On Tue, May 22, 2018 at 10:51 PM Romain Manni-Bucau <rmannibu...@gmail.com>
wrote:
> How does it work on the pipeline side?
> Do you generate these "virtual" IO at build time to enable the fluent API
> to work not erasing generics?
>
Yeah - so I've already added support for injected element parameters (I'm
going to send an email to dev and users to make sure everyone is aware of
it), and that will be in the next Beam release. Basically you can now write:
DoFn<InputT, OutputT>() {
@ProcessElement public void process(InputT element,
OutputReceiver<OutputT> output) {
}
}
So there's almost no need for ProcessContext anymore (I would like to
eventually support side inputs as well, at which point the only reason to
keep ProcessContext around is backwards compatibility). Since process() is
not a virtual method, the "type checking" is done at pipeline construction
time instead of compile time.
> ex: SQL(row)->BigQuery(native) will not compile so we need a
> SQL(row)->BigQuery(row)
>
> Side note unrelated to Row: if you add another registry maybe a pretask is
> to ensure beam has a kind of singleton/context to avoid to duplicate it or
> not track it properly. These kind of converters will need a global close
> and not only per record in general:
> converter.init();converter.convert(row);....converter.destroy();, otherwise
> it easily leaks. This is why it can require some way to not recreate it. A
> quick fix, if you are in bytebuddy already, can be to add it to
> setup/teardown pby, being more global would be nicer but is more
> challenging.
>
Right now I'm using Pipeline as the container, so the lifetime is the life
of the Pipeline. Do you think this is the wrong lifetime?
>
> Romain Manni-Bucau
> @rmannibucau <https://twitter.com/rmannibucau> | Blog
> <https://rmannibucau.metawerx.net/> | Old Blog
> <http://rmannibucau.wordpress.com> | Github
> <https://github.com/rmannibucau> | LinkedIn
> <https://www.linkedin.com/in/rmannibucau> | Book
> <https://www.packtpub.com/application-development/java-ee-8-high-performance>
>
>
> Le mer. 23 mai 2018 à 07:22, Reuven Lax <re...@google.com> a écrit :
>
>> No - the only modules we need to add to core are the ones we choose to
>> add. For example, I will probably add a registration for
>> TableRow/TableSchema (GCP BigQuery) so these can work seamlessly with
>> schemas. However I will add that to the GCP module, so only someone
>> depending on that module need to pull in that dependency. The Java
>> ServiceLoader framework can be used by these modules to register schemas
>> for their types (we already do something similar for FileSystem and for
>> coders as well).
>>
>> BTW, right now the conversion back and forth between Row objects I'm
>> doing in the ByteBuddy generated bytecode that we generate in order to
>> invoke DoFns.
>>
>> Reuven
>>
>> On Tue, May 22, 2018 at 10:04 PM Romain Manni-Bucau <
>> rmannibu...@gmail.com> wrote:
>>
>>> Hmm, the pluggability part is close to what I wanted to do with
>>> JsonObject as a main API (to avoid to redo a "row" API and schema API)
>>> Row.as(Class<T>) sounds good but then, does it mean we'll get
>>> beam-sdk-java-row-jsonobject like modules (I'm not against, just trying to
>>> understand here)?
>>> If so, how an IO can use as() with the type it expects? Doesnt it lead
>>> to have a tons of these modules at the end?
>>>
>>> Romain Manni-Bucau
>>> @rmannibucau <https://twitter.com/rmannibucau> | Blog
>>> <https://rmannibucau.metawerx.net/> | Old Blog
>>> <http://rmannibucau.wordpress.com> | Github
>>> <https://github.com/rmannibucau> | LinkedIn
>>> <https://www.linkedin.com/in/rmannibucau> | Book
>>> <https://www.packtpub.com/application-development/java-ee-8-high-performance>
>>>
>>>
>>> Le mer. 23 mai 2018 à 04:57, Reuven Lax <re...@google.com> a écrit :
>>>
>>>> By the way Romain, if you have specific scenarios in mind I would love
>>>> to hear them. I can try and guess what exactly you would like to get out of
>>>> schemas, but it would work better if you gave me concrete scenarios that
>>>> you would like to work.
