Validazione e decodifica di file XML con Python

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1 Validazione e decodifica di file XML con Python PyCon Otto Aprile 2017 Davide Brunato SISSA davide.brunato@sissa.it

2 Agenda Il contesto Schemi XML Disponibilità Necessità Soluzioni Conclusioni

3 Cos è la SISSA? Centro scientifico di eccellenza italiano ed internazionale Si trova a Trieste Fondata nel 1978 Ricerca e didattica in 3 aree: Fisica Matematica Neuroscienze Circa 260 studenti di PhD Attivati 12 corsi di PhD 2 Masters in: Comunicazione della Scienza High Performance Computing

4 Materials design at the exascale Centro di eccellenza finanziato con fondi dell Unione Europea (H2020-EINFRA , project ID: ) Riguarda alcuni software di simulazione quantistica

5 Quantum ESPRESSO ESPRESSO sta per open Source Package for Research in Electronic Structure, Simulation, and Optimization Suite integrata di programmi di simulazione a livello atomico basato su DFT, pseudo-potenziali e onde piane Strutturato su alcuni programmi di simulazione progettati per interoperare anche con altri software Free open source software (licenza GPL2) Iniziativa coordinata dalla Quantum ESPRESSO Foundation, con la partecipazione di SISSA, EPFL, ICTP, CINECA, CNR, University of North Texas e con molti partner in Europa e in tutto il mondo

6 I numeri di Quantum ESPRESSO linee di codice Fortran/C 53 sviluppatori registrati utenti registrati download per ogni nuova release 3 siti web 1 mailing list con messaggi/anno 30 scuole e workshop dal 2002 con partecipanti

7 Extensible Markup Language Un meta-linguaggio Forma semplificata di SGML SGML ideato per codifiche complete di lungo periodo Pensato anche per sostituire HTML non è stato così: HTML 5 Sintassi e semantica associata Ricco di linguaggi di manipolazione: XPath: selezionare nodi di un documento XML XSLT: Trasformazione di documenti XML XQuery: ricerca in documenti XML

8 XML vs JSON?

9 Schemi XML Descrizione della struttura di documenti XML: Elementi e attributi che possono essere inclusi Ordine e ripetizione degli elementi Tipi per elementi e attributi Predicati sul contenuto Vincoli su tipi, attributi, elementi Principali linguaggi per definire schemi XML: Grammar-based (struttura, forma e sintassi) Document Type Definition (DTD) XML Schema Relax NG (relaxing) Rule-based (relazioni tra i dati) Schematron

10 Document Type Definition Linguaggio di definizione eredidato da SGML PRO: Relativamente semplice e compatto Ampiamente supportato CONTRO: Supporto ai tipi di dati e vincoli molto limitato Non supporta nativamente i namespace Non ha una sintassi XML <?xml version="1.0" encoding="utf-8"?> <!DOCTYPE vehicles [ <!ELEMENT vehicles (cars bikes)*> <!ELEMENT cars (car)*> <!ELEMENT car (#PCDATA)> <!ATTLIST car make CDATA #REQUIRED model CDATA #REQUIRED> <!ELEMENT bikes (bike)*> <!ELEMENT bike (#PCDATA)> <!ATTLIST bike make CDATA #REQUIRED model CDATA #REQUIRED> ]> <vehicles> <cars> <car make="porsche" model="911" /> <car make="porsche" model="911" /> </cars> <bikes> <bike make="harley-davidson" model="wl" /> <bike make="yamaha" model="xs650" /> </bikes> </vehicles>

