chore(cmd): basic config options with validation

Signed-off-by: Leonardo Grasso <[email protected]>

Author: leogr

cmd/config_options.go

@@ -0,0 +1,55 @@
+/*
+Copyright © 2019 The Falco Authors
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+package cmd
+
+import (
+	"fmt"
+
+	"github.com/creasty/defaults"
+	"github.com/falcosecurity/falcoctl/validate"
+	"github.com/go-playground/validator/v10"
+	logger "github.com/kris-nova/logger"
+)
+
+// ConfigOptions represent the persistent configuration flags of falcoctl.
+type ConfigOptions struct {
+	ConfigFile string `name:"config"`
+	Verbose    int    `validate:"number,min=0,max=4" default:"3" name:"verbose"`
+	Fabulous   bool   `name:"fab"`
+}
+
+// NewConfigOptions creates an instance of ConfigOptions.
+func NewConfigOptions() *ConfigOptions {
+	o := &ConfigOptions{}
+	if err := defaults.Set(o); err != nil {
+		logger.Critical("error setting falcoctl options default")
+	}
+	return o
+}
+
+// Validate validates the ConfigOptions fields.
+func (co *ConfigOptions) Validate() []error {
+	if err := validate.V.Struct(co); err != nil {
+		errors := err.(validator.ValidationErrors)
+		errArr := []error{}
+		for _, e := range errors {
+			// Translate each error one at a time
+			errArr = append(errArr, fmt.Errorf(e.Translate(validate.T)))
+		}
+		return errArr
+	}
+	return nil
+}

cmd/root.go

@@ -17,41 +17,23 @@ limitations under the License.
 package cmd
 
 import (
+	"os"
 	"strings"
 
 	"k8s.io/cli-runtime/pkg/genericclioptions"
 
-	"github.com/falcosecurity/falcoctl/pkg/kubernetes/factory"
 	"github.com/kris-nova/logger"
+	"github.com/mitchellh/go-homedir"
 	"github.com/spf13/cobra"
 	"github.com/spf13/viper"
 )
 
-// RootOptions represents the base command options
-type RootOptions struct {
-	configFlags *genericclioptions.ConfigFlags
-
-	genericclioptions.IOStreams
-
-	fabulous bool
-}
-
-// Validate validates the base command options
-func (o RootOptions) Validate(c *cobra.Command, args []string) error {
-	return nil
-}
-
-// NewRootOptions instantiates the base command options
-func NewRootOptions(streams genericclioptions.IOStreams) CommandOptions {
-	return &RootOptions{
-		configFlags: genericclioptions.NewConfigFlags(false),
-		IOStreams:   streams,
-	}
-}
-
-// New creates the command
+// New creates the faloctl root command
 func New(streams genericclioptions.IOStreams) *cobra.Command {
-	o := NewRootOptions(streams).(*RootOptions)
+	configOptions := NewConfigOptions()
+	cobra.OnInitialize(func() {
+		initConfig(configOptions)
+	})
 
 	cmd := &cobra.Command{
 		Use:                   "falcoctl",
@@ -62,34 +44,65 @@ func New(streams genericclioptions.IOStreams) *cobra.Command {
 			// Set destination for usage and error messages
 			c.SetOutput(streams.ErrOut)
 			// Be fabulous
-			if o.fabulous {
+			if configOptions.Fabulous {
 				logger.Fabulous = true
 				logger.Color = false
 			}
+			logger.Level = configOptions.Verbose
 		},
 		Run: func(c *cobra.Command, args []string) {
 			cobra.NoArgs(c, args)
 			c.Help()
 		},
 	}
 
