feat: summarise /activity by period with per-repo change counts

The bare /activity route (no timespan modifier) now shows one timeline
card per period — each listing the repos touched and the number of
changes in each — with a daily/weekly/monthly/yearly bucket selector,
so the view answers "where did my time go" at a glance. Each card
drills down to the existing per-event view via /activity/from..to,
which is unchanged.

Backed by a new GET /v1/activity/summary?from&to&bucket&source
endpoint: public events only (private repo names never leak), bucketed
with date_trunc on the UTC-shifted timestamp, reusing the same
per-source repo extraction as /v1/projects. Blog events carry no repo
and are excluded.

The /activity prerender now bakes the daily summary instead of the
event list. On the first deploy the live API won't have the endpoint
yet when build-web prerenders; that route degrades to the client-side
fallback and self-heals on the daily refresh re-bake.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01LY4nbfHC9qt726gVrdAh3X

crates/moments-api/src/main.rs

@@ -13,7 +13,8 @@ use moments_core::{EventReader, reshape};
 use moments_data::PgStore;
 use moments_entities::{
     BlogPost, BlogPostSummary, DailyCount, Event, EventQuery, HourlyAvg, LanguageDailyCount,
-    ProjectSummary, RepoLanguage, Source, SourceSummary, TimelineItem,
+    ProjectSummary, RepoLanguage, RepoPeriodCount, Source, SourceSummary, SummaryBucket,
+    TimelineItem,
 };
 use serde::Deserialize;
 use tower_http::{cors::CorsLayer, trace::TraceLayer};
@@ -62,6 +63,7 @@ async fn main() -> anyhow::Result<()> {
         .route("/v1/blog", get(list_blog_posts))
         .route("/v1/blog/{slug}", get(get_blog_post))
         .route("/v1/activity/daily", get(daily_counts))
+        .route("/v1/activity/summary", get(activity_summary))
         .route("/v1/activity/hourly", get(hourly_avgs))
         .route("/v1/languages/daily", get(language_daily_counts))
         .route("/v1/languages/repos", get(repo_languages))
@@ -224,6 +226,47 @@ async fn daily_counts(
     Ok(Json(counts))
 }
 
+#[derive(Debug, Deserialize)]
+struct SummaryParams {
+    from: Option<NaiveDate>,
+    to: Option<NaiveDate>,
+    /// Bucket granularity: day (default), week, month or year.
+    bucket: Option<String>,
+    /// Comma-separated list, e.g. `source=github,gitea`.
+    source: Option<String>,
+}
+
+/// Per-repo event counts bucketed into periods, for the timeline summary
+/// view. Public events only — repo names of private activity never leak.
+async fn activity_summary(
+    State(state): State<AppState>,
+    Query(params): Query<SummaryParams>,
+) -> Result<Json<Vec<RepoPeriodCount>>, ApiError> {
+    let to = params.to.unwrap_or_else(|| Utc::now().date_naive());
+    let from = params
+        .from
+        .unwrap_or_else(|| to - chrono::Duration::days(365));
+    let bucket = params
+        .bucket
+        .as_deref()
+        .unwrap_or("day")
+        .parse::<SummaryBucket>()
+        .map_err(|e| ApiError::bad_request(e.to_string()))?;
+    let sources = params.source.as_deref().map(parse_sources).transpose()?;
+    let counts = state
+        .store
+        .activity_summary(
+            from,
+            to,
+            bucket,
+            sources.as_deref(),
+            /* include_private */ false,
+        )
+        .await
+        .map_err(internal)?;
+    Ok(Json(counts))
+}
+
 async fn language_daily_counts(
     State(state): State<AppState>,
     Query(params): Query<DailyCountsParams>,

crates/moments-core/src/lib.rs

@@ -8,7 +8,7 @@ use async_trait::async_trait;
 use chrono::NaiveDate;
 use moments_entities::{
     DailyCount, Event, EventQuery, HourlyAvg, LanguageDailyCount, ProjectSummary, RepoLanguage,
-    SourceSummary,
+    RepoPeriodCount, Source, SourceSummary, SummaryBucket,
 };
 
