Merge pull request #4 from mcnijman/master

Fix #3: fatal stack overflow

README.md

@@ -1,4 +1,5 @@
 # microdata
+
 A microdata parser in Go
 
 See [http://www.w3.org/TR/microdata/](http://www.w3.org/TR/microdata/) for more information about Microdata
@@ -13,20 +14,20 @@ Simply run
 
 Documentation is at [http://godoc.org/github.com/iand/microdata](http://godoc.org/github.com/iand/microdata)
 
-
 ## Usage
 
 Example of parsing a string containing HTML:
 
-	package main
+```go
+package main
 
-	import (
+import (
     "github.com/iand/microdata"
     "net/url"
     "strings"
-	)
+)
 
-	func main() {
+func main() {
     html := `<div itemscope>
         <p>My name is <span itemprop="name">Elizabeth</span>.</p>
     </div>`
@@ -40,13 +41,15 @@ Example of parsing a string containing HTML:
     }
 
     println("Name: ", data.Items[0].Properties["name"][0].(string))
-	}
+}
+```
 
 Extract microdata from a webpage and print the result as JSON
 
-	package main
+```go
+package main
 
-	import (
+import (
     "bytes"
     "io/ioutil"
     "net/http"
@@ -54,9 +57,9 @@ Extract microdata from a webpage and print the result as JSON
     "os"
 
     "github.com/iand/microdata"
-	)
+)
 
-	func main() {
+func main() {
 
     baseUrl, _ := url.Parse("http://www.designhive.com/blog/using-schemaorg-microdata")
 
@@ -71,17 +74,15 @@ Extract microdata from a webpage and print the result as JSON
 
     json, _ := data.JSON()
     os.Stdout.Write(json)
-	}
+}
-
+```
 
 ## Authors
 
 * [Ian Davis](http://github.com/iand) - <http://iandavis.com/>
 
-
 ## Contributors
 
-
 ## Contributing
 
 * Do submit your changes as a pull request

microdata.go

@@ -18,12 +18,12 @@ import (
 	"golang.org/x/net/html/atom"
 )
 
-type ValueList []interface{}
+type valueList []interface{}
-type PropertyMap map[string]ValueList
+type propertyMap map[string]valueList
 
 // Item represents a microdata item
 type Item struct {
-	Properties PropertyMap `json:"properties"`
+	Properties propertyMap `json:"properties"`
 	Types      []string    `json:"type,omitempty"`
 	ID         string      `json:"id,omitempty"`
 }
@@ -31,7 +31,7 @@ type Item struct {
 // NewItem creates a new microdata item
 func NewItem() *Item {
 	return &Item{
-		Properties: make(PropertyMap, 0),
+		Properties: make(propertyMap, 0),
 		Types:      make([]string, 0),
 	}
 }
@@ -132,11 +132,10 @@ func (p *Parser) Parse() (*Microdata, error) {
 			}
 			// itemid only valid when itemscope and itemtype are both present
 			if itemid, exists := getAttr("itemid", node); exists {
-				if parsedUrl, err := p.base.Parse(itemid); err == nil {
+				if parsedURL, err := p.base.Parse(itemid); err == nil {
-					item.ID = parsedUrl.String()
+					item.ID = parsedURL.String()
 				}
 			}
-
 		}
 
 		if itemrefs, exists := getAttr("itemref", node); exists {
@@ -168,10 +167,12 @@ func (p *Parser) readItem(item *Item, node *html.Node) {
 					itemref = strings.TrimSpace(itemref)
 
 					if refnode, exists := p.identifiedNodes[itemref]; exists {
+						if refnode != node {
 							p.readItem(subitem, refnode)
 						}
 					}
 				}
+			}
 
 			for child := node.FirstChild; child != nil; {
 				p.readItem(subitem, child)
@@ -198,15 +199,14 @@ func (p *Parser) readItem(item *Item, node *html.Node) {
 			}
 		case atom.Audio, atom.Embed, atom.Iframe, atom.Img, atom.Source, atom.Track, atom.Video:
 			if urlValue, exists := getAttr("src", node); exists {
-				if parsedUrl, err := p.base.Parse(urlValue); err == nil {
+				if parsedURL, err := p.base.Parse(urlValue); err == nil {
-					propertyValue = parsedUrl.String()
+					propertyValue = parsedURL.String()
 				}
-
 			}
 		case atom.A, atom.Area, atom.Link:
 			if urlValue, exists := getAttr("href", node); exists {
-				if parsedUrl, err := p.base.Parse(urlValue); err == nil {
+				if parsedURL, err := p.base.Parse(urlValue); err == nil {
-					propertyValue = parsedUrl.String()
+					propertyValue = parsedURL.String()
 				}
 			}
 		case atom.Object:

microdata_test.go

@@ -8,6 +8,7 @@ package microdata
 import (
 	"bytes"
 	"net/url"
+	"reflect"
 	"strings"
 	"testing"
 )
@@ -569,3 +570,30 @@ func TestJsonWithType(t *testing.T) {
 		t.Errorf("Expecting %s but got %s", expected, actual)
 	}
 }
+
+// This test checks stack overflow doesn't happen as mentioned in
+// https://github.com/iand/microdata/issues/3
+func TestSkipSelfReferencingItemref(t *testing.T) {
+	html := `<body itemscope itemtype="http://schema.org/WebPage">
+	  <span id="1" itemscope itemtype="http://data-vocabulary.org/Breadcrumb" itemprop="child" itemref="1">
+	    <a title="Foo" itemprop="url" href="/foo/bar"><span itemprop="title">Foo</span></a>
+	  </span>
+	</body>`
+
+	actual := ParseData(html, t)
+
+	child := NewItem()
+	child.AddString("title", "Foo")
+	child.AddString("url", "http://example.com/foo/bar")
+
+	item := NewItem()
+	item.AddType("http://schema.org/WebPage")
+	item.AddItem("child", child)
+
+	expected := NewMicrodata()
+	expected.AddItem(item)
+
+	if !reflect.DeepEqual(expected, actual) {
+		t.Errorf("Expecting %s but got %s", expected, actual)
+	}
+}