THIS IS A TEST INSTANCE. ALL YOUR CHANGES WILL BE LOST!!!!
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Status
Current state: Under DiscussionAccepted
Discussion thread: here
JIRA: KAFKA-4743
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Released: 0.11.0.0
Please keep the discussion on the mailing list rather than commenting on the wiki (wiki discussions get unwieldy fast).
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Proposed Changes
We are considering to add the options in ConsumerGroupCommand to reset offsets.
There will be 3 execution options available:
- Plan: Print out the result of the operation (i.e. show a list of topic, partition, current offset, new offset to reset if the operation is executed). This will be the default option.
- Execute: Users will have to explicitly ask to execute the reset operation depending on the scenario and the scope specified.
- Export: Export plan to a CSV file to execute it later.
All these options are considered to be executed affecting only one Consumer Group.
The following scenarios will be supported:
| ID | Scenario | Description |
|---|---|---|
| 1. | Reset to Datetime | When we want to reset offsets to an specific point in time. (e.g. to 1/1/2017 at 00:00 to reprocess all records from these year) |
| 2. | Reset from Duration | When we want to go back some period ago (e.g. P7D to reprocess all records from one week ago) |
| 3. | Reset to Earliest | When we want to reprocess all the records available by partition. |
| 4. | Reset to Latest | When a Consumer Groups has an offset lag and we don't want to process missing records, only move to the latest. |
| 5. | Reset to Current Time | When we want to only print out and/or backup the current offset by partition. |
| 6. | Reset to Offset | When we want to move to an specific offset. |
| 7. | Shift Offset by 'n' | When we want to move forward or backward from the current position. 'n' can be a positive or negative value that will be add it to the current offset to move to a new position. |
| 8. | Reset from file | When we have a file with the required offsets by topic/partition to reset to. |
And the following scopes:
- All Topics consumed by Consumer Group: This scope will consider all the topics that has been consumed by a Consumer Group.
- Specific List of Topics: This scope will consider all the topics defined by user.
- One Topic, All Partitions: This scope will consider only one topic and all partitions.
- One Topic, Specific Partition: This scope will consider only one topic and partition specified by user.
You can check the concept-proof implementation of this feature on this branchpull request.
Public Interfaces
Consumer Group Reset Offset options
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This option should be executed independently from other Consumer Group options (list, describe, delete, etc.)etc.) and it will only support new consumers.
Required Arguments
| ID | Argument | Type | Descriptio |
|---|---|---|---|
| 1. | --group | Required | Consumer Group ID. |
| 2. | --bootstrap-server | Required | Server to connect to. |
Scenarios
At least one of the scenarios should be defined to proceed with the execution
| ID | Scenario | Arguments | Considerations | Example | |||
|---|---|---|---|---|---|---|---|
| 1. | Reset to Datetime | 1. | Reset to Timestamp | --to-datetime YYYY-MM-DDTHH:mm:SS.sss±hh:mm --to-datetime YYYY-MM-DDTHH:mm:SS.sssZ | --to-datetime YYYY-MM-DDTHH:mm:SS.sss | Datetime must be specified in ISO8601 format. This option will translate the datetime to Epoch milliseconds, find the offsets by timestamp, and reset to those offsets. It will use the datetime specified plus the default timezone where the client is running (i.e. ZoneId#systemDefault)If the Timezone is not specified, it will use UTC. | Reset to first offset since 01 January 2017, 00:00:00 hrs --reset-offsets –group test.group --topic foo --to-datetime 2017-01-01T00:00:0000Z |
| 2. | Reset by Duration | --by-duration PnDTnHnMnSS | Duration must be specified in ISO8601 format. This option will subtract the duration to the current timestamp in the server, and find the offsets using that subtracted timestamp, and reset to those offsets. The duration specified won't consider daylight saving effects. | Reset to first offset since one week ago (from current timestamp): --reset-offsets --group test.group --topic foo --by-duration P7D | |||
| 3. | Reset to Earliest | --to-earliest | This option will reset offsets to the earliest using Kafka Consumer's `#seekToBeginning` | Reset to earliest offset available: --reset-offsets --group test.group --topic foo --to-earliest | |||
