xslt: accept text or paths, generate Preserves data

assertions.prs

@@ -9,6 +9,6 @@ Pulse = <pulse @periodSec float @proxy #:any>.
 
 XmlTranslation = <xml-translation @xml string @pr any>.
 
-XsltTransform = <xslt-transform @stylesheet string @input string @output string>.
+XsltTransform = <xslt-transform @stylesheet string @input string @output any>.
 XsltItems = [XsltItem ...].
 XsltItem = string.

src/schema/assertions.nim

@@ -20,7 +20,7 @@ type
   XsltTransform* {.preservesRecord: "xslt-transform".} = object
     `stylesheet`*: string
     `input`*: string
-    `output`*: string
+    `output`*: Value
 
 proc `$`*(x: XsltItems | Pulse | XsltItem | XmlTranslation | FileSystemUsage |
     XsltTransform): string =

src/syndesizer/xslt_actor.nim

@@ -1,6 +1,7 @@
 # SPDX-FileCopyrightText: ☭ Emery Hemingway
 # SPDX-License-Identifier: Unlicense
 
+import std/[os, strutils]
 import preserves, syndicate
 import ../schema/[assertions, config]
 
@@ -10,14 +11,90 @@ import ../schema/[assertions, config]
 {.pragma: libxslt, header: "libxslt/xslt.h", importc.}
 
 type
+  xmlElementType {.libxslt.} = enum
+    XML_ELEMENT_NODE = 1,
+    XML_ATTRIBUTE_NODE = 2,
+    XML_TEXT_NODE = 3,
+    XML_CDATA_SECTION_NODE = 4,
+    XML_ENTITY_REF_NODE = 5,
+    XML_ENTITY_NODE = 6,
+    XML_PI_NODE = 7,
+    XML_COMMENT_NODE = 8,
+    XML_DOCUMENT_NODE = 9,
+    XML_DOCUMENT_TYPE_NODE = 10,
+    XML_DOCUMENT_FRAG_NODE = 11,
+    XML_NOTATION_NODE = 12,
+    XML_HTML_DOCUMENT_NODE = 13,
+    XML_DTD_NODE = 14,
+    XML_ELEMENT_DECL = 15,
+    XML_ATTRIBUTE_DECL = 16,
+    XML_ENTITY_DECL = 17,
+    XML_NAMESPACE_DECL = 18,
+    XML_XINCLUDE_START = 19,
+    XML_XINCLUDE_END = 20
+
+  xmlNsPtr = ptr xmlNs
+  xmlNs {.libxslt.} = object
+    next: xmlNsPtr
+    href, prefix: cstring
+
+  xmlAttrPtr = ptr xmlAttr
+  xmlAttr {.libxslt.} = object
+    name: cstring
+    next: xmlAttrPtr
+    children: xmlNodePtr
+
+  xmlElementContentPtr = ptr xmlElementContent
+  xmlElementContent {.libxslt.} = object
+    encoding: cstring
+
+  xmlNodePtr = ptr xmlNode
+  xmlNode {.libxslt.} = object
+    `type`: xmlElementType
+    name: cstring
+    children, next: xmlNodePtr
+    content: cstring
+    properties: xmlAttrPtr
+    nsDef: xmlNsPtr
+
   xmlDocPtr {.libxslt.} = distinct pointer
   xsltStylesheetPtr {.libxslt.} = distinct pointer
 
+proc isNil(x: xmlDocPtr): bool {.borrow.}
+proc isNil(x: xsltStylesheetPtr): bool {.borrow.}
+
+proc xmlReadMemory(buf: pointer; len: cint; url, enc: cstring; opts: cint): xmlDocPtr {.libxslt.}
+
+proc xmlReadMemory(buf: string; uri = "noname.xml"): xmlDocPtr =
+  xmlReadMemory(buf[0].addr, buf.len.cint, uri, "UTF-8", 0)
+
 proc xmlParseFile(filename: cstring): xmlDocPtr {.libxslt.}
+
 proc xmlFreeDoc(p: xmlDocPtr) {.libxslt.}
 
