I tried creating the Ruby Web App in Azure using the steps listed here It works great.

But, when I try creating a skeleton rails app using the following commands:

rails _5.1.2_ new sample_app

Add the following lines to application_controller.rb:

def hello
  render html: "Hello, world from Azure App Service on Linux!"
end

Add the following lines to config/routes.rb:

 root 'application#hello'

Now, when I push this code to Azure, I expect this to work just like the code in this repository. But, it does not work. (I get Service Unavailable error) What is the difference? In essence, what is the additional code that makes the code in this repository work? Any help would be appreciated.

Hi,
I am trying with a sample created by

rails new demo

while I push my changes the deployment starts but it would fail with this error:

Command: "/home/site/deployments/tools/deploy.sh"
ENOENT: no such file or directory, open '/opt/nodejs/12.13.0/npm.txt'
Handling node.js deployment.
Kudu sync from: '/home/site/repository' to: '/home/site/wwwroot'
Copying file: 't1.txt'
Ignoring: .git
Detecting node version spec...
Using default version: 12.13.0
Node.js versions available on the platform are: 4.4.7, 4.5.0, 4.8.0, 6.2.2, 6.6.0, 6.9.3, 6.10.3, 6.11.0, 6.17.1, 8.0.0, 8.1.4, 8.2.1, 8.8.1, 8.9.4, 8.11.2, 8.12.0, 8.15.1, 8.16.2, 9.4.0, 10.1.0, 10.10.0, 10.14.2, 10.17.0, 12.13.0.
Resolved to version 12.13.0
Detecting npm version spec...
An error has occurred during web site deployment.
select node version failed
ENOENT: no such file or directory, open '/opt/nodejs/12.13.0/npm.txt'\n/opt/Kudu/KuduConsole/Scripts/starter.sh "/home/site/deployments/tools/deploy.sh"

https://nokogiri.org/CHANGELOG.html#bug-fixes_4

[MRI] Fix regression in installation when building against system libraries, where some systems would not be able to find libxml2 or libxslt when present. (Regression introduced in v1.8.3.) [#1722]

Kudu is unable to install nokogiri 1.8.4

Please update nokogiri

rails/rails#35153

sqlite 1.4 has a compatibility issue with rails
please pin to 1.3.13