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workspaceagents.go
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workspaceagents.go
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package coderd
import (
"context"
"database/sql"
"encoding/json"
"fmt"
"io"
"net"
"net/http"
"strconv"
"time"
"github.com/google/uuid"
"github.com/hashicorp/yamux"
"golang.org/x/xerrors"
"nhooyr.io/websocket"
"cdr.dev/slog"
"github.com/coder/coder/agent"
"github.com/coder/coder/coderd/database"
"github.com/coder/coder/coderd/httpapi"
"github.com/coder/coder/coderd/httpmw"
"github.com/coder/coder/coderd/rbac"
"github.com/coder/coder/coderd/turnconn"
"github.com/coder/coder/codersdk"
"github.com/coder/coder/peer"
"github.com/coder/coder/peerbroker"
"github.com/coder/coder/peerbroker/proto"
"github.com/coder/coder/provisionersdk"
)
func (api *API) workspaceAgent(rw http.ResponseWriter, r *http.Request) {
workspaceAgent := httpmw.WorkspaceAgentParam(r)
workspace := httpmw.WorkspaceParam(r)
if !api.Authorize(r, rbac.ActionRead, workspace) {
httpapi.ResourceNotFound(rw)
return
}
dbApps, err := api.Database.GetWorkspaceAppsByAgentID(r.Context(), workspaceAgent.ID)
if err != nil && !xerrors.Is(err, sql.ErrNoRows) {
httpapi.Write(rw, http.StatusInternalServerError, httpapi.Response{
Message: "Internal error fetching workspace agent applications.",
Detail: err.Error(),
})
return
}
apiAgent, err := convertWorkspaceAgent(workspaceAgent, convertApps(dbApps), api.AgentConnectionUpdateFrequency)
if err != nil {
httpapi.Write(rw, http.StatusInternalServerError, httpapi.Response{
Message: "Internal error reading workspace agent.",
Detail: err.Error(),
})
return
}
httpapi.Write(rw, http.StatusOK, apiAgent)
}
func (api *API) workspaceAgentDial(rw http.ResponseWriter, r *http.Request) {
api.websocketWaitMutex.Lock()
api.websocketWaitGroup.Add(1)
api.websocketWaitMutex.Unlock()
defer api.websocketWaitGroup.Done()
workspaceAgent := httpmw.WorkspaceAgentParam(r)
workspace := httpmw.WorkspaceParam(r)
if !api.Authorize(r, rbac.ActionUpdate, workspace) {
httpapi.ResourceNotFound(rw)
return
}
apiAgent, err := convertWorkspaceAgent(workspaceAgent, nil, api.AgentConnectionUpdateFrequency)
if err != nil {
httpapi.Write(rw, http.StatusInternalServerError, httpapi.Response{
Message: "Internal error reading workspace agent.",
Detail: err.Error(),
})
return
}
if apiAgent.Status != codersdk.WorkspaceAgentConnected {
httpapi.Write(rw, http.StatusPreconditionFailed, httpapi.Response{
Message: fmt.Sprintf("Agent isn't connected! Status: %s.", apiAgent.Status),
})
return
}
conn, err := websocket.Accept(rw, r, nil)
if err != nil {
httpapi.Write(rw, http.StatusBadRequest, httpapi.Response{
Message: "Failed to accept websocket.",
Detail: err.Error(),
})
return
}
ctx, wsNetConn := websocketNetConn(r.Context(), conn, websocket.MessageBinary)
defer wsNetConn.Close() // Also closes conn.
