CLI: only accept configs by path name rather than stdin (docker-archive#229)

Author: wfarner

cmd/cli/README.md

@@ -1,11 +1,8 @@
 InfraKit CLI
 ============
 
-This is a CLI for working with various infrakit plugins.  In the simplest form, an InfraKit plugin
-is simply a daemon that communicates over unix domain sockets.  InfraKit plugins can find each
-other by the socket files in a common directory.  The CLI uses the common directory as a discovery
-mechanism and offers various subcommands for working with plugins. In general, plugin methods are
-exposed as verbs and configuration JSON can be read from local file or standard input.
+This is a developer CLI for working with various _InfraKit_ plugins.  The CLI offers several subcommands for working
+with plugins. In general, plugin methods are exposed as verbs and configuration JSON can be read from local file.
 
 ## Building
 
@@ -24,7 +21,7 @@ instance-file       	~/.infrakit/plugins/instance-file
 ```
 
 Once you know the plugins by name, you can make calls to them.  For example, the instance plugin
-`instance-file` is a simple plugin that "provisions" an instance by writing the instructions to
+`instance-file` is a Plugin that "provisions" instances by writing the instructions to
 a file in a local directory.
 
 You can access the following plugins and their methods via command line:
@@ -37,89 +34,35 @@ You can access the following plugins and their methods via command line:
 
 Using the plugin `instance-file` as an example:
 
-`describe` calls the `DescribeInstances` endpoint of the plugin:
+### Validate
 
 ```
-$ build/infrakit instance --name instance-file describe
-ID                            	LOGICAL                       	TAGS
-instance-1474850397           	  -                           	group=test,instanceType=small
-instance-1474850412           	  -                           	group=test2,instanceType=small
-instance-1474851747           	logic2                        	instanceType=small,group=test2
-```
-
-Validate - send the config JSON via stdin:
-
-```
-$ build/infrakit instance --name instance-file validate << EOF
-> {
->     "Properties" : {
->         "version" : "v0.0.1",
->         "groups" : {
->             "managers" : {
->                 "driver" : "infrakit/quorum"
->             },
->             "small" : {
->                 "driver" : "infrakit/scaler",
->                 "properties" : {
->                     "size" : 3
->                 }
->             },
->             "large" : {
->                 "driver" : "infrakit/scaler",
->                 "properties" : {
->                     "size" : 3
->                 }
->             }
->         }
->     },
->     "Tags" : {
->         "instanceType" : "small",
->         "group" : "test2"
->     },
->     "Init" : "#!/bin/sh\napt-get install -y wget",
->     "LogicalID" : "logic2"
-> }
-> EOF
+$ cat << EOF > instance.json
+{
+    "Properties": {
+        "version": "v0.0.1"
+    },
+    "Tags": {
+        "instanceType": "small",
+        "group": "test2"
+    },
+    "Init": "#!/bin/sh\napt-get install -y wget",
+    "LogicalID": "logic2"
+}
+EOF
+
+$ build/infrakit instance --name instance-file instance.json
 validate:ok
 ```
 
-Provision - send via stdin:
+### Provision
 
 ```
-$ build/infrakit instance --name instance-file provision << EOF
-> {
->     "Properties" : {
->         "version" : "v0.0.1",
->         "groups" : {
->             "managers" : {
->                 "driver" : "infrakit/quorum"
->             },
->             "small" : {
->                 "driver" : "infrakit/scaler",
->                 "properties" : {
->                     "size" : 3
->                 }
->             },
->             "large" : {
->                 "driver" : "infrakit/scaler",
->                 "properties" : {
->                     "size" : 3
->                 }
->             }
->         }
->     },
->     "Tags" : {
->         "instanceType" : "small",
->         "group" : "test2"
->     },
->     "Init" : "#!/bin/sh\napt-get install -y wget",
->     "LogicalID" : "logic2"
-> }
-> EOF
+$ build/infrakit instance --name instance-file provision instance.json
 instance-1474873473
 ```
 
-List instances
+### List instances
 
 ```
 $ build/infrakit instance --name instance-file describe
@@ -129,7 +72,8 @@ instance-1474850412           	  -                           	group=test2,instan
 instance-1474851747           	logic2                        	group=test2,instanceType=small
 instance-1474873473           	logic2                        	group=test2,instanceType=small
 ```
-Destroy
+
+### Destroy
 
