bigbluebutton-Github/bbb-graphql-middleware/internal/hasura/client.go

116 lines
3.7 KiB
Go

package hasura
import (
"bbb-graphql-middleware/config"
"bbb-graphql-middleware/internal/hasura/conn/reader"
"bbb-graphql-middleware/internal/hasura/conn/writer"
"context"
"fmt"
"math"
"net/http"
"net/http/cookiejar"
"net/url"
"sync"
"bbb-graphql-middleware/internal/common"
"golang.org/x/xerrors"
"nhooyr.io/websocket"
)
var lastHasuraConnectionId int
var hasuraEndpoint = config.GetConfig().Hasura.Url
// Hasura client connection
func HasuraClient(
browserConnection *common.BrowserConnection) error {
// Obtain id for this connection
lastHasuraConnectionId++
hasuraConnectionId := "HC" + fmt.Sprintf("%010d", lastHasuraConnectionId)
browserConnection.Logger = browserConnection.Logger.WithField("hasuraConnectionId", hasuraConnectionId)
defer browserConnection.Logger.Debugf("finished")
// Add sub-protocol
var dialOptions websocket.DialOptions
dialOptions.Subprotocols = append(dialOptions.Subprotocols, "graphql-transport-ws")
// Create cookie jar
jar, err := cookiejar.New(nil)
if err != nil {
return xerrors.Errorf("failed to create cookie jar: %w", err)
}
parsedURL, err := url.Parse(hasuraEndpoint)
if err != nil {
return xerrors.Errorf("failed to parse url: %w", err)
}
parsedURL.Scheme = "http"
jar.SetCookies(parsedURL, browserConnection.BrowserRequestCookies)
hc := &http.Client{
Jar: jar,
}
dialOptions.HTTPClient = hc
// Create a context for the hasura connection, that depends on the browser context
// this means that if browser connection is closed, the hasura connection will close also
// this also means that we can close the hasura connection without closing the browser one
// this is used for the invalidation process (reconnection only on the hasura side )
var hasuraConnectionContext, hasuraConnectionContextCancel = context.WithCancel(browserConnection.Context)
defer hasuraConnectionContextCancel()
var thisConnection = common.HasuraConnection{
Id: hasuraConnectionId,
BrowserConn: browserConnection,
Context: hasuraConnectionContext,
ContextCancelFunc: hasuraConnectionContextCancel,
}
browserConnection.HasuraConnection = &thisConnection
defer func() {
//When Hasura sends an CloseError, it will forward the error to the browser and close the connection
if thisConnection.WebsocketCloseError != nil {
browserConnection.Logger.Infof("Closing browser connection because Hasura connection was closed, reason: %s", thisConnection.WebsocketCloseError.Reason)
browserConnection.Websocket.Close(thisConnection.WebsocketCloseError.Code, thisConnection.WebsocketCloseError.Reason)
browserConnection.ContextCancelFunc()
}
browserConnection.HasuraConnection = nil
//It's necessary to freeze the channel to avoid client trying to start subscriptions before Hasura connection is initialised
//It will unfreeze after `connection_ack` is sent by Hasura
browserConnection.FromBrowserToHasuraChannel.FreezeChannel()
}()
// Make the connection
hasuraWsConn, _, err := websocket.Dial(hasuraConnectionContext, hasuraEndpoint, &dialOptions)
if err != nil {
return xerrors.Errorf("error connecting to hasura: %v", err)
}
defer hasuraWsConn.Close(websocket.StatusInternalError, "the sky is falling")
hasuraWsConn.SetReadLimit(math.MaxInt64 - 1)
thisConnection.Websocket = hasuraWsConn
// Log the connection success
browserConnection.Logger.Info("connected with Hasura")
// Configure the wait group
var wg sync.WaitGroup
wg.Add(2)
// Start routines
// reads from browser, writes to hasura
go writer.HasuraConnectionWriter(&thisConnection, &wg, browserConnection.ConnectionInitMessage)
// reads from hasura, writes to browser
go reader.HasuraConnectionReader(&thisConnection, &wg)
// Wait
wg.Wait()
return nil
}