Got it! Thanks! :)
On Thu, Oct 16, 2014 at 4:26 PM, Chin Huang <[email protected]> wrote:
> The tuples emitted from the join must have these fields:
>
> 1. First, the fields you are joining on.
> 2. Next, the other fields, in the same order as the streams passed to the
> join method and in the same order as the input tuple fields.
>
> For your example, the join output tuple fields would be
>
> new Fields("messageId", "datatype", "provider")
>
> On Thu, Oct 16, 2014 at 7:25 AM, Thiago Souza <[email protected]>
> wrote:
>
>> I'm a Storm newbie trying to learn it. Could someone please help me?
>> Consider the following snippet:
>>
>> TridentTopology builder = new TridentTopology();
>>
>> // Random data generated with a random 'messageId'
>> Stream inputStream = builder.newStream("data-supply", new
>> RandomDataGenerator() /* this extends BaseRichSpout */);
>>
>> // Load 'Datatype' referenced by datatypeId from external source
>>
>> Stream datatypeStream = inputStream.each(new Fields("datatypeId"),
>> new DatatypeLoader(), new Fields("datatype")).
>>
>> project(new Fields("messageId", "datatype"));
>>
>> // Load 'Provider' referenced by providerId from external source
>>
>> Stream providerStream = inputStream.each(new Fields("providerId"),
>> new ProviderLoader(), new Fields("provider")).
>>
>> project(new Fields("messageId", "provider"));
>>
>> // Join both streams on original 'messageId'
>> builder.join(providerStream, new Fields("messageId"),
>> datatypeStream, new Fields("messageId"),
>> new Fields("datatype", "provider")).
>>
>> each(new Fields("datatype", "provider"), new Print()); // Print the
>> result
>>
>>
>> I expected to get a Tuple with both 'Datatype' and 'Provider' previoulsy
>> loaded, but what I get is a Tuple with either one, depending on which is
>> the first argument of the 'join' method (in this case 'providerStream').
>>
>> Am I doing something wrong or maybe with a misconcept of how storm works?
>>
>> Thanks,
>> Thiago Souza
>>
>
>
