Populate PostGIS geom column from GPX track data

Extract coordinates from parsed GPX tracks and store as PostGIS
LineString geometry via ST_GeomFromGeoJSON. Applied to:
- createRoute / updateRoute (routes.server.ts)
- createActivity / createRouteFromActivity (activities.server.ts)

Adds lineStringFromCoords() helper to the journal schema that
builds the SQL expression from [lon, lat] coordinate pairs.

Unblocks spatial queries (e.g. route discovery via ST_Intersects).

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

apps/journal/app/lib/activities.server.ts

@@ -1,8 +1,9 @@
 import { randomUUID } from "node:crypto";
 import { eq, desc } from "drizzle-orm";
 import { getDb } from "./db.ts";
-import { activities, routes } from "@trails-cool/db/schema/journal";
+import { activities, routes, lineStringFromCoords } from "@trails-cool/db/schema/journal";
 import { parseGpxAsync } from "@trails-cool/gpx";
+import type { SQL } from "drizzle-orm";
 
 export interface ActivityInput {
   name: string;
@@ -19,6 +20,7 @@ export async function createActivity(ownerId: string, input: ActivityInput) {
   let elevationGain: number | null = null;
   let elevationLoss: number | null = null;
   let startedAt: Date | null = null;
+  let geom: SQL | null = null;
 
   if (input.gpx) {
     try {
@@ -28,6 +30,9 @@ export async function createActivity(ownerId: string, input: ActivityInput) {
       elevationGain = gpxData.elevation.gain;
       elevationLoss = gpxData.elevation.loss;
 
+      const coords = gpxData.tracks.flat().map((p) => [p.lon, p.lat] as [number, number]);
+      if (coords.length >= 2) geom = lineStringFromCoords(coords);
+
       // Try to extract start time from first track point
       if (gpxData.tracks[0]?.[0]?.time) {
         startedAt = new Date(gpxData.tracks[0][0].time);
@@ -48,6 +53,7 @@ export async function createActivity(ownerId: string, input: ActivityInput) {
     elevationGain,
     elevationLoss,
     startedAt,
+    geom,
   });
 
   return id;
@@ -82,6 +88,17 @@ export async function createRouteFromActivity(activityId: string, ownerId: strin
   if (!activity?.gpx) return null;
 
   const routeId = randomUUID();
+  let routeGeom: SQL | null = null;
+  if (activity.gpx) {
+    try {
+      const gpxData = await parseGpxAsync(activity.gpx);
+      const coords = gpxData.tracks.flat().map((p) => [p.lon, p.lat] as [number, number]);
+      if (coords.length >= 2) routeGeom = lineStringFromCoords(coords);
+    } catch {
+      // Continue without geom
+    }
+  }
+
   await db.insert(routes).values({
     id: routeId,
     ownerId,
@@ -91,6 +108,7 @@ export async function createRouteFromActivity(activityId: string, ownerId: strin
     distance: activity.distance,
     elevationGain: activity.elevationGain,
     elevationLoss: activity.elevationLoss,
+    geom: routeGeom,
   });
 
   // Link the activity to the new route

apps/journal/app/lib/routes.server.ts

@@ -1,8 +1,9 @@
 import { randomUUID } from "node:crypto";
 import { eq, desc, and } from "drizzle-orm";
 import { getDb } from "./db.ts";
-import { routes, routeVersions } from "@trails-cool/db/schema/journal";
+import { routes, routeVersions, lineStringFromCoords } from "@trails-cool/db/schema/journal";
 import { parseGpx } from "@trails-cool/gpx";
+import type { SQL } from "drizzle-orm";
 
 export interface RouteInput {
   name: string;
@@ -18,12 +19,14 @@ export async function createRoute(ownerId: string, input: RouteInput) {
   let distance: number | null = null;
   let elevationGain: number | null = null;
   let elevationLoss: number | null = null;
+  let geom: SQL | null = null;
 
   if (input.gpx) {
     const stats = computeRouteStats(input.gpx);
     distance = stats.distance;
     elevationGain = stats.elevationGain;
     elevationLoss = stats.elevationLoss;
+    geom = stats.geom;
   }
 
   await db.insert(routes).values({
@@ -36,6 +39,7 @@ export async function createRoute(ownerId: string, input: RouteInput) {
     distance,
     elevationGain,
     elevationLoss,
+    geom,
   });
 
   // Create initial version if GPX provided
@@ -99,6 +103,7 @@ export async function updateRoute(
     updateData.distance = stats.distance;
     updateData.elevationGain = stats.elevationGain;
     updateData.elevationLoss = stats.elevationLoss;
+    updateData.geom = stats.geom;
 
     // Get next version number
     const existingVersions = await db
@@ -136,6 +141,7 @@ export async function deleteRoute(id: string, ownerId: string) {
 function computeRouteStats(gpxString: string) {
   try {
     const gpxData = parseGpx(gpxString);
+    const coords = gpxData.tracks.flat().map((p) => [p.lon, p.lat] as [number, number]);
     return {
       distance: Math.round(
         gpxData.elevation.profile.length > 0
@@ -144,8 +150,9 @@ function computeRouteStats(gpxString: string) {
       ),
       elevationGain: gpxData.elevation.gain,
       elevationLoss: gpxData.elevation.loss,
+      geom: coords.length >= 2 ? lineStringFromCoords(coords) : null,
     };
   } catch {
-    return { distance: null, elevationGain: null, elevationLoss: null };
+    return { distance: null, elevationGain: null, elevationLoss: null, geom: null };
   }
 }

packages/db/src/schema/journal.ts

@@ -7,6 +7,7 @@ import {
   jsonb,
   customType,
 } from "drizzle-orm/pg-core";
+import { sql, type SQL } from "drizzle-orm";
 
 const bytea = customType<{ data: Buffer }>({
   dataType() {
@@ -14,12 +15,27 @@ const bytea = customType<{ data: Buffer }>({
   },
 });
 
-const lineString = customType<{ data: string }>({
+const lineString = customType<{ data: string | SQL }>({
   dataType() {
     return "geometry(LineString, 4326)";
   },
+  toDriver(value) {
+    return value;
+  },
 });
 
+/**
+ * Build a SQL expression to create a PostGIS LineString from coordinate pairs.
+ * Coordinates are [lon, lat] (GeoJSON order).
+ */
+export function lineStringFromCoords(coords: [number, number][]): SQL {
+  const geojson = JSON.stringify({
+    type: "LineString",
+    coordinates: coords,
+  });
+  return sql`ST_GeomFromGeoJSON(${geojson})`;
+}
+
 export const journalSchema = pgSchema("journal");
 
 export const users = journalSchema.table("users", {