Add a transform step

This allows for the manipulation of the DOM.  This is expected to be
applied after the templates are rendered.
This commit is contained in:
Noah Campbell 2013-09-17 13:04:28 -07:00
parent c75da346e1
commit c6fe87b14e
2 changed files with 87 additions and 0 deletions

46
transform/post.go Normal file
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package transform
import (
"io"
"net/url"
htmltran "code.google.com/p/go-html-transform/html/transform"
)
type Transformer struct {
BaseURL string
}
func (t *Transformer) Apply(r io.Reader, w io.Writer) (err error) {
var tr *htmltran.Transformer
if tr, err = htmltran.NewFromReader(r); err != nil {
return
}
if err = t.absUrlify(tr); err != nil {
return
}
return tr.Render(w)
}
func (t *Transformer) absUrlify(tr *htmltran.Transformer) (err error) {
var baseURL, inURL *url.URL
if baseURL, err = url.Parse(t.BaseURL); err != nil {
return
}
replace := func(in string) string {
if inURL, err = url.Parse(in); err != nil {
return in + "?"
}
return baseURL.ResolveReference(inURL).String()
}
if err = tr.Apply(htmltran.TransformAttrib("src", replace), "script"); err != nil {
return
}
return tr.Apply(htmltran.TransformAttrib("href", replace), "a")
}

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package transform
import (
"testing"
"strings"
"bytes"
)
const H5_JS_CONTENT_DOUBLE_QUOTE = "<!DOCTYPE html><html><head><script src=\"foobar.js\"></script></head><body><nav><h1>title</h1></nav><article>content <a href='/foobar'>foobar</a>. Follow up</article></body></html>"
const H5_JS_CONTENT_SINGLE_QUOTE = "<!DOCTYPE html><html><head><script src='foobar.js'></script></head><body><nav><h1>title</h1></nav><article>content <a href='/foobar'>foobar</a>. Follow up</article></body></html>"
const H5_JS_CONTENT_ABS_URL = "<!DOCTYPE html><html><head><script src=\"http://user@host:10234/foobar.js\"></script></head><body><nav><h1>title</h1></nav><article>content <a href=\"https://host/foobar\">foobar</a>. Follow up</article></body></html>"
// URL doesn't recognize authorities. BUG?
//const H5_JS_CONTENT_ABS_URL = "<!DOCTYPE html><html><head><script src=\"//host/foobar.js\"></script></head><body><nav><h1>title</h1></nav><article>content <a href=\"https://host/foobar\">foobar</a>. Follow up</article></body></html>"
const CORRECT_OUTPUT_SRC_HREF = "<!DOCTYPE html><html><head><script src=\"http://base/foobar.js\"></script></head><body><nav><h1>title</h1></nav><article>content <a href=\"http://base/foobar\">foobar</a>. Follow up</article></body></html>"
func TestAbsUrlify(t *testing.T) {
tests := []struct {
content string
expected string
}{
{H5_JS_CONTENT_DOUBLE_QUOTE, CORRECT_OUTPUT_SRC_HREF},
{H5_JS_CONTENT_SINGLE_QUOTE, CORRECT_OUTPUT_SRC_HREF},
{H5_JS_CONTENT_ABS_URL, H5_JS_CONTENT_ABS_URL},
}
for _, test := range tests {
tr := &Transformer{
BaseURL: "http://base",
}
out := new(bytes.Buffer)
err := tr.Apply(strings.NewReader(test.content), out)
if err != nil {
t.Errorf("Unexpected error: %s", err)
}
if test.expected != string(out.Bytes()) {
t.Errorf("Expected:\n%s\nGot:\n%s", test.expected, string(out.Bytes()))
}
}
}