feat: expose RPC calls

src/main/java/com/limechain/Main.java

@@ -2,10 +2,12 @@
 
 import com.limechain.client.HostNode;
 import com.limechain.client.LightClient;
-import com.limechain.config.HostConfig;
-import com.limechain.rpc.server.AppBean;
+import com.limechain.rpc.Function;
+import com.limechain.rpc.RpcClient;
 import com.limechain.rpc.server.RpcApp;
 import com.limechain.utils.DivLogger;
+import org.teavm.jso.JSBody;
+import org.teavm.jso.core.JSString;
 
 import java.util.logging.Level;
 
@@ -20,9 +22,13 @@ public static void main(String[] args) {
 
         HostNode client = new LightClient();
 
+        exportAPI(RpcClient::sendRpcRequest, JSString.valueOf("rpc"));
         // Start the client
         // NOTE: This starts the beans the client would need - mutates the global context
         client.start();
         log.log(Level.INFO, "\uD83D\uDE80Started light client!");
     }
+
+    @JSBody(params = {"f", "apiName"}, script = "window[apiName] = f")
+    private static native void exportAPI(Function f, JSString apiName);
 }

src/main/java/com/limechain/rpc/Function.java

@@ -0,0 +1,8 @@
+package com.limechain.rpc;
+
+import org.teavm.jso.JSObject;
+
+public interface Function extends JSObject {
+
+    String sendRequest(String method, String[] params);
+}

src/main/java/com/limechain/rpc/RpcClient.java

@@ -28,6 +28,11 @@ private static String createRpcRequestJson(String method, List<Object> params) {
         return JsonUtil.stringify(request);
     }
 
+    public static String sendRpcRequest(String method, String[] params) {
+        return HttpRequest.createHttpRequest(POST, LOAD_BALANCER.getNextEndpoint(),
+            createRpcRequestJson(method, List.of(params)));
+    }
+
     protected static RpcResponse sendRpcRequest(RpcMethod method, List<Object> params) {
         String jsonResult = HttpRequest.asyncHttpRequest(POST, LOAD_BALANCER.getNextEndpoint(),
             createRpcRequestJson(method.getMethod(), params));

src/main/java/com/limechain/teavm/HttpRequest.java

@@ -17,7 +17,7 @@ public class HttpRequest {
     public static native String asyncHttpRequest(String method, String url, String body);
 
     private static void asyncHttpRequest(String method, String url, String body, AsyncCallback<String> callback) {
-        createAsyncHttpRequest(method, url, body, (error, response) -> {
+        createHttpRequest(method, url, body, (error, response) -> {
             if (error != null) {
                 log.log(Level.WARNING, error.getMessage());
             } else {
@@ -27,7 +27,10 @@ private static void asyncHttpRequest(String method, String url, String body, Asy
     }
 
     @JSBody(params = {"method", "url", "body", "callback"}, script = "return asyncHttpRequest(method, url, body, callback);")
-    private static native void createAsyncHttpRequest(String method, String url, String body, HttpRequestCallback callback);
+    private static native void createHttpRequest(String method, String url, String body, HttpRequestCallback callback);
+
+    @JSBody(params = {"method", "url", "body"}, script = "return httpRequestSync(method, url, body);")
+    public static native String createHttpRequest(String method, String url, String body);
 
     @JSFunctor
     private interface HttpRequestCallback extends JSObject {

src/main/webapp/js/http.js

@@ -19,4 +19,20 @@ async function asyncHttpRequest(method = 'GET', url, body = null, callback) {
     } catch (error) {
         callback(new Error(`Error during sending request: ${error?.message}`), null);
     }
-}
+}
+
+function httpRequestSync(method, url, body) {
+    var xhr = new XMLHttpRequest();
+    xhr.open(method, url, false); // false for synchronous request
+    xhr.setRequestHeader('Content-Type', 'application/json');
+    if (method === 'POST' && body) {
+        xhr.send(body);
+    } else {
+        xhr.send();
+    }
+    if (xhr.status === 200) {
+        return xhr.responseText;
+    } else {
+        throw new Error('Request failed with status ' + xhr.status);
+    }
+}