Generate XML out of XPath Expressions

create-xml-from-list-of-xpath-value-pairs.xqy

import module namespace mem = "http://xqdev.com/in-mem-update"
  at "/MarkLogic/appservices/utils/in-mem-update.xqy" ;

declare variable $DEBUG as xs:boolean := fn:true() ;
(: hack because the inmem update looses the right focus
 : if you have an idea on a workaround, please let me know
 :)
declare variable $redo as xs:string* := ();

(: functional ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::)
declare function local:fst( $l )         { $l[1] } ;
declare function local:snd( $l )         { $l[2] } ;
declare function local:head( $l )        { local:fst( $l ) } ;
declare function local:tail( $l )        { fn:subsequence( $l, 2 )    } ;
declare function local:fold($f, $z, $l) { 
  if( fn:empty( $l ) ) then $z else
    local:fold( $f, 
                xdmp:apply( $f, $z, local:head( $l ) ),
                local:tail( $l ) ) } ;
declare function local:head-two( $l )   { fn:subsequence( $l, 1, 2 ) } ;
declare function local:tail-two( $l )    { fn:subsequence( $l, 3 )    } ;
declare function local:fold2($f, $z, $l) { 
  if( fn:empty( $l ) ) then $z else
    local:fold2( $f, 
                xdmp:apply( $f, $z, local:head-two( $l ) ),
                local:tail-two( $l ) ) } ;
(:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::)
declare function local:log( $string ) {
  if ($DEBUG) then xdmp:log ( $string ) else () } ;

declare function local:replace-value( $node, $value ) {
  if( xdmp:node-kind($node) = "attribute" )
  then mem:node-replace( $node, 
    attribute { fn:node-name( $node ) } { $value } )
  else mem:node-replace( $node, 
    element   { fn:node-name( $node ) } { $value } ) } ;

declare function local:insert-child( $parent, $child ) {
  if( xdmp:node-kind($child) = "attribute" )
  then mem:node-insert-before( ($parent/*)[1] , $child )
  else mem:node-insert-child( $parent , $child ) } ;

declare function local:create-nodes( $current-node, $xpath-step ) {
  let $current-node-name := $current-node /fn:local-name(.)
    let $new-node        := 
      if ( fn:starts-with( $xpath-step, "@") )
      then attribute { fn:substring( $xpath-step, 2 ) } {}
      else element   { $xpath-step } {}
    let $new-node-name   := $new-node /fn:local-name(.)
    let $steps := fn:string-join( local:tail( $redo ), "/" )
    let $child := 
      if( $steps )
      then 
let $_ := xdmp:log( " ~~steps" )
        return xdmp:unpath( fn:concat( "$current-node/", $steps ) )
      else
let $_ := xdmp:log( " ~~no-steps" )
              return xdmp:unpath( fn:concat( "$current-node/", $xpath-step ) )
let $_ := xdmp:set( $redo, ( $redo, $xpath-step ) )
let $_ := local:log( "    .................." )
let $_ := local:log( "    local:create-nodes" )
let $_ := local:log( fn:concat("     r=", $steps ) )
let $_ := local:log( fn:concat("     c=", xdmp:quote($current-node)) )
let $_ := local:log( fn:concat("     s=", $xpath-step) )
let $_ := local:log( fn:concat("    cn=", xdmp:quote( $current-node-name ) ) )
let $_ := local:log( fn:concat("     n=", xdmp:quote( $new-node ) ) )
let $_ := local:log( fn:concat("    nn=", xdmp:quote( $new-node-name ) ) )
let $_ := local:log( fn:concat("     t=", $steps ) )
let $_ := local:log( fn:concat("    ch=", xdmp:quote( $child ) ) )
    return if( fn:empty( $current-node )  ) 
      then $new-node
      else if( $current-node-name = $new-node-name )
        then $current-node
        else
          if ( $steps ) 
          then 
            if ( $child ) 
            then local:insert-child( $child , $new-node ) 
            else local:insert-child( $current-node , $new-node )
          else 
            if( $child ) 
            then $child
            else local:insert-child( $current-node , $new-node ) } ;

declare function local:generate-tree-step( $current-tree, $xpath ) {
let $_ := local:log( "    ..................." )
let $_ := local:log( "    local:generate-tree-step" )
let $_ := local:log( fn:concat( "    z=", xdmp:quote($current-tree) ) )
let $_ := local:log( fn:concat( "    p=", fn:string-join($xpath, " ") ) )
  let $_ := xdmp:set($redo, ())
  let $f := xdmp:function( xs:QName( 'local:create-nodes' ) )
    return local:fold( $f, $current-tree,
      local:tail( fn:tokenize( $xpath, "/" ) ) )  } ;

declare function local:populate-tree-step ( $current-tree, $pair ) {
  let $xpath           := local:fst( $pair )
    let $value         := local:snd( $pair )
    let $relative-path := fn:replace($xpath, "^/\w+(/.*)", "$1")
    let $selected      :=
      xdmp:unpath( fn:concat( "$current-tree", $relative-path ) )
let $_ := local:log( fn:concat( "  -x = ", $xpath ) )
let $_ := local:log( fn:concat( "  -s = ", xdmp:quote($selected) ) )
let $_ := local:log( fn:concat( "  -v = ", $value ) )
    let $updated := local:replace-value( $selected, $value )
let $_ := local:log( fn:concat( "  -u= ", xdmp:quote($updated) ) )
    return $updated } ;

declare function local:generate-tree( $xpaths ) {
let $_ := local:log( "  local:generate-tree" )
let $_ := local:log( fn:concat( "  lst=", fn:string-join( $xpaths, ", ") ) )
  let $f := xdmp:function( xs:QName( 'local:generate-tree-step' ) )
  return local:fold( $f, (), $xpaths ) } ;

