Pass environment variabless to plugins on load

gatewayd_plugins.yaml

@@ -8,5 +8,13 @@ gatewayd-plugin-test:
   localPath: ../gatewayd-plugin-test/gatewayd-plugin-test
   # Pass cmdline args to the plugin
   args: ["--log-level", "info"]
+  # Pass environment variables to the plugin
+  # System-wide environment variables are passed to the plugin normally
+  # and they can be accessed via os.Environ().
+  # Defining any environment variables below will override system-wide environment variables.
+  env:
+    # The below environment variables are used by the plugin loader to verify the plugin's identity.
+    - MAGIC_COOKIE_KEY=GATEWAYD_PLUGIN
+    - MAGIC_COOKIE_VALUE=5712b87aa5d7e9f9e9ab643e6603181c5b796015cb1c09d6f5ada882bf2a1872
   # Checksum hash to verify the binary before loading
-  checksum: a20e3a1529f4460ad24416a055d599f6f55f42ead836345a4bf0a17d056abb45
+  checksum: 1ce8c55e574491871b86f783000e7cfb82f7253b1d3a33a73dffee5fb8af97fe

plugin/plugin.go

@@ -34,6 +34,7 @@ type Impl struct {
 	ProjectURL  string
 	LocalPath   string
 	Args        []string
+	Env         []string
 	Enabled     bool
 	// internal and external config options
 	Config map[string]string

plugin/registry.go

@@ -2,7 +2,6 @@ package plugin
 
 import (
 	"context"
-	"os/exec"
 
 	gerr "github.com/gatewayd-io/gatewayd/errors"
 	"github.com/gatewayd-io/gatewayd/logging"
@@ -133,6 +132,10 @@ func (reg *RegistryImpl) LoadPlugins(pluginConfig *koanf.Koanf) {
 			plugin.Args = args
 		}
 
+		if env := pluginConfig.Strings(name + ".env"); len(env) > 0 {
+			plugin.Env = append(plugin.Env, env...)
+		}
+
 		if checksum, ok := pluginConfig.Get(name + ".checksum").(string); !ok || checksum == "" {
 			reg.hooksConfig.Logger.Debug().Str("name", name).Msg(
 				"Checksum of plugin doesn't exist or is not set")
@@ -167,7 +170,7 @@ func (reg *RegistryImpl) LoadPlugins(pluginConfig *koanf.Koanf) {
 			&goplugin.ClientConfig{
 				HandshakeConfig: pluginV1.Handshake,
 				Plugins:         pluginV1.GetPluginMap(plugin.ID.Name),
-				Cmd:             exec.Command(plugin.LocalPath, plugin.Args...), //nolint:gosec
+				Cmd:             NewCommand(plugin.LocalPath, plugin.Args, plugin.Env),
 				AllowedProtocols: []goplugin.Protocol{
 					goplugin.ProtocolGRPC,
 				},

plugin/utils.go

@@ -7,6 +7,7 @@ import (
 	"fmt"
 	"io"
 	"os"
+	"os/exec"
 
 	gerr "github.com/gatewayd-io/gatewayd/errors"
 	"github.com/google/go-cmp/cmp"
@@ -55,3 +56,12 @@ func Verify(params, returnVal *structpb.Struct) bool {
 		cmpopts.EquateEmpty(),
 	})
 }
+
+// NewCommand returns a command with the given arguments and environment variables.
+func NewCommand(cmd string, args []string, env []string) *exec.Cmd {
+	command := exec.Command(cmd, args...)
+	if env != nil {
+		command.Env = append(command.Env, env...)
+	}
+	return command
+}