>>>>
>>>> Reuven
>>>>
>>>> On Tue, May 22, 2018 at 7:45 PM Reuven Lax <re...@google.com> wrote:
>>>>
>>>>> Yeah, what I'm working on will help with IO. Basically if you register
>>>>> a function with SchemaRegistry that converts back and forth between a type
>>>>> (say JsonObject) and a Beam Row, then it is applied by the framework
>>>>> behind
>>>>> the scenes as part of DoFn invocation. Concrete example: let's say I have
>>>>> an IO that reads json objects
>>>>> class MyJsonIORead extends PTransform<PBegin, JsonObject> {...}
>>>>>
>>>>> If you register a schema for this type (or you can also just set the
>>>>> schema directly on the output PCollection), then Beam knows how to convert
>>>>> back and forth between JsonObject and Row. So the next ParDo can look like
>>>>>
>>>>> p.apply(new MyJsonIORead())
>>>>> .apply(ParDo.of(new DoFn<JsonObject, T>....
>>>>> @ProcessElement void process(@Element Row row) {
>>>>> })
>>>>>
>>>>> And Beam will automatically convert JsonObject to a Row for processing
>>>>> (you aren't forced to do this of course - you can always ask for it as a
>>>>> JsonObject).
>>>>>
>>>>> The same is true for output. If you have a sink that takes in
>>>>> JsonObject but the transform before it produces Row objects (for instance
>>>>> -
>>>>> because the transform before it is Beam SQL), Beam can automatically
>>>>> convert Row back to JsonObject for you.
>>>>>
>>>>> All of this was detailed in the Schema doc I shared a few months ago.
>>>>> There was a lot of discussion on that document from various parties, and
>>>>> some of this API is a result of that discussion. This is also working in
>>>>> the branch JB and I were working on, though not yet integrated back to
>>>>> master.
>>>>>
>>>>> I would like to actually go further and make Row an interface and
>>>>> provide a way to automatically put a Row interface on top of any other
>>>>> object (e.g. JsonObject, Pojo, etc.) This won't change the way the user
>>>>> writes code, but instead of Beam having to copy and convert at each stage
>>>>> (e.g. from JsonObject to Row) it simply will create a Row object that uses
>>>>> the the JsonObject as its underlying storage.
>>>>>
>>>>> Reuven
>>>>>
>>>>> On Tue, May 22, 2018 at 11:37 AM Romain Manni-Bucau <
>>>>> rmannibu...@gmail.com> wrote:
>>>>>
>>>>>> Well, beam can implement a new mapper but it doesnt help for io. Most
>>>>>> of modern backends will take json directly, even javax one and it must
>>>>>> stay
>>>>>> generic.
>>>>>>
>>>>>> Then since json to pojo mapping is already done a dozen of times, not
>>>>>> sure it is worth it for now.
>>>>>>
>>>>>> Le mar. 22 mai 2018 20:27, Reuven Lax <re...@google.com> a écrit :
>>>>>>
>>>>>>> We can do even better btw. Building a SchemaRegistry where automatic
>>>>>>> conversions can be registered between schema and Java data types. With
>>>>>>> this
>>>>>>> the user won't even need a DoFn to do the conversion.
>>>>>>>
>>>>>>> On Tue, May 22, 2018, 10:13 AM Romain Manni-Bucau <
>>>>>>> rmannibu...@gmail.com> wrote:
>>>>>>>
>>>>>>>> Hi guys,
>>>>>>>>
>>>>>>>> Checked out what has been done on schema model and think it is
>>>>>>>> acceptable - regarding the json debate - if
>>>>>>>> https://issues.apache.org/jira/browse/BEAM-4381 can be fixed.
>>>>>>>>
>>>>>>>> High level, it is about providing a mainstream and not too
>>>>>>>> impacting model OOTB and JSON seems the most valid option for now, at
>>>>>>>> least
>>>>>>>> for IO and some user transforms.
>>>>>>>>
>>>>>>>> Wdyt?
>>>>>>>>
>>>>>>>> Le ven. 27 avr. 2018 18:36, Romain Manni-Bucau <
>>>>>>>> rmannibu...@gmail.com> a écrit :
>>>>>>>>
>>>>>>>>> Can give it a try end of may, sure. (holidays and work
>>>>>>>>> constraints will make it hard before).
