Files
coder/enterprise/wsproxy/wsproxy.go
2023-04-17 19:57:21 +00:00

251 lines
7.2 KiB
Go

package wsproxy
import (
"context"
"net/http"
"net/url"
"reflect"
"regexp"
"strings"
"time"
"github.com/coder/coder/coderd/httpapi"
"github.com/go-chi/chi/v5"
"github.com/google/uuid"
"github.com/prometheus/client_golang/prometheus"
"go.opentelemetry.io/otel/trace"
"golang.org/x/xerrors"
"cdr.dev/slog"
"github.com/coder/coder/buildinfo"
"github.com/coder/coder/coderd/httpmw"
"github.com/coder/coder/coderd/tracing"
"github.com/coder/coder/coderd/workspaceapps"
"github.com/coder/coder/coderd/wsconncache"
"github.com/coder/coder/codersdk"
"github.com/coder/coder/enterprise/wsproxy/wsproxysdk"
)
type Options struct {
Logger slog.Logger
// DashboardURL is the URL of the primary coderd instance.
DashboardURL *url.URL
// AccessURL is the URL of the WorkspaceProxy. This is the url to communicate
// with this server.
AccessURL *url.URL
// TODO: @emyrk We use these two fields in many places with this comment.
// Maybe we should make some shared options struct?
// AppHostname should be the wildcard hostname to use for workspace
// applications INCLUDING the asterisk, (optional) suffix and leading dot.
// It will use the same scheme and port number as the access URL.
// E.g. "*.apps.coder.com" or "*-apps.coder.com".
AppHostname string
// AppHostnameRegex contains the regex version of options.AppHostname as
// generated by httpapi.CompileHostnamePattern(). It MUST be set if
// options.AppHostname is set.
AppHostnameRegex *regexp.Regexp
RealIPConfig *httpmw.RealIPConfig
// TODO: @emyrk this key needs to be provided via a file or something?
// Maybe we should curl it from the primary over some secure connection?
AppSecurityKey workspaceapps.SecurityKey
Tracing trace.TracerProvider
PrometheusRegistry *prometheus.Registry
APIRateLimit int
SecureAuthCookie bool
DisablePathApps bool
ProxySessionToken string
}
func (o *Options) Validate() error {
var errs optErrors
errs.Required("Logger", o.Logger)
errs.Required("DashboardURL", o.DashboardURL)
errs.Required("AccessURL", o.AccessURL)
errs.Required("RealIPConfig", o.RealIPConfig)
errs.Required("PrometheusRegistry", o.PrometheusRegistry)
errs.NotEmpty("ProxySessionToken", o.ProxySessionToken)
errs.NotEmpty("AppSecurityKey", o.AppSecurityKey)
if len(errs) > 0 {
return errs
}
return nil
}
// Server is an external workspace proxy server. This server can communicate
// directly with a workspace. It requires a primary coderd to establish a said
// connection.
type Server struct {
Options *Options
Handler chi.Router
DashboardURL *url.URL
AppServer *workspaceapps.Server
// Logging/Metrics
Logger slog.Logger
TracerProvider trace.TracerProvider
PrometheusRegistry *prometheus.Registry
// SDKClient is a client to the primary coderd instance authenticated with
// the moon's token.
SDKClient *wsproxysdk.Client
// TODO: Missing:
// - derpserver
// Used for graceful shutdown. Required for the dialer.