-	cmd.PersistentFlags().BoolVarP(&o.fabulous, "fab", "f", o.fabulous, "Enable rainbow logs")
-	cmd.PersistentFlags().IntVarP(&logger.Level, "verbose", "v", 3, "Verbosity 0 (off) 4 (most)")
+	cmd.PersistentFlags().StringVarP(&configOptions.ConfigFile, "config", "c", configOptions.ConfigFile, "config file path (default $HOME/.falcoctl.yaml if exists)")
+	cmd.PersistentFlags().BoolVarP(&configOptions.Fabulous, "fab", "f", configOptions.Fabulous, "enable rainbow logs")
+	cmd.PersistentFlags().IntVarP(&configOptions.Verbose, "verbose", "v", configOptions.Verbose, "verbosity 0 (off) 4 (most)")
+
+	cmd.AddCommand(Install(streams))
+	cmd.AddCommand(Delete(streams))
+	cmd.AddCommand(Convert(streams))
 
-	flags := cmd.Flags()
-	o.configFlags.AddFlags(flags)
+	return cmd
+}
 
-	matchVersionFlags := factory.MatchVersion(o.configFlags)
-	matchVersionFlags.AddFlags(flags)
-	f := factory.New(matchVersionFlags)
+// initConfig reads in config file and ENV variables if set.
+func initConfig(configOptions *ConfigOptions) {
+	if errs := configOptions.Validate(); errs != nil {
+		for _, err := range errs {
+			logger.Critical("error validating config options: %s", err)
+		}
+		os.Exit(1)
+	}
+	if configOptions.ConfigFile != "" {
+		viper.SetConfigFile(configOptions.ConfigFile)
+	} else {
+		// Find home directory.
+		home, err := homedir.Dir()
+		if err != nil {
+			logger.Critical("error getting the home directory: %s", err)
+		}
+
+		viper.AddConfigPath(home)
+		viper.SetConfigName(".falcoctl")
+	}
 
 	viper.AutomaticEnv()
 	viper.SetEnvPrefix("falcoctl")
 	viper.SetEnvKeyReplacer(strings.NewReplacer("-", "_"))
-
-	cmd.AddCommand(Install(streams, f))
-	cmd.AddCommand(Delete(streams, f))
-	cmd.AddCommand(Convert(streams))
-
-	return cmd
+	viper.SetEnvKeyReplacer(strings.NewReplacer(".", "_"))
+
+	// If a config file is found, read it in.
+	if err := viper.ReadInConfig(); err == nil {
+		logger.Info("using config file: %s", viper.ConfigFileUsed())
+	} else {
+		if _, ok := err.(viper.ConfigFileNotFoundError); ok {
+			// Config file not found, ignore ...
+			logger.Debug("running without a configuration file")
+		} else {
+			// Config file was found but another error was produced
+			logger.Critical("error running with config file: %s", err)
+		}
+	}
 }

go.mod

@@ -3,11 +3,15 @@ module github.com/falcosecurity/falcoctl
 go 1.13
 
 require (
+	github.com/creasty/defaults v1.3.0
 	github.com/evanphx/json-patch v4.5.0+incompatible // indirect
 	github.com/exponent-io/jsonpath v0.0.0-20151013193312-d6023ce2651d // indirect
 	github.com/fatih/color v1.7.0 // indirect
 	github.com/ghodss/yaml v1.0.0
 	github.com/go-openapi/spec v0.19.3 // indirect
+	github.com/go-playground/locales v0.13.0
+	github.com/go-playground/universal-translator v0.17.0
+	github.com/go-playground/validator/v10 v10.2.0
 	github.com/gogo/protobuf v1.3.0 // indirect
 	github.com/google/btree v1.0.0 // indirect
 	github.com/googleapis/gnostic v0.3.1 // indirect
@@ -18,6 +22,7 @@ require (
 	github.com/kris-nova/lolgopher v0.0.0-20180921204813-313b3abb0d9b // indirect
 	github.com/mattn/go-colorable v0.1.4 // indirect
 	github.com/mattn/go-isatty v0.0.10 // indirect
+	github.com/mitchellh/go-homedir v1.1.0
 	github.com/modern-go/reflect2 v1.0.1 // indirect
 	github.com/peterbourgon/diskv v2.0.1+incompatible // indirect
 	github.com/pkg/errors v0.8.1 // indirect

