February 2013 - BaseX-Talk - mailman.uni-konstanz.de

JSON or JSONML output formatting
by Zachary Pride 16 Jul '14

16 Jul '14

Hello, I've been playing with BaseX lately and all-in-all am very impressed. Something I'm wrestling with however is the JSON output options. I've got various web applications that would really be simplified by receiving JSON straight away for the obvious scripting benefits. The JSON method has been giving me a lot of grief, stipulating rules I'm not sure how to follow. right now I have an element that "is typed as string and cannot be nested." I've been able to get JSONML to output but the JSON is this morass of nested Arrays... Attributes seem to get transformed into Objects but elements/tags and their values are pushed into Arrays for some rationale - which I suppose is on purpose. My question is how can I get Objects for simple key:value properties from <tag>value</tag> 's. Are there options I'm not utilizing? Would it be feasible to transform the XML output to some middle form first - setting it up to become Objects, before serializing it to JSON? Thanks! Zach Pride Associate Software Engineer Ultra Electronics, ProLogic 1000 Green River Drive, Ste. 201 Fairmont, WV 26554 zachary.pride(a)ultra-prologic.com Tel: +1 304 333 2680 ext.308 www.ultra-prologic.com This e-mail from Ultra Electronics, ProLogic and any attachments to it are confidential to the intended recipient and may also be privileged or controlled by U.S. export control laws and regulations. No technical data, information or other items provided by Ultra Electronics, ProLogic in connection with this email shall be shared or provided to any foreign persons, entities, or subsidiaries without the expressed written authorization of Ultra Electronic, ProLogic. If you have received it in error please notify the sender and delete it from your system. If you are not the intended recipient you must not copy it or use it for any purpose nor disclose or distribute its contents to any other person. All communications may be subject to interception or monitoring for operational and/or security purposes. Please rely on your own virus checking as the sender cannot accept any liability for any damage arising from any bug or virus infection. This e-mail from Ultra Electronics, ProLogic and any attachments to it are confidential to the intended recipient and may also be privileged or controlled by U.S. export control laws and regulations. No technical data, information or other items provided by Ultra Electronics, ProLogic in connection with this email shall be shared or provided to any foreign persons, entities, or subsidiaries without the expressed written authorization of Ultra Electronic, ProLogic. If you have received it in error please notify the sender and delete it from your system. If you are not the intended recipient you must not copy it or use it for any purpose nor disclose or distribute its contents to any other person. All communications may be subject to interception or monitoring for operational and/or security purposes. Please rely on your own virus checking as the sender cannot accept any liability for any damage arising from any bug or virus infection. Please consider the environment before printing this email.

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Out of memory bug
by Ivan Lagunov 31 Jul '13

31 Jul '13

Hello, I've got 'Out of memory' error and corrupted database again, this time it's for 6.3 version. Steps: 1. Started server, started terminal client, checked there are no text and attribute indexes. 2. Started my Java application that runs several tests on database: querying, adding, removing. 3. Then I forgot to reopen terminal client and used the one that I opened in Step 1. 4. Run optimize command for the collection and got error. 5. Cannot open the collection any more as I'm getting 'Out of memory'. It's clear that I shouldn't have used the terminal client that I opened before execution of my Java application. But sometimes it's hard to remember. And it's completely unacceptable that these actions result in the corrupted database. You really should catch ArrayIndexOutOfBoundsException everywhere in order to save database from being corrupted. Terminal client stacktrace: > optimize Possible bug? Feedback is welcome: basex-talk(a)mailman.uni-konstanz.de BaseX 6.3: java.lang.ArrayIndexOutOfBoundsException: -1 org.basex.data.PathSummary.add(PathSummary.java:68) org.basex.core.cmd.Optimize.stats(Optimize.java:68) org.basex.core.cmd.Optimize.run(Optimize.java:34) org.basex.core.Command.run(Command.java:236) org.basex.core.Command.exec(Command.java:218) org.basex.core.Command.execute(Command.java:66) org.basex.server.ServerProcess.run(ServerProcess.java:161) > open products Out of Main Memory. Best regards, Ivan

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indent parameter
by Hans-Juergen Rennau 28 Jun '13

28 Jun '13

Hello, it seems to me there is a couple of issues concerning the handling of indentation (serialization parameter "indent"). a) Using "indent=no" whitespace-only text nodes between element nodes are removed b) Using "indent=yes" the content of elements with xml:space="preserve" is indented, too I suppose both behaviors are in contraction to the spec ( http://www.w3.org/TR/xslt-xquery-serialization/#xml-indent ). As a particular consequence, (a) seems to preclude making an exact copy of a document (fragment) - all whitespace-only text nodes vanish. And as a consequence of (b) one has no possibility to locally protect the whitespace used in the source document, as required for example when reusing "programlisting" elements of docbook. Or did I overlook something? Kind regards, Hans-Juergen

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Best practices for concurrency
by The Trainspotter 19 Jun '13

19 Jun '13

Hi, I've read through the online example on server concurrency, however, currently I'm not running a BaseXServer instance I'm just running things locally. I want multiple threads in my application to be able to query the database at once without treading on each others toes. What's the best approach for doing this? I have tried querying the database using different threads but I keep getting internal BaseX errors which leads me to think I'm going about this the wrong way. Cheers Gary

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invalid collection name?
by C. M. Sperberg-McQueen 27 May '13