 ```
 $ build/infrakit instance --name instance-file destroy instance-1474873473

cmd/cli/flavor.go

@@ -3,13 +3,15 @@ package main
 import (
 	"encoding/json"
 	"fmt"
-	"strings"
-
+	log "github.com/Sirupsen/logrus"
 	"github.com/docker/infrakit/discovery"
 	"github.com/docker/infrakit/spi/flavor"
 	flavor_plugin "github.com/docker/infrakit/spi/http/flavor"
 	"github.com/docker/infrakit/spi/instance"
 	"github.com/spf13/cobra"
+	"io/ioutil"
+	"os"
+	"strings"
 )
 
 func flavorPluginCommand(plugins func() discovery.Plugins) *cobra.Command {
@@ -34,12 +36,23 @@ func flavorPluginCommand(plugins func() discovery.Plugins) *cobra.Command {
 	cmd.PersistentFlags().StringVar(&name, "name", name, "Name of plugin")
 
 	validate := &cobra.Command{
-		Use:   "validate",
-		Short: "validate input",
+		Use:   "validate <flavor configuration file>",
+		Short: "validate a flavor configuration",
 		RunE: func(cmd *cobra.Command, args []string) error {
 			assertNotNil("no plugin", flavorPlugin)
 
-			alloc, err := flavorPlugin.Validate(json.RawMessage(getInput(args)))
+			if len(args) != 1 {
+				cmd.Usage()
+				os.Exit(1)
+			}
+
+			buff, err := ioutil.ReadFile(args[0])
+			if err != nil {
+				log.Error(err)
+				os.Exit(1)
+			}
+
+			alloc, err := flavorPlugin.Validate(json.RawMessage(buff))
 			if err == nil {
 				if buff, err2 := json.MarshalIndent(alloc, "  ", "  "); err2 == nil {
 					fmt.Println("validate", string(buff))
@@ -53,22 +66,34 @@ func flavorPluginCommand(plugins func() discovery.Plugins) *cobra.Command {
 
 	flavorPropertiesFile := ""
 	prepare := &cobra.Command{
-		Use:   "prepare",
-		Short: "prepare the provision data",
+		Use:   "prepare  <instance Spec JSON file>",
+		Short: "prepare provisioning inputs for an instance",
 		RunE: func(cmd *cobra.Command, args []string) error {
 			assertNotNil("no plugin", flavorPlugin)
 
-			buff := getInput(args)
-			spec := instance.Spec{}
-			err := json.Unmarshal(buff, &spec)
+			if len(args) != 1 {
+				cmd.Usage()
+				os.Exit(1)
+			}
+
+			buff, err := ioutil.ReadFile(args[0])
 			if err != nil {
+				log.Error(err)
+				os.Exit(1)
+			}
+
+			spec := instance.Spec{}
+			if err := json.Unmarshal(buff, &spec); err != nil {
 				return err
 			}
 
-			// the flavor's config is in a flag.
-			buffFlavor := getInput([]string{flavorPropertiesFile})
+			buff, err = ioutil.ReadFile(args[0])
+			if err != nil {
+				log.Error(err)
+				os.Exit(1)
+			}
 
-			spec, err = flavorPlugin.Prepare(json.RawMessage(buffFlavor), spec)
+			spec, err = flavorPlugin.Prepare(json.RawMessage(buff), spec)
 			if err == nil {
 				buff, err = json.MarshalIndent(spec, "  ", "  ")
 				if err == nil {
@@ -78,14 +103,18 @@ func flavorPluginCommand(plugins func() discovery.Plugins) *cobra.Command {
 			return err
 		},
 	}
-	prepare.Flags().StringVar(&flavorPropertiesFile, "properties", flavorPropertiesFile, "Path to flavor properties")
+	prepare.Flags().StringVar(
+		&flavorPropertiesFile,
+		"properties",
+		flavorPropertiesFile,
+		"Path to flavor properties")
 
 	tags := []string{}
 	id := ""
 	logicalID := ""
 	healthy := &cobra.Command{
 		Use:   "healthy",
-		Short: "checks for health",
+		Short: "checks if an instance is considered healthy",
 		RunE: func(cmd *cobra.Command, args []string) error {
 			assertNotNil("no plugin", flavorPlugin)