Get to middleware

coder · ammario · May 24, 2023 · May 15, 2023 · May 16, 2023 · May 16, 2023
commit 0b2d56b0fa658f696b0b30f169519842fc0dd737
diff --git a/cli/root.go b/cli/root.go
@@ -431,7 +431,7 @@ type RootCmd struct {
 func telemetryInvocation(i *clibase.Invocation) telemetry.CLIInvocation {
 	var topts []telemetry.CLIOption
 	for _, opt := range i.Command.FullOptions() {
-		if opt.Value.String() == opt.Default {
+		if opt.ValueSource == clibase.ValueSourceNone || opt.ValueSource == clibase.ValueSourceDefault {
 			continue
 		}
 		topts = append(topts, telemetry.CLIOption{
@@ -493,7 +493,7 @@ func (r *RootCmd) InitClient(client *codersdk.Client) clibase.MiddlewareFunc {
 			}
 			err = r.setClient(
 				client, r.clientURL,
-				append(r.header, "Coder-CLI-Invokation="+
+				append(r.header, codersdk.CLITelemetryHeader+"="+
 					base64.StdEncoding.EncodeToString(byt),
 				),
 			)

diff --git a/coderd/httpmw/telemetry.go b/coderd/httpmw/telemetry.go
@@ -0,0 +1,78 @@
+package httpmw
+
+import (
+	"encoding/base64"
+	"encoding/json"
+	"net/http"
+	"sync"
+	"time"
+
+	"tailscale.com/tstime/rate"
+
+	"cdr.dev/slog"
+	"github.com/coder/coder/coderd/telemetry"
+	"github.com/coder/coder/codersdk"
+)
+
+func ReportCLITelemetry(log slog.Logger, rep telemetry.Reporter) func(http.Handler) http.Handler {
+	var mu sync.Mutex
+
+	var (
+		// We send telemetry at most once per minute.
+		limiter = rate.NewLimiter(rate.Every(time.Minute), 1)
+		queue   []telemetry.CLIInvocation
+	)
+
+	return func(next http.Handler) http.Handler {
+		return http.HandlerFunc(func(rw http.ResponseWriter, r *http.Request) {
+			defer next.ServeHTTP(rw, r)
+			payload := r.Header.Get(codersdk.CLITelemetryHeader)
+
+			// We do simple checks and processing outside of the goroutine
+			// to avoid the overhead of an additional goroutine on every
+			// request.
+			if payload == "" {
+				return
+			}
+
+			byt, err := base64.StdEncoding.DecodeString(payload)
+			if err != nil {
+				log.Error(
+					r.Context(),
+					"base64 decode CLI telemetry header",
+					slog.F("error", err),
+				)
+				return
+			}
+
+			var inv telemetry.CLIInvocation
+			err = json.Unmarshal(byt, &inv)
+			if err != nil {
+				log.Error(
+					r.Context(),
+					"unmarshal CLI telemetry header",
+					slog.Error(err),
+				)
+				return
+			}
+
+			go func() {
+				mu.Lock()
+				defer mu.Unlock()
+
+				queue = append(queue, inv)
+				if !limiter.Allow() && len(queue) < 1024 {
+					return
+				}
+				rep.Report(&telemetry.Snapshot{
+					CLIInvocations: queue,
+				})
+				log.Debug(
+					r.Context(),
+					"reported CLI telemetry", slog.F("count", len(queue)),
+				)
+				queue = queue[:0]
+			}()
+		})
+	}
+}
diff --git a/coderd/telemetry/telemetry.go b/coderd/telemetry/telemetry.go
@@ -700,7 +700,7 @@ type Snapshot struct {
 	WorkspaceBuilds           []WorkspaceBuild            `json:"workspace_build"`
 	WorkspaceResources        []WorkspaceResource         `json:"workspace_resources"`
 	WorkspaceResourceMetadata []WorkspaceResourceMetadata `json:"workspace_resource_metadata"`
-	CLIInvokations            []CLIInvocation             `json:"cli_invocations"`
+	CLIInvocations            []CLIInvocation             `json:"cli_invocations"`
 }
 
 // Deployment contains information about the host running Coder.
@@ -881,8 +881,8 @@ type CLIOption struct {
 }
 
 type CLIInvocation struct {
-	Command string `json:"command"`
-	Options []CLIOption
+	Command string      `json:"command"`
+	Options []CLIOption `json:"options"`
 }
 
 type noopReporter struct{}

diff --git a/codersdk/client.go b/codersdk/client.go
@@ -61,6 +61,16 @@ const (
 	// Only owners can bypass rate limits. This is typically used for scale testing.
 	// nolint: gosec
 	BypassRatelimitHeader = "X-Coder-Bypass-Ratelimit"
+
+	// Note: the use of X- prefix is deprecated, and we should eventually remove
+	// it from BypassRatelimitHeader.
+	//
+	// See: https://datatracker.ietf.org/doc/html/rfc6648.
+
+	// CLIInvokableHeader contains a base64-encoded representation of the CLI
+	// command that was invoked to produce the request. It is for internal use
+	// only and should not be relied upon.
+	CLITelemetryHeader = "Coder-CLI-Telemetry"
 )
 
 // loggableMimeTypes is a list of MIME types that are safe to log