Merge pull request #111 from Kanahiro/feat/cog

feat: support `cog://` protocol

.gitignore

@@ -2,4 +2,5 @@
 node_modules/
 dist/
 .cache/
-coverage/
+coverage/
+package-lock.json

README.md

@@ -191,6 +191,13 @@ node dist/main.js tile-server -c s3 -s3b chiitiler -s3r ap-northeast-1
         "s3://tiles/{z}/{x}/{y}.pbf"
       ],
       "maxzoom": 6
+    },
+    "cog": {
+      "type": "raster",
+      "tiles": [
+        "cog://https://sentinel-cogs.s3.us-west-2.amazonaws.com/sentinel-s2-l2a-cogs/54/T/WN/2024/9/S2A_54TWN_20240908_0_L2A/TCI.tif/{z}/{x}/{y}"
+      ],
+      "tileSize": 256
     }
   },
   "layers": [
@@ -233,6 +240,14 @@ node dist/main.js tile-server -c s3 -s3b chiitiler -s3r ap-northeast-1
         "circle-radius": 3,
         "circle-color": "green"
       }
+    },
+    {
+      "id": "cog",
+      "source": "cog",
+      "type": "raster",
+      "paint": {
+        "raster-opacity": 0.5
+      }
     }
   ]
 }

localdata/style.json

@@ -1,6 +1,13 @@
 {
-  "version": "8",
+  "version": 8,
   "sources": {
+    "osm": {
+      "type": "raster",
+      "tiles": [
+        "https://tile.openstreetmap.org/{z}/{x}/{y}.png"
+      ],
+      "tileSize": 256
+    },
     "dir": {
       "type": "vector",
       "tiles": [
@@ -35,9 +42,22 @@
         "pmtiles://s3://tiles/school.pmtiles/{z}/{x}/{y}"
       ],
       "maxzoom": 10
+    },
+    "cog": {
+      "type": "raster",
+      "tiles": [
+        "cog://https://sentinel-cogs.s3.us-west-2.amazonaws.com/sentinel-s2-l2a-cogs/54/T/WN/2024/9/S2A_54TWN_20240908_0_L2A/TCI.tif/{z}/{x}/{y}"
+      ],
+      "tileSize": 256
     }
   },
   "layers": [
+    {
+      "id": "osm",
+      "source": "osm",
+      "type": "raster",
+      "paint": {}
+    },
     {
       "id": "dir",
       "source": "dir",
@@ -87,6 +107,14 @@
         "circle-radius": 3,
         "circle-color": "purple"
       }
+    },
+    {
+      "id": "cog",
+      "source": "cog",
+      "type": "raster",
+      "paint": {
+        "raster-opacity": 0.8
+      }
     }
   ]
 }

package.json

@@ -1,7 +1,7 @@
 {
   "type": "module",
   "name": "chiitiler",
-  "version": "1.13.0",
+  "version": "1.14.0",
   "description": "Tiny map rendering server for MapLibre Style Spec",
   "main": "./dist/index.js",
   "types": "./dist/index.d.ts",
@@ -43,10 +43,11 @@
     "better-sqlite3": "^9.6.0",
     "commander": "^11.0.0",
     "file-system-cache": "^2.4.4",
+    "higuruma": "^0.1.6",
     "hono": "^4.5.4",
     "lightning-pool": "^4.2.2",
     "lru-cache": "^11.0.0",
     "pmtiles": "^3.0.5",
     "sharp": "^0.32.5"
   }
-}
+}

src/render/pool.ts

@@ -25,6 +25,8 @@ const TRANSPARENT_BUFFER: Record<string, Buffer> = {
 };
 
 function handleFileExt(uri: string) {
+    if (uri.startsWith('cog://')) return 'png'; // cog:// always returns as png
+
     // extract extension only, take into account query string or hash
     const basename = path.basename(uri).split(/[?#]/)[0];
     const ext = basename.split('.').pop();

src/source/cog.ts

@@ -0,0 +1,21 @@
+/// <reference lib="dom" />
+// for using native fetch in TypeScript
+
+import { renderTile } from 'higuruma';
+
+async function getCogSource(uri: string): Promise<Buffer | null> {
+    const cogPath = uri.replace('cog://', '').replace(/\/\d+\/\d+\/\d+$/, '');
+    const [z, x, y] = uri.replace(`cog://${cogPath}/`, '').split('/');
+
+    try {
+        const tile = await renderTile(cogPath, Number(z), Number(x), Number(y));
+        const buf = Buffer.from(tile);
+        if (buf.byteLength === 129) return null; // empty tile
+        return buf;
+    } catch (e) {
+        console.error(`[ERROR] ${e}`);
+        return null;
+    }
+}
+
+export { getCogSource };

src/source/index.test.ts

@@ -27,6 +27,13 @@ describe('getSource', () => {
         expect(data).not.toBeNull();
     });
 
+    it('cog://', async () => {
+        const uri =
+            'cog://https://sentinel-cogs.s3.us-west-2.amazonaws.com/sentinel-s2-l2a-cogs/54/T/WN/2024/9/S2A_54TWN_20240908_0_L2A/TCI.tif/6/32/24';
+        const data = await getSource(uri);
+        expect(data).not.toBeNull();
+    });
+
     it('invalid uri', async () => {
         const uri = 'invalid://localdata/style.json';
         const data = await getSource(uri);

src/source/index.ts

@@ -3,6 +3,7 @@ import { getHttpSource } from './http.js';
 import { getPmtilesSoruce } from './pmtiles.js';
 import { getMbtilesSource } from './mbtiles.js';
 import { getS3Source } from './s3.js';
+import { getCogSource } from './cog.js';
 import { Cache, noneCache } from '../cache/index.js';
 
 /**
@@ -24,6 +25,8 @@ async function getSource(
     else if (uri.startsWith('mbtiles://')) data = await getMbtilesSource(uri);
     else if (uri.startsWith('pmtiles://'))
         data = await getPmtilesSoruce(uri, cache);
+    else if (uri.startsWith('cog://')) data = await getCogSource(uri);
+    else return null;
 
     return data;
 }