11 XML Schema Sviluppato da W3C v.1.0 del 2001, v. 1.1 del 2012 Preceduto da XDR, DCD, SOX, DDML PRO: Include dati predefiniti Supporto per definire nuovi tipi di dati Vincoli sui tipi e sul modello Asserzioni (dalla v 1.1) Definizioni locali e globali CONTRO: Abbastanza complesso Schemi più lunghi <xs:schema attributeformdefault="unqualified" elementformdefault="qualified" xmlns:xs=" <xs:element name="vehicles"> <xs:complextype> <xs:sequence> <xs:element name="cars"> <xs:complextype> <xs:sequence> <xs:element name="car" maxoccurs="unbounded" minoccurs="0"> <xs:complextype> <xs:simplecontent> <xs:extension base="xs:string"> <xs:attribute type="xs:string" name="make" use="optional"/> <xs:attribute type="xs:string" name="model" use="optional"/> </xs:extension> </xs:simplecontent> </xs:complextype> </xs:element> </xs:sequence> </xs:complextype> </xs:element> <xs:element name="bikes"> <xs:complextype> <xs:sequence> <xs:element name="bike" maxoccurs="unbounded" minoccurs="0"> <xs:complextype> <xs:simplecontent> <xs:extension base="xs:string"> <xs:attribute type="xs:string" name="make" use="optional"/> <xs:attribute type="xs:string" name="model" use="optional"/> </xs:extension> </xs:simplecontent> </xs:complextype> </xs:element> </xs:sequence> </xs:complextype> </xs:element> </xs:sequence> </xs:complextype> </xs:element> </xs:schema>

12 Relax NG Sviluppato da un comitato tecnico OASIS PRO: Più semplice rispetto a XML Schema Lo schema del documento Migliore supporto per modelli non ordinati Disponibile anche in formato compatto non-xml CONTRO: Non ha tipi di dato predefiniti Poco supporto per definire tipi <grammar ns="" xmlns=" datatypelibrary=" <start> <element name="vehicles"> <element name="cars"> <oneormore> <element name="car"> <attribute name="make"> <data type="ncname"/> </attribute> <attribute name="model"> <data type="integer"/> </attribute> </element> </oneormore> </element> <element name="bikes"> <oneormore> <element name="bike"> <attribute name="make"> <data type="ncname"/> </attribute> <attribute name="model"> <data type="ncname"/> </attribute> </element> </oneormore> </element> </element> </start> </grammar>

13 Relax NG: forma compatta default namespace = "" start = element vehicles { element cars { element car { attribute make { xsd:ncname }, attribute model { xsd:integer } }+ }, element bikes { element bike { attribute make { xsd:ncname }, attribute model { xsd:ncname } }+ } } <grammar ns="" xmlns=" datatypelibrary=" <start> <element name="vehicles"> <element name="cars"> <oneormore> <element name="car"> <attribute name="make"> <data type="ncname"/> </attribute> <attribute name="model"> <data type="integer"/> </attribute> </element> </oneormore> </element> <element name="bikes"> <oneormore> <element name="bike"> <attribute name="make"> <data type="ncname"/> </attribute> <attribute name="model"> <data type="ncname"/> </attribute> </element> </oneormore> </element> </element> </start> </grammar>

14 Schematron Basato su regole XPath ISO Schematron (2006, 2016) XML valido se non viola regole PRO Facile da imparare e usare Espressività e flessibilità CONTRO Non ha modello di dati Niente tipi né defaults Impatto errori nello schema <schema xmlns=" <title>vehicles</title> <pattern id="vehicles-rules"> <rule context="vehicles"> <assert test="cars">no list of cars!</assert> <assert test="bikes">no list of bikes!</assert> </rule> <rule context="vehicles:cars"> <report test="car">you have a car!</report> </rule> <rule context="vehicles:bikes"> <report test="bike">you have a bike!</report> </rule> </pattern> </schema>