+proc xmlDocGetRootElement(doc: xmlDocPtr): xmlNodePtr {.libxslt.}
+
+proc loadXmlDoc(text: string): xmlDocPtr =
+  if text.startsWith("/") and fileExists(text):
+    xmlParseFile(text)
+  else:
+    xmlReadMemory(text, "noname.xml")
+
 proc xsltParseStylesheetFile(filename: cstring): xsltStylesheetPtr {.libxslt.}
 
+proc xsltParseStylesheetDoc(doc: xmlDocPtr): xsltStylesheetPtr {.libxslt.}
+
+proc xsltParseStylesheetDoc(text: string; uri = "noname.xml"): xsltStylesheetPtr =
+  var doc = xmlReadMemory(text, uri)
+  result = xsltParseStylesheetDoc(doc)
+    # implicit free of doc
+
+proc loadStylesheet(text: string): xsltStylesheetPtr =
+  if text.startsWith("/") and fileExists(text):
+    xsltParseStylesheetFile(text)
+  else:
+    xsltParseStylesheetDoc(text, "noname.xsl")
+
 proc xsltApplyStylesheet(
     style: xsltStylesheetPtr, doc: xmlDocPtr,  params: cstringArray): xmlDocPtr {.libxslt.}
 
@@ -41,27 +118,91 @@ proc xsltSaveResultToString(res: xmlDocPtr; style: xsltStylesheetPtr): string =
 proc initLibXml =
   discard
 
+proc XML_GET_CONTENT(xn: xmlNodePtr): xmlElementContentPtr {.libxslt.}
+
+proc textContent(xn: xmlNodePtr): string =
+  if xn.content != nil: result = $xn.content
+
+proc content(attr: xmlAttrPtr): string =
+  var child = attr.children
+  while not child.isNil:
+    result.add child.content
+    child = child.next
+
+proc preserveSiblings(result: var seq[Value]; first: xmlNodePtr) =
+  var xn = first
+  while not xn.isNil:
+    case xn.type
+    of XML_ELEMENT_NODE:
+      var child = Value(kind: pkRecord)
+      if not xn.nsDef.isNil:
+        child.record.add initDictionary()
+        var ns = xn.nsDef
+        while not ns.isNil:
+          if not ns.href.isNil:
+            var key = Value(kind: pkString)
+            if ns.prefix.isNil:
+              key.string = "xmlns"
+            else:
+              key.string = "xmlns:" & $ns.prefix
+            child.record[0][key] = toPreserves($ns.href)
+          ns = ns.next
+
+      if not xn.properties.isNil:
+        if child.record.len < 1:
+          child.record.add initDictionary()
+        var attr = xn.properties
+        while not attr.isNil:
+          var
+            key = toPreserves($attr.name)
+            val = toPreserves(attr.content)
+          child.record[0][key] = val
+          attr = attr.next
+      if not xn.children.isNil:
+        preserveSiblings(child.record, xn.children)
+      child.record.add tosymbol($xn.name)
+      result.add child
+    of XML_TEXT_NODE:
+      result.add textContent(xn).toPreserves
+    else:
+      stderr.writeLine "not an XML_ELEMENT_NODE - ", $xn.type
+    xn = xn.next
+
+proc toPreservesHook*(xn: xmlNodePtr): Value =
+  var items = newSeqofCap[Value](1)
+  preserveSiblings(items, xn)
+  items[0]
+
 proc spawnXsltActor*(turn: var Turn; root: Cap): Actor {.discardable.} =
   spawn("xslt", turn) do (turn: var Turn):
     initLibXml()
     during(turn, root, ?:XsltArguments) do (ds: Cap):
       let sheetsPat = ?Observe(pattern: !XsltTransform) ?? {0: grab(), 1: grab()}
       during(turn, ds, sheetsPat) do (stylesheet: Literal[string], input: Literal[string]):
-        let
-          cur = xsltParseStylesheetFile(stylesheet.value)
-          doc = xmlParseFile(input.value)
-          params = allocCStringArray([])
-          res = xsltApplyStylesheet(cur, doc, params)
-          output = xsltSaveResultToString(res, cur)
-        xmlFreeDoc(res)
-        xmlFreeDoc(doc)
-        deallocCStringArray(params)
-        xsltFreeStylesheet(cur)
-        publish(turn, ds, XsltTransform(
-            stylesheet: stylesheet.value,
-            input: input.value,
-            output: output,
-          ))
+        let cur = loadStylesheet(stylesheet.value)
+        if cur.isNil:
+          stderr.writeLine "failed to parse stylesheet"
+        else:
+          let doc = loadXmlDoc(input.value)
+          if doc.isNil:
+            stderr.writeLine "failed to parse input document"
+          else:
+            let
+              params = allocCStringArray([])
+              res = xsltApplyStylesheet(cur, doc, params)
+            if res.isNil:
+              stderr.writeLine "failed to apply stylesheet transformation"
+            else:
+              let output = xsltSaveResultToString(res, cur)
+              deallocCStringArray(params)
+              publish(turn, ds, XsltTransform(
+                  stylesheet: stylesheet.value,
+                  input: input.value,
+                  output: xmlDocGetRootElement(res).toPreservesHook,
+                ))
+              xmlFreeDoc(res)
+            xmlFreeDoc(doc)
+          xsltFreeStylesheet(cur)
 