 #[derive(Debug, thiserror::Error)]
@@ -38,6 +38,15 @@ pub trait EventReader: Send + Sync {
         to: NaiveDate,
         include_private: bool,
     ) -> Result<Vec<LanguageDailyCount>, StoreError>;
+    /// Per-repo event counts bucketed into day/week/month/year periods.
+    async fn activity_summary(
+        &self,
+        from: NaiveDate,
+        to: NaiveDate,
+        bucket: SummaryBucket,
+        sources: Option<&[Source]>,
+        include_private: bool,
+    ) -> Result<Vec<RepoPeriodCount>, StoreError>;
     async fn hourly_avgs(
         &self,
         from: NaiveDate,

crates/moments-data/src/lib.rs

@@ -12,7 +12,7 @@ use chrono::{DateTime, Utc};
 use moments_core::{EventReader, EventWriter, PollerState, PollerStateStore, StoreError};
 use moments_entities::{
     DailyCount, Event, EventQuery, HourlyAvg, LanguageDailyCount, ProjectSummary, RepoLanguage,
-    Source, SourceSummary,
+    RepoPeriodCount, Source, SourceSummary, SummaryBucket,
 };
 use sqlx::Row;
 use sqlx::postgres::{PgPool, PgPoolOptions};
@@ -317,6 +317,73 @@ impl EventReader for PgStore {
             .collect()
     }
 
+    async fn activity_summary(
+        &self,
+        from: NaiveDate,
+        to: NaiveDate,
+        bucket: SummaryBucket,
+        sources: Option<&[Source]>,
+        include_private: bool,
+    ) -> Result<Vec<RepoPeriodCount>, StoreError> {
+        let sources: Option<Vec<String>> =
+            sources.map(|s| s.iter().map(|x| x.as_str().to_string()).collect());
+
+        // `bucket.as_str()` is one of day/week/month/year, bound as the
+        // date_trunc field. Truncation happens on the UTC-shifted timestamp so
+        // period boundaries match the UTC day-stamping used everywhere else.
+        let rows = sqlx::query(
+            r#"
+            SELECT date_trunc($3, occurred_at AT TIME ZONE 'UTC')::date AS period,
+                   source, repo, COUNT(*)::bigint AS count
+            FROM (
+                SELECT source, occurred_at,
+                    CASE source
+                        WHEN 'github' THEN COALESCE(
+                            payload->'repo'->>'name',
+                            payload->'repository'->>'full_name',
+                            payload->>'_repo'
+                        )
+                        WHEN 'gitea' THEN COALESCE(
+                            payload->'repo'->>'full_name',
+                            payload->'repo'->>'name'
+                        )
+                        WHEN 'hg'       THEN payload->>'_repo'
+                        WHEN 'bugzilla' THEN payload->>'product'
+                        ELSE NULL
+                    END AS repo
+                FROM events
+                WHERE occurred_at >= ($1::date::timestamp AT TIME ZONE 'UTC')
+                  AND occurred_at <  (($2::date + 1)::timestamp AT TIME ZONE 'UTC')
+                  AND ($4::text[] IS NULL OR source = ANY($4))
+                  AND ($5::bool OR public = true)
+            ) sub
+            WHERE repo IS NOT NULL AND repo != ''
+            GROUP BY period, source, repo
+            ORDER BY period DESC, count DESC, repo
+            "#,
+        )
+        .bind(from)
+        .bind(to)
+        .bind(bucket.as_str())
+        .bind(sources.as_deref())
+        .bind(include_private)
+        .fetch_all(&self.pool)
+        .await
+        .map_err(map_err)?;
+
+        rows.into_iter()
+            .map(|r| {
+                let source_str: String = r.try_get("source").map_err(map_err)?;
+                Ok(RepoPeriodCount {
+                    period: r.try_get("period").map_err(map_err)?,
+                    source: Source::from_str(&source_str).map_err(map_err)?,
+                    repo: r.try_get("repo").map_err(map_err)?,
+                    count: r.try_get("count").map_err(map_err)?,
+                })
+            })
+            .collect()
+    }
+
     async fn hourly_avgs(
         &self,
         from: NaiveDate,

