// Calls the JS sync function to assign the doc to channels, grant users
// access to channels, and reject invalid documents.
func (db *Database) getChannelsAndAccess(doc *document, body Body, parentRevID string) (result base.Set, access channels.AccessMap, roles channels.AccessMap, err error) {
base.LogTo("CRUD+", "Invoking sync on doc %q rev %s", doc.ID, body["_rev"])
// Get the parent revision, to pass to the sync function:
var oldJson string
if parentRevID != "" {
var oldJsonBytes []byte
oldJsonBytes, err = db.getRevisionJSON(doc, parentRevID)
if err != nil {
if base.IsDocNotFoundError(err) {
err = nil
}
return
}
oldJson = string(oldJsonBytes)
}
if db.ChannelMapper != nil {
// Call the ChannelMapper:
var output *channels.ChannelMapperOutput
output, err = db.ChannelMapper.MapToChannelsAndAccess(body, oldJson,
makeUserCtx(db.user))
if err == nil {
result = output.Channels
access = output.Access
roles = output.Roles
err = output.Rejection
if err != nil {
base.Log("Sync fn rejected: new=%+v old=%s --> %s", body, oldJson, err)
} else if !validateAccessMap(access) || !validateRoleAccessMap(roles) {
err = base.HTTPErrorf(500, "Error in JS sync function")
}
} else {
base.Warn("Sync fn exception: %+v; doc = %s", err, body)
err = base.HTTPErrorf(500, "Exception in JS sync function")
}
} else {
// No ChannelMapper so by default use the "channels" property:
value, _ := body["channels"].([]interface{})
if value != nil {
array := make([]string, 0, len(value))
for _, channel := range value {
channelStr, ok := channel.(string)
if ok && len(channelStr) > 0 {
array = append(array, channelStr)
}
}
result, err = channels.SetFromArray(array, channels.KeepStar)
}
}
return
}
// Top-level handler for _changes feed requests.
func (h *handler) handleChanges() error {
// http://wiki.apache.org/couchdb/HTTP_database_API#Changes
// http://docs.couchdb.org/en/latest/api/database/changes.html
var options db.ChangesOptions
options.Since = channels.TimedSetFromString(h.getQuery("since"))
options.Limit = int(h.getIntQuery("limit", 0))
options.Conflicts = (h.getQuery("style") == "all_docs")
options.IncludeDocs = (h.getBoolQuery("include_docs"))
options.Terminator = make(chan bool)
defer close(options.Terminator)
// Get the channels as parameters to an imaginary "bychannel" filter.
// The default is all channels the user can access.
userChannels := channels.SetOf("*")
filter := h.getQuery("filter")
if filter != "" {
if filter != "sync_gateway/bychannel" {
return base.HTTPErrorf(http.StatusBadRequest, "Unknown filter; try sync_gateway/bychannel")
}
channelsParam := h.getQuery("channels")
if channelsParam == "" {
return base.HTTPErrorf(http.StatusBadRequest, "Missing 'channels' filter parameter")
}
var err error
userChannels, err = channels.SetFromArray(strings.Split(channelsParam, ","),
channels.ExpandStar)
if err != nil {
return err
}
if len(userChannels) == 0 {
return base.HTTPErrorf(http.StatusBadRequest, "Empty channel list")
}
}
h.db.ChangesClientStats.Increment()
defer h.db.ChangesClientStats.Decrement()
switch h.getQuery("feed") {
case "normal", "":
return h.sendSimpleChanges(userChannels, options)
case "longpoll":
options.Wait = true
return h.sendSimpleChanges(userChannels, options)
case "continuous":
return h.sendContinuousChangesByHTTP(userChannels, options)
case "websocket":
return h.sendContinuousChangesByWebSocket(userChannels, options)
default:
return base.HTTPErrorf(http.StatusBadRequest, "Unknown feed type")
}
}
func (h *handler) sendContinuousChangesByWebSocket(inChannels base.Set, options db.ChangesOptions) error {
handler := func(conn *websocket.Conn) {
h.logStatus(101, "Upgraded to WebSocket protocol")
defer func() {
conn.Close()
base.LogTo("HTTP+", "#%03d: --> WebSocket closed", h.serialNumber)
}()
// Read changes-feed options from an initial incoming WebSocket message in JSON format:
if msg, err := readWebSocketMessage(conn); err != nil {
return
} else {
var channelNames []string
var err error
if _, options, _, channelNames, err = readChangesOptionsFromJSON(msg); err != nil {
return
}
if channelNames != nil {
inChannels, _ = channels.SetFromArray(channelNames, channels.ExpandStar)
}
}
options.Terminator = make(chan bool)
defer close(options.Terminator)
caughtUp := false
h.generateContinuousChanges(inChannels, options, func(changes []*db.ChangeEntry) error {
var data []byte
if changes != nil {
data, _ = json.Marshal(changes)
} else if !caughtUp {
caughtUp = true
data, _ = json.Marshal([]*db.ChangeEntry{})
} else {
data = []byte{}
}
_, err := conn.Write(data)
return err
})
}
server := websocket.Server{
Handshake: func(*websocket.Config, *http.Request) error { return nil },
Handler: handler,
}
server.ServeHTTP(h.response, h.rq)
return nil
}
// Calls the JS sync function to assign the doc to channels, grant users
// access to channels, and reject invalid documents.
