[
https://issues.apache.org/jira/browse/HBASE-26192?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Andrew Kyle Purtell reassigned HBASE-26192:
-------------------------------------------
Assignee: Andrew Kyle Purtell
> hbck.jsp should provide a JSON formatted output option
> ------------------------------------------------------
>
> Key: HBASE-26192
> URL: https://issues.apache.org/jira/browse/HBASE-26192
> Project: HBase
> Issue Type: New Feature
> Reporter: Andrew Kyle Purtell
> Assignee: Andrew Kyle Purtell
> Priority: Minor
> Fix For: 2.5.0, 3.0.0-alpha-2, 2.6.0
>
>
> It used to be possible to get hbck's verdict of cluster status from the
> command line, especially useful for headless deployments, i.e. without
> requiring a browser with sufficient connectivity to load a UI, or scrape
> information out of raw HTML, or write regex to comb over log4j output. The
> hbck tool's output wasn't particularly convenient to parse but it was
> straightforward to extract the desired information with a handful of regular
> expressions.
> HBCK2 has a different design philosophy than the old hbck, which is to serve
> as a collection of small and discrete recovery and repair functions, rather
> than attempt to be a universal repair tool. This makes a lot of sense and
> isn't the issue at hand. Unfortunately the old hbck's utility for reporting
> the current cluster health assessment has not been replaced either in whole
> or in part. Instead:
> {quote}
> HBCK2 is for fixes. For listings of inconsistencies or blockages in the
> running cluster, you go elsewhere, to the logs and UI of the running cluster
> Master. Once an issue has been identified, you use the HBCK2 tool to ask the
> Master to effect fixes or to skip-over bad state. Asking the Master to make
> the fixes rather than try and effect the repair locally in a fix-it tool's
> context is another important difference between HBCK2 and hbck1.
> {quote}
> Developing custom tooling to mine logs and scrape UI simply to gain a top
> level assessment of system health is unsatisfying. There should be a
> convenient means for querying the system if issues that rise to the level of
> _inconsistency_, in the hbck parlance, are believed to be present. It would
> be relatively simple to bring back the experience of invoking a command line
> tool to deliver a verdict. This could be added to the hbck2 tool itself but
> given that hbase-operator-tools is a separate project an intrinsic solution
> is desirable.
> An option that immediately comes to mind is modification of the Master's
> hbck.jsp page to provide a JSON formatted output option if the HTTP Accept
> header asks for text/json. However, looking at the source of hbck.jsp, it
> makes more sense to leave it as is and implement a convenient machine
> parseable output format elsewhere. This can be trivially accomplished with a
> new servlet. Like hbck.jsp the servlet implementation would get a reference
> to HbckChore and present the information this class makes available via its
> various getters.
> The machine parseable output is sufficient to enable headless hbck status
> checking but it still would be nice if we could provide operators a command
> line tool that formats the information for convenient viewing in a terminal.
> That part could be implemented in the hbck2 tool after this proposal is
> implemented.
--
This message was sent by Atlassian Jira
(v8.20.1#820001)