>>>>>>>>>
>>>>>>>>> Le 27 avr. 2018 18:26, "Anton Kedin" <ke...@google.com> a écrit :
>>>>>>>>>
>>>>>>>>>> Romain,
>>>>>>>>>>
>>>>>>>>>> I don't believe that JSON approach was investigated very
>>>>>>>>>> thoroughIy. I mentioned few reasons which will make it not the best
>>>>>>>>>> choice
>>>>>>>>>> my opinion, but I may be wrong. Can you put together a design doc or
>>>>>>>>>> a
>>>>>>>>>> prototype?
>>>>>>>>>>
>>>>>>>>>> Thank you,
>>>>>>>>>> Anton
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> On Thu, Apr 26, 2018 at 10:17 PM Romain Manni-Bucau <
>>>>>>>>>> rmannibu...@gmail.com> wrote:
>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> Le 26 avr. 2018 23:13, "Anton Kedin" <ke...@google.com> a
>>>>>>>>>>> écrit :
>>>>>>>>>>>
>>>>>>>>>>> BeamRecord (Row) has very little in common with JsonObject (I
>>>>>>>>>>> assume you're talking about javax.json), except maybe some
>>>>>>>>>>> similarities of
>>>>>>>>>>> the API. Few reasons why JsonObject doesn't work:
>>>>>>>>>>>
>>>>>>>>>>> - it is a Java EE API:
>>>>>>>>>>> - Beam SDK is not limited to Java. There are probably
>>>>>>>>>>> similar APIs for other languages but they might not
>>>>>>>>>>> necessarily carry the
>>>>>>>>>>> same semantics / APIs;
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> Not a big deal I think. At least not a technical blocker.
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> - It can change between Java versions;
>>>>>>>>>>>
>>>>>>>>>>> No, this is javaee ;).
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> - Current Beam java implementation is an experimental
>>>>>>>>>>> feature to identify what's needed from such API, in the end
>>>>>>>>>>> we might end up
>>>>>>>>>>> with something similar to JsonObject API, but likely not
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> I dont get that point as a blocker
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> - ;
>>>>>>>>>>> - represents JSON, which is not an API but an object
>>>>>>>>>>> notation:
>>>>>>>>>>> - it is defined as unicode string in a certain format. If
>>>>>>>>>>> you choose to adhere to ECMA-404, then it doesn't sound like
>>>>>>>>>>> JsonObject can
>>>>>>>>>>> represent an Avro object, if I'm reading it right;
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> It is in the generator impl, you can impl an avrogenerator.
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> - doesn't define a type system (JSON does, but it's lacking):
>>>>>>>>>>> - for example, JSON doesn't define semantics for numbers;
>>>>>>>>>>> - doesn't define date/time types;
>>>>>>>>>>> - doesn't allow extending JSON type system at all;
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> That is why you need a metada object, or simpler, a schema with
>>>>>>>>>>> that data. Json or beam record doesnt help here and you end up on
>>>>>>>>>>> the same
>>>>>>>>>>> outcome if you think about it.
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> - lacks schemas;
>>>>>>>>>>>
>>>>>>>>>>> Jsonschema are standard, widely spread and tooled compared to
>>>>>>>>>>> alternative.
>>>>>>>>>>>
>>>>>>>>>>> You can definitely try loosen the requirements and define
>>>>>>>>>>> everything in JSON in userland, but the point of Row/Schema is to
>>>>>>>>>>> avoid it
>>>>>>>>>>> and define everything in Beam model, which can be extended, mapped
>>>>>>>>>>> to JSON,
>>>>>>>>>>> Avro, BigQuery Schemas, custom binary format etc., with same
>>>>>>>>>>> semantics
>>>>>>>>>>> across beam SDKs.
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> This is what jsonp would allow with the benefit of a natural
>>>>>>>>>>> pojo support through jsonb.
