Change resource.limits.cpus conversion to string

[SMFloris]

Fixed the regression introduced in 1.27.0, by changing the resource.limits.cpus conversion to string in order to be compatible with docker stack deploy.

Steps to reproduce the issue:

Having the following docker-compose.yml file

version: '3.7'

services:
    api:
        image: busybox
        command: ['sleep', '10']
        deploy:
            resources:
                limits:
                    cpus: '1'

>#running the following from versions 1.27.0 to 1.28.0dev gives an error
>docker-compose -f docker-compose.yml config | docker stack deploy
services.api.deploy.resources.limits.cpus must be a string

After the fix, the command runs as expected.

Resolves #7774

[SMFloris]

I also noticed by diffing the json schema from docker-compose with the config schema used by docker stack deploy (https://github.com/docker/cli/blob/master/cli/compose/schema/data/config_schema_v3.9.json) that the resource.reservations.cpus values are also supposed to be strings so I changed the interpolation of those as well.

This is the first time I'm browsing through docker stack/docker-compose code, but is there any reason why there are two configs at all? Wouldn't it be safer/easier to have one primary config and one that extends the other in some way?

EDIT: in order to reproduce, use the following docker-compose.yml file:

version: '3.7'

services:
    api:
        image: busybox
        command: ['sleep', '10']
        deploy:
            resources:
                reservations:
                    cpus: 1

>#running the following from versions 1.27.0 to 1.28.0dev gives an error
>docker-compose -f docker-compose.yml config | docker stack deploy
services.api.deploy.resources.reservations.cpus must be a string

[ulyssessouza]

Already fixed by #7768

[gingerhot]

Already fixed by #7768

@ulyssessouza I don't think so, please see #7774 carefully

[champ]

@ulyssessouza please consider reopening this issue,

As @gingerhot indicates with the issue #7774 although the schema supports strings again for deploy.resources.limits.cpus, docker-compose config is not consistent with the schema outputting a number if the original value is a string. This breaks compatibility with docker stack deploy.
However, docker-compose config works as expected for deploy.resources.reservations.cpus, conserving string values.

[ieugen]

I also have issues with this.

version: "3.9"
service:
....
      resources:
        limits:
          memory: 5g
          cpus: "4.0"
        reservations:
          memory: 3g
          cpus: "2.0"

 ./deploy.sh 
Generating .env file
Configuring stack compose file
Deploying dev stack
services.classifier.deploy.resources.limits.cpus must be a string

cat deploy.sh

#! /bin/bash
set -e

echo "Generating .env file"
cp .env.default .env
[ -f .env.dev ] && cat .env.dev >> .env

echo "Configuring stack compose file"
docker-compose --file stack.yml --env-file .env config > .stack.yml

echo "Deploying dev stack"
docker stack deploy --compose-file .stack.yml dev

cat .stack.yml

      resources:
        limits:
          cpus: 4.0
          memory: 5g
        reservations:
          cpus: '2.0'
          memory: 3g

[brunocascio]

Hi guys, I'm facing the same issue with cpus limits.

It's not related to reservations, It's related to limits.

as @ieugen mentioned above.

Is there any workaround without a hacky solution? I'm using compose version 1.29.2