crates/moments-entities/src/lib.rs

@@ -95,6 +95,56 @@ pub struct DailyCount {
     pub count: i64,
 }
 
+/// Bucketing granularity for `GET /v1/activity/summary`.
+#[derive(Debug, Clone, Copy, Serialize, Deserialize, PartialEq, Eq)]
+#[serde(rename_all = "lowercase")]
+pub enum SummaryBucket {
+    Day,
+    Week,
+    Month,
+    Year,
+}
+
+impl SummaryBucket {
+    /// Postgres `date_trunc` field name.
+    pub fn as_str(&self) -> &'static str {
+        match self {
+            SummaryBucket::Day => "day",
+            SummaryBucket::Week => "week",
+            SummaryBucket::Month => "month",
+            SummaryBucket::Year => "year",
+        }
+    }
+}
+
+impl std::str::FromStr for SummaryBucket {
+    type Err = ParseBucketError;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        match s {
+            "day" => Ok(SummaryBucket::Day),
+            "week" => Ok(SummaryBucket::Week),
+            "month" => Ok(SummaryBucket::Month),
+            "year" => Ok(SummaryBucket::Year),
+            other => Err(ParseBucketError(other.to_string())),
+        }
+    }
+}
+
+#[derive(Debug, thiserror::Error)]
+#[error("unknown bucket: {0} (expected day, week, month or year)")]
+pub struct ParseBucketError(pub String);
+
+/// Per-repo event count within one summary period. `period` is the UTC
+/// start date of the bucket (day, ISO week Monday, first of month/year).
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct RepoPeriodCount {
+    pub period: chrono::NaiveDate,
+    pub source: Source,
+    pub repo: String,
+    pub count: i64,
+}
+
 /// Average events per day at a given hour of the day, computed in a
 /// caller-supplied IANA timezone. 24 entries (0..=23).
 #[derive(Debug, Clone, Serialize, Deserialize)]

ui/src/api/client.ts

@@ -71,6 +71,16 @@ export interface DailyCount {
   count: number;
 }
 
+export type SummaryBucket = 'day' | 'week' | 'month' | 'year';
+
+export interface RepoPeriodCount {
+  /** UTC start date of the bucket (day, ISO week Monday, first of month/year). */
+  period: string;
+  source: Source;
+  repo: string;
+  count: number;
+}
+
 export interface HourlyAvg {
   hour: number;
   avg: number;
@@ -129,6 +139,19 @@ export async function fetchDailyCounts(from: string, to: string): Promise<DailyC
   return resp.json();
 }
 
+export async function fetchActivitySummary(
+  from: string,
+  to: string,
+  bucket: SummaryBucket,
+  sources?: Source[],
+): Promise<RepoPeriodCount[]> {
+  const params = new URLSearchParams({ from, to, bucket });
+  if (sources && sources.length > 0) params.set('source', sources.join(','));
+  const resp = await fetch(`${API_BASE}/activity/summary?${params}`);
+  if (!resp.ok) throw new Error(`activity-summary: HTTP ${resp.status}`);
+  return resp.json();
+}
+
 export async function fetchHourlyAvgs(from: string, to: string, tz: string): Promise<HourlyAvg[]> {
   const qs = new URLSearchParams({ from, to, tz });
   const resp = await fetch(`${API_BASE}/activity/hourly?${qs}`);

ui/src/components/Filters.tsx

@@ -16,6 +16,8 @@ interface Props {
   limit: number;
   onLimitChange: (n: number) => void;
   summaries: SourceSummary[] | undefined;
+  /** Hide the activity-count slider (summary mode has no event cap). */
+  showLimit?: boolean;
 }
 
 export function Filters({
@@ -28,6 +30,7 @@ export function Filters({
   limit,
   onLimitChange,
   summaries,
+  showLimit = true,
 }: Props) {
   const summaryFor = (src: Source) => summaries?.find((s) => s.source === src);
 
