Details

    • Type: New Feature
    • Status: Patch Available
    • Priority: Major
    • Resolution: Unresolved
    • Affects Version/s: None
    • Fix Version/s: None
    • Component/s: None
    • Labels:
      None

      Description

      For some flows, it is imperative that the flow files are processed in a certain order. The PriorityAttributePrioritizer can be used on a connection to ensure that flow files going through that connection are in priority order, but depending on error-handling, branching, and other flow designs, it is possible for flow files to get out-of-order.

      I propose an EnforceOrder processor, which would be single-threaded and have (at a minimum) the following properties:

      1) Order Attribute: This would be the name of a flow file attribute from which the current value will be retrieved.
      2) Initial Value: This property specifies an initial value for the order. The processor is stateful, however, so this property is only used when there is no entry in the state map for current value.

      The processor would store the Initial Value into the state map (if no state map entry exists), then for each incoming flow file, it checks the value in the Order Attribute against the current value. If the attribute value matches the current value, the flow file is transferred to the "success" relationship, and the current value is incremented in the state map. If the attribute value does not match the current value, the session will be rolled back.

      Using this processor, along with a PriorityAttributePrioritizer on the incoming connection, will allow for out-of-order flow files to have a sort of "barrier", thereby guaranteeing that flow files transferred to the "success" relationship are in the specified order.

        Issue Links

          Activity

          Hide
          ijokarumawak Koji Kawamura added a comment -

          Hi Matt Burgess,

          I'm interested in working on this. To understand the requirement properly, would you share some example NiFi flow that possibly violate desired ordering?

          Show
          ijokarumawak Koji Kawamura added a comment - Hi Matt Burgess , I'm interested in working on this. To understand the requirement properly, would you share some example NiFi flow that possibly violate desired ordering?
          Hide
          mattyb149 Matt Burgess added a comment -

          Certainly! Consider a set of incoming flow files that contain JSON objects, each with a field "status" with a value of "OK" or "ERROR". After extracting this code with EvaluateJsonPath, a RouteOnAttribute might follow, and there might be different processing for "OK" files vs "ERROR" files. Then if the two branches meet again by being connected to a funnel or a common processor, the original order of the flow files may not be preserved. This processor would use the Order Attribute property (and the flow would have to be configured with the correct Prioritizers as mentioned in the description) to ensure that the output of EnforceOrder retains the original order of the incoming flow files.

          Show
          mattyb149 Matt Burgess added a comment - Certainly! Consider a set of incoming flow files that contain JSON objects, each with a field "status" with a value of "OK" or "ERROR". After extracting this code with EvaluateJsonPath, a RouteOnAttribute might follow, and there might be different processing for "OK" files vs "ERROR" files. Then if the two branches meet again by being connected to a funnel or a common processor, the original order of the flow files may not be preserved. This processor would use the Order Attribute property (and the flow would have to be configured with the correct Prioritizers as mentioned in the description) to ensure that the output of EnforceOrder retains the original order of the incoming flow files.
          Hide
          ijokarumawak Koji Kawamura added a comment -

          Thanks Matt for explaining detailed use-case. (I thought I wrote a reply last week but the comment wasn't saved properly..)

          I'm going to implement the processor, and add following capabilities as well:

          • To not update state storage too often, batch up input flow files max to 'Max Batch Count' and process those at once
          • Group incoming flow files by 'Group Identifier', and handle multiple groups
          • Add 'wait' queue to route flow files those didn't match with current order number, so that those leave from the incoming queue and make room for other flow files can be enqueued. Penalize those, too.
          • Track how long a flow file has been waiting. If it exceeds configured 'Timeout', routes it to 'timeout' relationship. Update the order number with the maximum + 1 of timeout flow files, so that if the skipped flow file arrives later, processor can detect it
          • If incoming file has an order number younger than the current, then route it to 'skipped' relationship
          Show
          ijokarumawak Koji Kawamura added a comment - Thanks Matt for explaining detailed use-case. (I thought I wrote a reply last week but the comment wasn't saved properly..) I'm going to implement the processor, and add following capabilities as well: To not update state storage too often, batch up input flow files max to 'Max Batch Count' and process those at once Group incoming flow files by 'Group Identifier', and handle multiple groups Add 'wait' queue to route flow files those didn't match with current order number, so that those leave from the incoming queue and make room for other flow files can be enqueued. Penalize those, too. Track how long a flow file has been waiting. If it exceeds configured 'Timeout', routes it to 'timeout' relationship. Update the order number with the maximum + 1 of timeout flow files, so that if the skipped flow file arrives later, processor can detect it If incoming file has an order number younger than the current, then route it to 'skipped' relationship
          Hide
          githubbot ASF GitHub Bot added a comment -

