Bug description
When trying to create a stack which uses an explicit IPv6 address in ports, portainer responds with an error.
Using an IPv4 address instead works fine.

docker-compose supports both IPv4 and IPv6 syntax and starts the docker-proxy with the specified configuration derived from ports.

Expected behavior
Portainer creates stack successfully.

Portainer Logs
The Portainer container logs:

level=error msg="Could not parse config for project alpinetest : Service 'alpine' configuration key 0 value Does not match format 'ports'"
<date + time> http error: Service 'alpine' configuration key 0 value Does not match format 'ports' (err=Service 'alpine' configuration key 0 value Does not match format 'ports') (code=500)

The Portainer WebUI displays the following error:
Deployment error Service 'alpine' configuration key 0 value Does not match format 'ports'

Browser console shows:

POST https://localhost:9000/api/stacks?endpointId=2&method=string&type=2 500
(anonymous) @ vendor.d14bda68403d46ff0e35.js:formatted:32543
(anonymous) @ vendor.d14bda68403d46ff0e35.js:formatted:32358
(anonymous) @ vendor.d14bda68403d46ff0e35.js:formatted:32398
(anonymous) @ vendor.d14bda68403d46ff0e35.js:formatted:34759
(anonymous) @ vendor.d14bda68403d46ff0e35.js:formatted:34765
$eval @ vendor.d14bda68403d46ff0e35.js:formatted:35192
$digest @ vendor.d14bda68403d46ff0e35.js:formatted:35117
$apply @ vendor.d14bda68403d46ff0e35.js:formatted:35219
(anonymous) @ vendor.d14bda68403d46ff0e35.js:formatted:37068
dispatch @ vendor.d14bda68403d46ff0e35.js:formatted:5008
g.handle @ vendor.d14bda68403d46ff0e35.js:formatted:4946

Steps to reproduce the issue:

1. Go to 'Stacks'
2. Click on '+ add stack'
3. Enter a name, e.g. 'alpineTest'
4. Enter the below compose file into the web editor

version: 2
services:
  alpine:
    ports:
    - "2001:db8::1:80:80/tcp"
    image: alpine:latest
    network_mode: bridge

replacing - "2001:db8::1:80:80/tcp" with - "192.0.2.1:80:80/tcp" results in a successful deployment. Both versions result in a successful deployment when using docker-compose.

Technical details:

• Portainer version: 1.23.0
• Docker version (managed by Portainer): 19.03.5
• Docker Compose version: 1.24.1 (used to verify docker compose file syntax and functionality)
• Platform (windows/linux): linux
• Browser: Chrome 79