[
https://issues.apache.org/jira/browse/CAMEL-26646?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Claus Ibsen updated CAMEL-26646:
--------------------------------
Fix Version/s: 4.24.0
4.22.3
4.18.6
> camel-couchdb - maxMessagesPerPoll 0 or negative, documented as unlimited, is
> sent as the CouchDB _changes limit
> ----------------------------------------------------------------------------------------------------------------
>
> Key: CAMEL-26646
> URL: https://issues.apache.org/jira/browse/CAMEL-26646
> Project: Camel
> Issue Type: Bug
> Components: camel-couchdb
> Affects Versions: 4.18.5, 4.22.2, 4.23.0
> Reporter: Federico Mariani
> Assignee: Jiří Ondrušek
> Priority: Major
> Fix For: 4.18.6, 4.22.3, 4.24.0
>
>
> h3. Problem
> The couchdb consumer documents {{maxMessagesPerPoll}} as "The default value
> is 10. Use 0 or a negative number to set it as unlimited"
> ({{components/camel-couchdb/src/main/java/org/apache/camel/component/couchdb/CouchDbEndpoint.java}}
> lines 296-303 on main, commit 7978db3d42dd, and the catalog/component docs).
> The value is never checked for 0 or a negative number. It is passed straight
> to CouchDB as the {{limit}} of the {{_changes}} request
> ({{CouchDbClientWrapper.java}} lines 92-99, called from
> {{CouchDbConsumer.java}} line 78):
> {code:java}
> PostChangesOptions postChangesOptions = new PostChangesOptions.Builder()
> .db(dbName)
> .since(since)
> .limit(maxMessagesPerPoll)
> .build();
> {code}
> The Cloudant SDK (0.10.22) adds the {{limit}} query parameter whenever it is
> set. CouchDB does not treat 0 or a negative limit as "no limit":
> * *0*: CouchDB returns no changes. The consumer never moves {{since}}, so
> every poll is empty forever. Nothing is logged, and the route looks healthy.
> * *negative*: CouchDB answers HTTP 400 {{bad_request: The limit value should
> be a non-negative integer}}, so every poll fails.
> h3. How to reproduce
> Measured against CouchDB 3.5.3 ({{mirror.gcr.io/couchdb:3.5.3}}, the
> test-infra image). The test creates the consumer of
> {{couchdb:http://<host>:<port>/<db>?username=admin&password=...&createDatabase=true&maxMessagesPerPoll=<n>}},
> which reads the latest update sequence of the database. It then saves five
> documents with the couchdb producer and calls {{CouchDbConsumer.poll()}} once:
> ||maxMessagesPerPoll||poll() result||
> |10 (default, control)|5 changes|
> |0|0 changes, although 5 are waiting|
> |-1|{{com.ibm.cloud.sdk.core.service.exception.BadRequestException:
> bad_request: The limit value should be a non-negative integer}}|
> The same holds for plain {{POST /db/_changes}} on a database with 12
> documents. {{limit=0}} gives 0 results and {{limit=-1}} / {{limit=-5}} give
> HTTP 400. {{limit=3}} gives 3, and no {{limit}} gives 12. The CouchDB
> documentation of {{_changes}} does not say what 0 or a negative limit does;
> the numbers above are what the server returned.
> h3. Proposed change
> * In {{CouchDbClientWrapper.pollChanges}}, call {{.limit(...)}} only when
> {{maxMessagesPerPoll > 0}}. With 0 or a negative value, the request then has
> no limit, which is the documented "unlimited". All the changes since the last
> {{since}} come back in one response and are processed in that poll.
> * Add a unit test with a mocked {{Cloudant}} client that captures the
> {{PostChangesOptions}}: {{limit()}} must be null for 0 and -1, and 10 by
> default.
> * Optional cleanup: the Javadoc of {{setMaxMessagesPerPoll}} repeats its
> first sentence twice (this text is also the catalog description).
> h3. Impact / upgrade
> * The default (10) does not change, and nothing changes for positive values.
> No upgrade-guide entry is needed: 0 and negative values change from "nothing
> is ever received" / "every poll fails" to the documented behaviour.
> * Only the consumer is affected; the producer does not use the option.
> * The Camel code is the same on camel-4.18.x, camel-4.22.x and main, and in
> the released 4.7.0, 4.18.5, 4.22.2 and 4.23.0 tags, so this is a backport
> candidate for both LTS branches. The server reproduction was run on main only.
> h3. Related
> * Introduced in 4.7.0 by CAMEL-20800 (commit 77b58e811ead, "Use cloudant
> instead of LightCouch"). That commit added {{maxMessagesPerPoll}} together
> with this Javadoc; before it, the component had no such option.
> * CAMEL-25290 (PR #27322): an earlier fix in the same {{poll()}} (skipped
> changes did not move {{since}}).
> * CAMEL-26224 (PR #29067): the latest couchdb change; it does not touch this
> path.
> _Claude Code on behalf of Federico Mariani_
--
This message was sent by Atlassian Jira
(v10.3.26#10030026)