@@ -51,6 +54,7 @@ export function Filters({
             );
           })}
         </Col>
+        {showLimit && (
           <Col md={6}>
             <label style={{ fontSize: '70%' }}>
               number of activities to display: {limit}
@@ -62,6 +66,7 @@ export function Filters({
               onChange={(v) => onLimitChange(Array.isArray(v) ? v[0] : v)}
             />
           </Col>
+        )}
       </Row>
       <Row className="mb-3">
         <Col>

ui/src/components/SummaryEntry.tsx

@@ -0,0 +1,106 @@
+import { Link } from 'react-router-dom';
+import { Calendar3 } from 'react-bootstrap-icons';
+import { VerticalTimelineElement } from 'react-vertical-timeline-component';
+import type { RepoPeriodCount, SummaryBucket } from '../api/client';
+import { fmtDate } from '../lib/ranges';
+
+interface Props {
+  /** UTC start date of the period (YYYY-MM-DD). */
+  period: string;
+  bucket: SummaryBucket;
+  /** Rows for this period, already sorted by count descending. */
+  repos: RepoPeriodCount[];
+}
+
+/** One timeline card summarising a period: each repo touched and how many
+ *  changes landed in it, with a drill-down link to the per-event view. */
+export function SummaryEntry({ period, bucket, repos }: Props) {
+  const total = repos.reduce((sum, r) => sum + r.count, 0);
+  const end = periodEnd(period, bucket);
+  const timespan = bucket === 'day' ? period : `${period}..${end}`;
+
+  return (
+    <VerticalTimelineElement
+      date={periodLabel(period, bucket)}
+      iconStyle={{ background: '#546e7a', color: '#fff' }}
+      icon={<Calendar3 />}
+    >
+      <h4 className="vertical-timeline-element-title">
+        {total} {total === 1 ? 'change' : 'changes'} in {repos.length}{' '}
+        {repos.length === 1 ? 'repository' : 'repositories'}
+      </h4>
+      <ul style={{ listStyle: 'none', paddingLeft: 0, marginBottom: '0.5rem' }}>
+        {repos.map((r) => (
+          <li
+            key={`${r.source}:${r.repo}`}
+            className="d-flex justify-content-between"
+          >
+            <span>
+              <Link to={`/project/${r.source}/${r.repo}`}>{r.repo}</Link>{' '}
+              <small className="text-muted">{r.source}</small>
+            </span>
+            <span>{r.count}</span>
+          </li>
+        ))}
+      </ul>
+      <Link to={`/activity/${timespan}`} style={{ fontSize: '85%' }}>
+        view activity →
+      </Link>
+    </VerticalTimelineElement>
+  );
+}
+
+/** Last day of the period (YYYY-MM-DD), for the drill-down timespan. */
+function periodEnd(period: string, bucket: SummaryBucket): string {
+  const d = new Date(period + 'T00:00:00Z');
+  switch (bucket) {
+    case 'day':
+      return period;
+    case 'week':
+      d.setUTCDate(d.getUTCDate() + 6);
+      return fmtDate(d);
+    case 'month':
+      d.setUTCMonth(d.getUTCMonth() + 1);
+      d.setUTCDate(0);
+      return fmtDate(d);
+    case 'year':
+      return `${d.getUTCFullYear()}-12-31`;
+  }
+}
+
+/** Human label for the card's date gutter. Formatted in UTC so the
+ *  prerendered (Node) and client renders match byte-for-byte. */
+function periodLabel(period: string, bucket: SummaryBucket): string {
+  const d = new Date(period + 'T00:00:00Z');
+  switch (bucket) {
+    case 'day':
+      return d
+        .toLocaleDateString('en-GB', {
+          weekday: 'long',
+          year: 'numeric',
+          month: 'long',
+          day: 'numeric',
+          timeZone: 'UTC',
+        })
+        .toLowerCase();
+    case 'week':
+      return `week of ${d
+        .toLocaleDateString('en-GB', {
+          year: 'numeric',
+          month: 'long',
+          day: 'numeric',
+          timeZone: 'UTC',
+        })
+        .toLowerCase()}`;
+    case 'month':
+      return d
+        .toLocaleDateString('en-GB', {
+          year: 'numeric',
+          month: 'long',
+          timeZone: 'UTC',
+        })
+        .toLowerCase();
+    case 'year':
+      return String(d.getUTCFullYear());
+  }
+}

ui/src/pages/TimelineHome.tsx

@@ -1,18 +1,36 @@
-import { useMemo, useState } from 'react';
+import { useEffect, useMemo, useState } from 'react';
 import { useParams } from 'react-router-dom';
 import { useQuery } from '@tanstack/react-query';
+import Button from 'react-bootstrap/Button';
+import ButtonGroup from 'react-bootstrap/ButtonGroup';
 import Col from 'react-bootstrap/Col';
 import Row from 'react-bootstrap/Row';
 import { VerticalTimeline } from 'react-vertical-timeline-component';
 
