[AMBARI-11202] templeton.hive.properties property value substitution should be done by ambari-server

• Type: Bug
• Status: Resolved
• Priority: Critical
• Resolution: Fixed
• Affects Version/s: 2.1.0
• Fix Version/s: 2.1.0
• Component/s: ambari-server
• Labels: kerberos kerberos_descriptor
• Assignee: Robert Levas
• Reporter: Robert Levas
• Created: 17/May/15 22:33
• Updated: 20/May/15 19:12
• Resolved: 20/May/15 17:32

Description

The webhcat-site/templeton.hive.properties property value substitution should be done by ambari-server. This value is more complicated than others since the (embedded) hive.metastore.uris property is a list of thrift URIs generated using the set of hosts the Hive Metastore is installed on. This list of hosts comes from the clusterHostInfo/hive_metastore_host value, which in the KerberosHelper (org.apache.ambari.server.controller.KerberosHelper) is available as a comma-delimited list of hosts.

clusterHostInfo/hive_metastore_host = "host1,host2,host3"

To generate configuration values when enabling Kerberos, the KerberosHelper class uses org.apache.ambari.server.state.kerberos.AbstractKerberosDescriptor#replaceVariables to replace variables specified in the Kerberos Descriptor. Currently this mechanism uses a simple replacement scheme, which is not sufficient to generate string using a delimited list of values.

In order to solve this issue, "functions" need to be applied to replacement data before making the substitution. In this case a "function" named "each" will be created that takes the following arguments:

• pattern with placeholders
• delimiter to use to concatenate values generated using the patter
• regex to use to split the original string

For example:

function declaration, commas are escaped when not intended to separate function args

each(thrift://%s:9083, \\,, \s*\,\s*)

To indicate this function is to be used, the following Kerberos Descriptor variable replacement syntax is to be used:

${clusterHostInfo/hive_metastore_host|each(thrift://%s:9083, \\,, \s*\,\s*)}

Note: \ characters need to be escaped in JSON structure values. For example:

"some.property" : "${clusterHostInfo/hive_metastore_host|each(thrift://%s:9083, \\\\,, \\s*\\,\\s*)}"

If clusterHostInfo/hive_metastore_host = "host1,host2,host3", the result would be

thrift://host1:9083\,thrift://host2:9083\,thrift://host3:9083

Issue Links

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