Migrate geo backend from Django/Graphene to Express + Apollo Server + arangojs

Replace Python stack with TypeScript. All 30+ GraphQL queries preserved including
phase-based routing (Dijkstra), H3 clustering, K_SHORTEST_PATHS, and external
routing services (GraphHopper, OpenRailRouting). Single public endpoint, no auth.

src/cluster.ts

@@ -0,0 +1,192 @@
+import { latLngToCell, cellToLatLng } from 'h3-js'
+import { getDb } from './db.js'
+
+const ZOOM_TO_RES: Record<number, number> = {
+  0: 0, 1: 0, 2: 1, 3: 1, 4: 2, 5: 2,
+  6: 3, 7: 3, 8: 4, 9: 4, 10: 5, 11: 5,
+  12: 6, 13: 7, 14: 8, 15: 9, 16: 10,
+}
+
+interface CachedNode {
+  _key: string
+  name?: string
+  latitude?: number
+  longitude?: number
+  country?: string
+  country_code?: string
+  node_type?: string
+  transport_types?: string[]
+}
+
+const nodesCache = new Map<string, CachedNode[]>()
+
+function fetchNodes(transportType?: string | null, nodeType?: string | null): CachedNode[] {
+  const cacheKey = `nodes:${transportType || 'all'}:${nodeType || 'logistics'}`
+  if (nodesCache.has(cacheKey)) return nodesCache.get(cacheKey)!
+
+  const db = getDb()
+  let aql: string
+
+  if (nodeType === 'offer') {
+    aql = `
+      FOR node IN nodes
+        FILTER node.node_type == 'offer'
+        FILTER node.latitude != null AND node.longitude != null
+        RETURN node
+    `
+  } else if (nodeType === 'supplier') {
+    aql = `
+      FOR offer IN nodes
+        FILTER offer.node_type == 'offer'
+        FILTER offer.supplier_uuid != null
+        LET supplier = DOCUMENT(CONCAT('nodes/', offer.supplier_uuid))
+        FILTER supplier != null
+        FILTER supplier.latitude != null AND supplier.longitude != null
+        COLLECT sup_uuid = offer.supplier_uuid INTO offers
+        LET sup = DOCUMENT(CONCAT('nodes/', sup_uuid))
+        RETURN {
+          _key: sup_uuid,
+          name: sup.name,
+          latitude: sup.latitude,
+          longitude: sup.longitude,
+          country: sup.country,
+          country_code: sup.country_code,
+          node_type: 'supplier',
+          offers_count: LENGTH(offers)
+        }
+    `
+  } else {
+    aql = `
+      FOR node IN nodes
+        FILTER node.node_type == 'logistics' OR node.node_type == null
+        FILTER node.latitude != null AND node.longitude != null
+        RETURN node
+    `
+  }
+
+  // arangojs query returns a cursor — we need async. Use a sync cache pattern with pre-fetching.
+  // Since this is called from resolvers which are async, we'll use a different approach.
+  // Store a promise instead.
+  throw new Error('Use fetchNodesAsync instead')
+}
+
+export async function fetchNodesAsync(transportType?: string | null, nodeType?: string | null): Promise<CachedNode[]> {
+  const cacheKey = `nodes:${transportType || 'all'}:${nodeType || 'logistics'}`
+  if (nodesCache.has(cacheKey)) return nodesCache.get(cacheKey)!
+
+  const db = getDb()
+  let aql: string
+
+  if (nodeType === 'offer') {
+    aql = `
+      FOR node IN nodes
+        FILTER node.node_type == 'offer'
+        FILTER node.latitude != null AND node.longitude != null
+        RETURN node
+    `
+  } else if (nodeType === 'supplier') {
+    aql = `
+      FOR offer IN nodes
+        FILTER offer.node_type == 'offer'
+        FILTER offer.supplier_uuid != null
+        LET supplier = DOCUMENT(CONCAT('nodes/', offer.supplier_uuid))
+        FILTER supplier != null
+        FILTER supplier.latitude != null AND supplier.longitude != null
+        COLLECT sup_uuid = offer.supplier_uuid INTO offers
+        LET sup = DOCUMENT(CONCAT('nodes/', sup_uuid))
+        RETURN {
+          _key: sup_uuid,
+          name: sup.name,
+          latitude: sup.latitude,
+          longitude: sup.longitude,
+          country: sup.country,
+          country_code: sup.country_code,
+          node_type: 'supplier',
+          offers_count: LENGTH(offers)
+        }
+    `
+  } else {
+    aql = `
+      FOR node IN nodes
+        FILTER node.node_type == 'logistics' OR node.node_type == null
+        FILTER node.latitude != null AND node.longitude != null
+        RETURN node
+    `
+  }
+
+  const cursor = await db.query(aql)
+  let allNodes: CachedNode[] = await cursor.all()
+
+  if (transportType && (!nodeType || nodeType === 'logistics')) {
+    allNodes = allNodes.filter(n => (n.transport_types || []).includes(transportType))
+  }
+
+  nodesCache.set(cacheKey, allNodes)
+  console.log(`Cached ${allNodes.length} nodes for ${cacheKey}`)
+  return allNodes
+}
+
+export interface ClusterPoint {
+  id: string
+  latitude: number
+  longitude: number
+  count: number
+  expansion_zoom: number | null
+  name: string | null
+}
+
+export async function getClusteredNodes(
+  west: number, south: number, east: number, north: number,
+  zoom: number, transportType?: string | null, nodeType?: string | null,
+): Promise<ClusterPoint[]> {
+  const resolution = ZOOM_TO_RES[Math.floor(zoom)] ?? 5
+  const nodes = await fetchNodesAsync(transportType, nodeType)
+
+  if (!nodes.length) return []
+
+  const cells = new Map<string, CachedNode[]>()
+
+  for (const node of nodes) {
+    const lat = node.latitude
+    const lng = node.longitude
+    if (lat == null || lng == null) continue
+    if (lat < south || lat > north || lng < west || lng > east) continue
+
+    const cell = latLngToCell(lat, lng, resolution)
+    if (!cells.has(cell)) cells.set(cell, [])
+    cells.get(cell)!.push(node)
+  }
+
+  const results: ClusterPoint[] = []
+
+  for (const [cell, nodesInCell] of cells) {
+    if (nodesInCell.length === 1) {
+      const node = nodesInCell[0]
+      results.push({
+        id: node._key,
+        latitude: node.latitude!,
+        longitude: node.longitude!,
+        count: 1,
+        expansion_zoom: null,
+        name: node.name || null,
+      })
+    } else {
+      const [lat, lng] = cellToLatLng(cell)
+      results.push({
+        id: `cluster-${cell}`,
+        latitude: lat,
+        longitude: lng,
+        count: nodesInCell.length,
+        expansion_zoom: Math.min(zoom + 2, 16),
+        name: null,
+      })
+    }
+  }
+
+  return results
+}
+
+export function invalidateCache(): void {
+  nodesCache.clear()
+  console.log('Cluster cache invalidated')
+}

