I'm not sure I understand this use case well. What are you planning on
doing with the BQ dataset if it were processed first? Were you planning on
caching information in memory? Storing data in Beam state? Something else?
On Wed, Mar 1, 2023 at 10:43 AM Kenneth Knowles <k...@apache.org> wrote:
>
>
> On Tue, Feb 28, 2023 at 5:14 PM Sahil Modak <smo...@paloaltonetworks.com>
> wrote:
>
>> The number of keys/data in BQ would not be constant and grow with time.
>>
>> A rough estimate would be around 300k keys with an average size of 5kb
>> per key. Both the count of the keys and the size of the key would be
>> feature dependent (based on the upstream pipelines) and we won't have
>> control over this in the future.
>>
>> Using big query client would mean we would have to run individual queries
>> for each of these 300k keys from the BusinessLogic() dofn which operates in
>> a global window KV
>>
>> Also, the order of the data from BQ would not matter to us since the only
>> thing we are trying to solve here is regaining the state spec information
>> before starting to consume pub/sub.
>>
>
> I was referring to order in general, across your whole data set as an
> abstract concept. If order _really_ doesn't matter, then you wouldn't need
> to read the BQ data first. You could just flatten them together and run the
> pipeline like that. So I think there is some order-dependence that you want
> to represent at the data level.
>
> Kenn
>
>
>> I will explore using Wait.on(bigquery) before pub/sub read since I am not
>> sure if side input would be the best option here.
>>
>>
>> On Tue, Feb 28, 2023 at 8:44 AM Kenneth Knowles <k...@apache.org> wrote:
>>
>>> I'm also curious how much you depend on order to get the state contents
>>> right. The ordering of the side input will be arbitrary, and even the
>>> streaming input can have plenty of out of order messages. So I want to
>>> think about what are the data dependencies that result in the requirement
>>> of order. Or if there are none and you just want to know that all the past
>>> data has been processed, Niel's idea is one solution. It isn't parallel,
>>> though.
>>>
>>> Kenn
>>>
>>> On Mon, Feb 27, 2023 at 11:59 AM Reuven Lax <re...@google.com> wrote:
>>>
>>>> How large is this state spec stored in BQ? If the size isn't too large,
>>>> you can read it from BQ and make it a side input into the DoFn.
>>>>
>>>> On Mon, Feb 27, 2023 at 11:06 AM Sahil Modak <
>>>> smo...@paloaltonetworks.com> wrote:
>>>>
>>>>> We are trying to re-initialize our state specs in the BusinessLogic()
>>>>> DoFn from BQ.
>>>>> BQ has data about the state spec, and we would like to make sure that
>>>>> the state specs in our BusinessLogic() dofn are initialized before it
>>>>> starts consuming the pub/sub.
>>>>>
>>>>> This is for handling the case of redeployment of the dataflow jobs so
>>>>> that the states are preserved and the BusinessLogic() can work seamlessly
>>>>> as it was previously. All our dofns are operating in a global window and
>>>>> do
>>>>> not perform any aggregation.
>>>>>
>>>>> We are currently using Redis to preserve the state spec information
>>>>> but would like to explore using BQ as an alternative to Redis.
>>>>>
>>>>> On Fri, Feb 24, 2023 at 12:51 PM Kenneth Knowles <k...@apache.org>
>>>>> wrote:
>>>>>
>>>>>> My suggestion is to try to solve the problem in terms of what you
>>>>>> want to compute. Instead of trying to control the operational aspects
>>>>>> like
>>>>>> "read all the BQ before reading Pubsub" there is presumably some reason
>>>>>> that the BQ data naturally "comes first", for example if its timestamps
>>>>>> are
>>>>>> earlier or if there is a join or an aggregation that must include it.
>>>>>> Whenever you think you want to set up an operational dependency between
>>>>>> two
>>>>>> things that "happen" in a pipeline, it is often best to pivot your
>>>>>> thinking
>>>>>> to the data and what you are trying to compute, and the built-in
>>>>>> dependencies will solve the ordering problems.
>>>>>>
>>>>>> So - is there a way to describe your problem in terms of the data and
>>>>>> what you are trying to compute?
>>>>>>
>>>>>> Kenn
>>>>>>
>>>>>> On Fri, Feb 24, 2023 at 10:46 AM Reuven Lax via dev <
>>>>>> dev@beam.apache.org> wrote:
>>>>>>
>>>>>>> First PCollections are completely unordered, so there is no
>>>>>>> guarantee on what order you'll see events in the flattened PCollection.
