Very nice, and thank you for the feedback.
> On 28 Dec 2018, at 23:16, Jimmie Houchin <jlhouc...@gmail.com> wrote:
>
> On 12/27/18 9:00 AM, Sven Van Caekenberghe wrote:
>> Hi Jimmie,
>>
>>> On 27 Dec 2018, at 15:15, Jimmie Houchin <jlhouc...@gmail.com> wrote:
>>>
>>> Hello,
>>>
>>> I am wanting to subscribe to a perpetual stream of JSON data in my app. I
>>> have failed to find an example which helps me understand how to do
>>> so. It may be there but I have not discovered it.
>>>
>>> How do I do something like that? A curl example from the website.
>>>
>>> curl \
>>> -H "Authorization: abcdefg?????" \
>>> "https://stream-mystreamingsite.com/stream?query=whatIwant";
>>> Response Headers
>>> HTTP/1.1 200 OK
>>> Access-Control-Allow-Headers: Authorization, Content-Type,
>>> Accept-Datetime-Format
>>> Access-Control-Allow-Methods: PUT, PATCH, POST, GET, OPTIONS, DELETE
>>> Access-Control-Allow-Origin: *
>>> Content-Type: application/octet-stream
>>>
>>>
>>> After subscribing to the stream I will need to get and access the JSON data
>>> so that my app can process it.
>>>
>>> Any help and wisdom greatly appreciated.
>>>
>>> Thanks.
>>>
>>> Jimmie
>> The client and server part of the WebSockets extension to Zinc HTTP
>> Components already supports similar functionality, so this is certainly
>> doable.
>>
>> Unless you can give me a public end point to test, I can only write some
>> untested pseudo code.
>>
>> | client reader |
>> client := ZnClient new.
>> client url: 'https://stream-mystreamingsite.com/stream?query=whatIwant'.
>> client streaming: true.
>> client headerAt: 'Authorization' put: 'xxx'.
>> client get.
>> reader := NeoJSONReader on: (ZnCharacterReadStream on: client contents).
>> [ reader atEnd] whileFalse: [ reader next ].
>> reader close.
>> client close.
>>
>> Be sure to tell us how you got it working.
>>
>> HTH,
>>
>> Sven
>
> Hello Sven,
>
> Thanks for your help.
>
> The server I am connecting to requires an account to access. But you provided
> sufficient information to get me going. Thanks.
>
> This is for a Trading Application. I am a ways off before ready for
> releasing. I will open source when it is usable and cleaned up enough from
> personal code.
>
> Currently I have named it SmallTrader, hence the ST prefix for classes.
>
> I have an STClient class which subclasses ZnClient and sets it up with the
> necessary account authorization.
>
> Below is the STPriceStream#mainLoop method.
>
> Basically it is populating some OrderedCollections in the STPriceStream which
> are available to the app's mainLoop.
>
> It is working perfectly. I currently have it printing out data to stdout so
> that I can watch the data it collects to visually understand what is
> happening.
>
> The connection below is the instance of the class which connects to this
> specific broker. Since connections are specific to a broker I am putting all
> of the parsing into ST objects such as STPrice and STCandle in the broker
> specific class as it understands what the broker returns. This will allow my
> app to be able to use different brokers simply by changing which connection
> class we call. Currently I am writing for one specific one where my account
> is located. But I want to be able to add brokers in time.
>
> Thanks again for your help.
>
> mainLoop
> | delay pricesStream reader |
> delay := (Duration milliSeconds: 100) asDelay.
> minuteDateTime := STCandle datetimeMinute: (DateAndTime now asUTC).
> pricesStream := connection newPriceStreamConnectionForInstruments:
> instruments.
> pricesStream get.
> reader := STONReader on: (ZnCharacterReadStream on: pricesStream
> contents).
> [ reader atEnd] whileFalse: [
> stop
> ifFalse: [ | price |
> price := connection pricesStreamNextPrice: (reader next).
> price ifNotNil: [
> prices add: price.
> price datetimeMinute = minuteDateTime
> ifTrue: [ minutePrices add: price ]
> ifFalse: [ self processMinutePrices: price ]]]
> ifTrue: [
> reader close
> ^ self ].
> delay wait ].
>
>
> Jimmie
