Updatable SPI (#491)

Signed-off-by: David Chung <david.chung@docker.com>

Author: David Chung

Makefile

@@ -119,7 +119,7 @@ ifneq (,$(findstring .m,$(VERSION)))
 	@echo "\nWARNING - repository contains uncommitted changes, tagging binaries as dirty\n"
 endif
 
-	$(call build_binary,infrakit,github.com/docker/infrakit/cmd/cli/main)
+	$(call build_binary,infrakit,github.com/docker/infrakit/cmd/cli)
 	$(call build_binary,infrakit-manager,github.com/docker/infrakit/cmd/manager)
 	$(call build_binary,infrakit-group-default,github.com/docker/infrakit/cmd/group)
 	$(call build_binary,infrakit-resource,github.com/docker/infrakit/cmd/resource)
@@ -142,7 +142,7 @@ build-cli:
 ifneq (,$(findstring .m,$(VERSION)))
 	@echo "\nWARNING - repository contains uncommitted changes, tagging binaries as dirty\n"
 endif
-	$(call build_binary,infrakit,github.com/docker/infrakit/cmd/cli/main)
+	$(call build_binary,infrakit,github.com/docker/infrakit/cmd/cli)
 
 install:
 	@echo "+ $@"

cmd/cli/main/main.go renamed to cmd/cli/main.go

@@ -19,8 +19,10 @@ import (
 	_ "github.com/docker/infrakit/cmd/cli/event"
 	_ "github.com/docker/infrakit/cmd/cli/flavor"
 	_ "github.com/docker/infrakit/cmd/cli/group"
+	_ "github.com/docker/infrakit/cmd/cli/info"
+	_ "github.com/docker/infrakit/cmd/cli/instance"
 	_ "github.com/docker/infrakit/cmd/cli/manager"
-	_ "github.com/docker/infrakit/cmd/cli/playbook"
+	_ "github.com/docker/infrakit/cmd/cli/metadata"
 	_ "github.com/docker/infrakit/cmd/cli/plugin"
 	_ "github.com/docker/infrakit/cmd/cli/resource"
 	_ "github.com/docker/infrakit/cmd/cli/template"

cmd/cli/main/init.go

@@ -1,8 +1,11 @@
 package manager
 
 import (
+	"bufio"
 	"fmt"
 	"os"
+	"strconv"
+	"strings"
 
 	"github.com/docker/infrakit/cmd/cli/base"
 	"github.com/docker/infrakit/pkg/cli"
@@ -11,10 +14,13 @@ import (
 	"github.com/docker/infrakit/pkg/manager"
 	"github.com/docker/infrakit/pkg/plugin"
 	"github.com/docker/infrakit/pkg/rpc/client"
-	group_plugin "github.com/docker/infrakit/pkg/rpc/group"
+	group_rpc "github.com/docker/infrakit/pkg/rpc/group"
 	manager_rpc "github.com/docker/infrakit/pkg/rpc/manager"
+	metadata_rpc "github.com/docker/infrakit/pkg/rpc/metadata"
 	"github.com/docker/infrakit/pkg/spi/group"
+	"github.com/docker/infrakit/pkg/spi/metadata"
 	"github.com/docker/infrakit/pkg/types"
+	"github.com/sergi/go-diff/diffmatchpatch"
 	"github.com/spf13/cobra"
 )
 
@@ -30,6 +36,9 @@ func Command(plugins func() discovery.Plugins) *cobra.Command {
 	var groupPlugin group.Plugin
 	var groupPluginName string
 
+	var updatablePlugin metadata.Updatable
+	var updatablePluginName string
+
 	cmd := &cobra.Command{
 		Use:   "manager",
 		Short: "Access the manager",
@@ -59,11 +68,15 @@ func Command(plugins func() discovery.Plugins) *cobra.Command {
 					log.Debug("Found manager", "name", name, "leader", isLeader)
 					if isLeader {
 
-						groupPlugin = group_plugin.Adapt(rpcClient)
+						groupPlugin = group_rpc.Adapt(rpcClient)
 						groupPluginName = name
 
 						log.Debug("Found manager", "name", name, "addr", endpoint.Address)
 
+						updatablePlugin = metadata_rpc.AdaptUpdatable(rpcClient)
+						updatablePluginName = name
+
+						log.Debug("Found updatable", "name", name, "addr", endpoint.Address)
 						break
 					}
 				}
@@ -132,7 +145,7 @@ func Command(plugins func() discovery.Plugins) *cobra.Command {
 
 				// TODO(chungers) -- we need to enforce and confirm the type of this.
 				// Right now we assume the RPC endpoint is indeed a group.
-				target, err := group_plugin.NewClient(endpoint.Address)
+				target, err := group_rpc.NewClient(endpoint.Address)
 
 				log.Debug("commit", "plugin", gp.Plugin, "address", endpoint.Address, "err", err, "spec", spec)
 
@@ -165,26 +178,11 @@ func Command(plugins func() discovery.Plugins) *cobra.Command {
 				os.Exit(1)
 			}
 
-			specs, err := groupPlugin.InspectGroups()
+			out, err := getGlobalConfig(groupPlugin, groupPluginName)
 			if err != nil {
 				return err
 			}
 
