How to mount docker volume in Azure Web App for containers?

Question

I'm trying to run KrakenD image in Azure App Service.

KrakenD requires json config file krakend.json to be put into /etc/krakend/ (KrakenD image is based on Linux Alpine)

I created Web App for containers with the following docker-compose file:

version: "3"
services:
  krakend:
    image: devopsfaith/krakend:latest
    volumes:
      - ${WEBAPP_STORAGE_HOME}/site/krakend:/etc/krakend
    ports:
      - "8080:8080"
    restart: always

Added storage account with a blob container where uploaded sample kraken.json file

In app configuration i added a path mapping like this:

But it looks like volume was not mounted correctly

2019-11-15 12:46:29.368 ERROR - Container create failed for krakend_krakend_0_3032a936 with System.AggregateException, One or more errors occurred. (Docker API responded with status code=InternalServerError, response={"message":"invalid volume specification: ':/etc/krakend'"} ) (Docker API responded with status code=InternalServerError, response={"message":"invalid volume specification: ':/etc/krakend'"} ) InnerException: Docker.DotNet.DockerApiException, Docker API responded with status code=InternalServerError, response={"message":"invalid volume specification: ':/etc/krakend'"}

2019-11-15 12:46:29.369 ERROR - multi-container unit was not started successfully

Additional questions

1. What does mean Mount path in Storage mounting? - i put there value /krankend

2. volume definition starts with ${WEBAPP_STORAGE_HOME} in docs they specified it as

   volumes: - ${WEBAPP_STORAGE_HOME}/site/wwwroot:/var/www/html

so i did it by analogy and tried all 3 possible paths

${WEBAPP_STORAGE_HOME}/site/wwwroot/krakend
${WEBAPP_STORAGE_HOME}/site/krakend
${WEBAPP_STORAGE_HOME}/krakend

but no luck - still getting the error

ERROR parsing the configuration file: '/etc/krakend/krakend.json' (open): no such file or directory

Answer 1

finally resolved that with the following docker-compose file

version: "3"
services:
  krakend:
    image: devopsfaith/krakend:latest
    volumes:
      - volume1:/etc/krakend
    environment:
     WEBSITES_ENABLE_APP_SERVICE_STORAGE: TRUE
    ports:
      - "8080:8080"
    restart: always

where volume1 is a blob storage mounted as the following

Answer 2

This did not work for me. I was getting Bind mount must start with ${WEBAPP_STORAGE_HOME}.

This worked. docker-compose.yml

version: "3"
services:

  backend:
    image: xxxx
    ports:
      - 80:80
    volumes:
      - vol1:/var/www/html/public

volumes: 
   vol1:
      driver: local

Volume definition:

• Name: vol1
• Config: basic
• Storage accounts: ...
• Storage container: ...
• Mount paht: /var/www/html/public