[
https://issues.apache.org/jira/browse/SOLR-725?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12625326#action_12625326
]
Noble Paul commented on SOLR-725:
---------------------------------
bq.What we do is after we make the necessary changes do a reload.
We just blindly do a reload assuming everything is fine. So no testing.
bq.Correct, this is another useful way of using aliases to achieve the same.
This does not look like a useful way of using aliases. This is one extra step
which could have been avoided
According to me the *alias* feature is implemented in a very wrong way.Because
of that some commonly used methods have no consistency SolrCore#getName(),
CoreDescriptor#getName() etc .
Moreover I am yet to see a valid usecase. I just wonder why it is there
> CoreContainer/CoreDescriptor/SolrCore cleansing
> -----------------------------------------------
>
> Key: SOLR-725
> URL: https://issues.apache.org/jira/browse/SOLR-725
> Project: Solr
> Issue Type: Improvement
> Affects Versions: 1.3
> Reporter: Henri Biestro
> Attachments: solr-725.patch
>
>
> These 3 classes and the name vs alias handling are somewhat confusing.
> The recent SOLR-647 & SOLR-716 have created a bit of a flux.
> This issue attemps to clarify the model and the list of operations.
> h3. CoreDescriptor: describes the parameters of a SolrCore
> h4. Definitions
> * has one name
> ** The CoreDescriptor name may represent multiple aliases; in that
> case, first alias is the SolrCore name
> * has one instance directory location
> * has one config & schema name
> h4. Operations
> The class is only a parameter passing facility
> h3. SolrCore: manages a Lucene index
> h4. Definitions
> * has one unique *name* (in the CoreContainer)
> ** the *name* is used in JMX to identify the core
> * has one current set of *aliases*
> ** the name is the first alias
> h4. Name & alias operations
> * *get name/aliases*: obvious
> * *alias*: adds an alias to this SolrCore
> * *unalias*: removes an alias from this SolrCore
> * *name*: sets the SolrCore name
> ** potentially impacts JMX registration
> * *rename*: picks a new name from the SolrCore aliases
> ** triggered when alias name is already in use
> h3. CoreContainer: manages all relations between cores & descriptors
> h4. Definitions
> * has a set of aliases (each of them pointing to one core)
> ** ensure alias uniqueness.
> h4. SolrCore instance operations
> * *load*: makes a SolrCore available for requests
> ** creates a SolrCore
> ** registers all SolrCore aliases in the aliases set
> ** (load = create + register)
> * *unload*: removes a core idenitified by one of its aliases
> ** stops handling the Lucene index
> ** all SolrCore aliases are removed
> * *reload*: recreate the core identified by one of its aliases
> * *create*: create a core from a CoreDescriptor
> ** readies up the Lucene index
> * *register*: registers all aliases of a SolrCore
>
> h4. SolrCore alias operations
> * *swap*: swaps 2 aliases
> ** method: swap
> * *alias*: creates 1 alias for a core, potentially unaliasing a
> previously used alias
> ** The SolrCore name being an alias, this operation might trigger
> a SolrCore rename
> * *unalias*: removes 1 alias for a core
> ** The SolrCore name being an alias, this operation might trigger
> a SolrCore rename
>
--
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.
