wip: local tileserver

server/src/controllers/map.controller.ts

@@ -1,5 +1,10 @@
-import { Controller, Get, HttpCode, HttpStatus, Query } from '@nestjs/common';
+import { Controller, Get, NotFoundException, Param, HttpCode, HttpStatus, Query, Res } from '@nestjs/common';
 import { ApiTags } from '@nestjs/swagger';
+import { Response } from 'express';
+import fsSync from 'node:fs';
+import fs from 'node:fs/promises';
+// @ts-expect-error test
+import { PMTiles, RangeResponse, Source } from 'pmtiles';
 import { AuthDto } from 'src/dtos/auth.dto';
 import {
   MapMarkerDto,
@@ -16,6 +21,9 @@ import { MapService } from 'src/services/map.service';
 export class MapController {
   constructor(private service: MapService) {}
 
+  source = new FileSource('./resources/v1.pmtiles');
+  pmtiles = new PMTiles(this.source);
+
   @Get('markers')
   @Authenticated()
   getMapMarkers(@Auth() auth: AuthDto, @Query() options: MapMarkerDto): Promise<MapMarkerResponseDto[]> {
@@ -34,4 +42,83 @@ export class MapController {
   reverseGeocode(@Query() dto: MapReverseGeocodeDto): Promise<MapReverseGeocodeResponseDto[]> {
     return this.service.reverseGeocode(dto);
   }
+
+  @Get('tiles.json')
+  async getTilesJson() {
+    // eslint-disable-next-line unicorn/no-await-expression-member
+    return JSON.parse((await fs.readFile(`./resources/tiles.json`)).toString());
+  }
+
+  @Get('tiles/:z/:x/:y.:format')
+  async getTiles(
+    @Param('z') z: number,
+    @Param('x') x: number,
+    @Param('y') y: number,
+    @Param('format') format: string,
+    @Res({ passthrough: true }) res: Response,
+  ) {
+    // load data based on tile request
+    console.log('getting tile');
+    const tile = await this.pmtiles.getZxy(Number(z), Number(x), Number(y));
+    console.log('tile', tile);
+    if (!tile) {
+      throw new NotFoundException('Tile not found.');
+    }
+    console.log('getting');
+    const data = Buffer.from(tile.data);
+    console.log('got buffer');
+
+    // determine content-type header based on data
+    // (assume pbf for now)
+    console.log('getting header');
+    const header = await this.pmtiles.getHeader();
+    console.log('header', header);
+    switch (header.tileType) {
+      case 0: {
+        console.log('Unknown tile type.');
+        break;
+      }
+      case 1: {
+        res.setHeader('Content-Type', 'application/x-protobuf');
+        break;
+      }
+    }
+
+    res.status(200).send(data);
+  }
+}
+
+class FileSource implements Source {
+  filename: string;
+  fileDescriptor: number;
+
+  constructor(filename: string) {
+    this.filename = filename;
+    this.fileDescriptor = fsSync.openSync(filename, 'r');
+  }
+
+  getKey() {
+    return this.filename;
+  }
+
+  // helper async function to read in bytes from file
+  readBytesIntoBuffer = async (buffer: Buffer, offset: number) =>
+    new Promise<void>((resolve, reject) => {
+      fsSync.read(this.fileDescriptor, buffer, 0, buffer.length, offset, (err) => {
+        if (err) {
+          return reject(err);
+        }
+        resolve();
+      });
+    });
+
+  getBytes = async (offset: number, length: number) => {
+    // create buffer and read in byes from file
+    const buffer = Buffer.alloc(length);
+    await this.readBytesIntoBuffer(buffer, offset);
+
+    const data = buffer.buffer.slice(buffer.byteOffset, buffer.byteOffset + buffer.byteLength);
+
+    return { data } as RangeResponse;
+  };
 }