feat(metrics): cached project metrics recomputed on ingest

scripts/setup-remote.ts

@@ -140,6 +140,24 @@ async function ensureProjectIngestFields(pb: PocketBase): Promise<void> {
   const additions = [
     { name: "webhook_secret", type: "text", required: false, max: 80 },
     { name: "last_ingest_at", type: "date", required: false },
+    {
+      name: "session_gap_minutes",
+      type: "number",
+      required: false,
+      onlyInt: true,
+    },
+    {
+      name: "pre_session_minutes",
+      type: "number",
+      required: false,
+      onlyInt: true,
+    },
+    {
+      name: "post_session_minutes",
+      type: "number",
+      required: false,
+      onlyInt: true,
+    },
   ];
 
   const fields = [...(projects.fields as unknown[])];
@@ -712,6 +730,44 @@ async function main(): Promise<void> {
     deleteRule: null,
   });
 
+  // 10. project_metrics — a computed cache, rebuilt on ingest. The dashboard
+  // reads this rather than aggregating hundreds of commit rows per page view.
+  await getOrCreateCollection(pb, {
+    name: "project_metrics",
+    type: "base",
+    listRule: AUTHED,
+    viewRule: AUTHED,
+    createRule: null,
+    updateRule: null,
+    deleteRule: null,
+    fields: [
+      {
+        name: "project",
+        type: "relation",
+        required: true,
+        collectionId: (await pb.collections.getOne("projects")).id,
+        cascadeDelete: true,
+        minSelect: 0,
+        maxSelect: 1,
+      },
+      { name: "computed_at", type: "date", required: true },
+      { name: "payload", type: "json", required: true, maxSize: 4_000_000 },
+      { name: "created", type: "autodate", onCreate: true, onUpdate: false },
+      { name: "updated", type: "autodate", onCreate: true, onUpdate: true },
+    ],
+    indexes: [
+      "CREATE UNIQUE INDEX idx_metrics_project ON project_metrics (project)",
+    ],
+  });
+
+  await applyRules(pb, "project_metrics", {
+    listRule: scopedRead("project.client"),
+    viewRule: scopedRead("project.client"),
+    createRule: null,
+    updateRule: null,
+    deleteRule: null,
+  });
+
   // Add ingest-related fields to projects (only if missing — the projects
   // collection already exists from earlier migrations).
   await ensureProjectIngestFields(pb);

src/app/actions/metrics.ts

@@ -0,0 +1,27 @@
+"use server";
+
+import { revalidatePath } from "next/cache";
+
+import { requireSession } from "@/lib/auth/session";
+import { recomputeMetrics } from "@/lib/metrics/store";
+
+/**
+ * Recompute on demand.
+ *
+ * Needed because the constants can change without any commit arriving, and
+ * because a client asking about a stale figure should be answerable in one
+ * click rather than by waiting for the next push.
+ */
+export async function recomputeMetricsAction(input: {
+  projectId: string;
+  clientSlug: string;
+  projectSlug: string;
+}): Promise<{ commits: number }> {
+  const session = await requireSession();
+  if (session.role !== "owner") throw new Error("Not found");
+
+  const metrics = await recomputeMetrics(input.projectId);
+
+  revalidatePath(`/p/${input.clientSlug}/${input.projectSlug}/dashboard`);
+  return { commits: metrics.totalCommits };
+}

src/lib/git/ingest.ts

@@ -174,6 +174,10 @@ export async function ingestProject(
   const { relinkProject } = await import("@/lib/linking/engine");
   await relinkProject(project.id);
 
+  // And the dashboard figures must follow.
+  const { recomputeMetrics } = await import("@/lib/metrics/store");
+  await recomputeMetrics(project.id);
+
   return { created, skipped, pagesRead: page };
 }
 

src/lib/metrics/store.ts

@@ -0,0 +1,76 @@
+import "server-only";
+
+import { getAdminPb } from "@/lib/pb/admin";
+import { computeProjectMetrics, type ProjectMetrics } from "@/lib/metrics/compute";
+import {
+  DEFAULT_SESSION_CONSTANTS,
+  type SessionConstants,
+} from "@/lib/metrics/sessions";
+import type { CommitRecord, ProjectMetricsRecord, ProjectRecord } from "@/lib/pb/types";
+
+/**
+ * A project's tuning constants, falling back to the defaults.
+ *
+ * Zero and undefined both mean "not set". A project must never compute with a
+ * gap of zero minutes — every commit would become its own session and the
+ * estimate would be padding multiplied by commit count.
+ */
+export function constantsFor(project: Partial<ProjectRecord>): SessionConstants {
+  return {
+    sessionGapMinutes:
+      project.session_gap_minutes || DEFAULT_SESSION_CONSTANTS.sessionGapMinutes,
+    preSessionMinutes:
+      project.pre_session_minutes || DEFAULT_SESSION_CONSTANTS.preSessionMinutes,
+    postSessionMinutes:
+      project.post_session_minutes || DEFAULT_SESSION_CONSTANTS.postSessionMinutes,
+  };
+}
+
+/**
+ * Recompute and cache a project's metrics.
+ *
+ * The constants used are stored inside the payload by computeProjectMetrics, so
+ * a figure the client is looking at can always be explained by the settings
+ * that produced it rather than by whatever they are when someone later asks.
+ */
+export async function recomputeMetrics(projectId: string): Promise<ProjectMetrics> {
+  const pb = await getAdminPb();
+
+  const project = await pb
+    .collection("projects")
+    .getOne<ProjectRecord>(projectId);
+
+  const commits = await pb.collection("commits").getFullList<CommitRecord>({
+    filter: `project = "${projectId}"`,
+    fields: "type,scope,authored_at,is_merge",
+  });
+
+  const metrics = computeProjectMetrics(
+    commits.map((c) => ({
+      type: c.type ?? "other",
+      scope: c.scope ?? "",
+      authoredAt: c.authored_at,
+      isMerge: Boolean(c.is_merge),
+    })),
+    constantsFor(project)
+  );
+
+  const payload = {
+    project: projectId,
+    computed_at: new Date().toISOString(),
+    payload: metrics,
+  };
+
+  const existing = await pb
+    .collection("project_metrics")
+    .getFirstListItem<ProjectMetricsRecord>(`project = "${projectId}"`)
+    .catch(() => null);
+
+  if (existing) {
+    await pb.collection("project_metrics").update(existing.id, payload);
+  } else {
+    await pb.collection("project_metrics").create(payload);
+  }
+
+  return metrics;
+}

src/lib/pb/types.ts

@@ -52,6 +52,9 @@ export interface ProjectRecord extends BaseRecord {
   /** Server-only. Must never appear in a browser payload. */
   webhook_secret: string;
   last_ingest_at: string;
+  session_gap_minutes: number;
+  pre_session_minutes: number;
+  post_session_minutes: number;
 }
 
 export interface ColumnRecord extends BaseRecord {
@@ -96,6 +99,13 @@ export interface CommentRecord extends BaseRecord {
 
 export type CommitLinkSource = "explicit" | "scope" | "manual" | "none";
 
+export interface ProjectMetricsRecord extends BaseRecord {
+  project: string;
+  computed_at: string;
+  /** A serialised ProjectMetrics from @/lib/metrics/compute. */
+  payload: unknown;
+}
+
 export interface CommitRecord extends BaseRecord {
   project: string;
   sha: string;