Liquid icons api

backend/src/api/liquid/icons.ts

@@ -0,0 +1,39 @@
+import * as fs from 'fs';
+import config from '../../config';
+import logger from '../../logger';
+
+class Icons {
+  private static FILE_NAME = './icons.json';
+  private iconIds: string[] = [];
+  private icons: { [assetId: string]: string; } = {};
+  constructor() {
+    if (config.MEMPOOL.NETWORK !== 'liquid') {
+      return;
+    }
+    if (!fs.existsSync(Icons.FILE_NAME)) {
+      logger.warn(`${Icons.FILE_NAME} does not exist. No Liquid icons loaded.`);
+      return;
+    }
+    const cacheData = fs.readFileSync(Icons.FILE_NAME, 'utf8');
+    this.icons = JSON.parse(cacheData);
+
+    for (const i in this.icons) {
+      this.iconIds.push(i);
+    }
+    logger.debug(`Liquid icons has been loaded.`);
+  }
+
+  public getIconByAssetId(assetId: string): Buffer | undefined {
+    const icon = this.icons[assetId];
+    if (icon) {
+      return Buffer.from(icon, 'base64');
+    }
+  }
+
+  public getAllIconIds() {
+    return this.iconIds;
+  }
+
+}
+
+export default new Icons();

backend/src/index.ts

@@ -270,6 +270,13 @@ class Server {
       ;
     }
 
+    if (config.MEMPOOL.NETWORK === 'liquid') {
+      this.app
+        .get(config.MEMPOOL.API_URL_PREFIX + 'liquid/icons', routes.getAllLiquidIcon)
+        .get(config.MEMPOOL.API_URL_PREFIX + 'liquid/icon/:assetId', routes.getLiquidIcon)
+      ;
+    }
+
     if (config.MEMPOOL.NETWORK === 'liquid' && config.DATABASE.ENABLED) {
       this.app
         .get(config.MEMPOOL.API_URL_PREFIX + 'liquid/pegs/month', routes.$getElementsPegsByMonth)

backend/src/routes.ts

@@ -19,6 +19,7 @@ import loadingIndicators from './api/loading-indicators';
 import { Common } from './api/common';
 import bitcoinClient from './api/bitcoin/bitcoin-client';
 import elementsParser from './api/liquid/elements-parser';
+import icons from './api/liquid/icons';
 
 class Routes {
   constructor() {}
@@ -807,6 +808,26 @@ class Routes {
         : (e.message || 'Error'));
     }
   }
+
+  public getLiquidIcon(req: Request, res: Response) {
+    const result = icons.getIconByAssetId(req.params.assetId);
+    if (result) {
+      res.setHeader('content-type', 'image/png');
+      res.setHeader('content-length', result.length);
+      res.send(result);
+    } else {
+      res.status(404).send('Asset icon not found');
+    }
+  }
+
+  public getAllLiquidIcon(req: Request, res: Response) {
+    const result = icons.getAllIconIds();
+    if (result) {
+      res.json(result);
+    } else {
+      res.status(404).send('Asset icons not found');
+    }
+  }
 }
 
 export default new Routes();