Replace underscores with dashes while rendering container names

[achanda]

Kubernetes container names must match the regex a-z0-9?
This excludes underscores, which is common in container names in compose. Given this docker compose file

version: '2'
services:
  app:
    build: app
    container_name: forest_app
    image: app

Before this patch, compose generates this deployment

apiVersion: extensions/v1beta1
kind: Deployment
metadata:
  creationTimestamp: null
  name: app
spec:
  replicas: 1
  strategy: {}
  template:
    metadata:
      creationTimestamp: null
      labels:
        io.kompose.service: app
    spec:
      containers:
      - image: app
        name: forest_app
        resources: {}
      restartPolicy: Always
status: {}

After the patch, it generates

apiVersion: extensions/v1beta1
kind: Deployment
metadata:
  creationTimestamp: null
  name: app
spec:
  replicas: 1
  strategy: {}
  template:
    metadata:
      creationTimestamp: null
      labels:
        io.kompose.service: app
    spec:
      containers:
      - image: app
        name: forest-app
        resources: {}
      restartPolicy: Always
status: {}

The CLI output:

# ./kompose -f test.yaml convert
INFO Container name in docker-compose has been changed from "forest_app" to "forest-app"
WARN Kubernetes provider doesn't support build key - ignoring
INFO file "app-service.yaml" created
INFO file "app-deployment.yaml" created

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[achanda]

Signed!

[cdrage]

@achanda This looking great! Code LGTM 👍 💯

[achanda]

@cdrage I took the liberty of refactoring this so that we call the normalization code only once.

[surajssd]

nit: can we change the log to Container name in %q has been changed from %q to %q where the first %q being variable name this shows what service we have made change in!

[surajssd]

@achanda thanks for the PR, apart from that nit code LGTM!

[achanda]

@surajssd thanks, done!

[surajnarwade]

@achanda LGTM

[surajssd]

@achanda awesome!