]> granicus.if.org Git - postgresql/commitdiff
Fix namespace handling in xpath function
authorPeter Eisentraut <peter_e@gmx.net>
Wed, 7 Jan 2015 04:06:13 +0000 (23:06 -0500)
committerPeter Eisentraut <peter_e@gmx.net>
Sun, 18 Jan 2015 03:14:21 +0000 (22:14 -0500)
Previously, the xml value resulting from an xpath query would not have
namespace declarations if the namespace declarations were attached to
an ancestor element in the input xml value.  That means the output value
was not correct XML.  Fix that by running the result value through
xmlCopyNode(), which produces the correct namespace declarations.

Author: Ali Akbar <the.apaan@gmail.com>

src/backend/utils/adt/xml.c
src/test/regress/expected/xml.out
src/test/regress/expected/xml_1.out
src/test/regress/sql/xml.sql

index 17d852d85c2bc09210375c9a8e9f51285928c487..d1122dc580cc41a640bdf5a36431e3ebbfda3fbf 100644 (file)
@@ -140,9 +140,10 @@ static bool print_xml_decl(StringInfo buf, const xmlChar *version,
                           pg_enc encoding, int standalone);
 static xmlDocPtr xml_parse(text *data, XmlOptionType xmloption_arg,
                  bool preserve_whitespace, int encoding);
-static text *xml_xmlnodetoxmltype(xmlNodePtr cur);
+static text *xml_xmlnodetoxmltype(xmlNodePtr cur, PgXmlErrorContext *xmlerrcxt);
 static int xml_xpathobjtoxmlarray(xmlXPathObjectPtr xpathobj,
-                                          ArrayBuildState **astate);
+                                          ArrayBuildState **astate,
+                                          PgXmlErrorContext *xmlerrcxt);
 #endif   /* USE_LIBXML */
 
 static StringInfo query_to_xml_internal(const char *query, char *tablename,
@@ -3593,26 +3594,41 @@ SPI_sql_row_to_xmlelement(int rownum, StringInfo result, char *tablename,
  * return value otherwise)
  */
 static text *
-xml_xmlnodetoxmltype(xmlNodePtr cur)
+xml_xmlnodetoxmltype(xmlNodePtr cur, PgXmlErrorContext *xmlerrcxt)
 {
        xmltype    *result;
 
        if (cur->type == XML_ELEMENT_NODE)
        {
                xmlBufferPtr buf;
+               xmlNodePtr      cur_copy;
 
                buf = xmlBufferCreate();
+
+               /*
+                * The result of xmlNodeDump() won't contain namespace definitions
+                * from parent nodes, but xmlCopyNode() duplicates a node along with
+                * its required namespace definitions.
+                */
+               cur_copy = xmlCopyNode(cur, 1);
+
+               if (cur_copy == NULL)
+                       xml_ereport(xmlerrcxt, ERROR, ERRCODE_OUT_OF_MEMORY,
+                                               "could not copy node");
+
                PG_TRY();
                {
-                       xmlNodeDump(buf, NULL, cur, 0, 1);
+                       xmlNodeDump(buf, NULL, cur_copy, 0, 1);
                        result = xmlBuffer_to_xmltype(buf);
                }
                PG_CATCH();
                {
+                       xmlFreeNode(cur_copy);
                        xmlBufferFree(buf);
                        PG_RE_THROW();
                }
                PG_END_TRY();
+               xmlFreeNode(cur_copy);
                xmlBufferFree(buf);
        }
        else
@@ -3654,7 +3670,8 @@ xml_xmlnodetoxmltype(xmlNodePtr cur)
  */
 static int
 xml_xpathobjtoxmlarray(xmlXPathObjectPtr xpathobj,
-                                          ArrayBuildState **astate)
+                                          ArrayBuildState **astate,
+                                          PgXmlErrorContext *xmlerrcxt)
 {
        int                     result = 0;
        Datum           datum;
@@ -3676,7 +3693,8 @@ xml_xpathobjtoxmlarray(xmlXPathObjectPtr xpathobj,
 
                                        for (i = 0; i < result; i++)
                                        {
-                                               datum = PointerGetDatum(xml_xmlnodetoxmltype(xpathobj->nodesetval->nodeTab[i]));
+                                               datum = PointerGetDatum(xml_xmlnodetoxmltype(xpathobj->nodesetval->nodeTab[i],
+                                                                                                                                        xmlerrcxt));
                                                *astate = accumArrayResult(*astate, datum,
                                                                                                   false, XMLOID,
                                                                                                   CurrentMemoryContext);
@@ -3880,9 +3898,9 @@ xpath_internal(text *xpath_expr_text, xmltype *data, ArrayType *namespaces,
                 * Extract the results as requested.
                 */
                if (res_nitems != NULL)
-                       *res_nitems = xml_xpathobjtoxmlarray(xpathobj, astate);
+                       *res_nitems = xml_xpathobjtoxmlarray(xpathobj, astate, xmlerrcxt);
                else
-                       (void) xml_xpathobjtoxmlarray(xpathobj, astate);
+                       (void) xml_xpathobjtoxmlarray(xpathobj, astate, xmlerrcxt);
        }
        PG_CATCH();
        {
index 4f1e3972dcb2c8acca273ab27de5d8ba2174b781..d06e3d98c4b085ee89f6f30dfe906f9129a10841 100644 (file)
@@ -583,6 +583,21 @@ SELECT xpath('//loc:piece/@id', '<local:data xmlns:local="http://127.0.0.1"><loc
  {1,2}
 (1 row)
 