-import { fetchDailyCounts, fetchEvents, fetchSources, type Source } from '../api/client';
+import {
+  fetchActivitySummary,
+  fetchDailyCounts,
+  fetchEvents,
+  fetchSources,
+  type RepoPeriodCount,
+  type Source,
+  type SummaryBucket,
+} from '../api/client';
 import { Filters } from '../components/Filters';
+import { SummaryEntry } from '../components/SummaryEntry';
 import { TimelineEntry } from '../components/TimelineEntry';
 import { defaultActivityRange, endOfTodayMs, fmtDate } from '../lib/ranges';
 
 const RANGE_MIN = new Date('2010-01-01T00:00:00Z').getTime();
 const RANGE_MAX = endOfTodayMs();
 
+const BUCKETS: { value: SummaryBucket; label: string }[] = [
+  { value: 'day', label: 'daily' },
+  { value: 'week', label: 'weekly' },
+  { value: 'month', label: 'monthly' },
+  { value: 'year', label: 'yearly' },
+];
+
 function parseDate(s: string): number {
   // Accept YYYY-MM-DD or full ISO datetime
   const t = new Date(s.includes('T') ? s : s + 'T00:00:00Z').getTime();
@@ -41,6 +59,9 @@ function parseTimespan(timespan?: string): [number, number] | null {
 
 export function TimelineHome() {
   const { timespan } = useParams();
+  // Without a date modifier in the route, show per-period summaries instead
+  // of individual events; drill-down links navigate to /activity/:timespan.
+  const summaryMode = !parseTimespan(timespan);
 
   const [enabledSources, setEnabledSources] = useState<Record<Source, boolean>>({
     github: true,
@@ -56,6 +77,15 @@ export function TimelineHome() {
     return [from, to];
   });
   const [limit, setLimit] = useState<number>(100);
+  const [bucket, setBucket] = useState<SummaryBucket>('day');
+
+  // The summary and event views are the same component at the same route
+  // position, so React keeps state across navigation between them. Sync the
+  // slider to the route's timespan (e.g. a summary card's drill-down link).
+  useEffect(() => {
+    const parsed = parseTimespan(timespan);
+    if (parsed) setRangeValue(parsed);
+  }, [timespan]);
 
   const sourcesQ = useQuery({
     queryKey: ['sources'],
@@ -84,14 +114,35 @@ export function TimelineHome() {
         limit,
       }),
     refetchInterval: 60_000,
+    enabled: !summaryMode,
   });
 
   const events = eventsQ.data ?? [];
 
+  const summaryQ = useQuery({
+    queryKey: ['activity-summary', fromStr, toStr, bucket, activeSources],
+    queryFn: () => fetchActivitySummary(fromStr, toStr, bucket, activeSources),
+    refetchInterval: 60_000,
+    enabled: summaryMode,
+  });
+
+  // Group the flat rows into periods. The API orders by period desc then
+  // count desc, so Map insertion order is already the display order.
+  const periods = useMemo(() => {
+    const byPeriod = new Map<string, RepoPeriodCount[]>();
+    for (const row of summaryQ.data ?? []) {
+      const list = byPeriod.get(row.period);
+      if (list) list.push(row);
+      else byPeriod.set(row.period, [row]);
+    }
+    return [...byPeriod.entries()];
+  }, [summaryQ.data]);
+
   const dailyQ = useQuery({
     queryKey: ['daily-counts', fromStr, toStr],
     queryFn: () => fetchDailyCounts(fromStr, toStr),
     staleTime: 5 * 60_000,
+    enabled: !summaryMode,
   });
   const totalCount = useMemo(
     () => (dailyQ.data ?? []).reduce((sum, d) => sum + d.count, 0),
@@ -99,6 +150,8 @@ export function TimelineHome() {
   );
   const privateCount = totalCount - events.length;
 
