From c2a7a9bd6a29cd139e4404b394e75797b787de3e Mon Sep 17 00:00:00 2001
From: Paul Frazee <pfrazee@gmail.com>
Date: Wed, 21 Apr 2021 15:00:32 -0500
Subject: [PATCH] Admin UI: Apply unique constraint to login metric

---
 frontend/static/js/admin/dashboard.js |  9 ++++++---
 lib/metrics.js                        | 20 ++++++++++++++++++--
 2 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/frontend/static/js/admin/dashboard.js b/frontend/static/js/admin/dashboard.js
index de52cf82..736cf637 100644
--- a/frontend/static/js/admin/dashboard.js
+++ b/frontend/static/js/admin/dashboard.js
@@ -42,17 +42,20 @@ class Dashboard extends LitElement {
     this.requestUpdate()
     this.metrics.day = await session.api.server.countMultipleMetricsEvents({
       timespan: 'day',
-      events: ['signed-up', 'logged-in', 'community-created', 'post-created', 'comment-created']
+      events: ['signed-up', 'logged-in', 'community-created', 'post-created', 'comment-created'],
+      uniqueBys: {'logged-in': 'user'}
     })
     this.requestUpdate()
     this.metrics.week = await session.api.server.countMultipleMetricsEvents({
       timespan: 'week',
-      events: ['signed-up', 'logged-in', 'community-created', 'post-created', 'comment-created']
+      events: ['signed-up', 'logged-in', 'community-created', 'post-created', 'comment-created'],
+      uniqueBys: {'logged-in': 'user'}
     })
     this.requestUpdate()
     this.metrics.month = await session.api.server.countMultipleMetricsEvents({
       timespan: 'month',
-      events: ['signed-up', 'logged-in', 'community-created', 'post-created', 'comment-created']
+      events: ['signed-up', 'logged-in', 'community-created', 'post-created', 'comment-created'],
+      uniqueBys: {'logged-in': 'user'}
     })
     this.requestUpdate()
     this.httpHits = Object.entries(await session.api.server.aggregateHttpHits({timespan: 'day'}))
diff --git a/lib/metrics.js b/lib/metrics.js
index 6fe5708a..2ad1baf4 100644
--- a/lib/metrics.js
+++ b/lib/metrics.js
@@ -34,12 +34,17 @@ export function commentCreated ({user}) {
   return metricEventsLog.append({event: 'comment-created', user})
 }
 
-export async function listEvents ({event, timespan}) {
+export async function listEvents ({event, timespan, uniqueBy}) {
   const log = event === 'http-request' ? trafficLog : metricEventsLog
   let startTs = timespanToTS(timespan)
+  let hasSeen = uniqueBy ? new Set() : undefined
   return log.query(entry => {
     if (entry.ts < startTs) return false
     if (event && entry.event !== event) return false
+    if (uniqueBy) {
+      if (hasSeen.has(entry[uniqueBy])) return false
+      hasSeen.add(entry[uniqueBy])
+    }
     return true
   })
 }
@@ -48,16 +53,27 @@ export async function countEvents (opts) {
   return (await listEvents(opts))?.length || 0
 }
 
-export async function countMultipleEvents ({events, timespan}) {
+export async function countMultipleEvents ({events, timespan, uniqueBys}) {
   if (!events || !Array.isArray(events)) {
     throw new Error('Events must be an array of strings')
   }
   let startTs = timespanToTS(timespan)
   const counts = {}
   events.forEach(evt => counts[evt] = 0)
+  let hasSeens = undefined
+  if (uniqueBys) {
+    hasSeens = {}
+    for (let k in uniqueBys) {
+      hasSeens[k] = new Set()
+    }
+  }
   await metricEventsLog.query(entry => {
     if (entry.ts < startTs) return false
     if (!events.includes(entry.event)) return false
+    if (uniqueBys?.[entry.event]) {
+      if (hasSeens[entry.event].has(entry[uniqueBys[entry.event]])) return false
+      hasSeens[entry.event].add(entry[uniqueBys[entry.event]])
+    }
     counts[entry.event]++
     return false
   })