Implement requires field for checking if required plugins are loaded or not

cmd/config_parser.go

@@ -36,9 +36,9 @@ func getPath(path string) string {
 // 	return nil
 // }
 
-// verificationPolicy returns the verification policy for the plugin from config file.
+// verificationPolicy returns the hook verification policy from plugin config file.
 func verificationPolicy() plugin.Policy {
-	vPolicy := globalConfig.String("plugins.verificationPolicy")
+	vPolicy := pluginConfig.String("plugins.verificationPolicy")
 	verificationPolicy := plugin.PassDown // default
 	switch vPolicy {
 	case "ignore":
@@ -52,6 +52,20 @@ func verificationPolicy() plugin.Policy {
 	return verificationPolicy
 }
 
+// pluginCompatPolicy returns the plugin compatibility policy from plugin config file.
+func pluginCompatPolicy() plugin.CompatPolicy {
+	vPolicy := pluginConfig.String("plugins.compatibilityPolicy")
+	compatPolicy := plugin.Strict // default
+	switch vPolicy {
+	case "strict":
+		compatPolicy = plugin.Strict
+	case "loose":
+		compatPolicy = plugin.Loose
+	}
+
+	return compatPolicy
+}
+
 // loggerConfig returns the logger config from config file.
 func loggerConfig() logging.LoggerConfig {
 	cfg := logging.LoggerConfig{StartupMsg: true}

cmd/run.go

@@ -57,7 +57,10 @@ var runCmd = &cobra.Command{
 			}
 		}
 
-		// Load plugins and register their hooks
+		// Set the plugin compatibility policy.
+		pluginRegistry.CompatPolicy = pluginCompatPolicy()
+
+		// Load plugins and register their hooks.
 		pluginRegistry.LoadPlugins(pluginConfig)
 
 		if f, err := cmd.Flags().GetString("config"); err == nil {
@@ -68,7 +71,7 @@ var runCmd = &cobra.Command{
 			}
 		}
 
-		// Get hooks signature verification policy
+		// Get hooks signature verification policy.
 		hooksConfig.Verification = verificationPolicy()
 
 		// The config will be passed to the hooks, and in turn to the plugins that
@@ -91,11 +94,11 @@ var runCmd = &cobra.Command{
 			}
 		}
 
-		// Create a new logger from the config
+		// Create a new logger from the config.
 		loggerCfg := loggerConfig()
 		logger := logging.NewLogger(loggerCfg)
 
-		// Replace the default logger with the new one from the config
+		// Replace the default logger with the new one from the config.
 		hooksConfig.Logger = logger
 
 		// This is a notification hook, so we don't care about the result.
@@ -111,7 +114,7 @@ var runCmd = &cobra.Command{
 			logger.Error().Err(err).Msg("Failed to run OnNewLogger hooks")
 		}
 
-		// Create and initialize a pool of connections
+		// Create and initialize a pool of connections.
 		poolSize, clientConfig := poolConfig()
 		pool := pool.NewPool(poolSize)
 
@@ -136,10 +139,10 @@ var runCmd = &cobra.Command{
 					"address":            clientConfig.Address,
 					"receiveBufferSize":  clientConfig.ReceiveBufferSize,
 					"receiveChunkSize":   clientConfig.ReceiveChunkSize,
-					"receiveDeadline":    clientConfig.ReceiveDeadline,
-					"sendDeadline":       clientConfig.SendDeadline,
+					"receiveDeadline":    clientConfig.ReceiveDeadline.Seconds(),
+					"sendDeadline":       clientConfig.SendDeadline.Seconds(),
 					"tcpKeepAlive":       clientConfig.TCPKeepAlive,
-					"tcpKeepAlivePeriod": clientConfig.TCPKeepAlivePeriod,
+					"tcpKeepAlivePeriod": clientConfig.TCPKeepAlivePeriod.Seconds(),
 				}
 				_, err := hooksConfig.Run(
 					context.Background(),
@@ -178,7 +181,7 @@ var runCmd = &cobra.Command{
 			logger.Error().Err(err).Msg("Failed to run OnNewPool hooks")
 		}
 
-		// Create a prefork proxy with the pool of clients
+		// Create a prefork proxy with the pool of clients.
 		elastic, reuseElasticClients, elasticClientConfig := proxyConfig()
 		proxy := network.NewProxy(
 			pool, hooksConfig, elastic, reuseElasticClients, elasticClientConfig, logger)
@@ -266,7 +269,7 @@ var runCmd = &cobra.Command{
 			logger.Error().Err(err).Msg("Failed to run OnNewServer hooks")
 		}
 
-		// Shutdown the server gracefully
+		// Shutdown the server gracefully.
 		var signals []os.Signal
 		signals = append(signals,
 			os.Interrupt,
@@ -283,7 +286,7 @@ var runCmd = &cobra.Command{
 			for sig := range signalsCh {
 				for _, s := range signals {
 					if sig != s {
-						// Notify the hooks that the server is shutting down
+						// Notify the hooks that the server is shutting down.
 						_, err := hooksConfig.Run(
 							context.Background(),
 							map[string]interface{}{"signal": sig.String()},
@@ -302,7 +305,7 @@ var runCmd = &cobra.Command{
 			}
 		}(hooksConfig)
 