go.sum

@@ -16,6 +16,8 @@ github.com/coreos/etcd v3.3.10+incompatible/go.mod h1:uF7uidLiAD3TWHmW31ZFd/JWoc
 github.com/coreos/go-etcd v2.0.0+incompatible/go.mod h1:Jez6KQU2B/sWsbdaef3ED8NzMklzPG4d5KIOhIy30Tk=
 github.com/coreos/go-semver v0.2.0/go.mod h1:nnelYz7RCh+5ahJtPPxZlU+153eP4D4r3EedlOD2RNk=
 github.com/cpuguy83/go-md2man v1.0.10/go.mod h1:SmD6nW6nTyfqj6ABTjUi3V3JVMnlJmwcJI5acqYI6dE=
+github.com/creasty/defaults v1.3.0 h1:uG+RAxYbJgOPCOdKEcec9ZJXeva7Y6mj/8egdzwmLtw=
+github.com/creasty/defaults v1.3.0/go.mod h1:CIEEvs7oIVZm30R8VxtFJs+4k201gReYyuYHJxZc68I=
 github.com/davecgh/go-spew v0.0.0-20151105211317-5215b55f46b2/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
@@ -54,6 +56,14 @@ github.com/go-openapi/swag v0.0.0-20160704191624-1d0bd113de87/go.mod h1:DXUve3Dp
 github.com/go-openapi/swag v0.19.2/go.mod h1:POnQmlKehdgb5mhVOsnJFsivZCEZ/vjK9gh66Z9tfKk=
 github.com/go-openapi/swag v0.19.5 h1:lTz6Ys4CmqqCQmZPBlbQENR1/GucA2bzYTE12Pw4tFY=
 github.com/go-openapi/swag v0.19.5/go.mod h1:POnQmlKehdgb5mhVOsnJFsivZCEZ/vjK9gh66Z9tfKk=
+github.com/go-playground/assert/v2 v2.0.1 h1:MsBgLAaY856+nPRTKrp3/OZK38U/wa0CcBYNjji3q3A=
+github.com/go-playground/assert/v2 v2.0.1/go.mod h1:VDjEfimB/XKnb+ZQfWdccd7VUvScMdVu0Titje2rxJ4=
+github.com/go-playground/locales v0.13.0 h1:HyWk6mgj5qFqCT5fjGBuRArbVDfE4hi8+e8ceBS/t7Q=
+github.com/go-playground/locales v0.13.0/go.mod h1:taPMhCMXrRLJO55olJkUXHZBHCxTMfnGwq/HNwmWNS8=
+github.com/go-playground/universal-translator v0.17.0 h1:icxd5fm+REJzpZx7ZfpaD876Lmtgy7VtROAbHHXk8no=
+github.com/go-playground/universal-translator v0.17.0/go.mod h1:UkSxE5sNxxRwHyU+Scu5vgOQjsIJAF8j9muTVoKLVtA=
+github.com/go-playground/validator/v10 v10.2.0 h1:KgJ0snyC2R9VXYN2rneOtQcw5aHQB1Vv0sFl1UcHBOY=
+github.com/go-playground/validator/v10 v10.2.0/go.mod h1:uOYAAleCW8F/7oMFd6aG0GOhaH6EGOAJShg8Id5JGkI=
 github.com/gogo/protobuf v1.3.0 h1:G8O7TerXerS4F6sx9OV7/nRfJdnXgHZu/S/7F2SN+UE=
 github.com/gogo/protobuf v1.3.0/go.mod h1:SlYgWuQ5SjCEi6WLHjHCa1yvBfUnHcTbrrZtXPKa29o=
 github.com/golang/protobuf v0.0.0-20161109072736-4bd1920723d7/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
@@ -92,6 +102,8 @@ github.com/kris-nova/logger v0.0.0-20181127235838-fd0d87064b06 h1:vN4d3jSss3ExzU
 github.com/kris-nova/logger v0.0.0-20181127235838-fd0d87064b06/go.mod h1:++9BgZujZd4v0ZTZCb5iPsaomXdZWyxotIAh1IiDm44=
