func (app *App) addAssetsManager(manager *assets.Manager, main bool) {
handler := HandlerFromHTTPFunc(manager.Handler())
app.Handle("^"+manager.Prefix(), handler)
if main {
app.Handle("^/favicon.ico$", handler)
app.Handle("^/robots.txt$", handler)
}
}
func executeAsset(t *Template, p *Template, vars VarMap, m *assets.Manager, asset *assets.Asset) (string, error) {
name := asset.TemplateName()
log.Debugf("executing asset template %s (from %s)", name, t.name)
tmpl := New(m.VFS(), nil)
tmpl.addFuncMap(t.funcMap, true)
if p != nil {
tmpl.addFuncMap(p.funcMap, true)
}
if err := tmpl.Parse(name); err != nil {
return "", err
}
if err := tmpl.Compile(); err != nil {
return "", err
}
if p != nil && p != t {
ns := t.namespaceIn(p)
if ns != "" {
vars = vars.unpack(ns)
}
}
var buf bytes.Buffer
if err := tmpl.ExecuteContext(&buf, nil, nil, vars); err != nil {
return "", err
}
f, err := m.Load(name)
if err != nil {
return "", err
}
h := fnv.New32a()
// Writing to a hash.Hash never fails
// Include the initial and the final
// asset in the hash.
io.Copy(h, f)
f.Close()
h.Write(buf.Bytes())
hash := hex.EncodeToString(h.Sum(nil))
ext := path.Ext(name)
nonExt := name[:len(name)-len(ext)]
out := fmt.Sprintf("%s.gen.%s%s", nonExt, hash, ext)
// Check if the file already exists and has the same
// contents. This prevents failures when runnin on
// App Engine, since writes are not allowed.
if prev, err := m.Load(out); err == nil {
defer prev.Close()
if data, err := ioutil.ReadAll(prev); err == nil {
if bytes.Equal(data, buf.Bytes()) {
// File already up to date
return out, nil
}
}
}
w, err := m.Create(out, true)
if err != nil {
return "", err
}
if _, err := w.Write(buf.Bytes()); err != nil {
return "", err
}
if err := w.Close(); err != nil {
return "", err
}
return out, nil
}