declare function local:populate-tree( $tree, $xpaths, $values ) {
  let $pairs := for $xpath at $i in $xpaths return ( $xpath, $values[$i] )
  let $f := xdmp:function( xs:QName( 'local:populate-tree-step' ) )
let $_ := local:log( "  local:populate-tree" )
let $_ := local:log( fn:concat( "  t=", xdmp:quote($tree) ) )
let $_ := local:log( fn:concat( "  p=", fn:string-join( $pairs, ", ") ) )
  return document { local:fold2( $f, $tree, $pairs ) } } ; 

declare function local:process-fields( $xpaths, $values ) {
  let $_ := local:log( "# start ############################################" )
    let $tree := local:generate-tree( $xpaths ) 
    return local:populate-tree( $tree, $xpaths, $values ) } ;

local:process-fields( 
  ( "/person/name", "/person/address/zipcode", "/person/address/street", "/person/phone", "/person/@id" ),
  ( "John Doe", "10020", "barker", "555 432-4533", "555" ) )

same-no-debug.xqy

import module namespace mem = "http://xqdev.com/in-mem-update"
  at "/MarkLogic/appservices/utils/in-mem-update.xqy" ;

(: hack because the inmem update looses the right focus
 : if you have an idea on a workaround, please let me know
 :)
declare variable $redo as xs:string* := ();

(: functional ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::)
declare function local:fst( $l )         { $l[1] } ;
declare function local:snd( $l )         { $l[2] } ;
declare function local:head( $l )        { local:fst( $l ) } ;
declare function local:tail( $l )        { fn:subsequence( $l, 2 )    } ;
declare function local:fold($f, $z, $l) { 
  if( fn:empty( $l ) ) then $z else
    local:fold( $f, 
                xdmp:apply( $f, $z, local:head( $l ) ),
                local:tail( $l ) ) } ;
declare function local:head-two( $l )   { fn:subsequence( $l, 1, 2 ) } ;
declare function local:tail-two( $l )    { fn:subsequence( $l, 3 )    } ;
declare function local:fold2($f, $z, $l) { 
  if( fn:empty( $l ) ) then $z else
    local:fold2( $f, 
                xdmp:apply( $f, $z, local:head-two( $l ) ),
                local:tail-two( $l ) ) } ;
(:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::)
declare function local:replace-value( $node, $value ) {
  if( xdmp:node-kind($node) = "attribute" )
  then mem:node-replace( $node, 
    attribute { fn:node-name( $node ) } { $value } )
  else mem:node-replace( $node, 
    element   { fn:node-name( $node ) } { $value } ) } ;

declare function local:insert-child( $parent, $child ) {
  if( xdmp:node-kind($child) = "attribute" )
  then mem:node-insert-before( ($parent/*)[1] , $child )
  else mem:node-insert-child( $parent , $child ) } ;

declare function local:create-nodes( $current-node, $xpath-step ) {
  let $current-node-name := $current-node /fn:local-name(.)
    let $new-node        := 
      if ( fn:starts-with( $xpath-step, "@") )
      then attribute { fn:substring( $xpath-step, 2 ) } {}
      else element   { $xpath-step } {}
    let $new-node-name   := $new-node /fn:local-name(.)
    let $steps := fn:string-join( local:tail( $redo ), "/" )
    let $child := 
      if( $steps )
      then xdmp:unpath( fn:concat( "$current-node/", $steps ) )
      else xdmp:unpath( fn:concat( "$current-node/", $xpath-step ) )
let $_ := xdmp:set( $redo, ( $redo, $xpath-step ) )
    return if( fn:empty( $current-node )  ) 
      then $new-node
      else if( $current-node-name = $new-node-name )
        then $current-node
        else
          if ( $steps ) 
          then 
            if ( $child ) 
            then local:insert-child( $child , $new-node ) 
            else local:insert-child( $current-node , $new-node )
          else 
            if( $child ) 
            then $child
            else local:insert-child( $current-node , $new-node ) } ;

declare function local:generate-tree-step( $current-tree, $xpath ) {
  let $_ := xdmp:set($redo, ())
  let $f := xdmp:function( xs:QName( 'local:create-nodes' ) )
    return local:fold( $f, $current-tree,
      local:tail( fn:tokenize( $xpath, "/" ) ) )  } ;

declare function local:populate-tree-step ( $current-tree, $pair ) {
  let $xpath           := local:fst( $pair )
    let $value         := local:snd( $pair )
    let $relative-path := fn:replace($xpath, "^/\w+(/.*)", "$1")
    let $selected      :=
      xdmp:unpath( fn:concat( "$current-tree", $relative-path ) )
    let $updated := local:replace-value( $selected, $value )
    return $updated } ;

declare function local:generate-tree( $xpaths ) {
  let $f := xdmp:function( xs:QName( 'local:generate-tree-step' ) )
  return local:fold( $f, (), $xpaths ) } ;

declare function local:populate-tree( $tree, $xpaths, $values ) {
  let $pairs := for $xpath at $i in $xpaths return ( $xpath, $values[$i] )
  let $f := xdmp:function( xs:QName( 'local:populate-tree-step' ) )
  return document { local:fold2( $f, $tree, $pairs ) } } ; 

declare function local:process-fields( $xpaths, $values ) {
    let $tree := local:generate-tree( $xpaths ) 
    return local:populate-tree( $tree, $xpaths, $values ) } ;

local:process-fields( 
  ( "/person/name", "/person/address/zipcode", "/person/address/street", "/person/phone", "/person/@id" ),
  ( "John Doe", "10020", "barker", "555 432-4533", "555" ) )