ctx context.Context
cancel context.CancelFunc
}
func New(opts *Options) (*Server, error) {
if opts.PrometheusRegistry == nil {
opts.PrometheusRegistry = prometheus.NewRegistry()
}
if err := opts.Validate(); err != nil {
return nil, err
}
// TODO: implement some ping and registration logic
client := wsproxysdk.New(opts.DashboardURL)
err := client.SetSessionToken(opts.ProxySessionToken)
if err != nil {
return nil, xerrors.Errorf("set client token: %w", err)
}
r := chi.NewRouter()
ctx, cancel := context.WithCancel(context.Background())
s := &Server{
Options: opts,
Handler: r,
DashboardURL: opts.DashboardURL,
Logger: opts.Logger.Named("workspace-proxy"),
TracerProvider: opts.Tracing,
PrometheusRegistry: opts.PrometheusRegistry,
SDKClient: client,
ctx: ctx,
cancel: cancel,
}
s.AppServer = &workspaceapps.Server{
Logger: opts.Logger.Named("workspaceapps"),
DashboardURL: opts.DashboardURL,
AccessURL: opts.AccessURL,
Hostname: opts.AppHostname,
HostnameRegex: opts.AppHostnameRegex,
RealIPConfig: opts.RealIPConfig,
SignedTokenProvider: &TokenProvider{
DashboardURL: opts.DashboardURL,
AccessURL: opts.AccessURL,
AppHostname: opts.AppHostname,
Client: client,
SecurityKey: s.Options.AppSecurityKey,
Logger: s.Logger.Named("proxy_token_provider"),
},
WorkspaceConnCache: wsconncache.New(s.DialWorkspaceAgent, 0),
AppSecurityKey: opts.AppSecurityKey,
DisablePathApps: opts.DisablePathApps,
SecureAuthCookie: opts.SecureAuthCookie,
}
// Routes
apiRateLimiter := httpmw.RateLimit(opts.APIRateLimit, time.Minute)
// Persistent middlewares to all routes
r.Use(
// TODO: @emyrk Should we standardize these in some other package?
httpmw.Recover(s.Logger),
tracing.StatusWriterMiddleware,
tracing.Middleware(s.TracerProvider),
httpmw.AttachRequestID,
httpmw.ExtractRealIP(s.Options.RealIPConfig),
httpmw.Logger(s.Logger),
httpmw.Prometheus(s.PrometheusRegistry),
// HandleSubdomain is a middleware that handles all requests to the
// subdomain-based workspace apps.
s.AppServer.HandleSubdomain(apiRateLimiter),
// Build-Version is helpful for debugging.
func(next http.Handler) http.Handler {
return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
w.Header().Add("X-Coder-Build-Version", buildinfo.Version())
next.ServeHTTP(w, r)
})
},
// This header stops a browser from trying to MIME-sniff the content type and
// forces it to stick with the declared content-type. This is the only valid
// value for this header.
// See: https://github.com/coder/security/issues/12
func(next http.Handler) http.Handler {
return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
w.Header().Add("X-Content-Type-Options", "nosniff")
next.ServeHTTP(w, r)
})
},
// TODO: @emyrk we might not need this? But good to have if it does
// not break anything.
httpmw.CSRF(s.Options.SecureAuthCookie),
)
// Attach workspace apps routes.
r.Group(func(r chi.Router) {
r.Use(apiRateLimiter)
s.AppServer.Attach(r)
})
r.Get("/buildinfo", s.buildInfo)
r.Get("/healthz", func(w http.ResponseWriter, r *http.Request) { _, _ = w.Write([]byte("OK")) })
return s, nil
}
func (s *Server) Close() error {
s.cancel()
return s.AppServer.Close()
}
func (s *Server) DialWorkspaceAgent(id uuid.UUID) (*codersdk.WorkspaceAgentConn, error) {
return s.SDKClient.DialWorkspaceAgent(s.ctx, id, nil)
}
func (s *Server) buildInfo(rw http.ResponseWriter, r *http.Request) {
httpapi.Write(r.Context(), rw, http.StatusOK, codersdk.BuildInfoResponse{
ExternalURL: buildinfo.ExternalURL(),
Version: buildinfo.Version(),
DashboardURL: s.DashboardURL.String(),
})
}
type optErrors []error
func (e optErrors) Error() string {
var b strings.Builder
for _, err := range e {
_, _ = b.WriteString(err.Error())
_, _ = b.WriteString("\n")
}
return b.String()
}
func (e *optErrors) Required(name string, v any) {
if v == nil {
*e = append(*e, xerrors.Errorf("%s is required, got <nil>", name))
}
}
func (e *optErrors) NotEmpty(name string, v any) {
if reflect.ValueOf(v).IsZero() {
*e = append(*e, xerrors.Errorf("%s is required, got the zero value", name))
}
}