From e7f60e9abdc7ac1bd9eca542152b74b5e13ca43d Mon Sep 17 00:00:00 2001
From: Simon Warta <simon@warta.it>
Date: Sat, 7 Mar 2020 17:30:43 +0100
Subject: [PATCH] Add CosmWasmClient.getHeight()

---
 packages/bcp/src/cosmwasmconnection.ts  |  3 +--
 packages/sdk/src/cosmwasmclient.spec.ts | 14 +++++++++++++-
 packages/sdk/src/cosmwasmclient.ts      |  7 +++++++
 packages/sdk/types/cosmwasmclient.d.ts  |  1 +
 4 files changed, 22 insertions(+), 3 deletions(-)

diff --git a/packages/bcp/src/cosmwasmconnection.ts b/packages/bcp/src/cosmwasmconnection.ts
index 275bd81b..e872c9dc 100644
--- a/packages/bcp/src/cosmwasmconnection.ts
+++ b/packages/bcp/src/cosmwasmconnection.ts
@@ -138,8 +138,7 @@ export class CosmWasmConnection implements BlockchainConnection {
   }
 
   public async height(): Promise<number> {
-    const { header } = await this.cosmWasmClient.getBlock();
-    return header.height;
+    return this.cosmWasmClient.getHeight();
   }
 
   public async getToken(searchTicker: TokenTicker): Promise<Token | undefined> {
diff --git a/packages/sdk/src/cosmwasmclient.spec.ts b/packages/sdk/src/cosmwasmclient.spec.ts
index 660c9e23..563c2221 100644
--- a/packages/sdk/src/cosmwasmclient.spec.ts
+++ b/packages/sdk/src/cosmwasmclient.spec.ts
@@ -1,7 +1,7 @@
 /* eslint-disable @typescript-eslint/camelcase */
 import { Sha256 } from "@iov/crypto";
 import { Bech32, Encoding } from "@iov/encoding";
-import { assert } from "@iov/utils";
+import { assert, sleep } from "@iov/utils";
 import { ReadonlyDate } from "readonly-date";
 
 import { Code, CosmWasmClient } from "./cosmwasmclient";
@@ -56,6 +56,18 @@ describe("CosmWasmClient", () => {
     });
   });
 
+  describe("getHeight", () => {
+    it("works", async () => {
+      pendingWithoutWasmd();
+      const client = new CosmWasmClient(wasmdEndpoint);
+      const height1 = await client.getHeight();
+      expect(height1).toBeGreaterThan(0);
+      await sleep(1_000);
+      const height2 = await client.getHeight();
+      expect(height2).toEqual(height1 + 1);
+    });
+  });
+
   describe("getNonce", () => {
     it("works", async () => {
       pendingWithoutWasmd();
diff --git a/packages/sdk/src/cosmwasmclient.ts b/packages/sdk/src/cosmwasmclient.ts
index 9c62f69d..43c5f580 100644
--- a/packages/sdk/src/cosmwasmclient.ts
+++ b/packages/sdk/src/cosmwasmclient.ts
@@ -149,6 +149,13 @@ export class CosmWasmClient {
     return response.node_info.network;
   }
 
+  public async getHeight(): Promise<number> {
+    // Note: this gets inefficient when blocks contain a lot of transactions since it
+    // requires downloading and deserializing all transactions in the block.
+    const latest = await this.restClient.blocksLatest();
+    return parseInt(latest.block.header.height, 10);
+  }
+
   /**
    * Returns a 32 byte upper-case hex transaction hash (typically used as the transaction ID)
    */
diff --git a/packages/sdk/types/cosmwasmclient.d.ts b/packages/sdk/types/cosmwasmclient.d.ts
index 83afe61f..c9a2f600 100644
--- a/packages/sdk/types/cosmwasmclient.d.ts
+++ b/packages/sdk/types/cosmwasmclient.d.ts
@@ -107,6 +107,7 @@ export declare class CosmWasmClient {
   protected readonly restClient: RestClient;
   constructor(url: string, broadcastMode?: BroadcastMode);
   chainId(): Promise<string>;
+  getHeight(): Promise<number>;
   /**
    * Returns a 32 byte upper-case hex transaction hash (typically used as the transaction ID)
    */