September 2014 - BaseX-Talk - mailman.uni-konstanz.de

What is the best way to implement an async REST method?
by Marc van Grootel 16 Dec '14

16 Dec '14

How would you implement an async REST pattern? I don't remember having seen anything that makes me do this using plain XQuery. Does this mean the only way to tackle this would be via Java and events maybe? I would post to a URL, this URL would accept the post and return a temporary URL where I can check the status of my request, then once it's ready this temp URL will redirect me to the location of the real resource. That's the gist of the async REST pattern that I would like to implement. What would be the best approach to experiment with this? --Marc

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REST queries: "Read permissions needed"
by Jérôme Chauveau 25 Nov '14

25 Nov '14

Hi, i am using BaseX79 as a webapp - embedded in a tomcat7 server. I am working on a php application which runs REST xqueries to my BaseX server. I created a "mydb" database and a user "myuser". Then i granted READ permissions for "myuser". > *GRANT read TO myuser* > *GRAND read TO myuser ON mydb* > *show users* Username Read Write Create Admin ------------------------------------ admin X X X X myuser X > *show users on mydb* Username Read Write --------------------- myuser X All my REST xqueries returns a "READ permission needed." message with the user "myuser" when its works properly with the admin user account. Moreover, REST xqueries via a web browser (logged as 'myuser') works properly too. Did i miss something? Thank's for help. Jérôme. -- Jérôme Chauveau - SAIC-CERTIC - Campus 4 Université de Caen Basse-Normandie

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Full text score with or
by Andy Bunce 23 Nov '14

23 Nov '14

Hi, I want to score searches with multiple conditions e.g. let $data:=( <r><a>red apple</a></r>, <r><a>blue lagoon</a></r>, <r><b>fish and chips</b></r>) for $hit score $s in $data[ a contains text("red") or b contains text("fish")] return $s In 7.8.2 it always returns scores of zero. In version 7.6 it returns numbers like 0.6201145069582775 0.4528324252639413 Is this bug? Regards /Andy

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stream binary responses from http:module
by Johan Mörén 10 Nov '14

10 Nov '14

Hi I have built a small client in XQuery that fetches zip files from another remote service using the http-module and stores them on disk with the help of the file-module. Some of the returned zip files are really large and BaseX seems to need to materialize the files in memory before writing them to disk resulting in out of memory errors for some files. Is there some way read the response in a more streamable fashion when using the http-module? I tried using the fetch:binary function successfully but i really need the more extended functionality of the http-module. #results in out of memory if the zip file is too large file:write-binary("file.zip", http:sendrequest(...)[2]) #works all the time. file:write-binary("file.zip", fetch:binary(...)) Regards, Johan

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IllegalMonitorStateException
by Gerald de Jong 07 Oct '14

07 Oct '14

Dear BaseX experts, I'm wondering if anybody can see something that I'm doing wrong. I would expect it to be possible to add documents from multiple threads. Am I wrong about that?? When I set two of my datasets saving documents to BaseX 7.9 at the same time, I get this exception: $ basexserver BaseX 7.9 [Server] Server was started (port: 1984) Exception in thread "Thread-2295" java.lang.IllegalMonitorStateException at java.util.concurrent.locks.ReentrantReadWriteLock$Sync.tryRelease(ReentrantReadWriteLock.java:374) at java.util.concurrent.locks.AbstractQueuedSynchronizer.release(AbstractQueuedSynchronizer.java:1260) at java.util.concurrent.locks.ReentrantReadWriteLock$WriteLock.unlock(ReentrantReadWriteLock.java:1131) at org.basex.core.DBLocking.release(DBLocking.java:219) at org.basex.core.Context.unregister(Context.java:249) at org.basex.core.Command.execute(Command.java:104) at org.basex.core.Command.execute(Command.java:117) at org.basex.server.ClientListener.execute(ClientListener.java:384) at org.basex.server.ClientListener.add(ClientListener.java:355) at org.basex.server.ClientListener.run(ClientListener.java:100) All I am doing is making concurrent calls in two parallel sessions: session = new ClientSession(...) session.execute(new Open(database)) session.execute(new Set("autoflush", "false")) session.add([path string], [document-bytes]) // a zillion times session.execute(new Flush()) During the execution of the parallel add commands, it crashes. The relevant code: def withSession[T](block: ClientSession => T): T = { val session = new ClientSession(host, port, user, pass) try { block(session) } finally { session.close() } } def withDbSession[T](database: String)(block: ClientSession => T): T = { withSession { session => session.execute(new Open(database)) session.execute(new Set("autoflush", "false")) val result = block(session) session.execute(new Flush()) result } } then: withDbSession { session => // many calls to session.add(...) } -- Delving BV, Vasteland 8, Rotterdam http://www.delving.eu http://twitter.com/fluxe skype: beautifulcode +31629339805

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Eclipse vs BaseX Gui differences ?
by jean-marc Mercier 06 Oct '14

06 Oct '14

Hi all, Happy to write again in this mailing-list, hope you are all doing well guys ! I am encountering a small problem running my old xquery modules. I guess that it is a classical issue, but I can't remember how to look into BaseX archive :( Here is the description of the problem : I am running a query, calling module_of_mine.xqm, on two different environments. The first one is eclipse, linked to the latest interpreter from BaseX80-20140923.183154 (but I tested also against older interpreter). In this way, this query saturated my 12 G Java machine after some minutes. Then I installed module_of_mine.xqm into BaseX repo, and ran the same query using basex gui with 4G heap size. The query ran perfectly in some 30 sec. My first penny guess is that the built-in BaseX xquery profiler is doing some nice work there ? If so, is there a way to activate / desactivate this profiler from eclipse or from some configuration files ? Cheers, Jean-Marc