15 XML Schema: elementi all alternative annotation any anyattribute appinfo assert assertion attribute attributegroup choice complexcontent complextype element enumeration extension field fractiondigits group import include key length list maxexclusive maxinclusive maxlength minexclusive mininclusive minlength notation pattern redefine schema selector sequence simplecontent simpletype totaldigits union unique whitespace <xs:schema xmlns:xs=" xmlns:vh=" targetnamespace=" elementformdefault="qualified"> <xs:include schemalocation="cars.xsd"/> <xs:include schemalocation="bikes.xsd"/> <xs:element name="vehicles"> <xs:complextype> <xs:sequence> <xs:element ref="vh:cars" /> <xs:element ref="vh:bikes" /> </xs:sequence> </xs:complextype> </xs:element> <xs:attribute type="xs:positiveinteger" name="step"/> </xs:schema>

16 XML Schema: strutture Tipi Semplici Attributi Gruppi di Attributi Elementi Gruppi (modello) Tipi Complessi

17 XML Schema: tipi semplici Si applicano ad attributi ed elementi Derivazione come: Restrizione Lista Unione <simpletype name="lowhightype"> <restriction base="string"> <enumeration value="low"/> <enumeration value="high"/> </restriction> </simpletype> <simpletype name="constr_parms_listtype"> <restriction> <simpletype> <list itemtype="double"/> </simpletype> <length value="4"/> </restriction> </simpletype> <simpletype final = (#all (list union restriction)) id = ID name = NCName {any attributes with non-schema namespace...}> Content: (annotation?, (restriction list union)) </simpletype>

18 XML Schema: restrizioni Definizione vincoli (facets) Ammessa anche vuota 12 facets (14 XSD 1.1) <xs:simpletype name="farenheitwatertemp"> <xs:restriction base="xs:decimal"> <xs:fractiondigits value="2"/> <xs:minexclusive value="0.00"/> <xs:maxexclusive value="100.00"/> </xs:restriction> </xs:simpletype> <restriction base = QName id = ID {any attributes with non-schema namespace...}> Content: (annotation?, (simpletype?, (minexclusive mininclusive maxexclusive maxinclusive totaldigits fractiondigits length minlength maxlength enumeration whitespace pattern)*)) </restriction>

19 XML Schema: tipi built-in

20 XML Schema: attributi Nome o riferimento Valore di default Valore fisso <xs:attribute name="space"> <xs:simpletype> <xs:restriction base="xs:ncname"> <xs:enumeration value="default"/> <xs:enumeration value="preserve"/> </xs:restriction> </xs:simpletype> </xs:attribute> Uso <xs:attribute name="base" type="xs:anyuri"/> Attributi ammessi in un tipo complesso <xs:attribute name="id" type="xs:id"/> <attribute default = string fixed = string form = (qualified unqualified) id = ID name = NCName ref = QName type = QName use = (optional prohibited required) : optional {any attributes with non-schema namespace...}> Content: (annotation?, (simpletype?)) </attribute>

21 XML Schema: gruppi di attributi Attributi ammessi in un tipo complesso Solo definizioni globali Non partecipano alla validazione <xs:attributegroup name="i18n"> <xs:attribute name="lang" type="languagecode"/> <xs:attribute ref="xml:lang"/> <xs:attribute name="dir"> <xs:simpletype> <xs:restriction base="xs:token"> <xs:enumeration value="ltr"/> <xs:enumeration value="rtl"/> </xs:restriction> </xs:simpletype> </xs:attribute> </xs:attributegroup> <xs:attributegroup name="attrs"> <xs:attributegroup ref="coreattrs"/> <xs:attributegroup ref="i18n"/> <xs:attributegroup ref="events"/> </xs:attributegroup> <attributegroup id = ID name = NCName ref = QName {any attributes with non-schema namespace...}> Content: (annotation?, ((attribute attributegroup)*, anyattribute?)) </attributegroup>

