Azure functions isolated host findings and adding appsettings.json for configuration.

  1. Starting worker process failed, the operation has timed out : Visual studio hasn’t caught up with the function tooling yet, to overcome this issue, install the func cli and run the the command func start, if you are comfortable with VSCODE, you will be at home.
  2. There are lot of great articles out there on how to get started with the azure isolated host functions, but the most complete one that i found is the post Azure Functions and .NET 5: Dependency Injection – DEV Community by Kenichiro Nakamura – DEV Community
  3. There is no documentation out there at least from what I found on how to add configuration Ex: appsettings.json to the isolated functions project. So lets see how we can add this feature.
    1. Add an appsettings file to the root folder and change the file properties to copy
    2. Update the Program.cs class to include the following
  public static void Main()
            var host = new HostBuilder()
                .ConfigureAppConfiguration(e =>
                    e.AddJsonFile("appsettings.json", optional: false, reloadOnChange: true).AddEnvironmentVariables().Build()
                .ConfigureServices(services =>

3. Update the Function with the following

  public class ConfigurationTest
        private readonly DomainFacade _domainFacade;
        private readonly IConfiguration _configuration;

        public ConfigurationTest(DomainFacade domainFacade, IConfiguration configuration)
            _domainFacade = domainFacade;
            _configuration = configuration;

        public async Task Run([TimerTrigger("0 */1 * * * *")] FunctionContext context)
            var logger = context.GetLogger("Function1");
            logger.LogInformation($"C# Timer trigger function executed at: {DateTime.Now}" + _configuration["CosmosDb:AccountPrimaryKey"]);

            await _domainFacade.DomainMethod(string someValue );

4. And this will work locally as well as on the cloud, without tinkering with the path of the appsettings, the example is for a timetrigger function, but this will work for any trigger.


Pagination in cosmos db

the following code snippet details on how to do pagination is cosmos db , we just need to pass a pagesize and the continuation token, when we are calling the method for the first time, we can just pass in a null and for the subsequent requests, we can pass in the continuation token, which is returned as a part of the response of this method.

 public async Task<ProductResponse> GetAllProducts(int pageSize, string continuationToken)
            List<Product> products = new List<Product>();
            ProductsResponse productsResponse = new ProductsResponse();
            QueryDefinition queryDef = new QueryDefinition("select * from Prodcuts p");
            string token = null;
            if (!string.IsNullOrWhiteSpace(continuationToken))
                token = continuationToken;

            using FeedIterator<Product> resultSet = _container.GetItemQueryIterator<Product>(queryDefinition: queryDef, continuationToken: token, new QueryRequestOptions { MaxItemCount = pageSize });
                var items = await resultSet.ReadNextAsync();
                foreach (Product item in items)

  productsResponse.ContinuationToken = items.ContinuationToken;

            productResponse.Products = products;
            return productResponse;

Azure Bicep template for Azure Cosmos DB serverless

Azure Cosmos DB serverless went GA last week, but the documentation has not caught up yet, if you are looking to provision an Azure Cosmos DB serverless account using Bicep you can use the following snippet, the magic here is the capabilities section.

resource cosmos 'Microsoft.DocumentDB/databaseAccounts@2021-04-15' = {
  name: cosmosName
  location: location
  kind: 'GlobalDocumentDB'
  properties: {
    //enableFreeTier: true
    consistencyPolicy: {
      defaultConsistencyLevel: 'Session'
    locations: [
        locationName: location
        failoverPriority: 0
        isZoneRedundant: false
    capabilities: [
        name: 'EnableServerless'
    databaseAccountOfferType: 'Standard'

Handling azure data bricks errors in azure datafactory

issue: when an exception happens in azure datafactory notebooks only just a url contianing the details is sent back to the datafactory, it does not go to the error flow.

one of the solutions we implemented was to catch an exception in the notebook is to send a json string containing the following



“ExceptionDetails”:”some exception happend”


then datafactory will parse the json object log it if it wants and then choose the appropriate flow to handle the exception.

if you want to terminate the pipeline then do something like the following, where in use dynamic sql to raise an error.

azure data factory 2 – How do I raise an error from if activity in ADFV2? – Stack Overflow

hope this helps..

Http wrapper for Terraform CLI Part 1

OOB Hashicorp doesn’t offer an Terraform HTTP API/SDK for provisioning resources to cloud providers using terrafrom templates,(Their proprietary cloud does an awesome job of doing this).

However on the other hand Azure and AWS have an API (SDK) for provisioning resources using ARM and cloud formation templates.

For this POC i went ahead and created a wrapper for the terraform CLI to create an resource group in Azure.

The wrapper is written in Azure C# functions running locally, the second post of this series will cover the same functions running in Azure (hopefully).

