Revert #173 and #139, reinstating having a config file.

docs/cmd/kn.md

@@ -13,6 +13,7 @@ Eventing: Manage event subscriptions and channels. Connect up event sources.
 ### Options
 
 ```
+      --config string       config file (default is $HOME/.kn/config.yaml)
   -h, --help                help for kn
       --kubeconfig string   kubectl config file (default is $HOME/.kube/config)
 ```

docs/cmd/kn_completion.md

@@ -20,6 +20,7 @@ kn completion [flags]
 ### Options inherited from parent commands
 
 ```
+      --config string       config file (default is $HOME/.kn/config.yaml)
       --kubeconfig string   kubectl config file (default is $HOME/.kube/config)
 ```
 

docs/cmd/kn_revision.md

@@ -15,6 +15,7 @@ Revision command group
 ### Options inherited from parent commands
 
 ```
+      --config string       config file (default is $HOME/.kn/config.yaml)
       --kubeconfig string   kubectl config file (default is $HOME/.kube/config)
 ```
 

docs/cmd/kn_revision_describe.md

@@ -23,6 +23,7 @@ kn revision describe NAME [flags]
 ### Options inherited from parent commands
 
 ```
+      --config string       config file (default is $HOME/.kn/config.yaml)
       --kubeconfig string   kubectl config file (default is $HOME/.kube/config)
 ```
 

docs/cmd/kn_revision_list.md

@@ -24,6 +24,7 @@ kn revision list [flags]
 ### Options inherited from parent commands
 
 ```
+      --config string       config file (default is $HOME/.kn/config.yaml)
       --kubeconfig string   kubectl config file (default is $HOME/.kube/config)
 ```
 

docs/cmd/kn_service.md

@@ -15,6 +15,7 @@ Service command group
 ### Options inherited from parent commands
 
 ```
+      --config string       config file (default is $HOME/.kn/config.yaml)
       --kubeconfig string   kubectl config file (default is $HOME/.kube/config)
 ```
 

docs/cmd/kn_service_create.md

@@ -54,6 +54,7 @@ kn service create NAME --image IMAGE [flags]
 ### Options inherited from parent commands
 
 ```
+      --config string       config file (default is $HOME/.kn/config.yaml)
       --kubeconfig string   kubectl config file (default is $HOME/.kube/config)
 ```
 

docs/cmd/kn_service_delete.md

@@ -31,6 +31,7 @@ kn service delete NAME [flags]
 ### Options inherited from parent commands
 
 ```
+      --config string       config file (default is $HOME/.kn/config.yaml)
       --kubeconfig string   kubectl config file (default is $HOME/.kube/config)
 ```
 

docs/cmd/kn_service_describe.md

@@ -23,6 +23,7 @@ kn service describe NAME [flags]
 ### Options inherited from parent commands
 
 ```
+      --config string       config file (default is $HOME/.kn/config.yaml)
       --kubeconfig string   kubectl config file (default is $HOME/.kube/config)
 ```
 

docs/cmd/kn_service_list.md

@@ -24,6 +24,7 @@ kn service list [flags]
 ### Options inherited from parent commands
 
 ```
+      --config string       config file (default is $HOME/.kn/config.yaml)
       --kubeconfig string   kubectl config file (default is $HOME/.kube/config)
 ```
 

docs/cmd/kn_service_update.md

@@ -41,6 +41,7 @@ kn service update NAME [flags]
 ### Options inherited from parent commands
 
 ```
+      --config string       config file (default is $HOME/.kn/config.yaml)
       --kubeconfig string   kubectl config file (default is $HOME/.kube/config)
 ```
 

docs/cmd/kn_version.md

@@ -19,6 +19,7 @@ kn version [flags]
 ### Options inherited from parent commands
 
 ```
+      --config string       config file (default is $HOME/.kn/config.yaml)
       --kubeconfig string   kubectl config file (default is $HOME/.kube/config)
 ```
 