config := yamux.DefaultConfig()
config.LogOutput = io.Discard
session, err := yamux.Server(wsNetConn, config)
if err != nil {
_ = conn.Close(websocket.StatusAbnormalClosure, err.Error())
return
}
err = peerbroker.ProxyListen(ctx, session, peerbroker.ProxyOptions{
ChannelID: workspaceAgent.ID.String(),
Logger: api.Logger.Named("peerbroker-proxy-dial"),
Pubsub: api.Pubsub,
})
if err != nil {
_ = conn.Close(websocket.StatusInternalError, httpapi.WebsocketCloseSprintf("serve: %s", err))
return
}
}
func (api *API) workspaceAgentMetadata(rw http.ResponseWriter, r *http.Request) {
workspaceAgent := httpmw.WorkspaceAgent(r)
apiAgent, err := convertWorkspaceAgent(workspaceAgent, nil, api.AgentConnectionUpdateFrequency)
if err != nil {
httpapi.Write(rw, http.StatusInternalServerError, httpapi.Response{
Message: "Internal error reading workspace agent.",
Detail: err.Error(),
})
return
}
resource, err := api.Database.GetWorkspaceResourceByID(r.Context(), workspaceAgent.ResourceID)
if err != nil {
httpapi.Write(rw, http.StatusInternalServerError, httpapi.Response{
Message: "Internal error fetching workspace resources.",
Detail: err.Error(),
})
return
}
build, err := api.Database.GetWorkspaceBuildByJobID(r.Context(), resource.JobID)
if err != nil {
httpapi.Write(rw, http.StatusInternalServerError, httpapi.Response{
Message: "Internal error fetching workspace build.",
Detail: err.Error(),
})
return
}
workspace, err := api.Database.GetWorkspaceByID(r.Context(), build.WorkspaceID)
if err != nil {
httpapi.Write(rw, http.StatusInternalServerError, httpapi.Response{
Message: "Internal error fetching workspace.",
Detail: err.Error(),
})
return
}
owner, err := api.Database.GetUserByID(r.Context(), workspace.OwnerID)
if err != nil {
httpapi.Write(rw, http.StatusInternalServerError, httpapi.Response{
Message: "Internal error fetching workspace owner.",
Detail: err.Error(),
})
return
}
httpapi.Write(rw, http.StatusOK, agent.Metadata{
OwnerEmail: owner.Email,
OwnerUsername: owner.Username,
EnvironmentVariables: apiAgent.EnvironmentVariables,
StartupScript: apiAgent.StartupScript,
Directory: apiAgent.Directory,
})
}
func (api *API) workspaceAgentListen(rw http.ResponseWriter, r *http.Request) {
api.websocketWaitMutex.Lock()
api.websocketWaitGroup.Add(1)
api.websocketWaitMutex.Unlock()
defer api.websocketWaitGroup.Done()
workspaceAgent := httpmw.WorkspaceAgent(r)
resource, err := api.Database.GetWorkspaceResourceByID(r.Context(), workspaceAgent.ResourceID)
if err != nil {
httpapi.Write(rw, http.StatusBadRequest, httpapi.Response{
Message: "Failed to accept websocket.",
Detail: err.Error(),
})
return
}
build, err := api.Database.GetWorkspaceBuildByJobID(r.Context(), resource.JobID)
if err != nil {
httpapi.Write(rw, http.StatusBadRequest, httpapi.Response{
Message: "Internal error fetching workspace build job.",
Detail: err.Error(),
})
return
}
// Ensure the resource is still valid!
// We only accept agents for resources on the latest build.
ensureLatestBuild := func() error {
latestBuild, err := api.Database.GetLatestWorkspaceBuildByWorkspaceID(r.Context(), build.WorkspaceID)
if err != nil {
return err
}
if build.ID != latestBuild.ID {
return xerrors.New("build is outdated")
}
return nil
}
err = ensureLatestBuild()
if err != nil {
api.Logger.Debug(r.Context(), "agent tried to connect from non-latest built",
slog.F("resource", resource),
slog.F("agent", workspaceAgent),
)
httpapi.Write(rw, http.StatusForbidden, httpapi.Response{
Message: "Agent trying to connect from non-latest build.",
Detail: err.Error(),
})
return
}
conn, err := websocket.Accept(rw, r, &websocket.AcceptOptions{
CompressionMode: websocket.CompressionDisabled,
})
if err != nil {
httpapi.Write(rw, http.StatusBadRequest, httpapi.Response{
Message: "Failed to accept websocket.",
Detail: err.Error(),
})
return
}
ctx, wsNetConn := websocketNetConn(r.Context(), conn, websocket.MessageBinary)
defer wsNetConn.Close() // Also closes conn.