22 XML Schema: elementi Elementi ammessi Tipo semplice o complesso Nome o riferimento Valore di default Valore fisso Occorrenza <xs:element name="purchaseorder" type="purchaseordertype"/> <xs:element name="gift"> <xs:complextype> <xs:sequence> <xs:element name="birthday" type="xs:date"/> <xs:element ref="purchaseorder"/> </xs:sequence> </xs:complextype> </xs:element> <element abstract = boolean : false block = (#all List of (extension restriction substitution)) default = string final = (#all List of (extension restriction)) fixed = string form = (qualified unqualified) id = ID maxoccurs = (nonnegativeinteger unbounded) : 1 minoccurs = nonnegativeinteger : 1 name = NCName nillable = boolean : false ref = QName substitutiongroup = QName type = QName {any attributes with non-schema namespace...}> Content: (annotation?, ((simpletype complextype)?, (unique key keyref)*)) </element>

23 XML Schema: gruppi Definizioni solo globali Definiscono il modello Scelte Sequenze ordinate Sequenze non ordinate Annidamento di gruppi Occorrenza <xs:group name="special.pre"> <xs:choice> <xs:element ref="br"/> <xs:element ref="span"/> <xs:element ref="bdo"/> <xs:element ref="map"/> </xs:choice> </xs:group> <xs:group name="special"> <xs:choice> <xs:group ref="special.pre"/> <xs:element ref="object"/> <xs:element ref="img"/> </xs:choice> </xs:group> <group id = ID maxoccurs = (nonnegativeinteger unbounded) : 1 minoccurs = nonnegativeinteger : 1 name = NCName ref = QName {any attributes with non-schema namespace...}> Content: (annotation?, (all choice sequence)?) </group>

24 XML Schema: tipi complessi Definiscono tipi con attributi Tipo di contenuto Semplice Complesso Derivazione: Restrizione Estensione <xs:complextype name="purchaseordertype"> <xs:sequence> <xs:element name="shipto" type="usaddress"/> <xs:element name="billto" type="usaddress"/> <xs:element ref="comment" minoccurs="0"/> <xs:element name="items" type="items"/> </xs:sequence> <xs:attribute name="orderdate" type="xs:date"/> </xs:complextype> <complextype abstract = boolean : false block = (#all List of (extension restriction)) final = (#all List of (extension restriction)) id = ID mixed = boolean : false name = NCName {any attributes with non-schema namespace...}> Content: (annotation?, (simplecontent complexcontent ((group all choice sequence)?, ((attribute attributegroup)*, anyattribute?)))) </complextype>

25 XML Schema: schema <xs:schema xmlns:xs=" xmlns:xlink=" targetnamespace=" <xs:include schemalocation="cars.xsd"/> <xs:include schemalocation="bikes.xsd"/> <xs:import namespace=" schemalocation="xml.xsd"/> <xs:import namespace=" schemalocation="xlink.xsd"/> <!-- seguono le dichiarazioni globali </xs:schema>

26 XML Schema: considerazioni Adatto per dati strutturati Molto espressivo Problemi di interoperabilità delle implementazioni XSD 1.1 da implementare Complicato!? Eventualmente il Primer W3C: Poi un libro buono (ce ne sono pochi) Alcuni errori sono anche difficili da interpretare: When <simplecontent> is used, the base type must be a complextype whose content type is simple, or, only if restriction is specified, a complex type with mixed content and emptiable particle, or, only if extension is specified, a simple type.

27 Validazione di documenti XML Verifica che un documento XML soddisfi entrambe le condizioni: sia ben formato (well-formed) sia valido rispetto ad un determinato schema XML schema (.xsd) XML Schema validator well-formed XML instance (.xml) XML instance is valid/invalid

28 PSVI Post Schema Validation Infoset Concetto introdotto con XML Schema Esprime un documento XML come modello di dati Documento XML come oggetto PSVI contiene Vocabolario (nomi di elementi e attributi) Il modello di contenuto I tipi di dati

29 Validatori XML Schema libxml2 Parte indipendente del framework di GNOME Scritta in C Implementazione XSD 1.0 quasi completa xmllint (tool di libxml2) lxml (Python bindings di libxml2) Xerces Supportato dalla Apache Foundation Disponibile per Java, C++, Perl Implementa completamente XSD 1.0 Usato in molti software (PyCharm)