src/db.ts

@@ -0,0 +1,27 @@
+import { Database } from 'arangojs'
+
+const ARANGODB_URL = process.env.ARANGODB_INTERNAL_URL || 'http://localhost:8529'
+const ARANGODB_DATABASE = process.env.ARANGODB_DATABASE || 'optovia_maps'
+const ARANGODB_PASSWORD = process.env.ARANGODB_PASSWORD || ''
+
+let _db: Database | null = null
+
+export function getDb(): Database {
+  if (!_db) {
+    const url = ARANGODB_URL.startsWith('http') ? ARANGODB_URL : `http://${ARANGODB_URL}`
+    _db = new Database({ url, databaseName: ARANGODB_DATABASE, auth: { username: 'root', password: ARANGODB_PASSWORD } })
+    console.log(`Connected to ArangoDB: ${url}/${ARANGODB_DATABASE}`)
+  }
+  return _db
+}
+
+export async function ensureGraph(): Promise<void> {
+  const db = getDb()
+  const graphs = await db.listGraphs()
+  if (graphs.some(g => g.name === 'optovia_graph')) return
+
+  console.log('Creating graph: optovia_graph')
+  await db.createGraph('optovia_graph', [
+    { collection: 'edges', from: ['nodes'], to: ['nodes'] },
+  ])
+}

