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Posted to dev@calcite.apache.org by "ptr.bojko@gmail.com" <pt...@gmail.com> on 2017/10/31 13:56:06 UTC
Problems with exposing calcite through avatica and custom servlet
Hello,
My task is to expose calcite-made schema through avatica. I've encountered
some stopper here. Some details I've placed at stackoverflow - but no help
there.
https://stackoverflow.com/questions/46792353/expose-calcite-based-db-through-avatica-by-custom-servlet
Could you, please, make some hints on where could I made a mistake in my
thinking on the problem?
Thanks in advance for help!
Piotr Bojko
Re: Problems with exposing calcite through avatica and custom servlet
Posted by Julian Hyde <jh...@apache.org>.
Glad you found a solution — and many thanks for sharing it on this list; it will help anyone who runs into the same problem.
> On Nov 2, 2017, at 8:42 AM, ptr.bojko@gmail.com wrote:
>
> Sorry for yet another mail in my minor case.
>
> Just to inform You that my assumptions where correct. Meta created from
> Driver based on CalciteConnection is not compatible with LocalService
> needed for avatica. After switching to JDBCMeta implementation from the
> avatica internal test project - I've managed to connect with squirrel.
>
> Wow :)
>
>
> Again - thank you for calcite
> P
>
> On Thu, Nov 2, 2017 at 2:32 PM ptr.bojko@gmail.com <pt...@gmail.com>
> wrote:
>
>> Hello Julian,
>>
>> I am pretty sure that this is not an container issue, ie classloader etc.
>> Error stack is eated by avatica AbstractHandler implementation, thus no
>> stack presented in SO. But I've attached the code with the suspected issue
>> - org.apache.calcite.avatica.Meta.Frame.toProto method.
>>
>> Mentioned method handles only arrays and iterables but not
>> MetaImpl$MetaTableType which is placed under Meta.rows property. This is
>> why I rather believe that I've bootstrap calcite with avatica incorrectly
>> itself, despite the container used.
>>
>> For handling the protobuf RCPs I've used following stack:
>>
>> 1. custom servlet
>> 2. org.apache.calcite.avatica.remote.ProtobufHandler - for handling
>> requests
>> 3. org.apache.calcite.avatica.remote.LocalService under the handler
>> 4. DRIVER.createMeta((AvaticaConnection) connection) - as a Meta for
>> LocalService
>> 5. CalciteConnection - for Meta
>> 6. connection created as from examples from calcite site from inline
>> JSON
>>
>> My assumption is that somewhere in this stack exists some incompatibility,
>> ie Meta created from Driver from CalciteConnection is not compatible with
>> LocalService needed for ProtobufHandler.
>>
>> Regads and keep up good work - calcite is so advanced library :)
>>
>> Peter
>>
>> On Tue, Oct 31, 2017 at 4:33 PM Julian Hyde <jh...@apache.org> wrote:
>>
>>> The SO question doesn’t have an error stack but I recall seeing previous
>>> versions of this question where there were what looked like class-loader
>>> issues - class-not-found or similar. I know you’re struggling here, but I’m
>>> afraid don’t have time to try to set up your environment to try to
>>> reproduce those issues. I do know that these classes work together just
>>> fine in the environment we use for testing. Obviously this is a simpler
>>> environment, and not useful to you (though not that simple - I recall that
>>> Avatica has tests that use jetty). A next step for you might be to start
>>> with one of these simple environments and add complexity until something
>>> breaks; then you’ll know where the conflict is coming from.
>>>
>>> Julian
>>>
>>>
>>>
>>>> On Oct 31, 2017, at 6:56 AM, ptr.bojko@gmail.com wrote:
>>>>
>>>> Hello,
>>>>
>>>> My task is to expose calcite-made schema through avatica. I've
>>> encountered
>>>> some stopper here. Some details I've placed at stackoverflow - but no
>>> help
>>>> there.
>>>>
>>>>
>>> https://stackoverflow.com/questions/46792353/expose-calcite-based-db-through-avatica-by-custom-servlet
>>>>
>>>> Could you, please, make some hints on where could I made a mistake in my
>>>> thinking on the problem?
>>>>
>>>> Thanks in advance for help!
>>>>
>>>> Piotr Bojko
>>>
>>>
Re: Problems with exposing calcite through avatica and custom servlet
Posted by "ptr.bojko@gmail.com" <pt...@gmail.com>.
Sorry for yet another mail in my minor case.
Just to inform You that my assumptions where correct. Meta created from
Driver based on CalciteConnection is not compatible with LocalService
needed for avatica. After switching to JDBCMeta implementation from the
avatica internal test project - I've managed to connect with squirrel.
Wow :)
Again - thank you for calcite
P
On Thu, Nov 2, 2017 at 2:32 PM ptr.bojko@gmail.com <pt...@gmail.com>
wrote:
> Hello Julian,
>
> I am pretty sure that this is not an container issue, ie classloader etc.
> Error stack is eated by avatica AbstractHandler implementation, thus no
> stack presented in SO. But I've attached the code with the suspected issue
> - org.apache.calcite.avatica.Meta.Frame.toProto method.
>
> Mentioned method handles only arrays and iterables but not
> MetaImpl$MetaTableType which is placed under Meta.rows property. This is
> why I rather believe that I've bootstrap calcite with avatica incorrectly
> itself, despite the container used.
