website: allow HTML in camli errors. use website for client error.

http://camlistore.org/issue/276

Change-Id: I16f139fe2b6f1200250db668fa415ae42ff2c171

pkg/client/client.go

@@ -948,7 +948,7 @@ func (c *Client) signerInit() {
 func (c *Client) buildSigner() (*schema.Signer, error) {
 	c.initSignerPublicKeyBlobrefOnce.Do(c.initSignerPublicKeyBlobref)
 	if !c.signerPublicKeyRef.Valid() {
-		return nil, camtypes.Err("client-no-public-key")
+		return nil, camtypes.ErrClientNoPublicKey
 	}
 	return schema.NewSigner(c.signerPublicKeyRef, strings.NewReader(c.publicKeyArmored), c.SecretRingFile())
 }

pkg/client/config.go

@@ -34,6 +34,7 @@ import (
 	"camlistore.org/pkg/jsonconfig"
 	"camlistore.org/pkg/jsonsign"
 	"camlistore.org/pkg/osutil"
+	"camlistore.org/pkg/types/camtypes"
 	"camlistore.org/pkg/types/clientconfig"
 	"camlistore.org/pkg/wkfs"
 )
@@ -270,7 +271,7 @@ func serverOrDie() string {
 	}
 	server := defaultServer()
 	if server == "" {
-		log.Fatalf("No valid server defined with CAMLI_SERVER, or with -server, or in %q", osutil.UserClientConfigPath())
+		camtypes.ErrClientNoServer.Fatal()
 	}
 	return cleanServer(server)
 }

pkg/types/camtypes/errors.go

@@ -18,16 +18,19 @@ package camtypes
 
 import (
 	"fmt"
+	"log"
+
+	"camlistore.org/pkg/osutil"
 )
 
 //TODO(mpl): move pkg/camerrors stuff in here
 
-var camErrors = map[string]error{}
+var camErrors = map[string]*camErr{}
 
-func init() {
-	// TODO(mpl): set des to be "See http://camlistore.org/err/client-no-public-key"
-	addCamError("client-no-public-key", "No public key configured: see 'camput init'.")
-}
+var (
+	ErrClientNoServer    = addCamError("client-no-server", fmt.Sprintf("No valid server defined. It can be set with the CAMLI_SERVER environment variable, or the --server flag, or in the \"servers\" section of %q (see https://camlistore.org/docs/client-config).", osutil.UserClientConfigPath()))
+	ErrClientNoPublicKey = addCamError("client-no-public-key", "No public key configured: see 'camput init'.")
+)
 
 type camErr struct {
 	key string
@@ -38,6 +41,18 @@ func (ce *camErr) Error() string {
 	return ce.des
 }
 
+func (ce *camErr) Fatal() {
+	log.Fatalf("%v error. See %v", ce.key, ce.URL())
+}
+
+func (ce *camErr) Warn() {
+	log.Printf("%v error. See %v.", ce.key, ce.URL())
+}
+
+func (ce *camErr) URL() string {
+	return fmt.Sprintf("https://camlistore.org/err/%s", ce.key)
+}
+
 // Err returns the error registered for key.
 // It panics for an unregistered key.
 func Err(key string) error {
@@ -48,9 +63,14 @@ func Err(key string) error {
 	return v
 }
 
-func addCamError(key, des string) {
-	camErrors[key] = &camErr{
+func addCamError(key, des string) *camErr {
+	if e, ok := camErrors[key]; ok {
+		panic(fmt.Sprintf("error %v already registered as %q", key, e.Error()))
+	}
+	e := &camErr{
 		key: key,
 		des: des,
 	}
+	camErrors[key] = e
+	return e
 }

website/camweb.go

@@ -465,7 +465,12 @@ func ipHandler(w http.ResponseWriter, r *http.Request) {
 	w.Write([]byte(str))
 }
 
-const errPattern = "/err/"
+const (
+	errPattern  = "/err/"
+	toHyperlink = `<a href="$1$2">$1$2</a>`
+)
+
+var camliURLPattern = regexp.MustCompile(`(https?://camlistore.org)([a-zA-Z0-9\-\_/]+)?`)
 
 func errHandler(w http.ResponseWriter, r *http.Request) {
 	errString := strings.TrimPrefix(r.URL.Path, errPattern)
@@ -478,10 +483,10 @@ func errHandler(w http.ResponseWriter, r *http.Request) {
 	err := camtypes.Err(errString)
 	data := struct {
 		Code        string
-		Description string
+		Description template.HTML
 	}{
 		Code:        errString,
-		Description: err.Error(),
+		Description: template.HTML(camliURLPattern.ReplaceAllString(err.Error(), toHyperlink)),
 	}
 	contents := applyTemplate(camliErrorHTML, "camliErrorHTML", data)
 	w.WriteHeader(http.StatusFound)