Updated js-example to get gateway from topology (#225)

Cargo.lock

@@ -1629,7 +1629,7 @@ dependencies = [
 
 [[package]]
 name = "nym-client-wasm"
-version = "0.1.2"
+version = "0.1.3"
 dependencies = [
  "console_error_panic_hook",
  "crypto",

clients/webassembly/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "nym-client-wasm"
-version = "0.1.2"
+version = "0.1.3"
 authors = ["Dave Hrycyszyn <futurechimp@users.noreply.github.com>", "Jedrzej Stuczynski <andrew@nymtech.net>"]
 edition = "2018"
 repository = "https://github.com/nymtech/nym"

clients/webassembly/helpers.js

@@ -8,6 +8,14 @@ export function makeAuthenticateRequest(address, token) {
     return JSON.stringify({ "type": "authenticate", "address": address, "token": token });
 }
 
+export async function getInitialGatewayAddress(directoryUrl) {
+    const topology = await getTopology(directoryUrl);
+    if (topology.gatewayNodes.length > 0) {
+        return topology.gatewayNodes[0].clientListener;
+    } 
+    return "";
+}
+
 // NOTE: this currently does not implement chunking and too long messages will cause a panic
 export function makeSendablePacket(topology, message, recipient) {
     return wasm.create_gateway_sphinx_packet(topology, message, recipient);

clients/webassembly/js-example/index.js

@@ -13,7 +13,7 @@
 // limitations under the License.
 
 import * as wasm from "nym-client-wasm";
-import { makeRegisterRequest, makeAuthenticateRequest, makeSendablePacket, getTopology } from "nym-client-wasm/helpers"
+import { makeRegisterRequest, makeAuthenticateRequest, makeSendablePacket, getTopology, getInitialGatewayAddress } from "nym-client-wasm/helpers"
 
 class GatewayConnection {
     constructor(gateway_url, ownAddress, registeredCallback) {
@@ -121,10 +121,14 @@ function sleep(ms) {
     return new Promise(resolve => setTimeout(resolve, ms));
 }
 
-function main() {
-    var gatewayUrl = "ws://127.0.0.1:1977";
+async function main() {
     var directoryUrl = "http://127.0.0.1:8080/api/presence/topology";
 
+    const gatewayUrl = await getInitialGatewayAddress(directoryUrl);
+    if (gatewayUrl == "") {
+        alert("No gateways detected - cannot procede");
+        return;
+    }
 
     // NOTE: in an actual application, you should save those keys somewhere and only generate them a single time
     // then reuse them in subsequent runs

clients/webassembly/js-example/package.json

@@ -27,7 +27,7 @@
   },
   "homepage": "https://github.com/rustwasm/create-wasm-app#readme",
   "dependencies": {
-    "nym-client-wasm": "^0.1.2"
+    "nym-client-wasm": "^0.1.3"
   },
   "devDependencies": {
     "hello-wasm-pack": "^0.1.0",
@@ -36,4 +36,4 @@
     "webpack-dev-server": "^3.1.5",
     "copy-webpack-plugin": "^5.0.0"
   }
-}
+}

clients/webassembly/js-example/yarn.lock

@@ -2484,10 +2484,10 @@ number-is-nan@^1.0.0:
   resolved "https://registry.yarnpkg.com/number-is-nan/-/number-is-nan-1.0.1.tgz#097b602b53422a522c1afb8790318336941a011d"
   integrity sha1-CXtgK1NCKlIsGvuHkDGDNpQaAR0=
 
-nym-client-wasm@^0.1.2:
-  version "0.1.2"
-  resolved "https://registry.yarnpkg.com/nym-client-wasm/-/nym-client-wasm-0.1.2.tgz#1a89b28eafaff61de7d71b9045c2c6f76813d8e0"
-  integrity sha512-G4Nsw+abk/UC5PbvxiEspMiq2EAXWOFvsXLGVkS2fzg2WxRlkf8hXoRK8mbgeqFlOB0LDf8ZSauI4eyqu0UPFw==
+nym-client-wasm@^0.1.3:
+  version "0.1.3"
+  resolved "https://registry.yarnpkg.com/nym-client-wasm/-/nym-client-wasm-0.1.3.tgz#49f93a6a6db0e26dfe94337625a69ea922b05cda"
+  integrity sha512-ce8JojJ5sXIuY2hbFmgo2W1Nyy56uQ8GnsG6yBt3rzu6+seIRdxPd5ilN86L0Ps7uYLpAyydcwWLErjR6W9S+g==
 
 object-assign@^4.0.1, object-assign@^4.1.1:
   version "4.1.1"