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https://issues.apache.org/jira/browse/COUCHDB-2037?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13882159#comment-13882159
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Jason Smith commented on COUCHDB-2037:
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Interestingly, CouchDB already has that view data available, even when you
replace the design document. You must explicitly do a view cleanup to remove
those files from disk:
http://docs.couchdb.org/en/latest/api/database/compact.html?highlight=cleanup#post--db-_view_cleanup
So this implementation is not as difficult as it may seem.
A very quick and dirty fix could be a hidden or obscure URL where you could
query a view directly by its hash value (the MD5 of the ddoc.views value, i.e.
the name of the file on disk with the .view suffix), and couch could just trust
that you know what you are talking about and attempt to query that file.
Standard "thinking aloud" disclaimer applies :)
> view unavailability on production design docs
> ---------------------------------------------
>
> Key: COUCHDB-2037
> URL: https://issues.apache.org/jira/browse/COUCHDB-2037
> Project: CouchDB
> Issue Type: New Feature
> Components: JavaScript View Server
> Reporter: Isaac Z. Schlueter
>
> It can take a very long time to generate views for a large database. If you
> have an application that relies on those views, even if performance is
> acceptable, it is generally a serious problem if something causes the views
> for that design doc to no longer be available. This gets especially tricky
> if a new view is added or modified, as then all view data is thrown away and
> regenerated, causing your website or app to be unavailable for hours at a
> time.
> To work around this problem, I've taken to the following work flow:
> 1. PUT the new design doc to /db/_design/scratch
> 2. Load a view from /db/_design/scratch
> 3. Once view generation on _design/scratch finishes, send an http COPY
> request to move the _design/scratch to _design/app.
> This mostly works pretty well. However, if you have jobs that copy couchdb
> documents from one place to another, it can be very easy to accidentally
> trigger a view regeneration and cause your website or app to go down. (Qv
> today's npmjs.org outage.)
> I would love it if there was a way to say, "NEVER make the views of
> _design/app unavailable, even if they are temporarily out of date". I can
> imagine a few ways that this could be accomplished:
> 1. PUTs to the specified design doc fail if they modify the "views" member.
> 2. COPYs to the specified design doc fail if the COPY source does not have a
> full set of pre-generated views.
> 3. Views for the specified design doc are always done in the background, and
> stale=ok is assumed for all requests.
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