30 lxml lxml is the most feature-rich and easy-to-use library for processing XML and HTML in the Python language. Libreria Python per parsing di documenti XML e HTML Rispetto alla libreria standard: Interfaccia Element Tree estesa Più veloce Supporto XPath completo Validazione (DTD, XML Schema, Relax NG) PSVI? Non disponibile dopo la validazione Non nelle C-API (file etreepublic.pxd)

31 Validare con lxml >>> import lxml.etree as etree >>> import io >>> f = io.stringio("""<xs:schema xmlns:xs=" <xs:element name="a" type="tipoa"/> <xs:complextype name="tipoa"> <xs:sequence> <xs:element name="b" type="xs:string"/> </xs:sequence> </xs:complextype> </xs:schema> """) >>> xs_document = etree.parse(f) >>> xs = etree.xmlschema(xs_document) >>> xml_document = etree.fromstring("<a><b></b></a>") >>> xs.validate(xml_document) True >>> xml_document = etree.fromstring("<a><c></c><d/></a>") >>> xs.validate(xml_document) False >>> xs.assertvalid(xml_document) Traceback (most recent call last): File "<stdin>", line 1, in <module> File "src/lxml/lxml.etree.pyx", line 3491, in lxml.etree._validator.assertvalid (src/lxml/lxml.etree.c:186663) lxml.etree.documentinvalid: Element 'C': This element is not expected. Expected is ( B )., line 1 >>> xs.error_log <string>:1:0:error:schemasv:schemav_element_content: Element 'C': This element is not expected. Expected is ( B ). >>>

32 XML in QE Output già in XML, scritto da libreria proprietaria Standardizzare l uso di XML: 1.Fortran XML library (FoX) 2.Uso di schemi XSD per descrivere l input e l output Scelto XML Schema: Tipi di dato predefiniti Orientato alle strutture dati Già usato da altri sw del gruppo &CONTROL calculation='relax' dipfield=.false. disk_io='low' dt=20.0 etot_conv_thr= forc_conv_thr=0.001 input_xml_schema_file='al001_relax_bfgs.xml' iprint= max_seconds= outdir='/tmp/espresso/tempdir' prefix='al' pseudo_dir='/tmp/espresso/pseudo' restart_mode='from_scratch' title='' tprnfor=.false. tstress=.false. verbosity='high' wf_collect=.false. / &SYSTEM degauss=0.05 ecutwfc=12.0 force_symmorphic=.false. ibrav=0 input_dft='pz' lspinorb=.false. nat=7 no_t_rev=.false. noinv=.false. noncolin=.false. nosym=.false. nosym_evc=.false. nspin=1 /

33 XML Schema in QE Uno schema per applicativo: PW (2016) Phonon (2016) Neb (2017) Uso dello schema: Convertire l input XML nel formato namelist Fortran Strutturare l output XML Costruire codice Fortran per i dati di output Validare i dati prodotti

34 Convertitore input di PW Problema iniziale: PW XML Input XML to Namelist translator PW input file (namelists and cards) Non c è corrispondenza biunivoca tra Input XML e Namelist Alcuni parametri namelist sono funzione di più parametri XML Python per il post-processing di QE Decomposizione del problema: qes.xsd XML XML Schema Decoder Python dictionary Namelist translator Fortran namelist

35 Decoder XML Schema Semplice costruire un dizionario Non banale convertire i tipi base Più complicato con tipi derivati <complextype name="total_energytype"> <sequence> <element type="double" name="etot"/> <element type="double" name="eband" minoccurs="0"/> <element type="double" name="ehart" minoccurs="0"/> <element type="double" name="vtxc" minoccurs="0"/> <element type="double" name="etxc" minoccurs="0"/> <element type="double" name="ewald" minoccurs="0"/> <element type="double" name="demet" minoccurs="0"/> <element type="double" name="efieldcorr" minoccurs="0"/> <element type="double" name="potentiostat_contr" minoccurs="0"/> </sequence> </complextype> <simpletype name="doublelisttype"> <list itemtype="double"/> </simpletype> <complextype name="matrixtype"> <simplecontent> <extension base="qes:doublelisttype" /> </simplecontent> </complextype>