go.mod

@@ -29,7 +29,7 @@ require (
 	github.com/peterbourgon/diskv v2.0.1+incompatible // indirect
 	github.com/spf13/cobra v0.0.3
 	github.com/spf13/pflag v1.0.3
-	github.com/spf13/viper v1.3.1 // indirect
+	github.com/spf13/viper v1.3.1
 	github.com/stretchr/objx v0.2.0 // indirect
 	go.uber.org/atomic v1.4.0 // indirect
 	go.uber.org/multierr v1.1.0 // indirect

pkg/kn/commands/test_helper.go

@@ -55,6 +55,7 @@ Eventing: Manage event subscriptions and channels. Connect up event sources.`,
 	if params.Output != nil {
 		rootCmd.SetOutput(params.Output)
 	}
+	rootCmd.PersistentFlags().StringVar(&CfgFile, "config", "", "config file (default is $HOME/.kn.yaml)")
 	rootCmd.PersistentFlags().StringVar(&KubeCfgFile, "kubeconfig", "", "kubectl config file (default is $HOME/.kube/config)")
 
 	rootCmd.AddCommand(subCommand)

pkg/kn/commands/types.go

@@ -21,6 +21,9 @@ import (
 	"k8s.io/client-go/tools/clientcmd"
 )
 
+// CfgFile is Kn's config file is the path for the Kubernetes config
+var CfgFile string
+
 // KubeCfgFile is the path for the Kubernetes config
 var KubeCfgFile string
 

pkg/kn/core/root.go

@@ -18,13 +18,15 @@ import (
 	"flag"
 	"fmt"
 	"os"
+	"path"
 	"path/filepath"
 
 	"github.com/knative/client/pkg/kn/commands"
 	"github.com/knative/client/pkg/kn/commands/revision"
 	"github.com/knative/client/pkg/kn/commands/service"
 	homedir "github.com/mitchellh/go-homedir"
 	"github.com/spf13/cobra"
+	"github.com/spf13/viper"
 	_ "k8s.io/client-go/plugin/pkg/client/auth/gcp"
 	_ "k8s.io/client-go/plugin/pkg/client/auth/oidc"
 )
@@ -62,6 +64,7 @@ Eventing: Manage event subscriptions and channels. Connect up event sources.`,
 	if p.Output != nil {
 		rootCmd.SetOutput(p.Output)
 	}
+	rootCmd.PersistentFlags().StringVar(&commands.CfgFile, "config", "", "config file (default is $HOME/.kn/config.yaml)")
 	rootCmd.PersistentFlags().StringVar(&commands.KubeCfgFile, "kubeconfig", "", "kubectl config file (default is $HOME/.kube/config)")
 
 	rootCmd.AddCommand(service.NewServiceCommand(p))
@@ -75,7 +78,9 @@ Eventing: Manage event subscriptions and channels. Connect up event sources.`,
 }
 
 func InitializeConfig() {
+	cobra.OnInitialize(initConfig)
 	cobra.OnInitialize(initKubeConfig)
+
 }
 
 func initKubeConfig() {
@@ -93,3 +98,29 @@ func initKubeConfig() {
 		commands.KubeCfgFile = filepath.Join(home, ".kube", "config")
 	}
 }
+
+// initConfig reads in config file and ENV variables if set.
+func initConfig() {
+	if commands.CfgFile != "" {
+		// Use config file from the flag.
+		viper.SetConfigFile(commands.CfgFile)
+	} else {
+		// Find home directory.
+		home, err := homedir.Dir()
+		if err != nil {
+			fmt.Fprintln(os.Stderr, err)
+			os.Exit(1)
+		}
+
+		// Search config in home directory with name ".kn" (without extension).
+		viper.AddConfigPath(path.Join(home, ".kn"))
+		viper.SetConfigName("config")
+	}
+
+	viper.AutomaticEnv() // read in environment variables that match
+
+	// If a config file is found, read it in.
+	if err := viper.ReadInConfig(); err == nil {
+		fmt.Fprintln(os.Stderr, "Using config file:", viper.ConfigFileUsed())
+	}
+}