-		// Run the server
+		// Run the server.
 		if err := server.Run(); err != nil {
 			logger.Error().Err(err).Msg("Failed to start server")
 		}

gatewayd.yaml

@@ -65,6 +65,3 @@ server:
   reusePort: True
   tcpKeepAlive: 3s # duration
   tcpNoDelay: True
-
-plugins:
-  verificationPolicy: "passdown"

gatewayd_plugins.yaml

@@ -1,5 +1,11 @@
 # Plugin configuration file for GatewayD
 
+plugins:
+  # Possible values: "passdown" (default), "ignore", "abort" and "remove"
+  verificationPolicy: "passdown"
+  # Possible values: "strict" (default) and "loose"
+  compatibilityPolicy: "strict"
+
 # Plugin name
 gatewayd-plugin-test:
   # whether to enable or disable the plugin on the next run
@@ -17,4 +23,4 @@ gatewayd-plugin-test:
     - MAGIC_COOKIE_KEY=GATEWAYD_PLUGIN
     - MAGIC_COOKIE_VALUE=5712b87aa5d7e9f9e9ab643e6603181c5b796015cb1c09d6f5ada882bf2a1872
   # Checksum hash to verify the binary before loading
-  checksum: 006e19bcfd1951e077746143590934470e8b1d67a3904036603013e150fcb708
+  checksum: 09bce5ad90a36a6f3ec0804023098519424289f3d68679159d68e0b08ce70c89

go.mod

@@ -3,6 +3,7 @@ module github.com/gatewayd-io/gatewayd
 go 1.19
 
 require (
+	github.com/Masterminds/semver/v3 v3.2.0
 	github.com/fergusstrange/embedded-postgres v1.19.0
 	github.com/google/go-cmp v0.5.9
 	github.com/hashicorp/go-hclog v1.4.0

go.sum

@@ -2,6 +2,8 @@ cloud.google.com/go v0.26.0/go.mod h1:aQUYkXzVsufM+DwF1aE+0xfcU+56JwCaLick0ClmMT
 cloud.google.com/go v0.34.0/go.mod h1:aQUYkXzVsufM+DwF1aE+0xfcU+56JwCaLick0ClmMTw=
 github.com/BurntSushi/toml v0.3.1 h1:WXkYYl6Yr3qBf1K79EBnL4mak0OimBfB0XUf9Vl28OQ=
 github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
+github.com/Masterminds/semver/v3 v3.2.0 h1:3MEsd0SM6jqZojhjLWWeBY+Kcjy9i6MQAeY7YgDP83g=
+github.com/Masterminds/semver/v3 v3.2.0/go.mod h1:qvl/7zhW3nngYb5+80sSMF+FG2BjYrf8m9wsX0PNOMQ=
 github.com/alecthomas/template v0.0.0-20160405071501-a0175ee3bccc/go.mod h1:LOuyumcjzFXgccqObfd/Ljyb9UuFJ6TxHnclSeseNhc=
 github.com/alecthomas/template v0.0.0-20190718012654-fb15b899a751/go.mod h1:LOuyumcjzFXgccqObfd/Ljyb9UuFJ6TxHnclSeseNhc=
 github.com/alecthomas/units v0.0.0-20151022065526-2efee857e7cf/go.mod h1:ybxpYRFXyAe+OPACYpWeL0wqObRcbAqCMya13uyzqw0=

plugin/registry.go

@@ -3,6 +3,7 @@ package plugin
 import (
 	"context"
 
+	semver "github.com/Masterminds/semver/v3"
 	gerr "github.com/gatewayd-io/gatewayd/errors"
 	"github.com/gatewayd-io/gatewayd/logging"
 	pluginV1 "github.com/gatewayd-io/gatewayd/plugin/v1"
@@ -13,6 +14,8 @@ import (
 	"google.golang.org/protobuf/types/known/structpb"
 )
 
+type CompatPolicy uint
+
 const (
 	DefaultMinPort      uint   = 50000
 	DefaultMaxPort      uint   = 60000
@@ -21,19 +24,26 @@ const (
 	LoggerName          string = "plugin"
 )
 
+const (
+	Strict CompatPolicy = iota
+	Loose
+)
+
 type Registry interface {
 	Add(plugin *Impl) bool
 	Get(id Identifier) *Impl
 	List() []Identifier
+	Exists(name, version, remoteURL string) bool
 	Remove(id Identifier)
 	Shutdown()
 	LoadPlugins(pluginConfig *koanf.Koanf)
 	RegisterHooks(id Identifier)
 }
 
 type RegistryImpl struct {
-	plugins     pool.Pool
-	hooksConfig *HookConfig
+	plugins      pool.Pool
+	hooksConfig  *HookConfig
+	CompatPolicy CompatPolicy
 }
 
 var _ Registry = &RegistryImpl{}
@@ -74,6 +84,40 @@ func (reg *RegistryImpl) List() []Identifier {
 	return plugins
 }
 
