From c0259e3ecb29cbf16d8e694655974e4124604e6e Mon Sep 17 00:00:00 2001
From: "Michael Bradley, Jr" <michaelsbradleyjr@gmail.com>
Date: Sun, 15 Jul 2018 19:34:33 -0500
Subject: [PATCH] proxy -- canonicalHost, defaultHost

---
 lib/core/proxy.js | 127 ++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 127 insertions(+)
 create mode 100644 lib/core/proxy.js

diff --git a/lib/core/proxy.js b/lib/core/proxy.js
new file mode 100644
index 000000000..ce3ed4b18
--- /dev/null
+++ b/lib/core/proxy.js
@@ -0,0 +1,127 @@
+const httpProxy = require('http-proxy');
+const http = require('http');
+const constants = require('../constants.json');
+
+let commList = {};
+let transactions = {};
+let receipts = {};
+
+const {canonicalHost, defaultHost} = require('../utils/host');
+
+const parseRequest = function(reqBody){
+    let jsonO;
+    try {
+        jsonO = JSON.parse(reqBody);
+    } catch(e){
+        return; // Request is not a json. Do nothing
+    }
+    if(jsonO.method === "eth_sendTransaction"){
+        commList[jsonO.id] = {
+            type: 'contract-log',
+            address: jsonO.params[0].to,
+            data: jsonO.params[0].data
+        };
+    } else if(jsonO.method === "eth_getTransactionReceipt"){
+        if(transactions[jsonO.params[0]]){
+            transactions[jsonO.params[0]].receiptId = jsonO.id;
+            receipts[jsonO.id] = transactions[jsonO.params[0]].commListId;
+        }
+    }
+};
+
+const parseResponse = function(ipc, resBody){
+    let jsonO;
+    try {
+        jsonO = JSON.parse(resBody);
+    } catch(e) {
+        return; // Response is not a json. Do nothing
+    }
+
+    if(commList[jsonO.id]){
+        commList[jsonO.id].transactionHash = jsonO.result;
+        transactions[jsonO.result] = {commListId: jsonO.id};
+    } else if(receipts[jsonO.id] && jsonO.result && jsonO.result.blockNumber){
+        commList[receipts[jsonO.id]].blockNumber = jsonO.result.blockNumber;
+        commList[receipts[jsonO.id]].gasUsed = jsonO.result.gasUsed;
+        commList[receipts[jsonO.id]].status = jsonO.result.status;
+
+        if(ipc.connected && !ipc.connecting){
+            ipc.request('log', commList[receipts[jsonO.id]]);
+        } else {
+            ipc.connecting = true;
+            ipc.connect(() => {
+                ipc.connecting = false;
+            });
+        }
+
+        delete transactions[commList[receipts[jsonO.id]].transactionHash];
+        delete receipts[jsonO.id];
+        delete commList[jsonO.id];
+    }
+};
+
+exports.serve = function(ipc, host, port, ws){
+    let proxy = httpProxy.createProxyServer({
+        target: {
+            host: canonicalHost(host),
+            port: port + constants.blockchain.servicePortOnProxy
+          },
+        ws: ws
+    });
+
+    proxy.on('error', function (e) {
+        console.error(__("Error forwarding requests to blockchain/simulator"), e.message);
+    });
+
+    proxy.on('proxyRes', (proxyRes) => {
+        let resBody = [];
+        proxyRes.on('data', (b) => resBody.push(b));
+        proxyRes.on('end', function () {
+            resBody = Buffer.concat(resBody).toString();
+            if(resBody){
+                parseResponse(ipc, resBody);
+            }
+        });
+    });
+
+    let server = http.createServer((req, res) => {
+        let reqBody = [];
+        req.on('data', (b) => { reqBody.push(b); })
+            .on('end', () => {
+                reqBody = Buffer.concat(reqBody).toString();
+                if(reqBody){
+                    parseRequest(reqBody);
+                }
+            });
+
+        if(!ws){
+            proxy.web(req, res);
+        }
+    });
+
+    if(ws){
+        const WsParser = require('simples/lib/parsers/ws'); // npm install simples
+
+        server.on('upgrade', function (req, socket, head) {
+            proxy.ws(req, socket, head);
+        });
+
+        proxy.on('open', (proxySocket) => {
+            proxySocket.on('data', (data) => {
+                parseResponse(ipc, data.toString().substr(data.indexOf("{")));
+            });
+        });
+
+         proxy.on('proxyReqWs', (proxyReq, req, socket) => {
+             var parser = new WsParser(0, false);
+             socket.pipe(parser);
+             parser.on('frame', function (frame) {
+                parseRequest(frame.data);
+             });
+
+         });
+    }
+
+    server.listen(port, defaultHost);
+    return server;
+};