utils.go

//
//  tank
//
//  Import and Playlist Daemon for autoradio project
//
//
//  Copyright (C) 2017-2019 Christian Pointner <equinox@helsinki.at>
//
//  This file is part of tank.
//
//  tank is free software: you can redistribute it and/or modify
//  it under the terms of the GNU General Public License as published by
//  the Free Software Foundation, either version 3 of the License, or
//  any later version.
//
//  tank is distributed in the hope that it will be useful,
//  but WITHOUT ANY WARRANTY; without even the implied warranty of
//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
//  GNU General Public License for more details.
//
//  You should have received a copy of the GNU General Public License
//  along with tank. If not, see <http://www.gnu.org/licenses/>.
//

package v1

import (
	"net/http"
	"strconv"

	"github.com/gin-gonic/gin"
	"gitlab.servus.at/autoradio/tank/auth"
	"gitlab.servus.at/autoradio/tank/importer"
	"gitlab.servus.at/autoradio/tank/store"
)

func idFromString(s string) (uint64, error) {
	return strconv.ParseUint(s, 10, 64)
}

func statusCodeFromError(err error) (code int, response ErrorResponse) {
	code = http.StatusInternalServerError
	response = ErrorResponse{Error: err.Error()}

	switch err.(type) {
	case *store.ErrFileInUse:
		code = http.StatusConflict
		response.Detail = err
	case store.ErrInvalidMetadataField:
		code = http.StatusBadRequest
	case *importer.JobSourceResult:
		response.Detail = err.(*importer.JobSourceResult).Log
	default:
		switch err {
		case ErrNotFlowJSUpload:
			code = http.StatusConflict
		case ErrFlowJSChunkAlreadUploading:
			code = http.StatusConflict
		case ErrFileVanished:
			code = http.StatusConflict

		case store.ErrNotImplemented:
			code = http.StatusNotImplemented
		case store.ErrNotFound:
			code = http.StatusNotFound
		case store.ErrFileNotNew:
			code = http.StatusConflict
		case store.ErrFileImportNotDone:
			code = http.StatusConflict

		case importer.ErrNotImplemented:
			code = http.StatusNotImplemented
		case importer.ErrNotFound:
			code = http.StatusNotFound
		case importer.ErrSourceNotSupported:
			code = http.StatusBadRequest
		case importer.ErrImportNotRunning:
			code = http.StatusConflict
		case importer.ErrSourceAlreadyAttached:
			code = http.StatusConflict
		case importer.ErrSourceNotYetAttached:
			code = http.StatusConflict
		case importer.ErrSourceNotAUpload:
			code = http.StatusConflict
		case importer.ErrTooManyJobs:
			code = http.StatusTooManyRequests
		case importer.ErrAlreadyCanceled:
			code = http.StatusConflict
		}
	}
	return
}

func sendError(c *gin.Context, err error) {
	code, response := statusCodeFromError(err)
	c.JSON(code, response)
}

func getAuthSession(r *http.Request) *auth.Session {
	s, ok := auth.SessionFromRequest(r)
	if !ok || s == nil {
		panic("no session attached to request - is the auth middleware installed?")
	}
	return s
}

func authorizeRequest(c *gin.Context, showID string) (bool, *auth.Session) {
	s := getAuthSession(c.Request)
	if s.ReadOnly {
		switch c.Request.Method {
		case http.MethodGet:
			break
		default:
			c.JSON(http.StatusForbidden, ErrorResponse{Error: "this session is read-only"})
			return false, s
		}
	}
	if s.AllShows {
		return true, s
	}
	for _, show := range s.Shows {
		if show == showID {
			return true, s
		}
	}
	c.JSON(http.StatusForbidden, ErrorResponse{Error: "you are not allowed to access show: " + showID})
	return false, s
}