[METRON-1529] CONFIG_GET Fails to Retrieve Latest Config When Run in Zeppelin REPL

• Type: Bug
• Status: Done
• Priority: Minor
• Resolution: Done
• Fix Version/s: 0.5.0
• Assignee: Nick Allen
• Reporter: Nick Allen
• Created: 18/Apr/18 15:01
• Updated: 22/May/18 19:34
• Resolved: 12/May/18 19:33

Description

The configuration values retrieve by CONFIG_GET are incorrect when run in the Zeppelin REPL. The cache backing CONFIG_GET retrieves the correct value when the function is initialized. If the value is changed either in the same session or by an external process, the cache is never updated to the latest value. Restarting the Zeppelin REPL session and forcing reinitialization will cause the correct, latest value to be retrieved.

Do the following in a Zeppelin Notebook to replicate the bug.

1. Follow the README to install the Stellar Zeppelin Interpreter.

2. In Zeppelin > Interpreters > Stellar, set the zookeeper URL property.

    zookeeper.url = localhost:2181
    

3. In Zeppelin > Interpreters > Stellar, set the following additional dependencies.

artifact	exclude
org.apache.metron:metron-management:0.4.3
org.apache.metron:metron-common:0.4.3
io.thekraken:grok:0.1.0	org.apache.commons:commons-lang3
org.apache.commons:commons-lang3:3.2

4. Create a notebook and run the following.

CONFIG_GET("GLOBAL")
{
  "k6" : "v6"
}

CONFIG_PUT("GLOBAL",  '{ "k7":"v7" }')

CONFIG_GET("GLOBAL")
{
  "k6" : "v6"
}

5. The last result shold be "k7"/"v7", but is instead the old value "k6"/"v6".

Issue Links

• supercedes: METRON-1512 Refactor CONFIG_GET/CONFIG_PUT to Use ZKConfigurationsCache
• links to: GitHub Pull Request #997