go-ssb-room/web/errors/flashes.go
2021-04-12 14:09:09 +02:00

110 lines
2.5 KiB
Go

package errors
import (
"encoding/gob"
"fmt"
"net/http"
"github.com/gorilla/sessions"
"github.com/ssb-ngi-pointer/go-ssb-room/web/i18n"
)
type FlashHelper struct {
store sessions.Store
locHelper *i18n.Helper
}
func NewFlashHelper(s sessions.Store, loc *i18n.Helper) *FlashHelper {
gob.Register(FlashMessage{})
return &FlashHelper{
store: s,
locHelper: loc,
}
}
const flashSession = "go-ssb-room-flash-messages"
type FlashKind uint
const (
_ FlashKind = iota
// FlashError signals that a problem occured
FlashError
// FlashNotification represents a normal message (like "xyz added/updated successfull")
FlashNotification
)
type FlashMessage struct {
Kind FlashKind
Message string
}
// TODO: rethink error return - maybe panic() / maybe render package?
// AddMessage expects a i18n label, translates it and adds it as a FlashNotification
func (fh FlashHelper) AddMessage(rw http.ResponseWriter, req *http.Request, label string) {
session, err := fh.store.Get(req, flashSession)
if err != nil {
panic(fmt.Errorf("flashHelper: failed to get session: %w", err))
}
ih := fh.locHelper.FromRequest(req)
session.AddFlash(FlashMessage{
Kind: FlashNotification,
Message: ih.LocalizeSimple(label),
})
if err := session.Save(req, rw); err != nil {
panic(fmt.Errorf("flashHelper: failed to save session: %w", err))
}
}
// AddError adds a FlashError and translates the passed err using localizeError()
func (fh FlashHelper) AddError(rw http.ResponseWriter, req *http.Request, err error) {
session, getErr := fh.store.Get(req, flashSession)
if getErr != nil {
panic(fmt.Errorf("flashHelper: failed to get session: %w", err))
}
ih := fh.locHelper.FromRequest(req)
_, msg := localizeError(ih, err)
session.AddFlash(FlashMessage{
Kind: FlashError,
Message: msg,
})
if err := session.Save(req, rw); err != nil {
panic(fmt.Errorf("flashHelper: failed to save session: %w", err))
}
}
// GetAll returns all the FlashMessages, emptys and updates the store
func (fh FlashHelper) GetAll(rw http.ResponseWriter, req *http.Request) ([]FlashMessage, error) {
session, err := fh.store.Get(req, flashSession)
if err != nil {
return nil, err
}
opaqueFlashes := session.Flashes()
flashes := make([]FlashMessage, len(opaqueFlashes))
for i, of := range opaqueFlashes {
f, ok := of.(FlashMessage)
if !ok {
return nil, fmt.Errorf("GetFlashes: failed to unpack flash: %T", of)
}
flashes[i].Kind = f.Kind
flashes[i].Message = f.Message
}
err = session.Save(req, rw)
return flashes, err
}