How to replace json file in release in VSTS CD?

Question

While deploying a build to multiple environments like UAT, Production. I want to replace one file config.uat.json or config.prod.json with config.json. Is there any option available? just like we have XML Transformation.

I am aware of Json Variable substitution but that doesn't serve my purpose as the variable list is long (almost 50 entries)

Thanks in Advance!

Why do you think Json Variable substitution doesn't serve your purpose? — Cece Dong - MSFT, Jul 05 '18 at 08:24
Thanks for your response and sorry for late reply. Json variable subsition won't be a good solution since the list is very long and a frequent update is required — Saurabh Dhingra, Jul 24 '18 at 19:35

score 2 · Answer 1 · answered Jul 05 '18 at 08:34

JSON variable substitution should be a good option, if you don't want to add variables one by one on Variables tab, you can update them with VSTS REST API, or add a powershell script to set the variables.

Otherwise, you may need to delete the config.uat.json or config.prod.json, and copy the config.json to the target machine.

Didier Aupest · Accepted Answer · 2018-07-24T20:23:57.220

Inside your Program.cs file, you can get an environment variable which will represent your current environment:

var builder = WebHost.CreateDefaultBuilder(args);
var currentEnv = builder.GetSetting("environnement");

using this currentEnv value, you will be able to load the file config.{currentEnv}.json

builder.AddJsonFile($"config.{currentEnv}.json", optional: false, reloadOnChange: true);

EDIT:

If you want to do this in powershell, you can make a transofmration of your configuration file with a default: appsettings.json containing keys, and appsettings.env.json containing overriding.

To transform your configuration, you can do something like this:

Param(
   [Parameter(Mandatory=$true)][string]$SpecificConfig
)
$defaultConfig = "AppSettings.json";
$settingsContent = ConvertFrom-Json $defaultConfig;
$specificContent = ConvertFrom-Json $SpecificConfig;

# Do this on each <property> to override
if (![string]::IsNullOrEmpty($specificContent.<property>))
{
    $settingsContent.<property> = $specificContent.<property>;
}
Write-Host $settingsContent > $defaultConfig;

One of the solutions I thought of if quite similar. I was wondering if there is a way we can do json transformation just like xml transformation — Saurabh Dhingra, Jul 24 '18 at 19:38
You can, but as far as I know, there is no built-in tool to do this properly. In powershell, you can load your AppSettings.json with ConvertFrom-Json $file. An Edit will be made to complete the answer. — Didier Aupest, Jul 24 '18 at 20:16

How to replace json file in release in VSTS CD?

2 Answers2