36 Oltre il decoder XSD Altri schemi per QE da definire Modifiche agli schemi esistenti Complessità parsing XSD Codice testato anche con altri schemi Validatore lxml non utile per decodifica Convertitore XML + PyCon 7 (jsonschema) xmlschema

37 xmlschema >>> import xmlschema >>> import io >>> f = io.stringio(""" <xs:schema xmlns:xs=" <xs:element name="a" type="tipoa"/> <xs:complextype name="tipoa"> <xs:sequence> <xs:element name="b" type="xs:string"/> </xs:sequence> </xs:complextype> </xs:schema>""") >>> xs = xmlschema.xmlschema(f) >>> xs.is_valid("<a><b></b></a>") True >>> xs.is_valid("<a><c></c></a>") False

38 xmlschema: errore di validazione >>> xs.validate("<a><b></b></a>") >>> xs.validate("<a><c></c></a>") Traceback (most recent call last): File "<stdin>", line 1, in <module> File "/usr/lib/python3.5/site-packages/xmlschema/schema.py", line 385, in validate raise error xmlschema.exceptions.xmlschemavalidationerror: failed validating 'C' with <XsdGroup 'None' at 0x7fc7f5d45d68>. Reason: element not in schema! Schema: <xs:sequence xmlns:xs=" <xs:element name="b" type="xs:string" /> </xs:sequence> Instance: <C />

39 xmlschema: generazione errori >>> [e for e in xs.iter_errors("<a><b></b></a>")] [] >>> [e for e in xs.iter_errors("<a><c></c></a>")] [XMLSchemaValidationError(<XsdGroup 'None' at 0x7fc7f5d45d68>, 'C', 'element not in schema!', <Element 'C' at 0x7fc7f430ab88>, <Element '{ at 0x7fc7f430a408>), XMLSchemaValidationError(<XsdElement 'B' at 0x7fc7f5d45da0>, <Element 'A' at 0x7fc7f430aae8>, "tag 'B' expected.")] >>>

40 xmschema: XSD errato >>> f = io.stringio(""" <xs:schema xmlns:xs=" <xs:element name="a" type="tipoax"/> <xs:complextype name="tipoa"> <xs:sequence> <xs:element name="b" type="xs:string"/> </xs:sequence> </xs:complextype> </xs:schema>""") >>> xs = xmlschema.xmlschema(f) Traceback (most recent call last): File "<stdin>", line 1, in <module> File "/usr/lib/python3.5/site-packages/xmlschema/schema.py", line 266, in init self.maps.build() File "/usr/lib/python3.5/site-packages/xmlschema/schema.py", line 152, in build build_xsd_elements(self.elements, XSD_ELEMENT_TAG, **kwargs) File "/usr/lib/python3.5/site-packages/xmlschema/xsdbase.py", line 403, in build_xsd_map raise errors[0] if errors else XMLSchemaParseError(message=str(err), elem=elem) File "/usr/lib/python3.5/site-packages/xmlschema/xsdbase.py", line 381, in build_xsd_map elem, schema, is_global=true, **kwargs File "/usr/lib/python3.5/site-packages/xmlschema/factories.py", line 60, in xsd_factory_wrapper result = factory_function(elem, schema, instance, **kwargs) File "/usr/lib/python3.5/site-packages/xmlschema/factories.py", line 733, in xsd_element_factory element_type = xsd_lookup(type_qname, schema.maps.types) File "/usr/lib/python3.5/site-packages/xmlschema/xsdbase.py", line 305, in xsd_lookup raise XMLSchemaLookupError("Missing XSD reference %r!" % qname) xmlschema.exceptions.xmlschemalookuperror: Missing XSD reference 'TipoAx'!

