Skip to main content

azure-functions

Creating Azure Functions​

  • Linux is limited feature of development lifecycle
  • Window is fully support
  • Azure Function docker doesn't support arm like Macbook M1

Getting Started​

func init LocalFunctionProj --typescript

ข้อควรระวัง​

ในหนึ่ง function จะมี 1 export หรือ 1 default export เท่านั้น !!!!!

Minimal Project Structure​

Example:

.
├── HttpTrigger1
│   ├── function.json
│   └── index.ts
├── host.json
├── local.settings.json
├── package.json
└── tsconfig.json

1 directory, 6 files

ใน file HttpTrigger1/index.ts ต้องมี 1 Export หรือ default export เท่านั้น

ไม่งั้นมันจะ Error แบบนี้

Worker was unable to load function <FunctionName>: 'Unable to determine function entry point. If multiple functions are exported, you must indicate the entry point, either by naming it 'run' or 'index', or by naming it explicitly via the 'entryPoint' metadata property.'

ตัวอย่างที่ทำให้ Error

import { AzureFunction, Context, HttpRequest } from "@azure/functions"

// Don't export here !! ตรงนี้จะทำให้ Error
export const config = 'hello';

const httpTrigger: AzureFunction = async function (context: Context, req: HttpRequest): Promise<void> {};

export default httpTrigger;

Function.json​

HTTP Type (anonymous)​

{
    "bindings": [
        {
            "authLevel": "anonymous",
            "type": "httpTrigger",
            "direction": "in",
            "name": "req",
            "methods": [
                "get",
                "post"
            ]
        },
        {
            "type": "http",
            "direction": "out",
            "name": "res"
        }
    ],
    "scriptFile": "../dist/HttpExample/index.js"
}

Storage Account Setting​

File: local.settings.json

Required Fields:

  • FUNCTIONS_WORKER_RUNTIME need to be node
  • AzureWebJobsStorage need to config for following triggers:
    • httptrigger, kafkatrigger, rabbitmqtrigger, orchestrationTrigger, activityTrigger, entityTrigger
{
    "IsEncrypted": false,
    "Values": {
      "FUNCTIONS_WORKER_RUNTIME": "node",
      "AzureWebJobsStorage": "UseDevelopmentStorage=true"
    }
  }

Using Local Storage Account: Need to install Azurite for local development

{
    "AzureWebJobsStorage": "UseDevelopmentStorage=true"
}

Using Storage Account on Azure

{
    "AzureWebJobsStorage": "DefaultEndpointsProtocol=https;AccountName=MyAccName;AccountKey=XXXXXXX==;EndpointSuffix=core.windows.net"
}

Resources​

Examples​

Thoubleshooting​

Error: "Value cannot be null. (Parameter 'provider')" when run func start​

{
  "version": "2.0",
  "logging": {
    "applicationInsights": {
      "samplingSettings": {
        "isEnabled": true,
        "excludedTypes": "Request"
      }
    }
  },
   "extensionBundle": {
     "id": "Microsoft.Azure.Functions.ExtensionBundle",
     "version": "[2.*, 3.0.0)"
  }
}

Don't forget to run

func extensions install

Ref: Install all extensions - Offcial Azure Docs

Worker was unable to load entry point "xxxxx": Found zero files matching the supplied pattern​

please make sure main in package.json is existing file.

I've found the error from Azure/azure-functions-nodejs-worker

But I don't know how the main entrypoint file working.

Local Dev​

Enable streaming logs​

# Only Windows-based Azure Function
func azure functionapp logstream <FunctionAppName>

Live Metrics Stream​

func azure functionapp logstream <FunctionAppName> --browser

Download App Setting From Azure Function​

func azure functionapp fetch-app-settings <functionAppName>
Missing value for AzureWebJobsStorage in local.settings.json. This is required for all triggers other than httptrigger, kafkatrigger, rabbitmqtrigger, orchestrationTrigger, activityTrigger, entityTrigger. You can run 'func azure functionapp fetch-app-settings <functionAppName>', specify a connection string in local.settings.json, or use managed identity to authenticate.