>
> For handling the protobuf RCPs I've used following stack:
>
> 1. custom servlet
> 2. org.apache.calcite.avatica.remote.ProtobufHandler - for handling
> requests
> 3. org.apache.calcite.avatica.remote.LocalService under the handler
> 4. DRIVER.createMeta((AvaticaConnection) connection) - as a Meta for
> LocalService
> 5. CalciteConnection - for Meta
> 6. connection created as from examples from calcite site from inline
> JSON
>
> My assumption is that somewhere in this stack exists some incompatibility,
> ie Meta created from Driver from CalciteConnection is not compatible with
> LocalService needed for ProtobufHandler.
>
> Regads and keep up good work - calcite is so advanced library :)
>
> Peter
>
> On Tue, Oct 31, 2017 at 4:33 PM Julian Hyde <jh...@apache.org> wrote:
>
>> The SO question doesn’t have an error stack but I recall seeing previous
>> versions of this question where there were what looked like class-loader
>> issues - class-not-found or similar. I know you’re struggling here, but I’m
>> afraid don’t have time to try to set up your environment to try to
>> reproduce those issues. I do know that these classes work together just
>> fine in the environment we use for testing. Obviously this is a simpler
>> environment, and not useful to you (though not that simple - I recall that
>> Avatica has tests that use jetty). A next step for you might be to start
>> with one of these simple environments and add complexity until something
>> breaks; then you’ll know where the conflict is coming from.
>>
>> Julian
>>
>>
>>
>> > On Oct 31, 2017, at 6:56 AM, ptr.bojko@gmail.com wrote:
>> >
>> > Hello,
>> >
>> > My task is to expose calcite-made schema through avatica. I've
>> encountered
>> > some stopper here. Some details I've placed at stackoverflow - but no
>> help
>> > there.
>> >
>> >
>> https://stackoverflow.com/questions/46792353/expose-calcite-based-db-through-avatica-by-custom-servlet
>> >
>> > Could you, please, make some hints on where could I made a mistake in my
>> > thinking on the problem?
>> >
>> > Thanks in advance for help!
>> >
>> > Piotr Bojko
>>
>>
Re: Problems with exposing calcite through avatica and custom servlet
Posted by "ptr.bojko@gmail.com" <pt...@gmail.com>.
Hello Julian,
I am pretty sure that this is not an container issue, ie classloader etc.
Error stack is eated by avatica AbstractHandler implementation, thus no
stack presented in SO. But I've attached the code with the suspected issue
- org.apache.calcite.avatica.Meta.Frame.toProto method.
Mentioned method handles only arrays and iterables but not
MetaImpl$MetaTableType which is placed under Meta.rows property. This is
why I rather believe that I've bootstrap calcite with avatica incorrectly
itself, despite the container used.
For handling the protobuf RCPs I've used following stack:
1. custom servlet
2. org.apache.calcite.avatica.remote.ProtobufHandler - for handling
requests
3. org.apache.calcite.avatica.remote.LocalService under the handler
4. DRIVER.createMeta((AvaticaConnection) connection) - as a Meta for
LocalService
5. CalciteConnection - for Meta
6. connection created as from examples from calcite site from inline JSON
My assumption is that somewhere in this stack exists some incompatibility,
ie Meta created from Driver from CalciteConnection is not compatible with
LocalService needed for ProtobufHandler.
Regads and keep up good work - calcite is so advanced library :)
Peter
On Tue, Oct 31, 2017 at 4:33 PM Julian Hyde <jh...@apache.org> wrote:
> The SO question doesn’t have an error stack but I recall seeing previous
> versions of this question where there were what looked like class-loader
> issues - class-not-found or similar. I know you’re struggling here, but I’m
> afraid don’t have time to try to set up your environment to try to
> reproduce those issues. I do know that these classes work together just
> fine in the environment we use for testing. Obviously this is a simpler
> environment, and not useful to you (though not that simple - I recall that
> Avatica has tests that use jetty). A next step for you might be to start
> with one of these simple environments and add complexity until something
> breaks; then you’ll know where the conflict is coming from.
>
> Julian
>
>
>
> > On Oct 31, 2017, at 6:56 AM, ptr.bojko@gmail.com wrote:
> >
> > Hello,
> >
> > My task is to expose calcite-made schema through avatica. I've
> encountered
> > some stopper here. Some details I've placed at stackoverflow - but no
> help
> > there.
> >
> >
> https://stackoverflow.com/questions/46792353/expose-calcite-based-db-through-avatica-by-custom-servlet
> >
> > Could you, please, make some hints on where could I made a mistake in my
> > thinking on the problem?
> >
> > Thanks in advance for help!
> >
> > Piotr Bojko
>
>
Re: Problems with exposing calcite through avatica and custom servlet
Posted by Julian Hyde <jh...@apache.org>.
The SO question doesn’t have an error stack but I recall seeing previous versions of this question where there were what looked like class-loader issues - class-not-found or similar. I know you’re struggling here, but I’m afraid don’t have time to try to set up your environment to try to reproduce those issues. I do know that these classes work together just fine in the environment we use for testing. Obviously this is a simpler environment, and not useful to you (though not that simple - I recall that Avatica has tests that use jetty). A next step for you might be to start with one of these simple environments and add complexity until something breaks; then you’ll know where the conflict is coming from.
Julian
> On Oct 31, 2017, at 6:56 AM, ptr.bojko@gmail.com wrote:
>
> Hello,
>
> My task is to expose calcite-made schema through avatica. I've encountered
> some stopper here. Some details I've placed at stackoverflow - but no help
> there.
>
> https://stackoverflow.com/questions/46792353/expose-calcite-based-db-through-avatica-by-custom-servlet
>
> Could you, please, make some hints on where could I made a mistake in my
> thinking on the problem?
>
> Thanks in advance for help!
>
> Piotr Bojko