2015-02-21 12:22:11 +00:00
/ *
Copyright 2015 The Camlistore Authors .
Licensed under the Apache License , Version 2.0 ( the "License" ) ;
you may not use this file except in compliance with the License .
You may obtain a copy of the License at
http : //www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing , software
distributed under the License is distributed on an "AS IS" BASIS ,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND , either express or implied .
See the License for the specific language governing permissions and
limitations under the License .
* /
package server
import (
"encoding/json"
"fmt"
"html/template"
"net/http"
"sync"
"camlistore.org/pkg/blobserver"
"camlistore.org/pkg/httputil"
"camlistore.org/pkg/jsonconfig"
"camlistore.org/pkg/types/clientconfig"
)
const helpHTML string = ` < html >
< head >
< title > Help < / title >
< / head >
< body >
< h2 > Help < / h2 >
2015-06-29 15:54:17 +00:00
< h3 > Web User Interface < / h3 >
< p > < a href = ' https : //camlistore.googlesource.com/camlistore/+/master/doc/search-ui.txt'>Search bar predicates.</a></p>
2015-02-21 12:22:11 +00:00
< h3 > Client Configuration < / h3 >
< p > You will need to use the following < a href = ' http : //camlistore.org/docs/client-config'>client configuration</a> in order to access this server using the Camlistore command line tools.</p>
< pre > { { . } } < / pre >
2015-06-29 15:54:17 +00:00
< h3 > Anything Else ? < / h3 >
< p > See the Camlistore < a href = ' http : //camlistore.org/docs/'>online documentation</a> and <a href='http://camlistore.org/community/'>community contacts</a>.</p>
2015-02-21 12:22:11 +00:00
< / body >
< / html > `
// HelpHandler publishes information related to accessing the server
type HelpHandler struct {
clientConfig * clientconfig . Config // generated from serverConfig
serverConfig jsonconfig . Obj // low-level config
goTemplate * template . Template // for rendering
}
// setServerConfigOnce guards operation within SetServerConfig
var setServerConfigOnce sync . Once
// SetServerConfig enables the handler to receive the server config
// before InitHandler, which generates a client config from the server config, is called.
func ( hh * HelpHandler ) SetServerConfig ( config jsonconfig . Obj ) {
setServerConfigOnce . Do ( func ( ) { hh . serverConfig = config } )
}
func init ( ) {
blobserver . RegisterHandlerConstructor ( "help" , newHelpFromConfig )
}
func ( hh * HelpHandler ) InitHandler ( hl blobserver . FindHandlerByTyper ) error {
if hh . serverConfig == nil {
return fmt . Errorf ( "HelpHandler's serverConfig must be set before calling its InitHandler" )
}
clientConfig , err := clientconfig . GenerateClientConfig ( hh . serverConfig )
if err != nil {
return fmt . Errorf ( "error generating client config: %v" , err )
}
hh . clientConfig = clientConfig
tmpl , err := template . New ( "help" ) . Parse ( helpHTML )
if err != nil {
return fmt . Errorf ( "error creating template: %v" , err )
}
hh . goTemplate = tmpl
return nil
}
func newHelpFromConfig ( ld blobserver . Loader , conf jsonconfig . Obj ) ( h http . Handler , err error ) {
return & HelpHandler { } , nil
}
func ( hh * HelpHandler ) ServeHTTP ( rw http . ResponseWriter , req * http . Request ) {
suffix := httputil . PathSuffix ( req )
if ! httputil . IsGet ( req ) {
http . Error ( rw , "Illegal help method." , http . StatusMethodNotAllowed )
return
}
switch suffix {
case "" :
hh . serveHelpHTML ( rw , req )
default :
http . Error ( rw , "Illegal help path." , http . StatusNotFound )
}
}
func ( hh * HelpHandler ) serveHelpHTML ( rw http . ResponseWriter , req * http . Request ) {
jsonBytes , err := json . MarshalIndent ( hh . clientConfig , "" , " " )
if err != nil {
httputil . ServeError ( rw , req , fmt . Errorf ( "could not serialize client config JSON: %v" , err ) )
return
}
hh . goTemplate . Execute ( rw , string ( jsonBytes ) )
}