27 May '13

Using the GUI interface to BaseX 7.2, when I select Database / Open and Manage ..., I get a list of the databases I have built over the time I've been using BaseX. When I try to open the collection named MEP.bigbooks, though, I get an error box saying "Name 'MEP.bigbooks' is invalid." In the "Manage Databases" dialog box, the information about the collection appears normal and plausible (at least, the size is about what I expect, and so on). It's only when I try to open the collection that I run into the error. I get similar errors on other collections which have . in their name; I do not get errors when opening other collections built (as far as I can remember) at the same time from the same data, if their name does not include a full stop. When I try renaming the collection without the full stop, I get the same error message. When I try to issue the command ALTER DATABASE MEP.bigbooks MEPbigbooks from the server command area of the GUI, I get a short syntax summary in the Query Info area complaining about the syntax of the command. When I replace MEP.bigbooks with MEP\.bigbooks and "MEP.bigbooks", I also get syntax errors. If I close the GUI and just rename the directory within my BaseXData directory, the database appears to open normally. I think I have two questions: Q1 is just renaming the directory a safe way (assuming no server is currently working with the data) to rename a collection? Should I do the same for all the other collections I have that don't currently open? I assume that if the 7.2 GUI won't let me rename them, it also will have trouble deleting them, so a related question is: is just deleting a sub-directory of BaseXData a safe way to delete a collection? Q2 Did the rules for names of collections change? Or is there some other cause? Speaking for myself, I guess that as a user I haven't thought much about what characters should be allowed in collection names, but I may have assumed that if they are not unrestricted, they would be restricted to being legal NCNames. I do kind of like using dots in names, so you can count this as one vote for relaxing the naming rules at some convenient moment. It's not a really important point, of course. best, Michael -- **************************************************************** * C. M. Sperberg-McQueen, Black Mesa Technologies LLC * http://www.blackmesatech.com * http://cmsmcq.com/mib * http://balisage.net ****************************************************************

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XqueryDebugger
by Rob Stapper 16 May '13

16 May '13

Hi, Making intensive use of mappings {} and high-order recursive functions, I really could do with a nice debugger for the Xquery in BaseX. Is a debugger in the planning? Thnx. Regards, Rob Stapper

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Namespaces on element construction
by Arto Viitanen 14 May '13

14 May '13

Why does this query (on BaseX 7.5, basexgui) let $ns := namespace {''} {'the-namespace'} let $c1 := <c xmlns="the-namespace">text</c> let $c2 := <c>{ $ns,'text'}</c> let $c3 := element {'c'} {$ns,'text'} let $qn := QName($ns, 'c') let $c4 := element {$qn} {'text'} let $nl := "
" return ($c1,$nl, $c2,$nl, $c3,$nl, $c4,$nl, '|' || namespace-uri-from-QName(node-name($c1)) || '|',$nl, '|' || namespace-uri-from-QName(node-name($c2)) || '|',$nl, '|' || namespace-uri-from-QName(node-name($c3)) || '|',$nl, '|' || namespace-uri-from-QName(node-name($c4)) || '|',$nl) outputs <c xmlns="the-namespace">text</c> <c xmlns="the-namespace">text</c> <c xmlns="the-namespace">text</c> <c xmlns="the-namespace">text</c> |the-namespace| || || |the-namespace| I.e, the namespace seems to exist on all four cases when outputted, by node-name finds it only if the namespace is given in element as text, or as QName value in computed element. -- Arto Viitanen Microteam Oy Finland

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Setting up RESTXQ in more than one place
by Wendell Piez 02 Mar '13

02 Mar '13

Hi BaseX, Did I mention recently what a great product you have here? So I have found by tweaking webapp/WEB-INF/web.xml I can point BaseX to someplace other than its restxq directory to find its RESTXQ .xqm files. This is cool. (I am encapsulating code for maximum portability and this is a help.) But in this project we are also looking forward to when we'll be serving multiple different datasets with different document types and logic, and we wish to keep them separate. Will I be able to ask BaseX to look in more than one place for its RESTXQ? (For its databases?) Thanks -- Wendell -- Wendell Piez | http://www.wendellpiez.com XML | XSLT | electronic publishing Eat Your Vegetables _____oo_________o_o___ooooo____ooooooo_^

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Whitespace anomaly running XSLT from BaseX
by Wendell Piez 01 Mar '13

01 Mar '13

Friends, I am encountering an odd whitespace-handling anomaly in BaseX when invoking Saxon to transform files behind RESTXQ. Briefly, if I have this in my XSLT: <xsl:text> </xsl:text> (the common way to get a space character in my result) I get nothing, and this <xsl:text> Boo! </xsl:text> gets me "Boo!" (leading and trailing whitespace trimmed). But I can't duplicate this behavior running BaseX from the GUI. I am sure there is a 'trim' or 'chop' setting somewhere that is allowing this, but I don't know where to look. Any ideas? Thanks, Wendell -- Wendell Piez | http://www.wendellpiez.com XML | XSLT | electronic publishing Eat Your Vegetables _____oo_________o_o___ooooo____ooooooo_^

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RestXQ parameter matching
by Wendell Piez 27 Feb '13

27 Feb '13

Hi, I have this bit of RestXQ: declare %restxq:path("test/{$id}.html") %output:method("xhtml") %output:omit-xml-declaration("no") %output:doctype-public("-//W3C//DTD XHTML 1.0 Transitional//EN") %output:doctype-system("http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd") function me:testing($id as xs:string) { let $db := db:open("myDB") return <html> <body> <h1>{$id }</h1> </body> </html> Hitting http://localhost:8984/restxq/test/testing.html, I expect to see "testing" big and bold. But I see "testing.html". Any clue as to what I'm doing wrong? Thanks, Wendell -- Wendell Piez | http://www.wendellpiez.com XML | XSLT | electronic publishing Eat Your Vegetables _____oo_________o_o___ooooo____ooooooo_^

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