path endpoint added with dijkstra algorithm

app.js

@@ -17,6 +17,7 @@ var swapRouter = require("./routes/swaproutes");
 var pairRouter = require("./routes/pairroutes");
 var erc20Router = require("./routes/erc20routes");
 var coinsmarketcapapiRouter = require("./routes/coinsmarketcapapi");
+var pathRouter = require("./routes/pathroutes");
 
 // view engine setup
 app.set("views", path.join(__dirname, "views"));
@@ -79,6 +80,7 @@ app.use("/", swapRouter);
 app.use("/", pairRouter);
 app.use("/", erc20Router);
 app.use("/", coinsmarketcapapiRouter);
+app.use("/", pathRouter);
 
 app.use(
   "/graphql",

package.json

@@ -28,6 +28,7 @@
     "jade": "~1.11.0",
     "mongoose": "^6.0.8",
     "morgan": "~1.9.1",
+    "node-dijkstra": "^2.5.0",
     "nodemon": "^2.0.13",
     "prettier": "^2.3.2",
     "request": "^2.88.2",

routes/pathroutes.js

@@ -0,0 +1,108 @@
+require("dotenv").config();
+var express = require("express");
+var router = express.Router();
+var pair = require("../models/pair");
+const Graph = require("node-dijkstra");
+const { consoleTestResultHandler } = require("tslint/lib/test");
+
+router.route("/getpath").post(async function (req, res, next) {
+  try {
+    if (!req.body.tokenASymbol) {
+      return res.status(400).json({
+        success: false,
+        message: "tokenASymbol not found in the request Body.",
+      });
+    }
+    if (!req.body.tokenBSymbol) {
+      return res.status(400).json({
+        success: false,
+        message: "tokenBSymbol not found in the request Body.",
+      });
+    }
+
+    let pairs = await pair.find({});
+    if (pairs.length == 0) {
+      return res.status(400).json({
+        success: false,
+        message: "There is no pair in the database.",
+      });
+    } else {
+
+      const graph = new Map();
+
+      for (var i = 0; i < pairs.length; i++) {
+        let token0 = pairs[i].token0.symbol;
+        let token1 = pairs[i].token1.symbol;
+        let pairswithtoken0 = [];
+        let pairswithtoken1 = [];
+        for (var j = 0; j < pairs.length; j++) {
+          if (pairs[j].token0.symbol == token0) {
+            pairswithtoken0.push(pairs[j].token1.symbol);
+          }
+          if (pairs[j].token1.symbol == token0) {
+            pairswithtoken0.push(pairs[j].token0.symbol);
+          }
+          if (pairs[j].token0.symbol == token1) {
+            pairswithtoken1.push(pairs[j].token1.symbol);
+          }
+          if (pairs[j].token1.symbol == token1) {
+            pairswithtoken1.push(pairs[j].token0.symbol);
+          }
+        }
+        const a = new Map();
+        for (var z = 0; z < pairswithtoken0.length; z++) {
+          a.set(pairswithtoken0[z], 1);
+        }
+        graph.set(token0, a);
+
+        const b = new Map();
+        for (var z = 0; z < pairswithtoken1.length; z++) {
+          b.set(pairswithtoken1[z], 1);
+        }
+        graph.set(token1, b);
+      }
+      const route = new Graph(graph);
+      console.log("graph: ",graph);
+      let path = route.path(req.body.tokenASymbol, req.body.tokenBSymbol);
+      if (path != null) {
+        let pathwithcontractHash = [];
+        for(var i=0;i<path.length;i++)
+        {
+            for(var j=0;j<pairs.length;j++)
+            {
+                if(pairs[j].token0.symbol==path[i])
+                {
+                    pathwithcontractHash.push(pairs[j].token0.id);
+                    break;
+                }
+                if(pairs[j].token1.symbol==path[i])
+                {
+                    pathwithcontractHash.push(pairs[j].token1.id);
+                    break;
+                }
+            }
+        }
+        return res.status(200).json({
+          success: true,
+          message: "Path found against these tokens.",
+          path: path,
+          pathwithcontractHash: pathwithcontractHash,
+        });
+      } else {
+        return res.status(400).json({
+          success: false,
+          message: "Path not found against these tokens.",
+          path: path,
+        });
+      }
+    }
+  } catch (error) {
+    console.log("error (try-catch) : " + error);
+    return res.status(500).json({
+      success: false,
+      err: error,
+    });
+  }
+});
+
+module.exports = router;

test.js

@@ -23,21 +23,58 @@
 // var j=parseFloat(i);
 // console.log("j: ",j);
 
-var a = BigInt(
-  "782910138827292261791972728324982565756575668687686786786786787686786786"
-);
-var b = BigInt(
-  "782910138827292261791972728324982565756575668687686786786786787686786786"
-);
-
-console.log(a);
-console.log(b.toString());
-console.log((a * b).toString());
-console.log(((a * b) / b).toString());
-
-console.log(BigInt(000000000));
-console.log(2 * 1 + (9 + 1) * 3);
-if(BigInt(1)>BigInt(0))
-{
-  console.log(2 * 1 + (9 + 1) * 3);
-}
+// var a = BigInt(
+//   "782910138827292261791972728324982565756575668687686786786786787686786786"
+// );
+// var b = BigInt(
+//   "782910138827292261791972728324982565756575668687686786786786787686786786"
+// );
+
+// console.log(a);
+// console.log(b.toString());
+// console.log((a * b).toString());
+// console.log(((a * b) / b).toString());
+
+// console.log(BigInt(000000000));
+// console.log(2 * 1 + (9 + 1) * 3);
+// if(BigInt(1)>BigInt(0))
+// {
+//   console.log(2 * 1 + (9 + 1) * 3);
+// }
+
+ const Graph = require('node-dijkstra');
+
+const route = new Graph();
+
+route.addNode('WCSPR', { WISER:1 });
+route.addNode('WISER', { WCSPR:1 ,USDC:1 });
+route.addNode('USDC', { WISER:1, USDT:1,WETH:1});
+route.addNode('USDT', { USDC:1 });
+route.addNode('ETH', { WETH:1 });
+route.addNode('WETH', { ETH:1 ,USDC:1});
+
+console.log("graph: ",route);
+console.log("path: ",route.path('WCSPR', 'USDC'));
+console.log("path: ",route.path('WISER', 'USDT'));
+console.log("path: ",route.path('USDT', 'WISER'));
+console.log("path: ",route.path('WCSPR', 'ETH'));
+console.log("path: ",route.path('ETH','WETH'));
+console.log("path: ",route.path('WETH','ETH'));
+
+
+
+// const graph = new Map()
+
+// const a = new Map()
+// a.set('B', 1)
+
+// const b = new Map()
+// b.set('C', 1)
+
+
+// graph.set('A', a)
+// graph.set('B', b);
+
+// const route = new Graph(graph)
+
+// console.log("path: ",route.path('A', 'C'));