config := yamux.DefaultConfig()
config.LogOutput = io.Discard
session, err := yamux.Server(wsNetConn, config)
if err != nil {
_ = conn.Close(websocket.StatusAbnormalClosure, err.Error())
return
}
closer, err := peerbroker.ProxyDial(proto.NewDRPCPeerBrokerClient(provisionersdk.Conn(session)), peerbroker.ProxyOptions{
ChannelID: workspaceAgent.ID.String(),
Pubsub: api.Pubsub,
Logger: api.Logger.Named("peerbroker-proxy-listen"),
})
if err != nil {
_ = conn.Close(websocket.StatusAbnormalClosure, err.Error())
return
}
defer closer.Close()
firstConnectedAt := workspaceAgent.FirstConnectedAt
if !firstConnectedAt.Valid {
firstConnectedAt = sql.NullTime{
Time: database.Now(),
Valid: true,
}
}
lastConnectedAt := sql.NullTime{
Time: database.Now(),
Valid: true,
}
disconnectedAt := workspaceAgent.DisconnectedAt
updateConnectionTimes := func() error {
err = api.Database.UpdateWorkspaceAgentConnectionByID(ctx, database.UpdateWorkspaceAgentConnectionByIDParams{
ID: workspaceAgent.ID,
FirstConnectedAt: firstConnectedAt,
LastConnectedAt: lastConnectedAt,
DisconnectedAt: disconnectedAt,
})
if err != nil {
return err
}
return nil
}
defer func() {
disconnectedAt = sql.NullTime{
Time: database.Now(),
Valid: true,
}
_ = updateConnectionTimes()
}()
err = updateConnectionTimes()
if err != nil {
_ = conn.Close(websocket.StatusAbnormalClosure, err.Error())
return
}
api.Logger.Info(ctx, "accepting agent", slog.F("resource", resource), slog.F("agent", workspaceAgent))
ticker := time.NewTicker(api.AgentConnectionUpdateFrequency)
defer ticker.Stop()
for {
select {
case <-session.CloseChan():
return
case <-ticker.C:
lastConnectedAt = sql.NullTime{
Time: database.Now(),
Valid: true,
}
err = updateConnectionTimes()
if err != nil {
_ = conn.Close(websocket.StatusAbnormalClosure, err.Error())
return
}
err = ensureLatestBuild()
if err != nil {
// Disconnect agents that are no longer valid.
_ = conn.Close(websocket.StatusGoingAway, "")
return
}
}
}
}
func (api *API) workspaceAgentICEServers(rw http.ResponseWriter, _ *http.Request) {
httpapi.Write(rw, http.StatusOK, api.ICEServers)
}
// workspaceAgentTurn proxies a WebSocket connection to the TURN server.
func (api *API) workspaceAgentTurn(rw http.ResponseWriter, r *http.Request) {
api.websocketWaitMutex.Lock()
api.websocketWaitGroup.Add(1)
api.websocketWaitMutex.Unlock()
defer api.websocketWaitGroup.Done()
localAddress, _ := r.Context().Value(http.LocalAddrContextKey).(*net.TCPAddr)
remoteAddress := &net.TCPAddr{
IP: net.ParseIP(r.RemoteAddr),
}
// By default requests have the remote address and port.
host, port, err := net.SplitHostPort(r.RemoteAddr)
if err != nil {
httpapi.Write(rw, http.StatusBadRequest, httpapi.Response{
Message: "Invalid remote address.",
Detail: err.Error(),
})
return
}
remoteAddress.IP = net.ParseIP(host)
remoteAddress.Port, err = strconv.Atoi(port)
if err != nil {
httpapi.Write(rw, http.StatusBadRequest, httpapi.Response{
Message: fmt.Sprintf("Port for remote address %q must be an integer.", r.RemoteAddr),
Detail: err.Error(),
})
return
}
wsConn, err := websocket.Accept(rw, r, &websocket.AcceptOptions{
CompressionMode: websocket.CompressionDisabled,
})
if err != nil {
httpapi.Write(rw, http.StatusBadRequest, httpapi.Response{
Message: "Failed to accept websocket.",
Detail: err.Error(),
})
return
}
ctx, wsNetConn := websocketNetConn(r.Context(), wsConn, websocket.MessageBinary)
defer wsNetConn.Close() // Also closes conn.
api.Logger.Debug(ctx, "accepting turn connection", slog.F("remote-address", r.RemoteAddr), slog.F("local-address", localAddress))
select {
case <-api.TURNServer.Accept(wsNetConn, remoteAddress, localAddress).Closed():
case <-ctx.Done():
}
api.Logger.Debug(ctx, "completed turn connection", slog.F("remote-address", r.RemoteAddr), slog.F("local-address", localAddress))
}
// workspaceAgentPTY spawns a PTY and pipes it over a WebSocket.
