Windows 10 bind mounts in docker-compose not working - windows

Question

I'm using docker-compose to manage a multi container application. 1 of those containers needs access to the contents of a directory on the host.
This seems simple according to the various sources of documentation on docker and docker-compose but I'm struggling to get it working.
event_processor:
environment:
- COMPOSE_CONVERT_WINDOWS_PATHS=1
build: ./Docker/event_processor
ports:
- "15672:15672"
entrypoint: python -u /src/event_processor/event_processor.py
networks:
- app_network
volumes:
- C/path/to/interesting/directory:/interesting_directory"
Running this I get the error message:
ERROR: Named volume
"C/path/to/interesting/directory:/interesting_directory:rw" is used in
service "event_processor" but no declaration was found in the
volumes section.
I understand from the docs that a top level declaration is only necessary if data is to be shared between containers
which isn't the case here.
The docs for docker-compose I linked above have an example which seems to do exactly what I need:
version: "3.2"
services:
web:
image: nginx:alpine
ports:
- "80:80"
volumes:
- type: volume
source: mydata
target: /data
volume:
nocopy: true
- type: bind
source: ./static
target: /opt/app/static
networks:
webnet:
volumes:
mydata:
However when I try, I get errors about the syntax:
ERROR: The Compose file '.\docker-compose.yaml' is invalid because:
services.audio_event_processor.volumes contains an invalid type, it
should be a string
So I tried to play along:
volumes:
- type: "bind"
source: "C/path/to/interesting/directory"
target: "/interesting_directory"
ERROR: The Compose file '.\docker-compose.yaml' is invalid because:
services.audio_event_processor.volumes contains an invalid type, it should be a string
So again the same error.
I tried the following too:
volumes:
- type=bind, source=C/path/to/interesting/directory,destination=/interesting_directory
No error, but attaching to the running container, I see the following two folders;
type=bind, source=C
So it seems that I am able to create a number of volumes with 1 string (though the forward slashes are cutting the string in this case) but I am not mapping it to the host directory.
I've read the docs but I think I'm missing something.
Can someone post an example of mounting a a windows directory from a host to a linux container so that the existing contents of the windows dir is available from the container?

Answer 1

OK so there were multiple issues here:
1.
I had
version: '3'
at the top of my docker-compose.yml. The long syntax described here wasn't implemented until 3.4 so I stopped receiving the bizarre syntax error when I updated this to:
version: '3.6'
2.
I use my my docker account on 2 windows PCs. Following a hint from another stackoverflow post, I reset Docker to the factory settings. I had to give docker the computer username and password with the notice that this was necessary to access the contents of the local filesystem - at this point I remembered doing this on another PC so I'm not sure whether the credentials were correct on this on. With the correct credentials for the current PC, I was able to bind-mount the volume with the expected results as follows:
version: '3.6'
event_processor:
environment:
- COMPOSE_CONVERT_WINDOWS_PATHS=1
build: ./Docker/event_processor
ports:
- "15672:15672"
entrypoint: python -u /src/event_processor/event_processor.py
networks:
- app_network
volumes:
- type: bind
source: c:/path/to/interesting/directory
target: /interesting_directory
Now it works as expected. I'm not sure if it was the factory reset or the updated credentials that fixed it. I'll find out tomorrow when I use another PC and update.