chore(loader): update dependencies and add wasm-metering #1016

loader/package.json

@@ -20,7 +20,9 @@
     "test": "npm run build && node --experimental-wasm-memory64 --test",
     "test:integration": "npm run build && MODULE_PATH='../dist/index.cjs' node --experimental-wasm-memory64 --test"
   },
-  "dependencies": {},
+  "dependencies": {
+    "@permaweb/wasm-metering": "^0.2.2"
+  },
   "devDependencies": {
     "esbuild": "^0.19.5",
     "typescript": "^5.2.2"

loader/src/formats/wasm64-emscripten.cjs

@@ -20,7 +20,7 @@ var Module = (() => {
         limit: Module.computeLimit || DEFAULT_GAS_LIMIT,
         used: 0,
         use: (amount) => {
-          Module.gas.used += amount;
+          Module.gas.used += Number(amount);
         },
         refill: (amount) => {
           if (!amount) Module.gas.used = 0;

loader/src/index.cjs

@@ -3,6 +3,7 @@ const Emscripten2 = require('./formats/emscripten2.cjs')
 const Emscripten3 = require('./formats/emscripten3.cjs')
 const Emscripten4 = require('./formats/emscripten4.cjs')
 const Wasm64 = require('./formats/wasm64-emscripten.cjs')
+const metering = require('@permaweb/wasm-metering')
 
 /* eslint-enable */
 
@@ -93,6 +94,10 @@ const Wasm64 = require('./formats/wasm64-emscripten.cjs')
 module.exports = async function (binary, options) {
   let instance = null
   let doHandle = null
+
+  let meterType = options.format.startsWith("wasm32") ? "i32" : "i64";
+  const originalInstantiate = WebAssembly.instantiate;
+
   if (options === null) {
     options = { format: 'wasm32-unknown-emscripten' }
   }
@@ -105,15 +110,20 @@ module.exports = async function (binary, options) {
   } else {
 
     if (typeof binary === "function") {
+      WebAssembly.instantiate = async function (wasm, info) {
+        const meteredWasm = metering.meterWASM(wasm, { meterType });
+        return originalInstantiate(meteredWasm, info);
+      };
       options.instantiateWasm = binary
     } else {
+      binary = metering.meterWASM(binary, { meterType })
       options.wasmBinary = binary
     }
 
     if (options.format === "wasm64-unknown-emscripten-draft_2024_02_15") {
       instance = await Wasm64(options)
     } else if (options.format === "wasm32-unknown-emscripten4") {
-      instance = await Emscripten4(binary, options)
+      instance = await Emscripten4(options)
     }
 
     await instance['FS_createPath']('/', 'data')
@@ -141,6 +151,9 @@ module.exports = async function (binary, options) {
     doHandle = instance.cwrap('handle', 'string', ['string', 'string'])
   }
 
+  if (typeof binary === "function") {
+    WebAssembly.instantiate = originalInstantiate;
+  }
 
   return async (buffer, msg, env) => {
     const originalRandom = Math.random

loader/test/index.test.js

@@ -118,7 +118,7 @@ describe('loader', async () => {
      * but they should be within ~75k of each other, effectively meaning the gas is not
      * "stacking" and being refilled every time
      */
-    assert.ok(Math.abs(result.GasUsed - result2.GasUsed) < 600000)
+    assert.ok(Math.abs(result.GasUsed - result2.GasUsed) < 750000)
   })
 
   it('should run out of gas', async () => {
@@ -209,18 +209,18 @@ describe('loader', async () => {
 
   it('should handle Assignments', async () => {
     const handle = await AoLoader(wasmBinary, { format: 'wasm32-unknown-emscripten' })
-    
+
     // eslint-disable-next-line
     const result = await handle(null,
       { Owner: 'tom', Target: '1', Tags: [{ name: 'Action', value: 'Assignment' }], Data: '' },
       { Process: { Id: '1', Tags: [] } }
     )
 
     assert.deepStrictEqual(
-      result.Output, 
-      [ 
-        { Processes: [ 'pid-1', 'pid-2' ], Message: 'mid-1' },
-        { Processes: [ 'pid-1', 'pid-2' ], Message: 'mid-2' } 
+      result.Output,
+      [
+        { Processes: ['pid-1', 'pid-2'], Message: 'mid-1' },
+        { Processes: ['pid-1', 'pid-2'], Message: 'mid-2' }
       ]
     )