but you cannot extend Java annotations so
> SideEffectFree processors may just be a good starting point
> * An established format for both the POST data and the output data (content
> and attributes, multiple FlowFiles, relationships, etc.)
> * UI changes to include:
> -- Context-sensitive (right-click) menu option to Preview
> -- Dialog to paste/upload/drag the input content
> -- Inject parameters (perhaps reuse the Verification capability here as
> prudent)
> -- Leverage the existing Content Viewer as prudent to show the output (both
> content and attributes in one place would be preferable, but code reuse in
> the UI helps with consistency and maintainability)
> * Documentation
> -- Add a section to the processors' documentation if they are Previewable, a
> common description could be provided to avoid the need for custom UIs
> -- Add a section to the User Guide to describe how to preview a Previewable
> processor and how to interpret the results
> -- Add a section as necessary to the Admin guide for allowing/disallowing
> Preview (see the Authorization section below)
> * Authorization
> -- Add a policy to allow/prevent previewing a processor (optional for this
> NIP as this is intended to be a "sandbox" operation)
> *Verification*
> As processors are augmented with the Previewable annotation, the pull
> requests should include unit tests and the overall documentation should
> describe how to use the Preview capability on a Previewable processor.
> *Alternatives*
> On development systems (or in development process groups), the GenerateXYZ
> processors can be used to inject data into the processor and the UI or the
> REST API can be used to inspect the output data from the connection. This can
> be quite cumbersome and requires a separate NiFi system or process group for
> testing flow development, then moving the tested flow into the target NiFi
> system.
--
This message was sent by Atlassian Jira
(v8.20.10#820010)