src/helpers.ts

@@ -0,0 +1,90 @@
+/** Haversine distance in km. */
+export function distanceKm(lat1: number, lon1: number, lat2: number, lon2: number): number {
+  const R = 6371
+  const dLat = (lat2 - lat1) * Math.PI / 180
+  const dLon = (lon2 - lon1) * Math.PI / 180
+  const a =
+    Math.sin(dLat / 2) ** 2 +
+    Math.cos(lat1 * Math.PI / 180) * Math.cos(lat2 * Math.PI / 180) *
+    Math.sin(dLon / 2) ** 2
+  return R * 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a))
+}
+
+// eslint-disable-next-line @typescript-eslint/no-explicit-any
+export type ArangoDoc = Record<string, any>
+
+export interface RouteStage {
+  from_uuid: string | null
+  from_name: string | null
+  from_lat: number | null
+  from_lon: number | null
+  to_uuid: string | null
+  to_name: string | null
+  to_lat: number | null
+  to_lon: number | null
+  distance_km: number
+  travel_time_seconds: number
+  transport_type: string | null
+}
+
+export interface RoutePath {
+  total_distance_km: number
+  total_time_seconds: number
+  stages: RouteStage[]
+}
+
+function buildStage(fromDoc: ArangoDoc | undefined, toDoc: ArangoDoc | undefined, transportType: string, edges: ArangoDoc[]): RouteStage {
+  const distance = edges.reduce((s, e) => s + (e.distance_km || 0), 0)
+  const time = edges.reduce((s, e) => s + (e.travel_time_seconds || 0), 0)
+  return {
+    from_uuid: fromDoc?._key ?? null,
+    from_name: fromDoc?.name ?? null,
+    from_lat: fromDoc?.latitude ?? null,
+    from_lon: fromDoc?.longitude ?? null,
+    to_uuid: toDoc?._key ?? null,
+    to_name: toDoc?.name ?? null,
+    to_lat: toDoc?.latitude ?? null,
+    to_lon: toDoc?.longitude ?? null,
+    distance_km: distance,
+    travel_time_seconds: time,
+    transport_type: transportType,
+  }
+}
+
+export function buildRouteFromEdges(pathEdges: [string, string, ArangoDoc][], nodeDocs: Map<string, ArangoDoc>): RoutePath | null {
+  if (!pathEdges.length) return null
+
+  // Filter offer edges — not transport stages
+  const filtered = pathEdges.filter(([, , e]) => e.transport_type !== 'offer')
+  if (!filtered.length) return null
+
+  const stages: RouteStage[] = []
+  let currentEdges: ArangoDoc[] = []
+  let currentType: string | null = null
+  let segmentStart: string | null = null
+
+  for (const [fromKey, , edge] of filtered) {
+    const edgeType = edge.transport_type as string
+    if (currentType === null) {
+      currentType = edgeType
+      currentEdges = [edge]
+      segmentStart = fromKey
+    } else if (edgeType === currentType) {
+      currentEdges.push(edge)
+    } else {
+      stages.push(buildStage(nodeDocs.get(segmentStart!), nodeDocs.get(fromKey), currentType, currentEdges))
+      currentType = edgeType
+      currentEdges = [edge]
+      segmentStart = fromKey
+    }
+  }
+
+  const lastTo = filtered[filtered.length - 1][1]
+  stages.push(buildStage(nodeDocs.get(segmentStart!), nodeDocs.get(lastTo), currentType!, currentEdges))
+
+  return {
+    total_distance_km: stages.reduce((s, st) => s + (st.distance_km || 0), 0),
+    total_time_seconds: stages.reduce((s, st) => s + (st.travel_time_seconds || 0), 0),
+    stages,
+  }
+}

src/index.ts

@@ -0,0 +1,33 @@
+import express from 'express'
+import cors from 'cors'
+import { ApolloServer } from '@apollo/server'
+import { expressMiddleware } from '@apollo/server/express4'
+import * as Sentry from '@sentry/node'
+import { typeDefs, resolvers } from './schema.js'
+
+const PORT = parseInt(process.env.PORT || '8000', 10)
+const SENTRY_DSN = process.env.SENTRY_DSN || ''
+
+if (SENTRY_DSN) {
+  Sentry.init({
+    dsn: SENTRY_DSN,
+    tracesSampleRate: 0.01,
+    release: process.env.RELEASE_VERSION || '1.0.0',
+    environment: process.env.ENVIRONMENT || 'production',
+  })
+}
+
+const app = express()
+app.use(cors({ origin: ['https://optovia.ru'], credentials: true }))
+
+const server = new ApolloServer({ typeDefs, resolvers, introspection: true })
+await server.start()
+
+app.use('/graphql/public', express.json(), expressMiddleware(server) as unknown as express.RequestHandler)
+
+app.get('/health', (_, res) => { res.json({ status: 'ok' }) })
+
+app.listen(PORT, '0.0.0.0', () => {
+  console.log(`Geo server ready on port ${PORT}`)
+  console.log(`  /graphql/public  - public (no auth)`)
+})