chore(fleet): Add "direct" RC option to pull configurations (#30369)

cmd/installer/subcommands/installer/command.go

@@ -293,7 +293,7 @@ func installCommand() *cobra.Command {
 			if err != nil {
 				return err
 			}
-			defer i.stop(err)
+			defer func() { i.stop(err) }()
 			i.span.SetTag("params.url", args[0])
 			return i.Install(i.ctx, args[0], installArgs)
 		},
@@ -313,7 +313,7 @@ func removeCommand() *cobra.Command {
 			if err != nil {
 				return err
 			}
-			defer i.stop(err)
+			defer func() { i.stop(err) }()
 			i.span.SetTag("params.package", args[0])
 			return i.Remove(i.ctx, args[0])
 		},
@@ -332,7 +332,7 @@ func purgeCommand() *cobra.Command {
 			if err != nil {
 				return err
 			}
-			defer i.stop(err)
+			defer func() { i.stop(err) }()
 			i.Purge(i.ctx)
 			return nil
 		},
@@ -351,7 +351,7 @@ func installExperimentCommand() *cobra.Command {
 			if err != nil {
 				return err
 			}
-			defer i.stop(err)
+			defer func() { i.stop(err) }()
 			i.span.SetTag("params.url", args[0])
 			return i.InstallExperiment(i.ctx, args[0])
 		},
@@ -370,7 +370,7 @@ func removeExperimentCommand() *cobra.Command {
 			if err != nil {
 				return err
 			}
-			defer i.stop(err)
+			defer func() { i.stop(err) }()
 			i.span.SetTag("params.package", args[0])
 			return i.RemoveExperiment(i.ctx, args[0])
 		},
@@ -389,7 +389,7 @@ func promoteExperimentCommand() *cobra.Command {
 			if err != nil {
 				return err
 			}
-			defer i.stop(err)
+			defer func() { i.stop(err) }()
 			i.span.SetTag("params.package", args[0])
 			return i.PromoteExperiment(i.ctx, args[0])
 		},
@@ -408,7 +408,7 @@ func installConfigExperimentCommand() *cobra.Command {
 			if err != nil {
 				return err
 			}
-			defer func() { i.Stop(err) }()
+			defer func() { i.stop(err) }()
 			i.span.SetTag("params.package", args[0])
 			i.span.SetTag("params.version", args[1])
 			return i.InstallConfigExperiment(i.ctx, args[0], args[1])
@@ -428,7 +428,7 @@ func removeConfigExperimentCommand() *cobra.Command {
 			if err != nil {
 				return err
 			}
-			defer func() { i.Stop(err) }()
+			defer func() { i.stop(err) }()
 			i.span.SetTag("params.package", args[0])
 			return i.RemoveConfigExperiment(i.ctx, args[0])
 		},
@@ -447,7 +447,7 @@ func promoteConfigExperimentCommand() *cobra.Command {
 			if err != nil {
 				return err
 			}
-			defer func() { i.Stop(err) }()
+			defer func() { i.stop(err) }()
 			i.span.SetTag("params.package", args[0])
 			return i.PromoteConfigExperiment(i.ctx, args[0])
 		},
@@ -466,7 +466,7 @@ func garbageCollectCommand() *cobra.Command {
 			if err != nil {
 				return err
 			}
-			defer i.stop(err)
+			defer func() { i.stop(err) }()
 			return i.GarbageCollect(i.ctx)
 		},
 	}
@@ -489,7 +489,7 @@ func isInstalledCommand() *cobra.Command {
 			if err != nil {
 				return err
 			}
-			defer i.stop(err)
+			defer func() { i.stop(err) }()
 			installed, err := i.IsInstalled(i.ctx, args[0])
 			if err != nil {
 				return err

pkg/config/remote/service/service.go

@@ -17,14 +17,15 @@ import (
 	"errors"
 	"expvar"
 	"fmt"
-	"github.com/DataDog/datadog-agent/pkg/remoteconfig/state"
-	"gopkg.in/DataDog/dd-trace-go.v1/ddtrace/tracer"
 	"net/url"
 	"path"
 	"strconv"
 	"sync"
 	"time"
 
+	"github.com/DataDog/datadog-agent/pkg/remoteconfig/state"
+	"gopkg.in/DataDog/dd-trace-go.v1/ddtrace/tracer"
+
 	"github.com/DataDog/go-tuf/data"
 	tufutil "github.com/DataDog/go-tuf/util"
 	"github.com/benbjohnson/clock"
@@ -247,6 +248,7 @@ type options struct {
 	apiKey                         string
 	traceAgentEnv                  string
 	databaseFileName               string
+	databaseFilePath               string
 	configRootOverride             string
 	directorRootOverride           string
 	clientCacheBypassLimit         int
@@ -261,6 +263,7 @@ var defaultOptions = options{
 	apiKey:                         "",
 	traceAgentEnv:                  "",
 	databaseFileName:               "remote-config.db",
+	databaseFilePath:               "",
 	configRootOverride:             "",
 	directorRootOverride:           "",
 	clientCacheBypassLimit:         defaultCacheBypassLimit,
@@ -283,6 +286,11 @@ func WithDatabaseFileName(fileName string) func(s *options) {
 	return func(s *options) { s.databaseFileName = fileName }
 }
 
