July 2018
Intermediate to advanced
574 pages
14h 7m
English
In the previous section, we ended up getting the number of files per user. We will now iterate on the previous result to create a disk-usage ranking. Since we want the disk usage, we will have to update the previous files_by_user_v3 flow so that it accumulates each file size per user id as well:
$ cat examples/search.exsimport_file("./examples/sample_data.exs")# ...disk_usage_by_user = media_set |> Flow.from_enumerable(max_demand: 1) |> Flow.partition(key: {:key, :user_id}) |> Flow.reduce(fn -> %{} end, fn %{user_id: user_id, file_size: size}, accum -> Map.update(accum, user_id, size, &(&1 + size)) end)
The previous disk_usage_by_user flow gives us the expected results, showing each user's disk usage. User 3 is clearly ...