I'm using the Asana REST API to iterate over workspaces, projects, and tasks. After I achieved the initial crawl over the data, I was surprised to see that I only retrieved the top-level tasks. Since I am required to provide the workspace and project information, I was hoping not to have to recurse any deeper. It appears that I can recurse on a single task with the \subtasks endpoint and re-query... wash/rinse/repeat... but that amounts to a potentially massive number of REST calls (one for each subtask to see if they, in turn, have subtasks to query - and so on).
I can partially mitigate this by adding to the opt_fields query parameter something like:
&opt_fields=subtasks,subtasks.subtasks
However, this doesn't scale well. It means I have to elongate the query for each layer of depth. I suppose I could say "don't put tasks deeper than x layers deep" - but that seems to fly in the face of Asana's functionality and design. Also, since I need lots of other properties, it requires me to make a secondary query for each node in the hierarchy to gather those. Ugh.
I can use the path method to try to mitigate this a bit:
&opt_fields=(this|subtasks).(id|name|etc...)
but again, I have to do this for every layer of depth. That's impractical.
There's documentation about this great REPEATER + operator. Supposedly it would work like this:
&opt_fields=this.subtasks+.name
That is supposed to apply to ALL subtasks anywhere in the hierarchy. In practice, this is completely broken, and the REST API chokes and returns only the ids of the top-level tasks. :( Apparently their documentation is just wrong here.
The only method that seems remotely functional (if not practical) is to iterate first on the top-level tasks, being sure to include opt_fields=subtasks. Whenever this is a non-empty array, I would need to recurse on that task, query for its subtasks, and continue in that manner, until I reach a null subtasks array. This could be of arbitrary depth. In practice, the first REST call yields me (hopefully) the largest number of tasks, so the individual recursion may be mitigated by real data... but it's a heck of an assumption.
I also noticed that the limit parameter applied ONLY to the top-level tasks. If I choose to expand the subtasks, say. I could get a thousand tasks back instead of 100. The call could timeout if the data is too large. The safest thing to do would be to only request the ids of subtasks until recursion, and as always, ask for all the desired top-level properties at that time.
All of this seems incredibly wasteful - what I really want is a flat list of tasks which include the parent.id and possibly a list of subtasks.id - but I don't want to query for them hierarchically. I also want to page my queries with rational data sizes in mind. I'd like to get 100 tasks at a time until Asana runs out - but that doesn't seem possible, since the limit only applies to top-level items.
Unfortunately the repeater didn't solve my problem, since it just doesn't work. What are other people doing to solve this problem? And, secondarily, can anyone with intimate Asana insight provide any hope of getting a better way to query?
While I'm at it, a suggested way to design this: the task endpoint should not require workspace or project predicate. I should be able to filter by them, but not be required to. I am limited to 100 objects already, why force me to filter unnecessarily? In the same vein - navigating the hierarchy of Asana seems an unnecessary tax for clients who are not Asana (and possibly even the Asana UI itself).
Any ideas or insights out there?
Have you ensured that the + you send is URL-encoded? Whatever library you are using should usually handle this (which language are you using, btw? We have some first-party client libraries available)
Try
&opt_fields=this.subtasks%2B.nameif you're creating the URL manually, or (better yet) use a library that correctly encodes URL query parameters.