+// WithDatabasePath sets the service database path
+func WithDatabasePath(path string) func(s *options) {
+	return func(s *options) { s.databaseFilePath = path }
+}
+
 // WithConfigRootOverride sets the service config root override
 func WithConfigRootOverride(site string, override string) func(s *options) {
 	return func(opts *options) {
@@ -410,7 +418,11 @@ func NewService(cfg model.Reader, rcType, baseRawURL, hostname string, tagsGette
 		return nil, err
 	}
 
-	dbPath := path.Join(cfg.GetString("run_path"), options.databaseFileName)
+	databaseFilePath := cfg.GetString("run_path")
+	if options.databaseFilePath != "" {
+		databaseFilePath = options.databaseFilePath
+	}
+	dbPath := path.Join(databaseFilePath, options.databaseFileName)
 	db, err := openCacheDB(dbPath, agentVersion, authKeys.apiKey)
 	if err != nil {
 		return nil, err

pkg/fleet/daemon/daemon.go

@@ -41,7 +41,7 @@ const (
 	// gcInterval is the interval at which the GC will run
 	gcInterval = 1 * time.Hour
 	// refreshStateInterval is the interval at which the state will be refreshed
-	refreshStateInterval = 1 * time.Minute
+	refreshStateInterval = 30 * time.Second
 )
 
 // Daemon is the fleet daemon in charge of remote install, updates and configuration.
@@ -562,7 +562,7 @@ func (d *daemonImpl) resolveRemoteConfigVersion(ctx context.Context, pkg string)
 	}
 	config, err := d.cdn.Get(ctx, pkg)
 	if err != nil {
-		return "", fmt.Errorf("could not get cdn config: %w", err)
+		return "", err
 	}
 	return config.Version(), nil
 }
@@ -602,9 +602,6 @@ func (d *daemonImpl) refreshState(ctx context.Context) {
 		}
 
 		configVersion, err := d.resolveRemoteConfigVersion(ctx, pkg)
-		if err != nil {
-			log.Errorf("could not get agent remote config version: %v", err)
-		}
 		if err == nil {
 			p.RemoteConfigVersion = configVersion
 		} else if err != cdn.ErrProductNotSupported {

pkg/fleet/env/env.go

@@ -32,6 +32,7 @@ const (
 	envAgentMinorVersion     = "DD_AGENT_MINOR_VERSION"
 	envApmLanguages          = "DD_APM_INSTRUMENTATION_LANGUAGES"
 	envCDNLocalDirPath       = "DD_INSTALLER_DEBUG_CDN_LOCAL_DIR_PATH"
+	envCDNEnabled            = "DD_INSTALLER_CDN_ENABLED"
 )
 
 var defaultEnv = Env{
@@ -88,6 +89,7 @@ type Env struct {
 
 	InstallScript InstallScriptEnv
 
+	CDNEnabled      bool
 	CDNLocalDirPath string
 }
 
@@ -118,6 +120,7 @@ func FromEnv() *Env {
 
 		InstallScript: installScriptEnvFromEnv(),
 
+		CDNEnabled:      strings.ToLower(os.Getenv(envCDNEnabled)) == "true",
 		CDNLocalDirPath: getEnvOrDefault(envCDNLocalDirPath, ""),
 	}
 }

pkg/fleet/internal/cdn/cdn.go

@@ -10,6 +10,7 @@ import (
 	"context"
 	"errors"
 	"regexp"
+	"runtime"
 
 	"github.com/DataDog/datadog-agent/pkg/fleet/env"
 )
@@ -38,10 +39,36 @@ type CDN interface {
 	Close() error
 }
 
-// New creates a new CDN.
+// New creates a new CDN and chooses the implementation depending
+// on the environment
 func New(env *env.Env, configDBPath string) (CDN, error) {
+	if runtime.GOOS == "windows" {
+		// There's an assumption on windows that some directories are already there
+		// but they are in fact created by the regular CDN implementation. Until
+		// there is a fix on windows we keep the previous CDN behaviour for them
+		return newCDNHTTP(env, configDBPath)
+	}
+
+	if !env.RemotePolicies {
+		// Remote policies are not enabled -- we don't need the CDN
+		// and we don't want to create the directories that the CDN
+		// implementation would create. We return a no-op CDN to avoid
+		// nil pointer dereference.
+		return newCDNNoop()
+	}
+
 	if env.CDNLocalDirPath != "" {
-		return newLocal(env)
+		// Mock the CDN for local development or testing
+		return newCDNLocal(env)
 	}
-	return newRemote(env, configDBPath)
+
+	if !env.CDNEnabled {
+		// Remote policies are enabled but we don't want to use the CDN
+		// as it's still in development. We use standard remote config calls
+		// instead (dubbed "direct" CDN).
+		return newCDNRC(env, configDBPath)
+	}
+
+	// Regular CDN with the cloudfront distribution
+	return newCDNHTTP(env, configDBPath)
 }