// This is used for the web terminal.
func (api *API) workspaceAgentPTY(rw http.ResponseWriter, r *http.Request) {
api.websocketWaitMutex.Lock()
api.websocketWaitGroup.Add(1)
api.websocketWaitMutex.Unlock()
defer api.websocketWaitGroup.Done()
workspaceAgent := httpmw.WorkspaceAgentParam(r)
workspace := httpmw.WorkspaceParam(r)
if !api.Authorize(r, rbac.ActionUpdate, workspace) {
httpapi.ResourceNotFound(rw)
return
}
apiAgent, err := convertWorkspaceAgent(workspaceAgent, nil, api.AgentConnectionUpdateFrequency)
if err != nil {
httpapi.Write(rw, http.StatusInternalServerError, httpapi.Response{
Message: "Internal error reading workspace agent.",
Detail: err.Error(),
})
return
}
if apiAgent.Status != codersdk.WorkspaceAgentConnected {
httpapi.Write(rw, http.StatusPreconditionRequired, httpapi.Response{
Message: fmt.Sprintf("Agent state is %q, it must be in the %q state.", apiAgent.Status, codersdk.WorkspaceAgentConnected),
})
return
}
reconnect, err := uuid.Parse(r.URL.Query().Get("reconnect"))
if err != nil {
httpapi.Write(rw, http.StatusBadRequest, httpapi.Response{
Message: "Query param 'reconnect' must be a valid UUID.",
Validations: []httpapi.Error{
{Field: "reconnect", Detail: "invalid UUID"},
},
})
return
}
height, err := strconv.Atoi(r.URL.Query().Get("height"))
if err != nil {
height = 80
}
width, err := strconv.Atoi(r.URL.Query().Get("width"))
if err != nil {
width = 80
}
conn, err := websocket.Accept(rw, r, &websocket.AcceptOptions{
CompressionMode: websocket.CompressionDisabled,
})
if err != nil {
httpapi.Write(rw, http.StatusBadRequest, httpapi.Response{
Message: "Failed to accept websocket.",
Detail: err.Error(),
})
return
}
_, wsNetConn := websocketNetConn(r.Context(), conn, websocket.MessageBinary)
defer wsNetConn.Close() // Also closes conn.
agentConn, release, err := api.workspaceAgentCache.Acquire(r, workspaceAgent.ID)
if err != nil {
_ = conn.Close(websocket.StatusInternalError, httpapi.WebsocketCloseSprintf("dial workspace agent: %s", err))
return
}
defer release()
ptNetConn, err := agentConn.ReconnectingPTY(reconnect.String(), uint16(height), uint16(width), r.URL.Query().Get("command"))
if err != nil {
_ = conn.Close(websocket.StatusInternalError, httpapi.WebsocketCloseSprintf("dial: %s", err))
return
}
defer ptNetConn.Close()
// Pipe the ends together!
go func() {
_, _ = io.Copy(wsNetConn, ptNetConn)
}()
_, _ = io.Copy(ptNetConn, wsNetConn)
}
// dialWorkspaceAgent connects to a workspace agent by ID. Only rely on
// r.Context() for cancellation if it's use is safe or r.Hijack() has
// not been performed.
func (api *API) dialWorkspaceAgent(r *http.Request, agentID uuid.UUID) (*agent.Conn, error) {
client, server := provisionersdk.TransportPipe()
ctx, cancelFunc := context.WithCancel(context.Background())
go func() {
_ = peerbroker.ProxyListen(ctx, server, peerbroker.ProxyOptions{
ChannelID: agentID.String(),
Logger: api.Logger.Named("peerbroker-proxy-dial"),
Pubsub: api.Pubsub,
})
_ = client.Close()
_ = server.Close()
}()
peerClient := proto.NewDRPCPeerBrokerClient(provisionersdk.Conn(client))
stream, err := peerClient.NegotiateConnection(ctx)
if err != nil {
cancelFunc()
return nil, xerrors.Errorf("negotiate: %w", err)
}
options := &peer.ConnOptions{
Logger: api.Logger.Named("agent-dialer"),
}
options.SettingEngine.SetSrflxAcceptanceMinWait(0)
options.SettingEngine.SetRelayAcceptanceMinWait(0)
// Use the ProxyDialer for the TURN server.
// This is required for connections where P2P is not enabled.
options.SettingEngine.SetICEProxyDialer(turnconn.ProxyDialer(func() (c net.Conn, err error) {
clientPipe, serverPipe := net.Pipe()
go func() {
<-ctx.Done()
_ = clientPipe.Close()
_ = serverPipe.Close()
}()
localAddress, _ := r.Context().Value(http.LocalAddrContextKey).(*net.TCPAddr)
remoteAddress := &net.TCPAddr{
IP: net.ParseIP(r.RemoteAddr),
}
// By default requests have the remote address and port.
