Render error of a variable with the colon, space and asterisk symbol

[johnbizokk]

Description

When we are trying to parametrize the template with the variable, the value of which contains the colon, space (one or more), and asterisk symbol in a row - docker app binary produces a render error. The problem doesn't appear when we do not add the space between the colon and the asterisk symbols.

I also attached the working examples - see the Annex №4,5,6 below.

Steps to reproduce the issue:

1. Have the docker-compose file with the following content - see the Annex №1 below.
2. Have the parameters.yml file with the following content - see the Annex №2 below.
3. Have the metadata.yml file with the following content - see the Annex №3 below.
4. Execute the following render command - docker app render.

Describe the results you received:

Unfortunately, we've got the following error:
render failed: Action "com.docker.app.render" failed: yaml: did not find expected alphabetic or numeric character

Describe the results you expected:

We are expecting from the docker app binary to render the template correctly.

Output of docker version:

Client: Docker Engine - Community
 Version:           19.03.5
 API version:       1.40
 Go version:        go1.12.12
 Git commit:        633a0ea
 Built:             Wed Nov 13 07:22:37 2019
 OS/Arch:           windows/amd64
 Experimental:      true

Server: Docker Engine - Community
 Engine:
  Version:          19.03.5
  API version:      1.40 (minimum version 1.12)
  Go version:       go1.12.12
  Git commit:       633a0ea
  Built:            Wed Nov 13 07:29:19 2019
  OS/Arch:          linux/amd64
  Experimental:     true
 containerd:
  Version:          v1.2.10
  GitCommit:        b34a5c8af56e510852c35414db4c1f4fa6172339
 runc:
  Version:          1.0.0-rc8+dev
  GitCommit:        3e425f80a8c931f88e6d94a8c831b9d5aa481657
 docker-init:
  Version:          0.18.0
  GitCommit:        fec3683

Output of docker-app version:

Version:               v0.8.0
Git commit:            7eea32b7
Built:                 Wed Nov 13 07:39:54 2019
OS/Arch:               windows/amd64
Experimental:          off
Renderers:             none
Invocation Base Image: docker/cnab-app-base:v0.8.0

Output of docker info:

Client:
 Debug Mode: false
 Plugins:
  app: Docker Application (Docker Inc., v0.8.0)
  buildx: Build with BuildKit (Docker Inc., v0.3.1-tp-docker)

Server:
 Containers: XX
  Running: XX
  Paused: XX
  Stopped: XX
 Images: XX
 Server Version: 19.03.5
 Storage Driver: overlay2
  Backing Filesystem: tmpfs
  Supports d_type: true
  Native Overlay Diff: true
 Logging Driver: local
 Cgroup Driver: cgroupfs
 Plugins:
  Volume: local
  Network: bridge host ipvlan macvlan null overlay
  Log: awslogs fluentd gcplogs gelf journald json-file local logentries splunk syslog
 Swarm: inactive
 Runtimes: runc
 Default Runtime: runc
 Init Binary: docker-init
 containerd version: b34a5c8af56e510852c35414db4c1f4fa6172339
 runc version: 3e425f80a8c931f88e6d94a8c831b9d5aa481657
 init version: fec3683
 Security Options:
  seccomp
   Profile: default
 Kernel Version: 4.19.76-linuxkit
 Operating System: Docker Desktop
 OSType: linux
 Architecture: x86_64
 CPUs: XX
 Total Memory: XX.XGiB
 Name: docker-desktop
 ID: XXXX
 Docker Root Dir: /var/lib/docker
 Debug Mode: false
 Registry: https://index.docker.io/v1/
 Labels:
 Experimental: true
 Insecure Registries:
  127.0.0.0/8
 Live Restore Enabled: false
 Product License: Community Engine

Annex №1 (docker-compose.yml) - render error - group №1

version: '3.8'
services:
  application:
    x-enabled: "${enable-application}"
    image: "image"
    deploy:
      labels:
        traefik.frontend.headers.customResponseHeaders: "${application.headers}"

Annex №2 (parameters.yml) - render error - group №1

enable-application: true
application:
  headers: 'Access-Control-Allow-Origin: *'

Annex №3 (metadata.yml) - render error - group №1

version: 1.0.0
name: application
description: "application bundle"
namespace: "namespace"
maintainers:
  - name: Maintainer
    email: "email@mail.com"

Annex №4 (docker-compose.yml) - successful render - group №2

version: '3.8'
services:
  application:
    x-enabled: "${enable-application}"
    image: "image"
    deploy:
      labels:
        traefik.frontend.headers.customResponseHeaders: "${application.headers}"

Annex №5 (parameters.yml) - successful render - group №2

enable-application: true
application:
  headers: 'Access-Control-Allow-Origin:*'

Annex №6 (metadata.yml) - successful render - group №2

version: 1.0.0
name: application
description: "application bundle"
namespace: "namespace"
maintainers:
  - name: Maintainer
    email: "email@mail.com"