Actually, having separate streams for each tag is what I'm suggesting, I'm just trying to determine when best to create them. If a client requests all the streams, they will all be created. Should we talk about not streaming individual tags at all? Maybe put a limit on the number of streams a client can have open? I'm not sure what the performance impact will look like.
Also, I need to amend the original email. I think that because we are using Lift Sessions, we will be killing off the session and the streams attached to it after a period of time. So I think option 2 and option 4 are the same or very similar. Ethan On Mon, Dec 14, 2009 at 11:39 PM, Richard Hirsch <[email protected]> wrote: > Yes it sounds reasonable. I don't think it makes much sense to have > separate streams for each tag, etc... > > I agree option 2 is the best choice. > > D. > > On Mon, Dec 14, 2009 at 12:29 AM, Ethan Jewett <[email protected]> wrote: >> All, >> >> In the cwiki, we've documented 5 parts of the API we would like to >> stream. They are briefly: user timeline, tags, tracks, conversations, >> and pools (and possibly the public timeline) >> >> Of these, one has been implemented: user timeline >> >> Today I've been able to take some time to start digging into what >> needs to be done to implement the rest of the streaming interfaces. >> The way the user timeline streaming interface is implemented in the >> old and new APIs is the same (because I just copied and slightly >> modified the code). The basic idea is that when a session is created, >> the streaming API starts "listening" for new messages. When the user >> makes a request to the streaming interface for new messages, all the >> messages that have built up are delivered. >> >> This approach poses some significant problems for other types of >> streams. For example, if we were going to stream tags in this manner, >> we would end up creating a listener for every single active tag in the >> system at the time the user initiates a session. We would also have >> the dilemma of creating listeners for new tags as the tags are created >> in the middle of a session. >> >> As such, I'm thinking of implementing the other streaming interfaces >> differently. Instead of creating listeners when the session is >> initiated, I'll create them when the first streaming request for a >> tag, pool, track, or conversation comes in. These listeners would then >> live on for the rest of the session. This is, I think the best of >> several options. >> >> To summarize the options available: >> >> 1. Create listeners for everything at the beginning of the session - >> not efficient, suffers from difficulties with new tags, pools, etc. >> created during the session >> >> 2. Create listeners for streams as the user requests them and have >> these listeners live on for the rest of the session >> >> 3. Create disposable listeners for each streaming/long-polling request >> that are destroyed once the request is answered - this is problematic >> because messages that occur between requests will be missed >> >> 4. Variation of option 2 and 3: Create listeners for streams as the >> user requests them and have these listeners life on for the rest of >> the session or a specific period of time, whichever comes first (so >> the user would have to make occasional requests to ensure the >> continuity of the message stream) - I think this is over-complicated >> and potentially confusing to developers, but could be a good option if >> we run into performance problems with option 2 >> >> >> What we'll be left with is that the user timeline will use option 1 >> and the other streams will use option 2. The user timeline might >> switch to option 2 at some point in the future. >> >> And that was all a very long way of saying, does that sound reasonable >> to everyone? >> >> Ethan >> >
