Add ability to search history by conversation content, not just name (issue #67)

[douglasrapp]

Primary change is moving search logic from the client (in-browser mini-mongo db) to the server, in order to get around pub-sub issues encountered when trying to search all messages of all the user's joined rooms.

Modified the search logic to also search the contents of the rooms of which the user is a member when a flag is set. Added a checkbox option to the webpage for setting and clearing that flag.

Added 'debounce' function to the the 'keyup' event to try to protect the server from too many calls. Otherwise, an RPC call would get sent to the server every time a user hit a key. Now, it will wait until after the user has stopped typing for 200ms before sending the search request to the server.

Also fixed an issue where clicking on a search result item did not route to that room.

[douglasrapp]

Previously was going to move history search back to the client rather than the server after subscription change introduced in issue #68 (pull request #88). However, on further analysis, due to issues with subscribing to the messages collection, as well as concerns about synchronizing ALL message history of ALL rooms of which the user is a member with the browser (could be very large), I think it makes sense to leave the search function on the server.

Therefore, this PR is once again ready for review.

[rwakida]

Direct message search history result only shows @ in title

[douglasrapp]

Ah, ok. Looks like a discrepancy from how Rocket was searching subscriptions on the client, and this is now searching rooms on the server. Since direct message rooms do not have a 'name' field, this is showing up blank.

[douglasrapp]

Looks like it can be fixed by searching subscriptions instead of rooms. Originally, I was under the impression that we'd need to search rooms for the use case of a user "leaving" a room, but later wanting to find it again.

But, looking closer, I see that idea of "leaving" a room only (currently) applies to channels, and when you do leave a channel, not only is the subscription removed, but the user is pulled from the channel membership. Since I'm currently searching rooms based on membership, it looks like it's not gaining anything.

Are there any other cases that might make us want to search rooms vs subscriptions??

[douglasrapp]

I went ahead and made the change to search the ChatSubscription collection instead of the ChatRoom collection for matching rooms. So the issue with direct messages showing up as just an '@' symbol is fixed.

[rwakida]

👍 I can see the user's name in the title.