 github.com/kris-nova/lolgopher v0.0.0-20180921204813-313b3abb0d9b h1:xYEM2oBUhBEhQjrV+KJ9lEWDWYZoNVZUaBF++Wyljq4=
 github.com/kris-nova/lolgopher v0.0.0-20180921204813-313b3abb0d9b/go.mod h1:V0HF/ZBlN86HqewcDC/cVxMmYDiRukWjSrgKLUAn9Js=
+github.com/leodido/go-urn v1.2.0 h1:hpXL4XnriNwQ/ABnpepYM/1vCLWNDfUNts8dX3xTG6Y=
+github.com/leodido/go-urn v1.2.0/go.mod h1:+8+nEpDfqqsY+g338gtMEUOtuK+4dEMhiQEgxpxOKII=
 github.com/magiconair/properties v1.8.0 h1:LLgXmsheXeRoUOBOjtwPQCWIYqM/LU1ayDtDePerRcY=
 github.com/magiconair/properties v1.8.0/go.mod h1:PppfXfuXeibc/6YijjN8zIbojt8czPbwD3XqdrwzmxQ=
 github.com/mailru/easyjson v0.0.0-20160728113105-d5b7844b561a h1:TpvdAwDAt1K4ANVOfcihouRdvP+MgAfDWwBuct4l6ZY=
@@ -150,6 +162,8 @@ github.com/stretchr/testify v0.0.0-20151208002404-e3a8ff8ce365/go.mod h1:a8OnRci
 github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
 github.com/stretchr/testify v1.3.0 h1:TivCn/peBQ7UY8ooIcPgZFpTNSz0Q2U6UrFlUfqbe0Q=
 github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
+github.com/stretchr/testify v1.4.0 h1:2E4SXV/wtOkTonXsotYi4li6zVWxYlZuYNCXe9XRJyk=
+github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
 github.com/ugorji/go/codec v0.0.0-20181204163529-d75b2dcb6bc8/go.mod h1:VFNgLljTbGfSG7qAOspJ7OScBnGdDN/yBr0sguwnwf0=
 github.com/xordataexchange/crypt v0.0.3-0.20170626215501-b2862e3d0a77/go.mod h1:aYKd//L2LvnjZzWKhF00oedf4jCCReLcmhLdhm1A27Q=
 golang.org/x/crypto v0.0.0-20181203042331-505ab145d0a9 h1:mKdxBk7AujPs8kU4m80U72y/zjbZ3UcXC7dClwKbUI0=

validate/validate.go

@@ -0,0 +1,37 @@
+package validate
+
+import (
+	"reflect"
+	"strings"
+
+	"github.com/go-playground/locales/en"
+	ut "github.com/go-playground/universal-translator"
+	"github.com/go-playground/validator/v10"
+	en_translations "github.com/go-playground/validator/v10/translations/en"
+)
+
+// V is the validator single instance.
+//
+// It is a singleton so to cache the structs info.
+var V *validator.Validate
+
+// T is the universal translator for validatiors.
+var T ut.Translator
+
+func init() {
+	V = validator.New()
+
+	// Register a function to get the field name from "name" tags.
+	V.RegisterTagNameFunc(func(fld reflect.StructField) string {
+		name := strings.SplitN(fld.Tag.Get("name"), ",", 2)[0]
+		if name == "-" {
+			return ""
+		}
+		return name
+	})
+
+	eng := en.New()
+	uni := ut.New(eng, eng)
+	T, _ = uni.GetTranslator("en")
+	en_translations.RegisterDefaultTranslations(V, T)
+}