 when isMainModule:
   import syndicate/relays

syndicate_utils.nimble

@@ -1,6 +1,6 @@
 # Package
 
-version = "20240208"
+version = "20240209"
 author        = "Emery Hemingway"
 description   = "Utilites for Syndicated Actors and Synit"
 license       = "unlicense"

tests/xslt.pr

@@ -12,8 +12,51 @@ let ?ds = dataspace
   <xslt { dataspace: $ds }>
 ]
 
+let ?stylesheet = "<?xml version=\"1.0\" encoding=\"UTF-8\"?>
+<xsl:stylesheet xmlns:xsl=\"http://www.w3.org/1999/XSL/Transform\" xmlns=\"http://www.w3.org/1999/xhtml\" version=\"1.0\">
+  <xsl:output method=\"xml\" indent=\"yes\" encoding=\"UTF-8\"/>
+  <xsl:template match=\"/persons\">
+    <html>
+      <head>
+        <title>Testing XML Example</title>
+      </head>
+      <body>
+        <h1>Persons</h1>
+        <ul>
+          <xsl:apply-templates select=\"person\">
+            <xsl:sort select=\"family-name\"/>
+          </xsl:apply-templates>
+        </ul>
+      </body>
+    </html>
+  </xsl:template>
+  <xsl:template match=\"person\">
+    <li>
+      <xsl:value-of select=\"family-name\"/>
+      <xsl:text>, </xsl:text>
+      <xsl:value-of select=\"name\"/>
+    </li>
+  </xsl:template>
+</xsl:stylesheet>
+"
+
+let ?input = "<?xml version=\"1.0\"?>
+<persons>
+  <person username=\"JS1\">
+    <name>John</name>
+    <family-name>Smith</family-name>
+  </person>
+  <person username=\"MI1\">
+    <name>Morka</name>
+    <family-name>Minicus</family-name>
+  </person>
+</persons>
+"
+
 $ds [
-  ? <xslt-transform "/home/emery/src/syndicate_utils/tests/stylesheet.xslt" "/home/emery/src/syndicate_utils/tests/input.xml" ?outputs> [
+
+  ? <xslt-transform $stylesheet $input ?outputs> [
     $log ! <log "-" { xslt-outputs: $outputs }>
   ]
+
 ]