WhereYouAre
I'm going to take an "Open-Design Software" approach to this project, please feel free to send me your two cents if you have an opinion.
Analysis
It would be nice, and should be easy, to provide an app that shows where your friends are. Many of these apps already exist, but they all break down when it comes to reaching critical mass: it's just too much trouble to get all your friends registered and receive their locations when you need them, as everyone is not going to run the app at the same time. Can we solve this problem well enough to make an app worth having?
Requirements
- Free and easy to configure
- Quickly start to track existing friends
- Make fast privacy and priority adjustments
- Obtain best-in-class location information
Design
Map view for traditional location display Arrow view for sexy fun location display Contacts view for fast privacy/prioritization changes
Implementation
(round4)
---- < > > [less][more][include_me(only on map)] [off][stlth] ---- click screen to get half-width menu (on opposite side of click) (start with closest friend) Group [All] (dropdown)(dont show if no groups are defined?) < showing top 5 users > < USERNAME > toggle "only this user" meetup stealth ignore plan route < priority 7 > ---
(round3)
Use cases ------------- 1 user starts app User gets updated friend locations User closes app 2 user goes offline (in app, prevents notifications) 3 user goes stealthmode 4 user changes friends priority (make this easy to do!) 5 user changes # tracked friends 6 user sets friend to ignore on/off 7 user sets friend to meetup on/off 8 user sets friend to stealth on/off 9 user pings friend 10 user adds friend 11 user deletes friend 12 import friends?
(round2)
REST summary ------------ every resource has to be discoverable via links basically a developer can learn the API with a browser also, with links, you can mingle resources from any REST api verbs GET - retrieve a specific resource DELETE - delete a specific resource PUT - update a specific resource POST - create a new resource and return the ID - neither safe nor idempotent you can repeat calls to GET/DELETE/PUT all day long if they fail complex functions (eg query and result) as resources create a query resource with a TTL add to it execute it (and auto-release?) release it (or let this happen automatically with server-side TTL cleanup)
how do we handle huge lists? like this? wya/users returns the first 10 users with a link to next 10 wya/users/range/11-20 a link to users 11-20
{resource}/edit should return an edit form (cool) - I think recess already does this?
authentication - use SSL with HTTP Basic Authentication, or SHA1 signature (ala Amazon S3)
wya API requirements ------------------------------------------ https put "my friends subscription" (on startup) https put "my location" every 15 seconds (may be "stealthmode") \ https get "my friends' locations" with ages (may be "stealthed")/ combine? https post "my new friend" with phone number and stealthstatus https put "my friend" with phone number and updated stealthstatus https delete "my friend" with phone number https put "ping this friend" with phone number https put "logoff"
NOT needed... ------------- put "i am running the app" (implied by [put my location]) put "my friend" (the server only tracks phone number, no editing available) any meetup or ignore state ignore is done by deleting friend meetup is done by client requesting pings
wya server requirements ------------------- track activeuser {phone,stealthmode,friendarray{phone,stealthed}} array collect nonstealthed friend locations "by any means necessary" priority: active app users, inactive app users, nonusers reply to API requests only report locations if not stealthed only report locations if under a day old? ping app users for meetups (if not ignored or stealthmoded) use TTL of 6 heartbeats, kill activeuser after that
wya client requirements ------------------- maintain complete friends list (even ignored) with prioritization ping server with location every 15 seconds adjust tracking to include "top n" friends "ignore all" mode (similar to "logoff server")
(round1)
all f's of all users running app need constant location ping f's must be shared with phone# as key server must track users' flist server must constantly work on getting f updates
user starts up app user logs in to server and sends friendlist server adds user to userlist, merges friendlist into totalfriendlist (w/refcount?) server should do its best to get all friends' locations ** this is a separate task from communicating with user ** user pings server with location, gets f updates ping every 15 seconds? only send updates if they have not been received by user? (how to get best performance?) user shuts down app (or times out) user is logged out of server
server f location collector use external services to poll for location for all f that are not running app ping every 15 seconds? users that are running app are all sending locations, no need to collect them
include occasional push check: if f owns app if f is not running app if f is in meetup push request to f1
<iph> <tdm_rest> <tdm_pusher> <apl> <loc_server> ----- ----- ----- ----- -----
REST Examples
- The best example I have to follow is the Twitter API. It *obviously* scales. It uses Basic Authentication, which sucks (everything is plaintext, holy shit). BETTER force it to use SSL.
- The other excellent example is the Amazon S3 API. Authentication is brilliant - it uses a SHA1 signature of the request, which MUST include a timestamp within the last 15 minutes. There is a set of rules for turning the request URL into the request string that is signed.
Signature = Base64( HMAC-SHA1( UTF-8-Encoding-Of( YourSecretAccessKeyID, StringToSign ) ) );