packer-push bug input

packer.json

{ "variables": {
    "amznrepo" : "file:///var/repo",
    "version" : "1.0",
    "repository" : "nexstra/createrepo",
    "baseImage" : "amazonlinux:latest",
    "yumrepo"  : "",
    "amznrepo" : "/space/amazonlinux/repo",
    "yumrepod"  : "{{pwd}}/../yum.repos.d",
    "awsEcr" : "{{env `AWS_ECR`}}",
    "doEcrLogin" : "true"
  },
  "builders" : [
  {
    "type": "docker",
    "image":"{{user `baseImage`}}",
    "commit" : true ,
    "volumes" : {  
       "{{user `amznrepo`}}/amzn-main" : "/var/repo/amzn-main",
       "{{user `amznrepo`}}/amzn-updates" : "/var/repo/amzn-updates",
       "{{user `yumrepo`}}" : "/var/repo/nexstra",
       "{{user `yumrepod`}}" : "/etc/yum.repos.d"
    },
    "run_command" : [
        "-d" , "-i" , "-t" , 
        "--entrypoint", "/bin/bash" ,
        "{{.Image}}" ],
    "changes" : [ 
      "WORKDIR /tmp",
      "CMD [ \"createrepo\", \"/rpms\"]",
      "LABEL  project=createrepo version={{user `version`}} from={{user `baseImage`}}",
      "VOLUME /rpms"

    ]

  }],
  "provisioners" : [
   {
    "type":"shell",
    "inline" : [ 
        "yum -y install createrepo yum-utils",
        "mkdir /rpms",
        "true"
          ],
    "environment_vars": [ 
        "_AMZN_REPO={{user `amznrepo`}}" 
     ]
   }
  ],
  "post-processors": [ 
   { 
       "type" : "docker-tag" ,
       "repository" : "{{user `repository`}}",
       "tag" : "{{user `version`}}"
  },
     { 
         "type" : "docker-tag" ,
         "repository" : "{{user `awsEcr`}}/{{user `repository`}}",
         "tag" : "{{user `version`}}"
    },
     { 
      "type": "docker-push" ,
      "login_email" : "{{user `email`}}",
      "aws_access_key" : "{{user `awsaccesskey`}}",
      "aws_secret_key" : "{{user `awssecretkey`}}",
      "ecr_login" : "{{user `doEcrLogin`}}",
      "login_server" : "https://{{user `awsEcr`}}/"
     },
   {
     "type" : "manifest",
     "output": "linux-manifest.json"
   } 
   ]
}