func (db *Database) getChannelsAndAccess(doc *document, body Body, parentRevID string) (result channels.Set, access channels.AccessMap, err error) {
base.LogTo("CRUD", "Invoking sync on doc %q rev %s", doc.ID, body["_rev"])
var oldJson string
if parentRevID != "" {
oldJson = string(doc.getRevisionJSON(parentRevID))
}
if db.ChannelMapper != nil {
var output *channels.ChannelMapperOutput
output, err = db.ChannelMapper.MapToChannelsAndAccess(body, oldJson,
makeUserCtx(db.user))
if err == nil {
result = output.Channels
access = output.Access
err = output.Rejection
if err != nil {
base.Log("Sync fn rejected: new=%+v old=%s --> %s", body, oldJson, err)
} else if !validateAccessMap(access) {
err = &base.HTTPError{500, fmt.Sprintf("Error in JS sync function")}
}
} else {
base.Warn("Sync fn exception: %+v; doc = %s", err, body)
err = &base.HTTPError{500, "Exception in JS sync function"}
}
} else {
// No ChannelMapper so by default use the "channels" property:
value, _ := body["channels"].([]interface{})
if value != nil {
array := make([]string, 0, len(value))
for _, channel := range value {
channelStr, ok := channel.(string)
if ok && len(channelStr) > 0 {
array = append(array, channelStr)
}
}
result, err = channels.SetFromArray(array, channels.KeepStar)
}
}
return
}
func (h *handler) handleChanges() error {
// http://wiki.apache.org/couchdb/HTTP_database_API#Changes
var options db.ChangesOptions
options.Since = h.getIntQuery("since", 0)
options.Limit = int(h.getIntQuery("limit", 0))
options.Conflicts = (h.getQuery("style") == "all_docs")
options.IncludeDocs = (h.getBoolQuery("include_docs"))
// Get the channels as parameters to an imaginary "bychannel" filter.
// The default is all channels the user can access.
userChannels := channels.SetOf("*")
filter := h.getQuery("filter")
if filter != "" {
if filter != "sync_gateway/bychannel" {
return &base.HTTPError{http.StatusBadRequest, "Unknown filter; try sync_gateway/bychannel"}
}
channelsParam := h.getQuery("channels")
if channelsParam == "" {
return &base.HTTPError{http.StatusBadRequest, "Missing 'channels' filter parameter"}
}
var err error
userChannels, err = channels.SetFromArray(strings.Split(channelsParam, ","),
channels.ExpandStar)
if err != nil {
return err
}
if len(userChannels) == 0 {
return &base.HTTPError{http.StatusBadRequest, "Empty channel list"}
}
}
switch h.getQuery("feed") {
case "continuous":
return h.handleContinuousChanges(userChannels, options)
case "longpoll":
options.Wait = true
}
return h.handleSimpleChanges(userChannels, options)
}
// Top-level handler for _changes feed requests. Accepts GET or POST requests.
func (h *handler) handleChanges() error {
// http://wiki.apache.org/couchdb/HTTP_database_API#Changes
// http://docs.couchdb.org/en/latest/api/database/changes.html
restExpvars.Add("changesFeeds_total", 1)
restExpvars.Add("changesFeeds_active", 1)
defer restExpvars.Add("changesFeeds_active", -1)
var feed string
var options db.ChangesOptions
var filter string
var channelsArray []string
if h.rq.Method == "GET" {
// GET request has parameters in URL:
feed = h.getQuery("feed")
options.Since = channels.TimedSetFromString(h.getQuery("since"))
options.Limit = int(h.getIntQuery("limit", 0))
options.Conflicts = (h.getQuery("style") == "all_docs")
options.IncludeDocs = (h.getBoolQuery("include_docs"))
filter = h.getQuery("filter")
channelsParam := h.getQuery("channels")
if channelsParam != "" {
channelsArray = strings.Split(channelsParam, ",")
}
} else {
// POST request has parameters in JSON body:
body, err := h.readBody()
if err != nil {
return err
}
feed, options, filter, channelsArray, err = readChangesOptionsFromJSON(body)
if err != nil {
return err
}
}
// Get the channels as parameters to an imaginary "bychannel" filter.
// The default is all channels the user can access.
userChannels := channels.SetOf("*")
if filter != "" {
if filter != "sync_gateway/bychannel" {
return base.HTTPErrorf(http.StatusBadRequest, "Unknown filter; try sync_gateway/bychannel")
}
if channelsArray == nil {
return base.HTTPErrorf(http.StatusBadRequest, "Missing 'channels' filter parameter")
}
var err error
userChannels, err = channels.SetFromArray(channelsArray, channels.ExpandStar)
if err != nil {
return err
}
if len(userChannels) == 0 {
return base.HTTPErrorf(http.StatusBadRequest, "Empty channel list")
}
}
h.db.ChangesClientStats.Increment()
defer h.db.ChangesClientStats.Decrement()
options.Terminator = make(chan bool)
defer close(options.Terminator)
switch feed {
case "normal", "":
return h.sendSimpleChanges(userChannels, options)
case "longpoll":
options.Wait = true
return h.sendSimpleChanges(userChannels, options)
case "continuous":
return h.sendContinuousChangesByHTTP(userChannels, options)
case "websocket":
return h.sendContinuousChangesByWebSocket(userChannels, options)
default:
return base.HTTPErrorf(http.StatusBadRequest, "Unknown feed type")
}
}