pkg/fleet/internal/cdn/cdn_remote.go → pkg/fleet/internal/cdn/cdn_http.go

@@ -20,12 +20,12 @@ import (
 	"gopkg.in/DataDog/dd-trace-go.v1/ddtrace/tracer"
 )
 
-type cdnRemote struct {
+type cdnHTTP struct {
 	client              *remoteconfig.HTTPClient
 	currentRootsVersion uint64
 }
 
-func newRemote(env *env.Env, configDBPath string) (CDN, error) {
+func newCDNHTTP(env *env.Env, configDBPath string) (CDN, error) {
 	client, err := remoteconfig.NewHTTPClient(
 		configDBPath,
 		env.Site,
@@ -35,24 +35,24 @@ func newRemote(env *env.Env, configDBPath string) (CDN, error) {
 	if err != nil {
 		return nil, err
 	}
-	return &cdnRemote{
+	return &cdnHTTP{
 		client:              client,
 		currentRootsVersion: 1,
 	}, nil
 }
 
 // Get gets the configuration from the CDN.
-func (c *cdnRemote) Get(ctx context.Context, pkg string) (cfg Config, err error) {
+func (c *cdnHTTP) Get(ctx context.Context, pkg string) (cfg Config, err error) {
 	span, _ := tracer.StartSpanFromContext(ctx, "cdn.Get")
+	span.SetTag("cdn_type", "cdn")
 	defer func() { span.Finish(tracer.WithError(err)) }()
 
-	orderConfig, layers, err := c.get(ctx)
-	if err != nil {
-		return nil, err
-	}
-
 	switch pkg {
 	case "datadog-agent":
+		orderConfig, layers, err := c.get(ctx)
+		if err != nil {
+			return nil, err
+		}
 		cfg, err = newAgentConfig(orderConfig, layers...)
 		if err != nil {
 			return nil, err
@@ -65,12 +65,12 @@ func (c *cdnRemote) Get(ctx context.Context, pkg string) (cfg Config, err error)
 }
 
 // Close cleans up the CDN's resources
-func (c *cdnRemote) Close() error {
+func (c *cdnHTTP) Close() error {
 	return c.client.Close()
 }
 
 // get calls the Remote Config service to get the ordered layers.
-func (c *cdnRemote) get(ctx context.Context) (*orderConfig, [][]byte, error) {
+func (c *cdnHTTP) get(ctx context.Context) (*orderConfig, [][]byte, error) {
 	agentConfigUpdate, err := c.client.GetCDNConfigUpdate(
 		ctx,
 		[]string{"AGENT_CONFIG"},

pkg/fleet/internal/cdn/cdn_local.go

@@ -19,8 +19,8 @@ type cdnLocal struct {
 	dirPath string
 }
 
-// newLocal creates a new local CDN.
-func newLocal(env *env.Env) (CDN, error) {
+// newCDNLocal creates a new local CDN.
+func newCDNLocal(env *env.Env) (CDN, error) {
 	return &cdnLocal{
 		dirPath: env.CDNLocalDirPath,
 	}, nil

pkg/fleet/internal/cdn/cdn_noop.go

@@ -0,0 +1,43 @@
+// Unless explicitly stated otherwise all files in this repository are licensed
+// under the Apache License Version 2.0.
+// This product includes software developed at Datadog (https://www.datadoghq.com/).
+// Copyright 2016-present Datadog, Inc.
+
+package cdn
+
+import (
+	"context"
+
+	"github.com/DataDog/datadog-agent/pkg/util/log"
+)
+
+type cdnNoop struct {
+}
+
+type configNoop struct{}
+
+// newCDNNoop creates a new noop CDN.
+func newCDNNoop() (CDN, error) {
+	return &cdnNoop{}, nil
+}
+
+// Get gets the configuration from the CDN.
+func (c *cdnNoop) Get(_ context.Context, _ string) (Config, error) {
+	log.Debug("Noop CDN get")
+	return &configNoop{}, nil
+}
+
+func (c *cdnNoop) Close() error {
+	log.Debug("Noop CDN close")
+	return nil
+}
+
+func (c *configNoop) Version() string {
+	log.Debug("Noop CDN version")
+	return ""
+}
+
+func (c *configNoop) Write(_ string) error {
+	log.Debug("Noop CDN write")
+	return nil
+}