[AMBARI-6624] Make validation for minimum required number of service components from cardinality field of stacks API

• Type: Task
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.7.0
• Fix Version/s: 1.7.0
• Component/s: ambari-web
• Assignee: Antonenko Alexander
• Reporter: Antonenko Alexander
• Created: 25/Jul/14 18:58
• Updated: 28/Jul/14 12:28
• Resolved: 28/Jul/14 12:28

Description

web-ui imposes validation for minimum limit of host components required to be installed for a service. Right now it is 1 for all master components except ZK server and HBase Master. So on "Assign Master" page UI doesn't show "+" sign next to any service component except ZK server and HBase master.

For now for Slave components, the minimum limit is 1 and maximum limit is "ALL". So If user does not select any host, web-ui throws validation error asking user to atleast select one host.

As a resolution to this ticket, this validation logic needs to be fetched from the server. Stacks API has cardinality field

{
  "href" : "http://c6401.ambari.apache.org:8080/api/v1/stacks/HDP/versions/2.1/stackServices/HDFS/components?fields=StackServiceComponents/cardinality",
  "items" : [
    {
      "href" : "http://c6401.ambari.apache.org:8080/api/v1/stacks/HDP/versions/2.1/services/HDFS/components/DATANODE",
      "StackServiceComponents" : {
        "cardinality" : "1+",
        "component_name" : "DATANODE",
        "service_name" : "HDFS",
        "stack_name" : "HDP",
        "stack_version" : "2.1"
      }
    },
    {
      "href" : "http://c6401.ambari.apache.org:8080/api/v1/stacks/HDP/versions/2.1/services/HDFS/components/HDFS_CLIENT",
      "StackServiceComponents" : {
        "cardinality" : "0+",
        "component_name" : "HDFS_CLIENT",
        "service_name" : "HDFS",
        "stack_name" : "HDP",
        "stack_version" : "2.1"
      }
    },
    {
      "href" : "http://c6401.ambari.apache.org:8080/api/v1/stacks/HDP/versions/2.1/services/HDFS/components/JOURNALNODE",
      "StackServiceComponents" : {
        "cardinality" : "0+",
        "component_name" : "JOURNALNODE",
        "service_name" : "HDFS",
        "stack_name" : "HDP",
        "stack_version" : "2.1"
      }
    },
    {
      "href" : "http://c6401.ambari.apache.org:8080/api/v1/stacks/HDP/versions/2.1/services/HDFS/components/NAMENODE",
      "StackServiceComponents" : {
        "cardinality" : "1",
        "component_name" : "NAMENODE",
        "service_name" : "HDFS",
        "stack_name" : "HDP",
        "stack_version" : "2.1"
      }
    },
    {
      "href" : "http://c6401.ambari.apache.org:8080/api/v1/stacks/HDP/versions/2.1/services/HDFS/components/SECONDARY_NAMENODE",
      "StackServiceComponents" : {
        "cardinality" : "1",
        "component_name" : "SECONDARY_NAMENODE",
        "service_name" : "HDFS",
        "stack_name" : "HDP",
        "stack_version" : "2.1"
      }
    },
    {
      "href" : "http://c6401.ambari.apache.org:8080/api/v1/stacks/HDP/versions/2.1/services/HDFS/components/ZKFC",
      "StackServiceComponents" : {
        "cardinality" : "0+",
        "component_name" : "ZKFC",
        "service_name" : "HDFS",
        "stack_name" : "HDP",
        "stack_version" : "2.1"
      }
    }
  ]
}

cardinality can also have value "ALL" which means service component should be installed on all hosts of the cluster

{
  "href" : "http://c6401.ambari.apache.org:8080/api/v1/stacks/HDP/versions/2.1/services/GANGLIA/components/GANGLIA_MONITOR?fields=StackServiceComponents/cardinality",
  "StackServiceComponents" : {
    "cardinality" : "ALL",
    "component_name" : "GANGLIA_MONITOR",
    "service_name" : "GANGLIA",
    "stack_name" : "HDP",
    "stack_version" : "2.1"
  }
}

We should not require hard-coded map in App.StackServiceComponent.cardinality function once this ticket is resolved