The steps that i took are as follows

  1. Installed AZURE CLI and logged in.
  2. Created a Azure Functions Project
  3. Copied the terraform template, and the terraform cli into windows temp folder (C:\Users\<<username>>\AppData\Local\Temp)
  4. And the code is below and self explanatory, used the StartProcess method (and i did something similar Invoke Btstask from .net code – madhukar gilla ( in Dec 2010)
terraform {
  required_providers {
    azurerm = {
      source = "hashicorp/azurerm"
      version = "~>2.0"
provider "azurerm" {
  features {}

resource "azurerm_resource_group" "myterraformgroup" {
    name     = "myResourceGroup"
    location = "eastus"

    tags = {
        environment = "Terraform Demo"
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.IO;
using System.Net.Http;
using System.Threading.Tasks;
using Microsoft.Azure.WebJobs;
using Microsoft.Azure.WebJobs.Extensions.DurableTask;
using Microsoft.Azure.WebJobs.Extensions.Http;
using Microsoft.Extensions.Logging;
using Newtonsoft.Json;

namespace TerraformHttpWrapper
    public static class Function2
        public static async Task<List<string>> RunOrchestrator(
            [OrchestrationTrigger] IDurableOrchestrationContext context)
            var outputs = new List<string>();

            // Replace "hello" with the name of your Durable Activity Function.
            outputs.Add(await context.CallActivityAsync<string>("Function2_Hello", "Tokyo"));
            //outputs.Add(await context.CallActivityAsync<string>("Function2_Hello", "Seattle"));
            //outputs.Add(await context.CallActivityAsync<string>("Function2_Hello", "London"));

            // returns ["Hello Tokyo!", "Hello Seattle!", "Hello London!"]
            return outputs;

        public static string SayHello([ActivityTrigger] string name, ILogger log, ExecutionContext context)
            log.LogInformation($"Saying hello to {name}.");

            log.LogInformation("C# HTTP trigger function processed a request.");

            var tempRootDir = Path.GetTempPath();


            log.LogInformation($"----------------------------- Current directory { Directory.GetCurrentDirectory()} --------------------");
                Process p = new Process();
                p.StartInfo.UseShellExecute = false;
                p.StartInfo.FileName = "terraform.exe";
                p.StartInfo.Arguments = "init";
                p.StartInfo.RedirectStandardOutput = true;

                log.LogInformation("*****************************" + Environment.CurrentDirectory);


                log.LogInformation("----------------------------- DONE init --------------------");

                Process ptwo = new Process();
                ptwo.StartInfo.UseShellExecute = false;
                ptwo.StartInfo.FileName = "terraform.exe";
                ptwo.StartInfo.Arguments = "plan  -detailed-exitcode -lock=false";
                ptwo.StartInfo.RedirectStandardOutput = true;


                log.LogInformation("----------------------------- DONE plan --------------------");

                Process pthree = new Process();
                pthree.StartInfo.UseShellExecute = false;
                pthree.StartInfo.FileName = "terraform.exe";
                pthree.StartInfo.Arguments = "apply -auto-approve -lock=false";
                pthree.StartInfo.RedirectStandardOutput = true;



                log.LogInformation("----------------------------- DONE apply --------------------");

            catch (Exception ed)
                log.LogInformation("Error: ." + ed);

            return name;

        public static async Task<HttpResponseMessage> HttpStart(
            [HttpTrigger(AuthorizationLevel.Anonymous, "get", "post")] HttpRequestMessage req,
            [DurableClient] IDurableOrchestrationClient starter,
            ILogger log)
            // Function input comes from the request content.
            string instanceId = await starter.StartNewAsync("Function2", null);

            log.LogInformation($"Started orchestration with ID = '{instanceId}'.");

            return starter.CreateCheckStatusResponse(req, instanceId);

And the logs from the Azure Function and terraform cli are as follows.

Terrafrom and Azure Functions logs

And the created function group

ffmpeg, my favourite tool for audio editing.

As you know based on my previous posts that i recently bought a fitbit ionic for inbuilt GPS and music player, i have been using playerfm on mobile forever, one of the nice features of palyerfm is to increase/decrease the audio speed, and i am habituated to listening at 1.2x speed, now without these option in the native ionic music player, i had to fallback on editing the podcasts on my machine by using ffmpeg.

All you have to do is run the following cmd, use the atempo parameter to adjust the speed accordingly.

ffmpeg -i input.mp3 -filter:a “atempo=1.2” -vn output.mp3

its all worth it because i don’t have to carry my mobile phone for those long walks or jogs !!

Fitbit Ionic initial setup and firmware update…

Recently bought an Fitbit ionic, reason being

  1. I don’t need to carry a phone or another device for music and GPS.

the initial setup was a bummer thought of returning it back, the only way I could update the firmware was doing the following

  1.  Have 3g on the phone.
  2. Make the phone a hotspot
  3. Install the Fitbit app on Mac or windows(blue tooth).
  4. Add a new device and run the setup through the computer.
  5. Configure Fitbit WiFi to use to the Mobile Hotspot from step 2.
  6. And on the update configuration screen just select activity tracking, leave the others they will get automatically installed.

That’s it.. well then what combination did not work.

  1. With the app on windows configuring the Fitbit WiFi to use  Hotel/Home/Office WiFi did not work all were 2.4 GHz.
  2. Tried the same setup above with a phone instead of an windows box did not work.
  3. Tried both the above steps with Bluetooth instead of WiFi did not work.

Alll the best and post comments for any other information or questions.