host, port, err := net.SplitHostPort(r.RemoteAddr)
if err != nil {
return nil, xerrors.Errorf("split remote address: %w", err)
}
remoteAddress.IP = net.ParseIP(host)
remoteAddress.Port, err = strconv.Atoi(port)
if err != nil {
return nil, xerrors.Errorf("convert remote port: %w", err)
}
api.TURNServer.Accept(clientPipe, remoteAddress, localAddress)
return serverPipe, nil
}))
peerConn, err := peerbroker.Dial(stream, append(api.ICEServers, turnconn.Proxy), options)
if err != nil {
cancelFunc()
return nil, xerrors.Errorf("dial: %w", err)
}
go func() {
<-peerConn.Closed()
cancelFunc()
}()
return &agent.Conn{
Negotiator: peerClient,
Conn: peerConn,
}, nil
}
func convertApps(dbApps []database.WorkspaceApp) []codersdk.WorkspaceApp {
apps := make([]codersdk.WorkspaceApp, 0)
for _, dbApp := range dbApps {
apps = append(apps, codersdk.WorkspaceApp{
ID: dbApp.ID,
Name: dbApp.Name,
Command: dbApp.Command.String,
Icon: dbApp.Icon,
})
}
return apps
}
func convertWorkspaceAgent(dbAgent database.WorkspaceAgent, apps []codersdk.WorkspaceApp, agentUpdateFrequency time.Duration) (codersdk.WorkspaceAgent, error) {
var envs map[string]string
if dbAgent.EnvironmentVariables.Valid {
err := json.Unmarshal(dbAgent.EnvironmentVariables.RawMessage, &envs)
if err != nil {
return codersdk.WorkspaceAgent{}, xerrors.Errorf("unmarshal: %w", err)
}
}
workspaceAgent := codersdk.WorkspaceAgent{
ID: dbAgent.ID,
CreatedAt: dbAgent.CreatedAt,
UpdatedAt: dbAgent.UpdatedAt,
ResourceID: dbAgent.ResourceID,
InstanceID: dbAgent.AuthInstanceID.String,
Name: dbAgent.Name,
Architecture: dbAgent.Architecture,
OperatingSystem: dbAgent.OperatingSystem,
StartupScript: dbAgent.StartupScript.String,
EnvironmentVariables: envs,
Directory: dbAgent.Directory,
Apps: apps,
}
if dbAgent.FirstConnectedAt.Valid {
workspaceAgent.FirstConnectedAt = &dbAgent.FirstConnectedAt.Time
}
if dbAgent.LastConnectedAt.Valid {
workspaceAgent.LastConnectedAt = &dbAgent.LastConnectedAt.Time
}
if dbAgent.DisconnectedAt.Valid {
workspaceAgent.DisconnectedAt = &dbAgent.DisconnectedAt.Time
}
switch {
case !dbAgent.FirstConnectedAt.Valid:
// If the agent never connected, it's waiting for the compute
// to start up.
workspaceAgent.Status = codersdk.WorkspaceAgentConnecting
case dbAgent.DisconnectedAt.Time.After(dbAgent.LastConnectedAt.Time):
// If we've disconnected after our last connection, we know the
// agent is no longer connected.
workspaceAgent.Status = codersdk.WorkspaceAgentDisconnected
case agentUpdateFrequency*2 >= database.Now().Sub(dbAgent.LastConnectedAt.Time):
// The connection updated it's timestamp within the update frequency.
// We multiply by two to allow for some lag.
workspaceAgent.Status = codersdk.WorkspaceAgentConnected
case database.Now().Sub(dbAgent.LastConnectedAt.Time) > agentUpdateFrequency*2:
// The connection died without updating the last connected.
workspaceAgent.Status = codersdk.WorkspaceAgentDisconnected
}
return workspaceAgent, nil
}
// wsNetConn wraps net.Conn created by websocket.NetConn(). Cancel func
// is called if a read or write error is encountered.
type wsNetConn struct {
cancel context.CancelFunc
net.Conn
}
func (c *wsNetConn) Read(b []byte) (n int, err error) {
n, err = c.Conn.Read(b)
if err != nil {
c.cancel()
}
return n, err
}
func (c *wsNetConn) Write(b []byte) (n int, err error) {
n, err = c.Conn.Write(b)
if err != nil {
c.cancel()
}
return n, err
}
func (c *wsNetConn) Close() error {
defer c.cancel()
return c.Conn.Close()
}
// websocketNetConn wraps websocket.NetConn and returns a context that
// is tied to the parent context and the lifetime of the conn. Any error
// during read or write will cancel the context, but not close the
// conn. Close should be called to release context resources.
func websocketNetConn(ctx context.Context, conn *websocket.Conn, msgType websocket.MessageType) (context.Context, net.Conn) {
ctx, cancel := context.WithCancel(ctx)
nc := websocket.NetConn(ctx, conn, msgType)
return ctx, &wsNetConn{
cancel: cancel,
Conn: nc,
}
}