[WIP][ENG-3568] keen replacement

[aaxelb]

Purpose

store analytics data in our own elasticsearch index(es), to prepare for eventually dropping (some) third-party analytics

Changes

• move contents of osf/metrics.py into multiple files in osf/metrics/
• move daily reporting logic from scripts/analytics/ to osf/metrics/reporters/ -- save results in our own elasticsearch, in addition to sending to keen
• add CountedUsage metric to support usage reporting
• update legacy-frontend js to track pageview events using CountedUsage (in addition to sending to keen)
• new management commands:
  • daily_reporters_go to generate daily reports (also added to the admin's management-command page)
  • fake_metrics_reports to generate fake daily reports for local testing

new api routes:

• /_/metrics/events/counted_usage/: POST to record osf usage, e.g. pageviews
• /_/metrics/reports/: GET available report types
• /_/metrics/reports/<report_name>/latest/: GET latest report of the given type
• /_/metrics/reports/<report_name>/recent/: GET list of recent reports (up to 1000 with ?days_back=1000
• /_/metrics/query/node_analytics/<node_guid>/<timespan>: GET data necessary to support the existing node analytics page

QA Notes

Please make verification statements inspired by your code and what your code touches.

• Verify POSTing pageview info for a node page to /_/metrics/events/counted_usage/ responds 201 Created and increases viewcount in the node_analytics query
• Verify POSTing duplicate pageview info multiple times in the same 30-second window is counted as only one pageview
• Verify the latest report of each type has a report_date of yesterday
• Verify running daily_reporters_go multiple times for the same date does NOT result in duplicate reports

What are the areas of risk?

• losing data by mis-recording

Any concerns/considerations/questions that development raised?

Documentation

Side Effects

Ticket

ENG-3568