41 xmlschema: validazione XSD >>> f = io.stringio(""" <xs:schema xmlns:xs=" <xs:element name="a" type="tipoa"/> <xs:complextype name="tipoa"> <xs:sequence> <xs:element name="b" type="xs:string"/> </xs:sequence> </xs:complextype> <xs:simplextype name="lista_interi"> <xs:list itemtype="xs:int"/> </xs:simplextype> </xs:schema>""") >>> xs = xmlschema.xmlschema(f, check_schema=true) Traceback (most recent call last): File "<stdin>", line 1, in <module> File "/usr/lib/python3.5/site-packages/xmlschema/schema.py", line 261, in init self.check_schema(self.root) File "/usr/lib/python3.5/site-packages/xmlschema/schema.py", line 310, in check_schema raise error xmlschema.exceptions.xmlschemavalidationerror: failed validating '{ with <XsdGroup 'None' at 0x7f562900bc88>. Reason: element not in schema! Schema: <xs:complexcontent xmlns:xs=" <xs:extension base="xs:openattrs"> </xs:complexcontent> Instance: <xs:simplextype xmlns:xs=" name="lista_interi"> <xs:list itemtype="xs:int" /> </xs:simplextype>

42 xmlschema: PSVI >>> xs.types {'TipoA': <XsdComplexType 'TipoA' at 0x7fc7f5d45320>} >>> xs.elements {'A': <XsdElement 'A' at 0x7fc7f62e19b0>} >>> xs.namespaces {'': '', 'xs': ' 'xml': ' >>> xs.target_namespace '' >>>

43 xmlschema: la decodifica >>> import xmlschema >>> import io >>> f = io.stringio(""" <xs:schema xmlns:xs=" <xs:element name="a" type="tipoa"/> <xs:complextype name="tipoa"> <xs:sequence> <xs:element name="b" type="xs:string"/> <xs:element name="c" type="xs:int"/> <xs:element name="d" type="xs:float"/> </xs:sequence> </xs:complextype> </xs:schema>""") >>> xs = xmlschema.xmlschema(f) >>> xs.to_dict("<a><b>nome</b><c>99</c><d> </d></a>") {'D': , 'B': 'Nome', 'C': 99} >>> d = xs.to_dict("<a><b>nome</b><c>99.9</c><d> </d></a>") Traceback (most recent call last): File "<stdin>", line 1, in <module> File "/home/brunato/development/projects/xmlschema/xmlschema/schema.py", line 410, in to_dict return self.maps.elements[xml_root.tag].decode(xml_root) File "/home/brunato/development/projects/xmlschema/xmlschema/xsdbase.py", line 531, in decode raise obj xmlschema.exceptions.xmlschemadecodeerror: cannot decode '99.9' using the type <class 'int'> of validator <XsdAtomicBuiltin '{ at 0x7fd >.

44 xmlschema: builtins Alcuni schemi sono di base: XML XSD (1.0/1.1) XSI (XML Schema Instance) XLink HFP (Has Facet and Property) Tipi built-in definiti direttamente: Decodifica/codifica tipi semplici Maggior velocità Agganciati al meta-schema XSD

45 xmlschema: stato Prima versione stabile: febbraio 2017 Testato con 200+ schemi Implementa ~80% XSD 1.0 Utilizzato da QE Da adottare in altri software MaX (plugins Aiida)

46 xmlschema: note Decodifica e validazione strettamente connesse OOP per rappresentare strutture XSD Fabric functions interconnesse (kwargs!) Decoratori Closures Type Checking (con moderazione ) La libreria di Python aiuta TODO: XSD 1.0 e 1.1 al 100% XPath Encoding completo

47 Conclusioni?

48 XML Schema in Python??? Si può fareee!!!