DLOBApiClient init

sdk/src/dlob/DLOBApiClient.ts

@@ -0,0 +1,33 @@
+import fetch from 'node-fetch';
+import { DLOBOrdersCoder } from './DLOBOrders';
+import { DLOB } from './DLOB';
+
+type DLOBApiClientConfig = {
+	url: string;
+};
+
+export class DLOBApiClient {
+	url: string;
+	dlobCoder = DLOBOrdersCoder.create();
+	lastSeenDLOB: DLOB;
+	lastSeenSlot = 0;
+
+	constructor(config: DLOBApiClientConfig) {
+		this.url = config.url;
+	}
+
+	public async getDLOB(slot: number): Promise<DLOB> {
+		const r = await fetch(this.url);
+		const resp = await r.json();
+		const responseSlot = resp['slot'];
+		if (responseSlot > this.lastSeenSlot) {
+			const dlobOrdersBuffer = Buffer.from(resp['data'], 'base64');
+			const dlobOrders = this.dlobCoder.decode(Buffer.from(dlobOrdersBuffer));
+			const dlob = new DLOB();
+			dlob.initFromOrders(dlobOrders, slot);
+			this.lastSeenDLOB = dlob;
+			this.lastSeenSlot = responseSlot;
+		}
+		return this.lastSeenDLOB;
+	}
+}

sdk/src/dlob/DLOBSubscriber.ts

@@ -33,7 +33,7 @@ export class DLOBSubscriber {
 		this.intervalId = setInterval(async () => {
 			await this.updateDLOB();
 			this.eventEmitter.emit('update', this.dlob);
-		});
+		}, this.updateFrequency);
 	}
 
 	async updateDLOB(): Promise<void> {