Bootstrapping and resources (#357)

Signed-off-by: Noah Treuhaft <[email protected]>

Author: nwt

Makefile

@@ -115,6 +115,7 @@ endif
 	$(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)
 	$(call build_binary,infrakit-flavor-combo,github.com/docker/infrakit/examples/flavor/combo)
 	$(call build_binary,infrakit-flavor-swarm,github.com/docker/infrakit/examples/flavor/swarm)
 	$(call build_binary,infrakit-flavor-vanilla,github.com/docker/infrakit/examples/flavor/vanilla)

cmd/cli/main.go

@@ -47,7 +47,7 @@ func main() {
 	cmd.AddCommand(eventCommand(f))
 	cmd.AddCommand(pluginCommand(f))
 
-	cmd.AddCommand(instancePluginCommand(f), groupPluginCommand(f), flavorPluginCommand(f))
+	cmd.AddCommand(instancePluginCommand(f), groupPluginCommand(f), flavorPluginCommand(f), resourcePluginCommand(f))
 
 	err := cmd.Execute()
 	if err != nil {

cmd/cli/resource.go

@@ -0,0 +1,168 @@
+package main
+
+import (
+	"fmt"
+	"os"
+
+	log "github.com/Sirupsen/logrus"
+	"github.com/docker/infrakit/pkg/discovery"
+	"github.com/docker/infrakit/pkg/plugin"
+	resource_plugin "github.com/docker/infrakit/pkg/rpc/resource"
+	"github.com/docker/infrakit/pkg/spi/resource"
+	"github.com/docker/infrakit/pkg/template"
+	"github.com/docker/infrakit/pkg/types"
+	"github.com/spf13/cobra"
+)
+
+func resourcePluginCommand(plugins func() discovery.Plugins) *cobra.Command {
+
+	var resourcePlugin resource.Plugin
+
+	cmd := &cobra.Command{
+		Use:   "resource",
+		Short: "Access resource plugin",
+	}
+	name := cmd.PersistentFlags().String("name", "resource", "Name of plugin")
+	cmd.PersistentPreRunE = func(c *cobra.Command, args []string) error {
+		if err := upTree(c, func(x *cobra.Command, argv []string) error {
+			if x.PersistentPreRunE != nil {
+				return x.PersistentPreRunE(x, argv)
+			}
+			return nil
+		}); err != nil {
+			return err
+		}
+
+		endpoint, err := plugins().Find(plugin.Name(*name))
+		if err != nil {
+			return err
+		}
+
+		p, err := resource_plugin.NewClient(endpoint.Address)
+		if err != nil {
+			return err
+		}
+		resourcePlugin = p
+		return nil
+	}
+
+	commit := cobra.Command{
+		Use:   "commit <template URL>",
+		Short: "commit a resource configuration specified by the URL",
+	}
+	commitPretend := commit.Flags().Bool("pretend", false, "Don't actually commit, only explain the commit")
+	commit.RunE = func(cmd *cobra.Command, args []string) error {
+		assertNotNil("no plugin", resourcePlugin)
+
+		if len(args) != 1 {
+			cmd.Usage()
+			os.Exit(1)
+		}
+
+		spec, err := readSpecFromTemplateURL(args[0])
+		if err != nil {
+			return err
+		}
+
+		details, err := resourcePlugin.Commit(*spec, *commitPretend)
+		if err == nil {
+			if *commitPretend {
+				fmt.Printf("Committing %s would involve:\n%s\n", spec.ID, details)
+			} else {
+				fmt.Printf("Committed %s:\n%s\n", spec.ID, details)
+			}
+		}
+		return err
+	}
+	cmd.AddCommand(&commit)
+
+	destroy := cobra.Command{
+		Use:   "destroy <template URL>",
+		Short: "destroy a resource configuration specified by the URL",
+	}
+	destroyPretend := destroy.Flags().Bool("pretend", false, "Don't actually destroy, only explain the destroy")
+	destroy.RunE = func(cmd *cobra.Command, args []string) error {
+		assertNotNil("no plugin", resourcePlugin)
+
+		if len(args) != 1 {
+			cmd.Usage()
+			os.Exit(1)
+		}
+
+		spec, err := readSpecFromTemplateURL(args[0])
+		if err != nil {
+			return err
+		}
+
+		details, err := resourcePlugin.Destroy(*spec, *destroyPretend)
+		if err == nil {
+			if *destroyPretend {
+				fmt.Printf("Destroying %s would involve:\n%s\n", spec.ID, details)
+			} else {
+				fmt.Printf("Destroyed %s:\n%s\n", spec.ID, details)
+			}
+		}
+		return err
+	}
+	cmd.AddCommand(&destroy)
+
+	describe := cobra.Command{
+		Use:   "describe <template URL>",
+		Short: "describe a resource configuration specified by the URL",
+	}
+	describe.RunE = func(cmd *cobra.Command, args []string) error {
+		assertNotNil("no plugin", resourcePlugin)
+
+		if len(args) != 1 {
+			cmd.Usage()
+			os.Exit(1)
+		}
+
+		spec, err := readSpecFromTemplateURL(args[0])
+		if err != nil {
+			return err
+		}
+
+		details, err := resourcePlugin.DescribeResources(*spec)
+		if err == nil {
+			if len(details) > 0 {
+				fmt.Println(details)
+			}
+		}
+		return err
+	}
+	cmd.AddCommand(&describe)
+
+	return cmd
+}
+
+func readSpecFromTemplateURL(templateURL string) (*resource.Spec, error) {
+	log.Infof("Reading template from %v", templateURL)
+	engine, err := template.NewTemplate(templateURL, template.Options{
+		SocketDir: discovery.Dir(),
+	})
+	if err != nil {
+		return nil, err
+	}
+
+	engine.WithFunctions(func() []template.Function {
+		return []template.Function{
+			{Name: "resource", Func: func(s string) string { return fmt.Sprintf("{{ resource `%s` }}", s) }},
+		}
+	})
+
+	view, err := engine.Render(nil)
+	if err != nil {
+		return nil, err
+	}
+
+	log.Debugln(view)
+
+	spec := resource.Spec{}
+	if err := types.AnyString(view).Decode(&spec); err != nil {
+		log.Warningln("Error parsing template")
+		return nil, err
+	}
+
+	return &spec, nil
+}