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deduplication problem in BaseX 7.9?
by C. M. Sperberg-McQueen 06 Oct '14

06 Oct '14

Consider the following XML document: <article> <front> <article-meta> <aff id="aff1">Tropical and Infectious Disease Hospital, Kathmandu, Nepal</aff> <aff id="aff2">Nagasaki University, Nagasaki, Japan</aff> <aff id="aff3">Department of Radiology, Kyorin University Faculty of Medicine, Tokyo, Japan</aff> <aff id="aff5">Pentax Company Limited, Tokyo, Japan</aff> <aff id="aff6">National Research Laboratory of Molecular Complex Control, Yonsei University, Seoul, Korea</aff>  <article-id pub-id-type="pmc">2570825</article-id> <article-id pub-id-type="pmid">18325280</article-id> <article-id pub-id-type="publisher-id">07-0473</article-id> <article-id pub-id-type="doi">10.3201/eid1403.070473</article-id> </article-meta> </front>  </article For convenience in trying to understand this problem, a copy of this document has been placed at [1]. When I issue the following search against this document, I get unexpected results. let $doc := doc('http://blackmesatech.com/2014/LIS590DML/data/testdata.xml') let $path1 := $doc/child::article/child::front /child::article-meta /child::aff[contains(.,"Japan")] /parent::article-meta/child::article-id, $path2 := $doc/descendant::aff[contains(.,"Japan")] /parent::article-meta/child::article-id, $path3 := $doc/article/front/article-meta/aff[contains(.,'Japan')] /../article-id, $path4 := $doc//aff[contains(.,'Japan')]/../article-id, $path5 := $doc//aff/../article-id return (count($path1), count($path2), count($path3), count($path4), count($path5)) What I expect is that path1, path2, path3, path4, and path5 should all return the same results, namely the set of four article-id elements in the document. So the sequence of counts returned should be 4 4 4 4 4. What I am finding is that path1 and path3 are returning 12 results, with each article-id present three times in the result (once, apparently, for every aff element containing the string 'Japan'). Paths 2, 4, and 5 are all returning 4 results each, as I had expected them to. So the sequence of counts actually returned is 12 4 12 4 4. In BaseX 7.6, for what it's worth, this query returns the sequence 12 12 12 12 20, which seems suggestive. Interestingly, if I initialize the variable $doc with a direct element constructor, along the lines of let $doc := document { <article>...</article> } then all counts come out as expected in 7.6, but in 7.9 the result continues to be 12 4 12 4 4. Is this an error in the handling of the / operator, or am I missing some subtle point? Many thanks. [1] http://blackmesatech.com/2014/LIS590DML/data/testdata.xml -- **************************************************************** * C. M. Sperberg-McQueen, Black Mesa Technologies LLC * http://www.blackmesatech.com * http://cmsmcq.com/mib * http://balisage.net ****************************************************************

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how generating wiki from Basex inspect:xqdoc ?
by jean-marc Mercier 06 Oct '14

06 Oct '14

Hi all, I am using BaseX' inspect:xqdoc module to generate xquery docs. I was wondering how generating html pages for accessing this documentation from the web, as for instance Leo did for http://www.woerteler.de/xquery/modules/base64 ?? Thanx cheers, Jean-Marc

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Hierarchy of databases
by Vincent Vandeghinste 30 Sep '14

30 Sep '14

We have set up a system in which we have about 17 million BaseX databases, but my operating system does not allow 17 million subdirectories in one directory ( the one set in the .basex file). In order to resolve this, we had to set up four (4) BaseX servers on four different machines so we could resolve this. Depending on the name of the BaseX database, we know on which BaseX server we have to look. As this is a work around, it would be nice to have either the possibility to have a hierarchy of databases, so we can store them into more manageable directories, or to allow to run more than one BaseX server onto a single machine (for instance, listening on different ports). For more info on the reasons why we did this: Vandeghinste and Augustinus (2014). Making Large Treebanks Searchable. The SONAR case. In Marc Kupietz, Hanno Biber, Harald Lüngen, Piotr Bański, Evelyn Breiteneder, Karlheinz Mörth, Andreas Witt, Jani Takhsha (eds.), Proceedings of the 2nd workshop on Challenges in the management of large corpora (CMLC-2) at the Ninth International Conference on Language Resources and Evaluation (LREC). Reykjavik, Iceland. pp. 15-20. Is there another way to solve this? thanks, v.

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Changing the C# BasexClient.cs
by Nilanjan Dutta 30 Sep '14

30 Sep '14

Hi All, I want to change/overload the implementation private void Send (Stream s) method in the BaseXClient.cs file. [ basex <https://github.com/BaseXdb/basex> / basex-api <https://github.com/BaseXdb/basex/tree/master/basex-api> / src <https://github.com/BaseXdb/basex/tree/master/basex-api/src> / main <https://github.com/BaseXdb/basex/tree/master/basex-api/src/main> / c# <https://github.com/BaseXdb/basex/tree/master/basex-api/src/main/c%23> / *BaseXClient.cs*] *Existing implementation:* private void Send(Stream s) { while (true) { int t = s.ReadByte(); if (t == -1) break; if (t == 0x00 || t == 0xFF) stream.WriteByte(Convert.ToByte(0xFF )); stream.WriteByte(Convert.ToByte(t)); } stream.WriteByte(0); info = Receive(); if(!Ok()) { throw new IOException(info); } } *What I want it to be:* [image: Inline image 1] This one is faster for my use case. Please do let me know how can this be done? Regards, N.D.

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