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> On Thu, Apr 26, 2018 at 12:28 PM Romain Manni-Bucau <
>>>>>>>>>>> rmannibu...@gmail.com> wrote:
>>>>>>>>>>>
>>>>>>>>>>>> Just to let it be clear and let me understand: how is
>>>>>>>>>>>> BeamRecord different from a JsonObject which is an API without
>>>>>>>>>>>> implementation (not event a json one OOTB)? Advantage of json
>>>>>>>>>>>> *api* are
>>>>>>>>>>>> indeed natural mapping (jsonb is based on jsonp so no new binding
>>>>>>>>>>>> to
>>>>>>>>>>>> reinvent) and simple serialization (json+gzip for ex, or avro if
>>>>>>>>>>>> you want
>>>>>>>>>>>> to be geeky).
>>>>>>>>>>>>
>>>>>>>>>>>> I fail to see the point to rebuild an ecosystem ATM.
>>>>>>>>>>>>
>>>>>>>>>>>> Le 26 avr. 2018 19:12, "Reuven Lax" <re...@google.com> a
>>>>>>>>>>>> écrit :
>>>>>>>>>>>>
>>>>>>>>>>>>> Exactly what JB said. We will write a generic conversion from
>>>>>>>>>>>>> Avro (or json) to Beam schemas, which will make them work
>>>>>>>>>>>>> transparently
>>>>>>>>>>>>> with SQL. The plan is also to migrate Anton's work so that POJOs
>>>>>>>>>>>>> works
>>>>>>>>>>>>> generically for any schema.
>>>>>>>>>>>>>
>>>>>>>>>>>>> Reuven
>>>>>>>>>>>>>
>>>>>>>>>>>>> On Thu, Apr 26, 2018 at 1:17 AM Jean-Baptiste Onofré <
>>>>>>>>>>>>> j...@nanthrax.net> wrote:
>>>>>>>>>>>>>
>>>>>>>>>>>>>> For now we have a generic schema interface. Json-b can be an
>>>>>>>>>>>>>> impl, avro could be another one.
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> Regards
>>>>>>>>>>>>>> JB
>>>>>>>>>>>>>> Le 26 avr. 2018, à 12:08, Romain Manni-Bucau <
>>>>>>>>>>>>>> rmannibu...@gmail.com> a écrit:
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> Hmm,
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> avro has still the pitfalls to have an uncontrolled stack
>>>>>>>>>>>>>>> which brings way too much dependencies to be part of any API,
>>>>>>>>>>>>>>> this is why I proposed a JSON-P based API (JsonObject) with
>>>>>>>>>>>>>>> a custom beam entry for some metadata (headers "à la Camel").
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> Romain Manni-Bucau
>>>>>>>>>>>>>>> @rmannibucau <https://twitter.com/rmannibucau> | Blog
>>>>>>>>>>>>>>> <https://rmannibucau.metawerx.net/> | Old Blog
>>>>>>>>>>>>>>> <http://rmannibucau.wordpress.com> | Github
>>>>>>>>>>>>>>> <https://github.com/rmannibucau> | LinkedIn
>>>>>>>>>>>>>>> <https://www.linkedin.com/in/rmannibucau> | Book
>>>>>>>>>>>>>>> <https://www.packtpub.com/application-development/java-ee-8-high-performance>
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> 2018-04-26 9:59 GMT+02:00 Jean-Baptiste Onofré <
>>>>>>>>>>>>>>> j...@nanthrax.net>:
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> Hi Ismael
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> You mean directly in Beam SQL ?
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> That will be part of schema support: generic record could
>>>>>>>>>>>>>>>> be one of the payload with across schema.
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> Regards
>>>>>>>>>>>>>>>> JB
>>>>>>>>>>>>>>>> Le 26 avr. 2018, à 11:39, "Ismaël Mejía" <
>>>>>>>>>>>>>>>> ieme...@gmail.com> a écrit:
>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>> Hello Anton,
>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>> Thanks for the descriptive email and the really useful work.
>>>>>>>>>>>>>>>>> Any plans
>>>>>>>>>>>>>>>>> to tackle PCollections of GenericRecord/IndexedRecords? it
>>>>>>>>>>>>>>>>> seems Avro
>>>>>>>>>>>>>>>>> is a natural fit for this approach too.
>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>> Regards,
>>>>>>>>>>>>>>>>> Ismaël
>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>> On Wed, Apr 25, 2018 at 9:04 PM, Anton Kedin
>>>>>>>>>>>>>>>>> <ke...@google.com> wrote:
>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> Hi,
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> I want to highlight a couple of improvements to Beam SQL we
>>>>>>>>>>>>>>>>>> have been
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> working on recently which are targeted to make Beam SQL API
>>>>>>>>>>>>>>>>>> easier to use.