+  const statusQ = summaryMode ? summaryQ : eventsQ;
+
   return (
     <>
       <Filters
@@ -113,19 +166,49 @@ export function TimelineHome() {
         limit={limit}
         onLimitChange={setLimit}
         summaries={sourcesQ.data}
+        showLimit={!summaryMode}
       />
 
+      {summaryMode && (
+        <Row className="mb-3">
+          <Col className="text-center">
+            <ButtonGroup size="sm">
+              {BUCKETS.map((b) => (
+                <Button
+                  key={b.value}
+                  variant={bucket === b.value ? 'secondary' : 'outline-secondary'}
+                  onClick={() => setBucket(b.value)}
+                >
+                  {b.label}
+                </Button>
+              ))}
+            </ButtonGroup>
+          </Col>
+        </Row>
+      )}
+
       <Row>
         <Col>
           <p className="text-center" style={{ fontSize: '85%' }}>
-            {eventsQ.isLoading
+            {statusQ.isLoading
               ? 'loading…'
-              : eventsQ.isError
-                ? `error: ${(eventsQ.error as Error).message}`
+              : statusQ.isError
+                ? `error: ${(statusQ.error as Error).message}`
+                : summaryMode
+                  ? `showing ${periods.length} ${BUCKETS.find((b) => b.value === bucket)?.label} ${periods.length === 1 ? 'summary' : 'summaries'}`
                   : `showing ${events.length} public ${events.length === 1 ? 'activity' : 'activities'}${privateCount > 0 ? `, ${privateCount} private` : ''}`}
           </p>
           <VerticalTimeline>
-            {events.map((item) => (
+            {summaryMode
+              ? periods.map(([period, repos]) => (
+                  <SummaryEntry
+                    key={period}
+                    period={period}
+                    bucket={bucket}
+                    repos={repos}
+                  />
+                ))
+              : events.map((item) => (
                   <TimelineEntry key={item.id} item={item} />
                 ))}
           </VerticalTimeline>

ui/src/prerender/prefetch.ts

@@ -8,6 +8,7 @@
 import type { QueryClient } from '@tanstack/react-query';
 
 import {
+  fetchActivitySummary,
   fetchBlogPost,
   fetchBlogPosts,
   fetchDailyCounts,
@@ -34,7 +35,6 @@ import {
 // Sources the timeline shows by default, in the same insertion order as
 // TimelineHome's `enabledSources` (the array order is part of the query key).
 const ALL_SOURCES: Source[] = ['github', 'gitea', 'hg', 'bugzilla', 'blog'];
-const TIMELINE_LIMIT = 100;
 const PROJECT_EVENT_LIMIT = 500;
 
 async function prefetchDash(qc: QueryClient): Promise<void> {
@@ -72,25 +72,17 @@ async function prefetchDash(qc: QueryClient): Promise<void> {
 }
 
 async function prefetchActivity(qc: QueryClient): Promise<void> {
-  // Only the default `/activity` view is prerendered. Timespan-parameterised
-  // routes (`/activity/:timespan`) are unbounded, so they SPA-fall-back to the
+  // Only the default `/activity` view is prerendered — the per-period summary
+  // with the default daily bucket. Timespan-parameterised routes
+  // (`/activity/:timespan`) are unbounded, so they SPA-fall-back to the
   // client and refetch.
   const range = defaultActivityRange();
   await Promise.all([
     qc.prefetchQuery({ queryKey: ['sources'], queryFn: fetchSources }),
     qc.prefetchQuery({
-      queryKey: ['events', range.fromStr, range.toStr, ALL_SOURCES, TIMELINE_LIMIT],
+      queryKey: ['activity-summary', range.fromStr, range.toStr, 'day', ALL_SOURCES],
       queryFn: () =>
-        fetchEvents({
-          from: new Date(range.from),
-          to: new Date(range.to),
-          sources: ALL_SOURCES,
-          limit: TIMELINE_LIMIT,
-        }),
-    }),
-    qc.prefetchQuery({
-      queryKey: ['daily-counts', range.fromStr, range.toStr],
-      queryFn: () => fetchDailyCounts(range.fromStr, range.toStr),
+        fetchActivitySummary(range.fromStr, range.toStr, 'day', ALL_SOURCES),
     }),
   ]);
 }