+SELECT xpath('//loc:piece', '<local:data xmlns:local="http://127.0.0.1"><local:piece id="1">number one</local:piece><local:piece id="2" /></local:data>', ARRAY[ARRAY['loc', 'http://127.0.0.1']]);
+                                                                     xpath                                                                      
+------------------------------------------------------------------------------------------------------------------------------------------------
+ {"<local:piece xmlns:local=\"http://127.0.0.1\" id=\"1\">number one</local:piece>","<local:piece xmlns:local=\"http://127.0.0.1\" id=\"2\"/>"}
+(1 row)
+
+SELECT xpath('//loc:piece', '<local:data xmlns:local="http://127.0.0.1" xmlns="http://127.0.0.2"><local:piece id="1"><internal>number one</internal><internal2/></local:piece><local:piece id="2" /></local:data>', ARRAY[ARRAY['loc', 'http://127.0.0.1']]);
+                                        xpath                                         
+--------------------------------------------------------------------------------------
+ {"<local:piece xmlns:local=\"http://127.0.0.1\" xmlns=\"http://127.0.0.2\" id=\"1\">+
+   <internal>number one</internal>                                                   +
+   <internal2/>                                                                      +
+ </local:piece>","<local:piece xmlns:local=\"http://127.0.0.1\" id=\"2\"/>"}
+(1 row)
+
 SELECT xpath('//b', '<a>one <b>two</b> three <b>etc</b></a>');
           xpath          
 -------------------------
index 044c5529ef23bff38fdf64b307c6c578578bed7d..ce67783f64320510957f39c559773db2dbf02665 100644 (file)
@@ -498,6 +498,18 @@ LINE 1: SELECT xpath('//loc:piece/@id', '<local:data xmlns:local="ht...
                                         ^
 DETAIL:  This functionality requires the server to be built with libxml support.
 HINT:  You need to rebuild PostgreSQL using --with-libxml.
+SELECT xpath('//loc:piece', '<local:data xmlns:local="http://127.0.0.1"><local:piece id="1">number one</local:piece><local:piece id="2" /></local:data>', ARRAY[ARRAY['loc', 'http://127.0.0.1']]);
+ERROR:  unsupported XML feature
+LINE 1: SELECT xpath('//loc:piece', '<local:data xmlns:local="http:/...
+                                    ^
+DETAIL:  This functionality requires the server to be built with libxml support.
+HINT:  You need to rebuild PostgreSQL using --with-libxml.
+SELECT xpath('//loc:piece', '<local:data xmlns:local="http://127.0.0.1" xmlns="http://127.0.0.2"><local:piece id="1"><internal>number one</internal><internal2/></local:piece><local:piece id="2" /></local:data>', ARRAY[ARRAY['loc', 'http://127.0.0.1']]);
+ERROR:  unsupported XML feature
+LINE 1: SELECT xpath('//loc:piece', '<local:data xmlns:local="http:/...
+                                    ^
+DETAIL:  This functionality requires the server to be built with libxml support.
+HINT:  You need to rebuild PostgreSQL using --with-libxml.
 SELECT xpath('//b', '<a>one <b>two</b> three <b>etc</b></a>');
 ERROR:  unsupported XML feature
 LINE 1: SELECT xpath('//b', '<a>one <b>two</b> three <b>etc</b></a>'...
index 90d4d67f04e289f9bee569c7c8eb349881d840a1..ce87d426842f6a1e91a014b43c9c671cc02e5843 100644 (file)
@@ -174,6 +174,8 @@ SELECT xpath(NULL, NULL) IS NULL FROM xmltest;
 SELECT xpath('', '<!-- error -->');
 SELECT xpath('//text()', '<local:data xmlns:local="http://127.0.0.1"><local:piece id="1">number one</local:piece><local:piece id="2" /></local:data>');
 SELECT xpath('//loc:piece/@id', '<local:data xmlns:local="http://127.0.0.1"><local:piece id="1">number one</local:piece><local:piece id="2" /></local:data>', ARRAY[ARRAY['loc', 'http://127.0.0.1']]);
+SELECT xpath('//loc:piece', '<local:data xmlns:local="http://127.0.0.1"><local:piece id="1">number one</local:piece><local:piece id="2" /></local:data>', ARRAY[ARRAY['loc', 'http://127.0.0.1']]);
+SELECT xpath('//loc:piece', '<local:data xmlns:local="http://127.0.0.1" xmlns="http://127.0.0.2"><local:piece id="1"><internal>number one</internal><internal2/></local:piece><local:piece id="2" /></local:data>', ARRAY[ARRAY['loc', 'http://127.0.0.1']]);
 SELECT xpath('//b', '<a>one <b>two</b> three <b>etc</b></a>');
 SELECT xpath('//text()', '<root>&lt;</root>');
 SELECT xpath('//@value', '<root value="&lt;"/>');