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> Specifically these features simplify conversion of Java
>>>>>>>>>>>>>>>>>> Beans and JSON
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> strings to Rows.
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> Feel free to try this and send any bugs/comments/PRs my way.
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> **Caveat: this is still work in progress, and has known
>>>>>>>>>>>>>>>>>> bugs and incomplete
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> features, see below for details.**
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> Background
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> Beam SQL queries can only be applied to PCollection<Row>.
>>>>>>>>>>>>>>>>>> This means that
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> users need to convert whatever PCollection elements they
>>>>>>>>>>>>>>>>>> have to Rows before
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> querying them with SQL. This usually requires manually
>>>>>>>>>>>>>>>>>> creating a Schema and
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> implementing a custom conversion PTransform<PCollection<
>>>>>>>>>>>>>>>>>> Element>,
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> PCollection<Row>> (see Beam SQL Guide).
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> The improvements described here are an attempt to reduce
>>>>>>>>>>>>>>>>>> this overhead for
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> few common cases, as a start.
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> Status
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> Introduced a InferredRowCoder to automatically generate
>>>>>>>>>>>>>>>>>> rows from beans.
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> Removes the need to manually define a Schema and Row
>>>>>>>>>>>>>>>>>> conversion logic;
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> Introduced JsonToRow transform to automatically parse JSON
>>>>>>>>>>>>>>>>>> objects to Rows.
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> Removes the need to manually implement a conversion logic;
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> This is still experimental work in progress, APIs will
>>>>>>>>>>>>>>>>>> likely change;
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> There are known bugs/unsolved problems;
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> Java Beans
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> Introduced a coder which facilitates Rows generation from
>>>>>>>>>>>>>>>>>> Java Beans.
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> Reduces the overhead to:
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>> /** Some user-defined Java Bean */
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>> class JavaBeanObject implements Serializable {
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>> String getName() { ... }
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>> }
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>> // Obtain the objects:
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>> PCollection<JavaBeanObject> javaBeans = ...;
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>> // Convert to Rows and apply a SQL query:
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>> PCollection<Row> queryResult =
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>> javaBeans
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>> .setCoder(InferredRowCoder.
>>>>>>>>>>>>>>>>>>> ofSerializable(JavaBeanObject.
>>>>>>>>>>>>>>>>>>> class))
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>> .apply(BeamSql.query("SELECT name FROM PCOLLECTION"));
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> Notice, there is no more manual Schema definition or custom
>>>>>>>>>>>>>>>>>> conversion
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> logic.
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> Links
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> example;
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> InferredRowCoder;
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> test;
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> JSON
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> Introduced JsonToRow transform. It is possible to query a
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> PCollection<String> that contains JSON objects like this:
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>> // Assuming JSON objects look like this:
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>> // { "type" : "foo", "size" : 333 }
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>> // Define a Schema:
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>> Schema jsonSchema =
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>> Schema
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>> .builder()
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>> .addStringField("type")
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>> .addInt32Field("size")
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>> .build();
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>> // Obtain PCollection of the objects in JSON format:
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>> PCollection<String> jsonObjects = ...
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>> // Convert to Rows and apply a SQL query:
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>> PCollection<Row> queryResults =
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>> jsonObjects
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>> .apply(JsonToRow.withSchema(
>>>>>>>>>>>>>>>>>>> jsonSchema))
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>> .apply(BeamSql.query("SELECT type, AVG(size) FROM
>>>>>>>>>>>>>>>>>>> PCOLLECTION GROUP BY
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>> type"));
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> Notice, JSON to Row conversion is done by JsonToRow
>>>>>>>>>>>>>>>>>> transform. It is
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> currently required to supply a Schema.
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> Links
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> JsonToRow;
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> test/example;
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> Going Forward
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> fix bugs (BEAM-4163, BEAM-4161 ...)
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> implement more features (BEAM-4167, more types of objects);
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> wire this up with sources/sinks to further simplify SQL API;
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> Thank you,
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>> Anton
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>
>>>>>>>>>>>