cmd/resource/README.md

@@ -0,0 +1,69 @@
+InfraKit Resource Plugin
+========================
+
+The Resource plugin works in conjuction with Instance plugins to manage collections of
+interdependent, named resources.  Dependencies are expressed with the `resource "name"` template
+function, the output of which is the ID of the named resource.
+
+## Running
+
+Begin by building plugin [binaries](../../README.md#binaries).
+
+The plugin may be started without any arguments and will default to using unix socket in
+`~/.infrakit/plugins` for communications with the CLI and other plugins:
+
+```shell
+$ build/infrakit-resource
+INFO[0000] Listening at: ~/.infrakit/plugins/resource
+```
+
+## Working with the Resource Plugin
+
+Start the resource plugin as show above.
+
+Start the `instance-file` plugin:
+```shell
+$ mkdir -p instances
+$ build/infrakit-instance-file --dir instances
+INFO[0000] Listening at: ~/.infrakit/plugins/instance-file
+INFO[0000] PID file at ~/.infrakit/plugins/instance-file.pid
+```
+
+Save the following in a file named resources.json.
+```json
+{
+  "ID": "Fancy Resources",
+  "Properties": {
+    "Resources": [
+      {
+        "ID": "A",
+        "Plugin": "instance-file",
+        "Properties": {}
+      },
+      {
+        "ID": "B",
+        "Plugin": "instance-file",
+        "Properties": {
+          "Note": "Depends on {{ resource `A` }}"
+        }
+      }
+    ]
+  }
+}
+```
+
+Commit resources.json:
+```shell
+$ build/infrakit resource commit file:$PWD/resources.json
+INFO[0000] Reading template from file:~/resources.json
+Committed Fancy Resources:
+Provisioned A (instance-9021654729849995625)
+Provisioned B (instance-2978607024592968517)
+```
+
+Verify the presence of `A`'s ID in `B`:
+
+```shell
+$ jq .Spec.Properties.Note instances/instance-2978607024592968517
+"Depends on instance-9021654729849995625"
+```

cmd/resource/main.go

@@ -0,0 +1,57 @@
+package main
+
+import (
+	"os"
+
+	log "github.com/Sirupsen/logrus"
+	"github.com/docker/infrakit/pkg/cli"
+	"github.com/docker/infrakit/pkg/discovery"
+	"github.com/docker/infrakit/pkg/plugin"
+	"github.com/docker/infrakit/pkg/plugin/resource"
+	instance_client "github.com/docker/infrakit/pkg/rpc/instance"
+	resource_server "github.com/docker/infrakit/pkg/rpc/resource"
+	"github.com/docker/infrakit/pkg/spi/instance"
+	"github.com/spf13/cobra"
+)
+
+func main() {
+
+	cmd := &cobra.Command{
+		Use:   os.Args[0],
+		Short: "Resource server",
+	}
+	name := cmd.Flags().String("name", "resource", "Plugin name to advertise for discovery")
+	logLevel := cmd.Flags().Int("log", cli.DefaultLogLevel, "Logging level. 0 is least verbose. Max is 5")
+
+	cmd.RunE = func(c *cobra.Command, args []string) error {
+
+		cli.SetLogLevel(*logLevel)
+
+		plugins, err := discovery.NewPluginDiscovery()
+		if err != nil {
+			return err
+		}
+
+		instancePluginLookup := func(n plugin.Name) (instance.Plugin, error) {
+			endpoint, err := plugins.Find(n)
+			if err != nil {
+				return nil, err
+			}
+			return instance_client.NewClient(n, endpoint.Address)
+		}
+
+		resourcePlugin := resource.NewResourcePlugin(instancePluginLookup)
+
+		cli.RunPlugin(*name, resource_server.PluginServer(resourcePlugin))
+
+		return nil
+	}
+
+	cmd.AddCommand(cli.VersionCommand())
+
+	err := cmd.Execute()
+	if err != nil {
+		log.Error(err)
+		os.Exit(1)
+	}
+}