-			// the format is plugin.Spec
-			out := []plugin.Spec{}
-			for _, spec := range specs {
-
-				any, err := types.AnyValue(spec)
-				if err != nil {
-					return err
-				}
-
-				out = append(out, plugin.Spec{
-					Plugin:     plugin.Name(groupPluginName),
-					Properties: any,
-				})
-			}
-
 			view, err := types.AnyValue(out)
 			if err != nil {
 				return err
@@ -202,7 +200,181 @@ func Command(plugins func() discovery.Plugins) *cobra.Command {
 	}
 	inspect.Flags().AddFlagSet(templateFlags)
 
-	cmd.AddCommand(commit, inspect)
+	///////////////////////////////////////////////////////////////////////////////////
+	// change
+	change := &cobra.Command{
+		Use:   "change",
+		Short: "Change returns the plugin configurations known by the manager",
+	}
+	vars := change.Flags().StringSliceP("var", "v", []string{}, "key=value pairs")
+	commitChange := change.Flags().BoolP("commit", "c", false, "Commit changes")
+
+	// This is the only interactive command.  We want to show the user the proposal, with the diff
+	// and when the user accepts the change, call a commit.
+	change.RunE = func(cmd *cobra.Command, args []string) error {
+
+		if len(args) != 0 {
+			cmd.Usage()
+			os.Exit(1)
+		}
+
+		log.Info("applying changes")
+
+		// get the changes
+		changes, err := changeSet(*vars)
+		if err != nil {
+			return err
+		}
+		current, proposed, cas, err := updatablePlugin.Changes(changes)
+		if err != nil {
+			return err
+		}
+		currentBuff, err := current.MarshalYAML()
+		if err != nil {
+			return err
+		}
+
+		proposedBuff, err := proposed.MarshalYAML()
+		if err != nil {
+			return err
+		}
+
+		// render the proposal
+		fmt.Printf("Proposed changes, hash=%s\n", cas)
+		dmp := diffmatchpatch.New()
+		diffs := dmp.DiffMain(string(currentBuff), string(proposedBuff), false)
+		fmt.Println(dmp.DiffPrettyText(diffs))
+
+		if *commitChange {
+			// ask for final approval
+			input := bufio.NewReader(os.Stdin)
+			fmt.Fprintf(os.Stderr, "\n\nCommit? [y/n] ")
+			text, _ := input.ReadString('\n')
+			text = strings.Trim(text, " \t\n")
+
+			agree, err := parseBool(text)
+			if err != nil {
+				return fmt.Errorf("not boolean %v", text)
+			}
+			if !agree {
+				fmt.Fprintln(os.Stderr, "Not committing. Bye.")
+				os.Exit(0)
+			}
+
+			return updatablePlugin.Commit(proposed, cas)
+		}
+
+		return nil
+	}
+	change.Flags().AddFlagSet(templateFlags)
+
+	///////////////////////////////////////////////////////////////////////////////////
+	// change-list
+	changeList := &cobra.Command{
+		Use:   "ls",
+		Short: "Lists all the changeable paths",
+		RunE: func(cmd *cobra.Command, args []string) error {
+
+			if len(args) != 0 {
+				cmd.Usage()
+				os.Exit(1)
+			}
+
+			all, err := types.ListAll(updatablePlugin, types.PathFromString("."))
+			if err != nil {
+				return err
+			}
+
+			types.Sort(all)
+			for _, p := range all {
+				fmt.Println(p.String())
+			}
+			return nil
+		},
+	}
+	///////////////////////////////////////////////////////////////////////////////////
+	// change-cat
+	changeGet := &cobra.Command{
+		Use:   "cat",
+		Short: "Cat returns the current value at given path",
+		RunE: func(cmd *cobra.Command, args []string) error {
+
+			if len(args) != 1 {
+				cmd.Usage()
+				os.Exit(1)
+			}
+
+			path := types.PathFromString(args[0])
+			any, err := updatablePlugin.Get(path)
+			if err != nil {
+				return err
+			}
+
+			fmt.Println(any.String())
+
+			return nil
+		},
+	}
+	change.AddCommand(changeList, changeGet)
+
+	cmd.AddCommand(commit, inspect, change)
 
 	return cmd
 }
+
+func parseBool(text string) (bool, error) {
+	agree, err := strconv.ParseBool(text)
+	if err == nil {
+		return agree, nil
+	}
+	switch strings.ToLower(text) {
+	case "yes", "ok", "y":
+		return true, nil
+	case "no", "nope", "n":
+		return false, nil
+	}
+	return false, err
+}
+
+func getGlobalConfig(groupPlugin group.Plugin, groupPluginName string) ([]plugin.Spec, error) {
+	specs, err := groupPlugin.InspectGroups()
+	if err != nil {
+		return nil, err
+	}
+
+	// the format is plugin.Spec
+	out := []plugin.Spec{}
+	for _, spec := range specs {
+
+		any, err := types.AnyValue(spec)
+		if err != nil {
+			return nil, err
+		}
+
+		out = append(out, plugin.Spec{
+			Plugin:     plugin.Name(groupPluginName),
+			Properties: any,
+		})
+	}
+	return out, nil
+}
+
+// changeSet returns a set of changes from the input pairs of path / value
+func changeSet(kvPairs []string) ([]metadata.Change, error) {
+	changes := []metadata.Change{}
+
+	for _, kv := range kvPairs {
+
+		parts := strings.SplitN(kv, "=", 2)
+		key := strings.Trim(parts[0], " \t\n")
+		value := strings.Trim(parts[1], " \t\n")
+
+		change := metadata.Change{
+			Path:  types.PathFromString(key),
+			Value: types.AnyYAMLMust([]byte(value)),
+		}
+
+		changes = append(changes, change)
+	}
+	return changes, nil
+}