          GitHub user ijokarumawak opened a pull request:

          https://github.com/apache/nifi/pull/1496

          NIFI-3414: Added EnforceOrder processor

          Use it with FirstInFirstOutPrioritizer, it can enforce original ordering
          of 'out-of-order' FlowFiles.

          nifi-mock is modified to support FlowFile assertion using Prioritizer.

          Thank you for submitting a contribution to Apache NiFi.

          In order to streamline the review of the contribution we ask you
          to ensure the following steps have been taken:

              1. For all changes:
          • [x] Is there a JIRA ticket associated with this PR? Is it referenced
            in the commit message?
          • [x] Does your PR title start with NIFI-XXXX where XXXX is the JIRA number you are trying to resolve? Pay particular attention to the hyphen "-" character.
          • [x] Has your PR been rebased against the latest commit within the target branch (typically master)?
          • [x] Is your initial contribution a single, squashed commit?
              1. For code changes:
          • [x] Have you ensured that the full suite of tests is executed via mvn -Pcontrib-check clean install at the root nifi folder?
          • [x] Have you written or updated unit tests to verify your changes?
          • [ ] If adding new dependencies to the code, are these dependencies licensed in a way that is compatible for inclusion under [ASF 2.0](http://www.apache.org/legal/resolved.html#category-a)?
          • [ ] If applicable, have you updated the LICENSE file, including the main LICENSE file under nifi-assembly?
          • [ ] If applicable, have you updated the NOTICE file, including the main NOTICE file found under nifi-assembly?
          • [ ] If adding new Properties, have you added .displayName in addition to .name (programmatic access) for each of the new properties?
              1. For documentation related changes:
          • [x] Have you ensured that format looks appropriate for the output in which it is rendered?
              1. Note:
                Please ensure that once the PR is submitted, you check travis-ci for build issues and submit an update to your PR as soon as possible.

          You can merge this pull request into a Git repository by running:

          $ git pull https://github.com/ijokarumawak/nifi nifi-3414

          Alternatively you can review and apply these changes as the patch at:

          https://github.com/apache/nifi/pull/1496.patch

          To close this pull request, make a commit to your master/trunk branch
          with (at least) the following in the commit message:

          This closes #1496


          commit a60fc5d88e1a1ab3190052f19e228908e996c818
          Author: Koji Kawamura <ijokarumawak@apache.org>
          Date: 2017-02-07T15:13:23Z

          NIFI-3414: Added EnforceOrder processor

          Use it with FirstInFirstOutPrioritizer, it can enforce original ordering
          of 'out-of-order' FlowFiles.

          nifi-mock is modified to support FlowFile assertion using Prioritizer.


