From 60ed522bc8287e4eb9434e3567b31b130bec47f7 Mon Sep 17 00:00:00 2001
From: brent s <bts@square-r00t.net>
Date: Sat, 12 Sep 2020 01:25:44 -0400
Subject: [PATCH] checking in some various work

---
 conf.go   |  31 +++++++++++++
 const.go  |   6 +++
 schema.go | 131 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 168 insertions(+)
 create mode 100644 conf.go
 create mode 100644 const.go
 create mode 100644 schema.go

diff --git a/conf.go b/conf.go
new file mode 100644
index 0000000..7530ce7
--- /dev/null
+++ b/conf.go
@@ -0,0 +1,31 @@
+package conf
+
+import (
+	"encoding/xml"
+	`fmt`
+	"io/ioutil"
+
+	`github.com/pkg/errors`
+
+	"git.square-r00t.net/go_sysutils.git/paths"
+)
+
+// ParseConf parses the path of the XML config provided at confPath ptr by using the confStruct struct ptr.
+// If an XSD is found in the struct, it will be validated against (returning pass/fail as bool), otherwise always return true unless error.
+func ParseConf(confPath *string, confStruct *struct{}) (bool, error) {
+	exists, err := paths.RealPathExists(confPath)
+	if !exists {
+		return false, errors.New(fmt.Sprintf("Configuration path %v does not exist", *confPath))
+	} else if err != nil {
+		return false, err
+	}
+	xmlDoc, err := ioutil.ReadFile(*confPath)
+	if err != nil {
+		return false, err
+	}
+	err = xml.Unmarshal(xmlDoc, confStruct)
+	if err != nil {
+		return false, err
+	}
+
+}
\ No newline at end of file
diff --git a/const.go b/const.go
new file mode 100644
index 0000000..742d6b8
--- /dev/null
+++ b/const.go
@@ -0,0 +1,6 @@
+package conf
+
+const (
+	XSIVal = "http://www.w3.org/2001/XMLSchema-instance"
+	DefSchemaNS = "xsi"
+)
diff --git a/schema.go b/schema.go
new file mode 100644
index 0000000..386cf0f
--- /dev/null
+++ b/schema.go
@@ -0,0 +1,131 @@
+package conf
+
+// The usage of this depends on the successful resolution of https://github.com/lestrrat-go/libxml2/issues/67.
+
+import (
+	`errors`
+	`io/ioutil`
+	`net/http`
+	`regexp`
+	`strings`
+
+	lxml `github.com/lestrrat-go/libxml2`
+	lxmlp `github.com/lestrrat-go/libxml2/parser`
+	lxmlt `github.com/lestrrat-go/libxml2/types`
+	`github.com/lestrrat-go/libxml2/xsd`
+
+	rpaths `r00t2.io/sysutils/paths`
+)
+
+var uriRe = regexp.MustCompile(`^(?P<type>file|https?)://(?P<path>.+)$`)
+
+type NSXML struct {
+	XML       *[]byte        // The raw XML bytes.
+	LXML      lxmlt.Document // The lxml.Parse()'d XML.
+	Root      lxmlt.Element  // The Document's root element
+	XSD       xsd.Schema // Its schema.
+}
+
+func (x *NSXML) Validate(defaults bool) (bool, error) {
+	// We need the XSD before we can validate.
+	if err := x.getXSD(); err != nil {
+		return false, err
+	}
+
+	return false, nil
+}
+
+func (x *NSXML) getXSD() error {
+	if err := x.mapNS(); err != nil {
+		return err
+	}
+	r := uriRe.FindStringSubmatch(strings.ToLower(x.XSDPath))
+	reResults := make(map[string]string)
+	for i, name := range uriRe.SubexpNames() {
+		if i != 0 && name != "" {
+			reResults[name] = r[i]
+		}
+	}
+	var xsdRaw []byte
+	switch reResults["type"] {
+	case "file":
+		p := reResults["path"]
+		exists, err := rpaths.RealPathExists(&p)
+		if (err != nil) || (!exists) {
+			return err
+		}
+		xsdRaw, err = ioutil.ReadFile(p)
+		if err != nil {
+			return err
+		}
+	case "http", "https":
+		resp, err := http.Get(x.XSDPath)
+		if err != nil {
+			return err
+		}
+		defer resp.Body.Close()
+		xsdRaw, err = ioutil.ReadAll(resp.Body)
+		if err != nil {
+			return err
+		}
+	default:
+		return errors.New("invalid URI type for schemaLocation")
+	}
+	x.XSD, err = xsd.Parse(xsdRaw)
+	if err != nil {
+		return err
+	}
+}
+
+// mapNS (tries to) extract the default namespace from the document via the SchemaLocation property of XML, sets DefaultNS,
+// and then gets the XSDPath specified therein.
+func (x *NSXML) mapNS() error {
+	if x.XSD.Pointer() != 0 {
+		// Already set.
+		return nil
+	}
+	if err := x.parse(); err != nil {
+		return err
+	}
+
+	x.DefaultNS = x.Root.NamespaceURI()
+	/* x.DefaultNS = *x.XML.XMLName.Space
+	sl := *x.XML.SchemaLocation
+	*/
+	ns := strings.Fields(sl)
+	if ns != nil {
+		if len(ns) > 2 {
+			return errors.New("too many values for a valid schemaLocation")
+		} else if len(ns) == 0 {
+			return errors.New("no specified value for schemaLocation")
+		} else if len(ns) == 1 {
+			// LAZY. This is improper XML, but is commonly used regardless.
+			x.XSDPath = ns[0]
+		} else {
+			if ns[0] == x.DefaultNS {
+				x.XSDPath = ns[1]
+			}
+		}
+	}
+	return nil
+}
+
+// parse parses the x.XML into its x.LXML
+func (x *NSXML) parse() error {
+	if x.LXML != nil {
+		return nil // Already parsed
+	}
+	if x.XML == nil {
+		return errors.New("XML property is empty")
+	}
+	x.LXML, err = lxml.Parse(*x.XML, lxmlp.XMLParseBigLines, lxmlp.XMLParseXInclude)
+	if err != nil {
+		return err
+	}
+	de, err := x.LXML.DocumentElement()
+	if err != nil {
+		return err
+	}
+	x.Root = de.(lxmlt.Element)
+	return nil
+}