perkeep/pkg/server/help.go

183 lines
5.9 KiB
Go

/*
Copyright 2015 The Perkeep 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"
"errors"
"fmt"
"html/template"
"net/http"
"strconv"
"strings"
"go4.org/jsonconfig"
"perkeep.org/internal/httputil"
"perkeep.org/pkg/blobserver"
"perkeep.org/pkg/types/clientconfig"
)
const helpHTML string = `<html>
<head>
<title>Help</title>
</head>
<body>
<h2>Help</h2>
<h3>Web User Interface</h3>
<p><a href='https://perkeep.org/doc/search-ui'>Search bar predicates.</a></p>
<h3>Client tools</h3>
<p>
You can download the Perkeep command line tools for Linux, Mac, and Windows at:
<ul>
<li><a href="https://perkeep.org/download">perkeep.org/download</a></li>
</ul>
</p>
<p>You will need to use the following <a href='https://perkeep.org/doc/client-config'>client configuration</a> in order to access this server using the command line tools.</p>
<pre>{{ .ClientConfigJSON }}</pre>
{{ .SecringDownloadHint }}
<h3>Anything Else?</h3>
<p>See the Perkeep <a href='https://perkeep.org/doc/'>online documentation</a> and <a href='https://perkeep.org/community'>community contacts</a>.</p>
</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
serverSecRing string
}
// 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) {
if hh.serverConfig == nil {
hh.serverConfig = config
}
}
func init() {
blobserver.RegisterHandlerConstructor("help", newHelpFromConfig)
}
// fixServerInConfig checks if cc contains a meaningful server (for a client).
// If not, a newly allocated clone of cc is returned, except req.Host is used for
// the hostname of the server. Otherwise, cc is returned.
func fixServerInConfig(cc *clientconfig.Config, req *http.Request) (*clientconfig.Config, error) {
if cc == nil {
return nil, errors.New("nil client config")
}
if len(cc.Servers) == 0 || cc.Servers["default"] == nil || cc.Servers["default"].Server == "" {
return nil, errors.New("no Server in client config")
}
listen := strings.TrimPrefix(strings.TrimPrefix(cc.Servers["default"].Server, "http://"), "https://")
if !(strings.HasPrefix(listen, "0.0.0.0") || strings.HasPrefix(listen, ":")) {
return cc, nil
}
newCC := *cc
server := newCC.Servers["default"]
if req.TLS != nil {
server.Server = "https://" + req.Host
} else {
server.Server = "http://" + req.Host
}
newCC.Servers["default"] = server
return &newCC, nil
}
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
hh.serverSecRing = clientConfig.IdentitySecretRing
clientConfig.IdentitySecretRing = "/home/you/.config/perkeep/identity-secring.gpg"
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 "":
cc, err := fixServerInConfig(hh.clientConfig, req)
if err != nil {
httputil.ServeError(rw, req, err)
return
}
if clientConfig := req.FormValue("clientConfig"); clientConfig != "" {
if clientConfigOnly, err := strconv.ParseBool(clientConfig); err == nil && clientConfigOnly {
httputil.ReturnJSON(rw, cc)
return
}
}
hh.serveHelpHTML(cc, rw, req)
default:
http.Error(rw, "Illegal help path.", http.StatusNotFound)
}
}
func (hh *HelpHandler) serveHelpHTML(cc *clientconfig.Config, rw http.ResponseWriter, req *http.Request) {
jsonBytes, err := json.MarshalIndent(cc, "", " ")
if err != nil {
httputil.ServeError(rw, req, fmt.Errorf("could not serialize client config JSON: %v", err))
return
}
var hint template.HTML
if strings.HasPrefix(hh.serverSecRing, "/gcs/") {
bucketdir := strings.TrimPrefix(hh.serverSecRing, "/gcs/")
bucketdir = strings.TrimSuffix(bucketdir, "/identity-secring.gpg")
hint = template.HTML(fmt.Sprintf("<p>Download your GnuPG secret ring from <a href=\"https://console.developers.google.com/storage/browser/%s/\">https://console.developers.google.com/storage/browser/%s/</a> and place it in your <a href='https://perkeep.org/doc/client-config'>Perkeep client config directory</a>. Keep it private. It's not encrypted or password-protected and anybody in possession of it can create Perkeep claims as your identity.</p>\n",
bucketdir, bucketdir))
}
hh.goTemplate.Execute(rw, struct {
ClientConfigJSON string
SecringDownloadHint template.HTML
}{
ClientConfigJSON: string(jsonBytes),
SecringDownloadHint: hint,
})
}