          Show
          githubbot ASF GitHub Bot added a comment - GitHub user ijokarumawak opened a pull request: https://github.com/apache/nifi/pull/1496 NIFI-3414 : Added EnforceOrder processor Use it with FirstInFirstOutPrioritizer, it can enforce original ordering of 'out-of-order' FlowFiles. nifi-mock is modified to support FlowFile assertion using Prioritizer. Thank you for submitting a contribution to Apache NiFi. In order to streamline the review of the contribution we ask you to ensure the following steps have been taken: For all changes: [x] Is there a JIRA ticket associated with this PR? Is it referenced in the commit message? [x] Does your PR title start with NIFI-XXXX where XXXX is the JIRA number you are trying to resolve? Pay particular attention to the hyphen "-" character. [x] Has your PR been rebased against the latest commit within the target branch (typically master)? [x] Is your initial contribution a single, squashed commit? For code changes: [x] Have you ensured that the full suite of tests is executed via mvn -Pcontrib-check clean install at the root nifi folder? [x] Have you written or updated unit tests to verify your changes? [ ] If adding new dependencies to the code, are these dependencies licensed in a way that is compatible for inclusion under [ASF 2.0] ( http://www.apache.org/legal/resolved.html#category-a)? [ ] If applicable, have you updated the LICENSE file, including the main LICENSE file under nifi-assembly? [ ] If applicable, have you updated the NOTICE file, including the main NOTICE file found under nifi-assembly? [ ] If adding new Properties, have you added .displayName in addition to .name (programmatic access) for each of the new properties? For documentation related changes: [x] Have you ensured that format looks appropriate for the output in which it is rendered? Note: Please ensure that once the PR is submitted, you check travis-ci for build issues and submit an update to your PR as soon as possible. You can merge this pull request into a Git repository by running: $ git pull https://github.com/ijokarumawak/nifi nifi-3414 Alternatively you can review and apply these changes as the patch at: https://github.com/apache/nifi/pull/1496.patch To close this pull request, make a commit to your master/trunk branch with (at least) the following in the commit message: This closes #1496 commit a60fc5d88e1a1ab3190052f19e228908e996c818 Author: Koji Kawamura <ijokarumawak@apache.org> Date: 2017-02-07T15:13:23Z NIFI-3414 : Added EnforceOrder processor Use it with FirstInFirstOutPrioritizer, it can enforce original ordering of 'out-of-order' FlowFiles. nifi-mock is modified to support FlowFile assertion using Prioritizer.
          Hide
          githubbot ASF GitHub Bot added a comment -

          Github user ijokarumawak commented on the issue:

          https://github.com/apache/nifi/pull/1496

          I've written a Gist with a flow template to describe how this is intended to work, hope this helps for reviewing PR. Thanks!
          https://gist.github.com/ijokarumawak/88fc30a2300845b3c27a79113fc72d41

          Show
          githubbot ASF GitHub Bot added a comment - Github user ijokarumawak commented on the issue: https://github.com/apache/nifi/pull/1496 I've written a Gist with a flow template to describe how this is intended to work, hope this helps for reviewing PR. Thanks! https://gist.github.com/ijokarumawak/88fc30a2300845b3c27a79113fc72d41
          Hide
          githubbot ASF GitHub Bot added a comment -

          Github user pvillard31 commented on the issue:

          https://github.com/apache/nifi/pull/1496

          Hey @ijokarumawak, I did few tests with your processor following your Gist explanations and using your template. It worked as expected. I'll try to test other scenarios. In the meantime, could you use both ``.name()`` and ``.displayName()`` in the processor properties?

          Show
          githubbot ASF GitHub Bot added a comment - Github user pvillard31 commented on the issue: https://github.com/apache/nifi/pull/1496 Hey @ijokarumawak, I did few tests with your processor following your Gist explanations and using your template. It worked as expected. I'll try to test other scenarios. In the meantime, could you use both ``.name()`` and ``.displayName()`` in the processor properties?
          Hide
          githubbot ASF GitHub Bot added a comment -

          Github user ijokarumawak commented on the issue:

          https://github.com/apache/nifi/pull/1496

          Hey @pvillard31 thanks for trying out this PR. I've update it to use both `.name()` and `.displayName`. Please let me know if you find anything suspicious during your test.

          Show
          githubbot ASF GitHub Bot added a comment - Github user ijokarumawak commented on the issue: https://github.com/apache/nifi/pull/1496 Hey @pvillard31 thanks for trying out this PR. I've update it to use both `.name()` and `.displayName`. Please let me know if you find anything suspicious during your test.

            People

            • Assignee:
              ijokarumawak Koji Kawamura
              Reporter:
              mattyb149 Matt Burgess
            • Votes:
              0 Vote for this issue
              Watchers:
              3 Start watching this issue

              Dates

              • Created:
                Updated:

                Development