>>>>>>>
>>>>>>> There may be ways to process the BigQuery data in a
>>>>>>> separate transform first, but it depends on the structure of the data.
>>>>>>> How
>>>>>>> large is the BigQuery table? Are you doing any windowed aggregations
>>>>>>> here?
>>>>>>>
>>>>>>> Reuven
>>>>>>>
>>>>>>> On Fri, Feb 24, 2023 at 10:40 AM Sahil Modak <
>>>>>>> smo...@paloaltonetworks.com> wrote:
>>>>>>>
>>>>>>>> Yes, this is a streaming pipeline.
>>>>>>>>
>>>>>>>> Some more details about existing implementation v/s what we want to
>>>>>>>> achieve.
>>>>>>>>
>>>>>>>> Current implementation:
>>>>>>>> Reading from pub-sub:
>>>>>>>>
>>>>>>>> Pipeline input = Pipeline.create(options);
>>>>>>>>
>>>>>>>> PCollection<String> pubsubStream = input.apply("Read From Pubsub",
>>>>>>>> PubsubIO.readMessagesWithAttributesAndMessageId()
>>>>>>>>
>>>>>>>> .fromSubscription(inputSubscriptionId))
>>>>>>>>
>>>>>>>>
>>>>>>>> Reading from bigquery:
>>>>>>>>
>>>>>>>> PCollection<String> bqStream = input.apply("Read from BQ", BigQueryIO
>>>>>>>> .readTableRows().fromQuery(bqQuery).usingStandardSql())
>>>>>>>>
>>>>>>>> .apply("JSon Transform", AsJsons.of(TableRow.class));
>>>>>>>>
>>>>>>>>
>>>>>>>> Merge the inputs:
>>>>>>>>
>>>>>>>> PCollection<String> mergedInput =
>>>>>>>> PCollectionList.of(pubsubStream).and(bqStream).apply("Merge Input",
>>>>>>>> Flatten.pCollections());
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>> Business Logic:
>>>>>>>>
>>>>>>>> mergedInput.apply("Business Logic", ParDo.of(new BusinessLogic()))
>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>> Above logic is what we use currently in our pipeline.
>>>>>>>>
>>>>>>>> We want to make sure that we read from BigQuery first & pass the
>>>>>>>> bqStream through our BusinessLogic() before we start consuming
>>>>>>>> pubsubStream.
>>>>>>>>
>>>>>>>> Is there a way to achieve this?
>>>>>>>>
>>>>>>>>
>>>>>>>> Thanks,
>>>>>>>>
>>>>>>>> Sahil
>>>>>>>>
>>>>>>>>
>>>>>>>> On Thu, Feb 23, 2023 at 10:21 PM Reuven Lax <re...@google.com>
>>>>>>>> wrote:
>>>>>>>>
>>>>>>>>> Can you explain this use case some more? Is this a streaming
>>>>>>>>> pipeline? If so, how are you reading from BigQuery?
>>>>>>>>>
>>>>>>>>> On Thu, Feb 23, 2023 at 10:06 PM Sahil Modak via dev <
>>>>>>>>> dev@beam.apache.org> wrote:
>>>>>>>>>
>>>>>>>>>> Hi,
>>>>>>>>>>
>>>>>>>>>> We have a requirement wherein we are consuming input from pub/sub
>>>>>>>>>> (PubSubIO) as well as BQ (BQIO)
>>>>>>>>>>
>>>>>>>>>> We want to make sure that we consume the BQ stream first before
>>>>>>>>>> we start consuming the data from pub-sub. Is there a way to achieve
>>>>>>>>>> this?
>>>>>>>>>> Can you please help with some code samples?
>>>>>>>>>>
>>>>>>>>>> Currently, we read data from big query using BigQueryIO into a
>>>>>>>>>> PCollection & also read data from pubsub using PubsubIO. We then use
>>>>>>>>>> the
>>>>>>>>>> flatten transform in this manner.
>>>>>>>>>>
>>>>>>>>>> PCollection pubsubKvPairs = reads from pubsub using PubsubIO
>>>>>>>>>> PCollection bigqueryKvPairs = reads from bigquery using
>>>>>>>>>> BigQueryIO
>>>>>>>>>>
>>>>>>>>>> kvPairs =
>>>>>>>>>> PCollectionList.of(pubsubKvPairs).and(bigqueryKvPairs).apply("Merge
>>>>>>>>>> Input", Flatten.pCollections());
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> Thanks,
>>>>>>>>>> Sahil
>>>>>>>>>>
>>>>>>>>>>