| 4. | Reset to Latest | --to-latest | This option will reset offsets to the earliest using Kafka Consumer's `#seekToEnd` | Reset to latest offset available: --reset-offsets --group test.group --topic foo --to-latest | |||
| 5. | Reset to Current Position | (no scenario arguments) | This option won't reset the offset. It will be used to print and export current offset. | Reset to current position: --reset-offsets --group test.group --topic foo | |||
| 6. | Reset to Offset | --to-offset | This option will reset offsets to an specific value. | Reset to offset 1 in all partitions: --reset-offsets --group test.group --topic foo --to-offset 1 | |||
| 7. | Shift Offset by 'n' | --shift-by n | This option will add the `n` value to the current offset, and reset to the result. `n` can be a positive or negative value, so offset will be move backward if it is negative, and forward if it is positive. If current offset + n is higher than the latest offset, new offset will be set to latest. If current offset + n is lower than the earliest offset, new offset will be set to earliest. | Reset to current offset plus 5 positions: --reset-offsets --group test.group –topic foo --shift-by 5 | |||
| 8 | Reset from File | --from-file PATH_TO_FILE | This option will take a Reset Plan CSV file with the offsets to reset by topics/partitions. It does not require scope, because topics and partitions are defined in the file. | Reset using a file with reset plan: --reset-offsets --group test.group --from-file reset-plan.csv |
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| ID | Option | Arguments | Description | Examples |
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| 1. | Plan | (no execution arguments) | This execution option will only print out the result of the scenario by scope. The output will look like this: TOPIC PARTITION CURRENT-OFFSET CURRENT-LAG NEW-OFFSET NEW-LAG LOG-END-OFFSET CONSUMER-ID HOST CLIENT-ID | Prints result of resetting all topics and partitions to earliest: --reset-offsets --group test.group --all-topics –to-earliest |
| 2. | Execute | --execute | This execution option will run the reset offset process based on scenario and scope. | Prints and execute resetting all topics and partitions to earliest: --reset-offsets --group test.group --all-topics –to-earliest --execute |
| 3. | Export | --export | This execution option will print out the reset plan in CSV format, that later could be used in the scenario 8. (i.e. as backup) | Prints plan for resetting all topics and partitions to earliest in CSV format: --reset-offsets --group test.group --all-topics –to-earliest --export Execute and Prints plan for resetting all topics and partitions to earliest in CSV format: --reset-offsets --group test.group --all-topics –to-earliest --export --execute |
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(5) It will be executed only if it is asked explictly. This will consist in create a Consumer using the same `group.id` and use:
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consumer.assign(List(topicPartition).asJava)
consumer.seek(topicPartition, offset)
consumer.commitSync() |
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Nevertheless, it is possible to achieve the same result since release 0.10.0 using timestamp metadata by record, doing a linear search starting from latest. However, we are not considering to support this option because it will be an expensive/slow option.
All the other options will be available for releases from 0.10.0.0 given that KIP-97 is implemented.
This KIP will not support old consumers that store offsets in Zookeeper.
Test Plan
- A unit test to validate that --reset-offset is executed independently from other Consumer Group options (list, delete, describe, etc.)
- A unit test to validate that only one scenario is specified
- A unit test to validate that only one scope is specified
- A unit test to validate that only one execution option is specified
- A unit test by combination of scenario, scope and execution option.
- A unit test to validate that when calculated offset by partition is older that the earliest offset, tool resets offset to earliest (e.g. when we specified --reset-to 0, when earliest offset is 10)
- A unit test to validate that when calculated offset by partition is bigger that the latest offset, tool resets offset to latest (e.g. when we specified --reset-to 0, when earliest offset is 10)
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