General improvements

.gitignore

@@ -1,3 +1,4 @@
 node_modules
 *.wasm
-dist
+dist
+.gocache

.vscode/tasks.json

@@ -0,0 +1,26 @@
+{
+    // See https://go.microsoft.com/fwlink/?LinkId=733558 
+    // for the documentation about the tasks.json format
+    "version": "2.0.0",
+    "tasks": [
+      {
+        "label": "build",
+        "type": "shell",
+        "command": "npm run build",
+        "problemMatcher": [
+          "$tsc"
+        ],
+        "group": {
+          "kind": "build",
+          "isDefault": true
+        },
+        "windows": {
+          "options": {
+            "shell": {
+              "executable": "powershell.exe"
+            }
+          }
+        }
+      }
+    ]
+}

README.md

@@ -67,15 +67,15 @@ import (
 	"github.com/aaronpowell/webpack-golang-wasm-async-loader/gobridge"
 )
 
-func add(i ...js.Value) js.Value {
+func add(i []js.Value) (interface{},error) {
 	ret := 0
 
 	for _, item := range i {
 		val, _ := strconv.Atoi(item.String())
 		ret += val
 	}
 
-	return js.ValueOf(ret)
+	return ret, nil
 }
 
 func main() {
@@ -96,9 +96,9 @@ To do this a function is exported from the package called `RegisterCallback` whi
 
 * A `string` representing the name to register it as in JavaScript (and what you'll call it using)
 * The `func` to register as a callback
-  * Note: The `func` must has a signature of `(args ...js.Value) js.Value` and you are responsible to box/unbox the JavaScript values to the appropriate Go types. Similarly you need to box the return type as a `js.Value`
+  * The `func` must has a signature of `(args js.Value) (interface{}, error)` so you can raise an error if you need
 
-If you want to register a static value that's been created from Go to be available in JavaScript you can do that with `RegisterValue`, which takes a name and a `js.Value`. Values are converted to functions that return a Promise so they can be treated asynchronously like function invocations.
+If you want to register a static value that's been created from Go to be available in JavaScript you can do that with `RegisterValue`, which takes a name and a value. Values are converted to functions that return a Promise so they can be treated asynchronously like function invocations.
 
 In JavaScript a global object is registered as `__gobridge__` which the registrations happen against.
 

ReleaseNotes.md

@@ -1 +1,3 @@
-Helps when your error handling is looking at the error argument to the callback...
+* Merged [PR #1](https://github.com/aaronpowell/webpack-golang-wasm-async-loader/pull/1) to update to Go 1.12
+* Added error handling support
+* Improved examples

azure-pipelines.pr.yml

@@ -0,0 +1,66 @@
+pr:
+  - master
+
+pool:
+  vmImage: 'Ubuntu-16.04'
+
+steps:
+- task: NodeTool@0
+  inputs:
+    versionSpec: '10.x'
+  displayName: 'Install Node.js'
+
+- script: |
+    npm install
+    npm run build
+  displayName: 'npm install and build'
+
+- script: |
+    npm pack
+  displayName: 'Package for npm release'
+
+- task: CopyFiles@2
+  inputs:
+    sourceFolder: '$(Build.SourcesDirectory)/dist'
+    contents: '**' 
+    targetFolder: $(Build.ArtifactStagingDirectory)/dist
+  displayName: 'Copy dist output'
+
+- task: PublishBuildArtifacts@1
+  inputs:
+    pathtoPublish: '$(Build.ArtifactStagingDirectory)/dist'
+    artifactName: dist
+  displayName: 'Publish dist files as artifacts'
+
+- task: CopyFiles@2
+  inputs:
+    sourceFolder: '$(Build.SourcesDirectory)'
+    contents: '*.tgz' 
+    targetFolder: $(Build.ArtifactStagingDirectory)/npm
+  displayName: 'Copy npm package'
+
+- task: CopyFiles@2
+  inputs:
+    sourceFolder: '$(Build.SourcesDirectory)'
+    contents: 'package.json' 
+    targetFolder: $(Build.ArtifactStagingDirectory)/npm
+  displayName: 'Copy package.json'
+
+- task: PublishBuildArtifacts@1
+  inputs:
+    pathtoPublish: '$(Build.ArtifactStagingDirectory)/npm'
+    artifactName: npm
+  displayName: 'Publish npm artifact'
+
+- task: CopyFiles@2
+  inputs:
+    sourceFolder: '$(Build.SourcesDirectory)'
+    contents: 'ReleaseNotes.md'
+    targetFolder: $(Build.ArtifactStagingDirectory)/release-notes
+  displayName: 'Copy Release Notes'
+
+- task: PublishBuildArtifacts@1
+  inputs:
+    pathtoPublish: '$(Build.ArtifactStagingDirectory)/release-notes'
+    artifactName: release-notes
+  displayName: 'Publish Release Notes artifact'

azure-pipelines.yml

@@ -1,5 +1,7 @@
 trigger:
-- master
+  branches:
+    include:
+      - master
 
 pool:
   vmImage: 'Ubuntu-16.04'

example/node/package.json

@@ -0,0 +1,18 @@
+{
+  "name": "golang-wasm-async-loader-example-nodejs",
+  "private": true,
+  "version": "1.0.0",
+  "description": "",
+  "main": "src/index.js",
+  "dependencies": {
+  },
+  "devDependencies": {
+  },
+  "scripts": {
+    "predemo": "GOOS=js GOARCH=wasm go build -o ./src/main.wasm ./src/main.go",
+    "demo": "node ./src/index.js"
+  },
+  "keywords": [],
+  "author": "",
+  "license": "MIT"
+}

example/node/src/index.js

@@ -0,0 +1,20 @@
+const gobridge = require('../../../dist/gobridge');
+const { join } = require('path');
+require('../../../lib/wasm_exec.js');
+require('isomorphic-fetch');
+const { readFileSync } = require('fs');
+
+global.requestAnimationFrame = global.setImmediate;
+
+let p = new Promise(resolve =>
+  resolve(readFileSync(join(__dirname, 'main.wasm')))
+);
+const wasm = gobridge.default(p);
+
+async function run() {
+  let result = await wasm.add(1,2);
+
+  console.log(result);
+};
+
+run();

example/node/src/main.go

@@ -0,0 +1,38 @@
+//+ build js,wasm
+
+package main
+
+import (
+	"errors"
+	"strconv"
+	"syscall/js"
+
+	"../../../gobridge"
+)
+
+var global = js.Global()
+
+func add(this js.Value, args []js.Value) (interface{}, error) {
+	ret := 0
+
+	for _, item := range args {
+		val, _ := strconv.Atoi(item.String())
+		ret += val
+	}
+
+	return ret, nil
+}
+
+func err(this js.Value, args []js.Value) (interface{}, error) {
+	return nil, errors.New("This is an error")
+}
+
+func main() {
+	c := make(chan struct{}, 0)
+	println("Web Assembly is ready")
+	gobridge.RegisterCallback("add", add)
+	gobridge.RegisterCallback("raiseError", err)
+	gobridge.RegisterValue("someValue", "Hello World")
+
+	<-c
+}