+// Exists checks if a plugin exists in the registry.
+func (reg *RegistryImpl) Exists(name, version, remoteURL string) bool {
+	for _, plugin := range reg.List() {
+		if plugin.Name == name && plugin.RemoteURL == remoteURL {
+			// Parse the supplied version and the version in the registry.
+			suppliedVer, err := semver.NewVersion(version)
+			if err != nil {
+				reg.hooksConfig.Logger.Error().Err(err).Msg(
+					"Failed to parse supplied plugin version")
+				return false
+			}
+
+			registryVer, err := semver.NewVersion(plugin.Version)
+			if err != nil {
+				reg.hooksConfig.Logger.Error().Err(err).Msg(
+					"Failed to parse plugin version in registry")
+				return false
+			}
+
+			// Check if the version of the plugin is less than or equal to
+			// the version in the registry.
+			if suppliedVer.LessThan(registryVer) || suppliedVer.Equal(registryVer) {
+				return true
+			}
+
+			reg.hooksConfig.Logger.Debug().Str("name", name).Str("version", version).Msg(
+				"Supplied plugin version is greater than the version in registry")
+			return false
+		}
+	}
+
+	return false
+}
+
 // Remove removes a plugin from the registry.
 func (reg *RegistryImpl) Remove(id Identifier) {
 	reg.plugins.Remove(id)
@@ -105,6 +149,11 @@ func (reg *RegistryImpl) LoadPlugins(pluginConfig *koanf.Koanf) {
 
 	// Add each plugin to the registry.
 	for priority, name := range plugins {
+		// Skip the top-level "plugins" key.
+		if name == "plugins" {
+			continue
+		}
+
 		reg.hooksConfig.Logger.Debug().Str("name", name).Msg("Loading plugin")
 		plugin := &Impl{
 			ID: Identifier{
@@ -209,24 +258,62 @@ func (reg *RegistryImpl) LoadPlugins(pluginConfig *koanf.Koanf) {
 			}
 		}
 
+		// Retrieve plugin requirements.
+		if err := mapstructure.Decode(metadata.Fields["requires"].GetListValue().AsSlice(),
+			&plugin.Requires); err != nil {
+			reg.hooksConfig.Logger.Debug().Err(err).Msg("Failed to decode plugin requirements")
+		}
+
+		// Too many requirements or not enough plugins loaded.
+		if len(plugin.Requires) > reg.plugins.Size() {
+			reg.hooksConfig.Logger.Debug().Msg(
+				"The plugin has too many requirements, " +
+					"and not enough of them exist in the registry, so it won't work properly")
+		}
+
+		// Check if the plugin requirements are met.
+		for _, req := range plugin.Requires {
+			if !reg.Exists(req.Name, req.Version, req.RemoteURL) {
+				reg.hooksConfig.Logger.Debug().Fields(
+					map[string]interface{}{
+						"name":        plugin.ID.Name,
+						"requirement": req.Name,
+					},
+				).Msg("The plugin requirement is not met, so it won't work properly")
+				if reg.CompatPolicy == Strict {
+					reg.hooksConfig.Logger.Debug().Str("name", plugin.ID.Name).Msg(
+						"Registry is in strict compatibility mode, so the plugin won't be loaded")
+					plugin.Stop() // Stop the plugin.
+					continue
+				} else {
+					reg.hooksConfig.Logger.Debug().Fields(
+						map[string]interface{}{
+							"name":        plugin.ID.Name,
+							"requirement": req.Name,
+						},
+					).Msg("Registry is in loose compatibility mode, " +
+						"so the plugin will be loaded anyway")
+				}
+			}
+		}
+
 		plugin.ID.RemoteURL = metadata.Fields["id"].GetStructValue().Fields["remoteUrl"].GetStringValue()
 		plugin.ID.Version = metadata.Fields["id"].GetStructValue().Fields["version"].GetStringValue()
 		plugin.Description = metadata.Fields["description"].GetStringValue()
 		plugin.License = metadata.Fields["license"].GetStringValue()
 		plugin.ProjectURL = metadata.Fields["projectUrl"].GetStringValue()
-		if err := mapstructure.Decode(metadata.Fields["requires"].GetListValue().AsSlice(),
-			&plugin.Requires); err != nil {
-			reg.hooksConfig.Logger.Debug().Err(err).Msg("Failed to decode plugin requirements")
-		}
+		// Retrieve authors.
 		if err := mapstructure.Decode(metadata.Fields["authors"].GetListValue().AsSlice(),
 			&plugin.Authors); err != nil {
 			reg.hooksConfig.Logger.Debug().Err(err).Msg("Failed to decode plugin authors")
 		}
+		// Retrieve hooks.
 		if err := mapstructure.Decode(metadata.Fields["hooks"].GetListValue().AsSlice(),
 			&plugin.Hooks); err != nil {
 			reg.hooksConfig.Logger.Debug().Err(err).Msg("Failed to decode plugin hooks")
 		}
 
+		// Retrieve plugin config.
 		plugin.Config = make(map[string]string)
 		for key, value := range metadata.Fields["config"].GetStructValue().AsMap() {
 			if val, ok := value.(string); ok {