Change variables in appsettings when deploying with github actions

Question

I am trying to deploy an app with github actions. I linked my azure account to my github repository and the following actions has been created:

name: Build and deploy ASP.Net Core app to Azure Web App - my_app_name

on:
  push:
    branches:
      - master

jobs:
  build-and-deploy:
    runs-on: ubuntu-latest

    steps:
    - uses: actions/checkout@master

    - name: Set up .NET Core
      uses: actions/setup-dotnet@v1
      with:
        dotnet-version: '3.1.102'

    - name: Build with dotnet
      run: dotnet build --configuration Release

    - name: dotnet publish
      run: dotnet publish -c Release -o ${{env.DOTNET_ROOT}}/myapp

    - name: Deploy to Azure Web App
      uses: azure/webapps-deploy@v1
      with:
        app-name: 'my_app_name'
        slot-name: 'production'
        publish-profile: ${{ secrets.AzureAppService_PublishProfile_xxxxxx }}
        package: ${{env.DOTNET_ROOT}}/myapp 

I have some variables in my appsettings.json file that I want to overwrite, but I don't find how to do it.

Answer 1

You may add the following action prior to deploying the artifacts to azure.

You can specify multiple files and it is supported with wildcard entries too.

The environment variable key must be specified with dot separated heirarchy.

#substitute production appsettings entries to appsettings json file
- name: App Settings Variable Substitution
  uses: microsoft/variable-substitution@v1
  with:
    files: '${{env.DOTNET_ROOT}}/myapp/appsettings.json'
  env:
    ConnectionStrings.Default: ${{ secrets.some_connection_string }}
    App.ServerRootAddress: ${{ env.SERVER_ROOT_ADDRESS }}

The above action can be used for xml and yaml file changes too.