API Change - Instance plugin to optionally output instance details (#464)

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

Author: David Chung

cmd/cli/base/output.go

@@ -0,0 +1,41 @@
+package base
+
+import (
+	"fmt"
+	"io"
+
+	"github.com/docker/infrakit/pkg/types"
+	"github.com/ghodss/yaml"
+	"github.com/spf13/pflag"
+)
+
+// RawOutputFunc is a function that writes some data to the output writer
+type RawOutputFunc func(w io.Writer, v interface{}) (rendered bool, err error)
+
+// RawOutput returns the flagset and the func for printing output
+func RawOutput() (*pflag.FlagSet, RawOutputFunc) {
+
+	fs := pflag.NewFlagSet("output", pflag.ExitOnError)
+
+	raw := fs.BoolP("raw", "r", false, "True to dump to output instead of executing")
+	yamlDoc := fs.BoolP("yaml", "y", false, "True if input is in yaml format; json is the default")
+
+	return fs, func(w io.Writer, v interface{}) (rendered bool, err error) {
+		if !*raw {
+			return false, nil
+		}
+
+		any, err := types.AnyValue(v)
+		if err != nil {
+			return false, err
+		}
+
+		buff := any.Bytes()
+		if *yamlDoc {
+			buff, err = yaml.JSONToYAML(buff)
+		}
+
+		fmt.Fprintln(w, string(buff))
+		return true, nil
+	}
+}

cmd/cli/base/template.go

@@ -159,21 +159,6 @@ func TemplateProcessor(plugins func() discovery.Plugins) (*pflag.FlagSet, ToJSON
 				return
 			}
 
-			// if *yamlDoc {
-
-			// 	// Convert this to json if it's not in JSON -- the default is for the template to be in YAML
-			// 	converted, e := yaml.YAMLToJSON([]byte(view))
-			// 	log.Debug("converting yaml to json", "before", view, "after", string(converted))
-
-			// 	if e != nil {
-			// 		err = e
-			// 		return
-			// 	}
-
-			// 	view = string(converted)
-			// 	log.Debug("view", "rendered", view)
-			// }
-
 			log.Debug("rendered", "view", view)
 			if *dump {
 				fmt.Println("Final:")

cmd/cli/instance/instance.go

@@ -1,10 +1,12 @@
 package instance
 
 import (
+	"bytes"
 	"fmt"
 	"os"
 	"sort"
 	"strings"
+	"text/template"
 
 	"github.com/docker/infrakit/cmd/cli/base"
 	"github.com/docker/infrakit/pkg/cli"
@@ -150,8 +152,19 @@ func Command(plugins func() discovery.Plugins) *cobra.Command {
 		Short: "Describe all managed instances across all groups, subject to filter",
 	}
 	tags := describe.Flags().StringSlice("tags", []string{}, "Tags to filter")
+	properties := describe.Flags().BoolP("properties", "p", false, "Also returns current status/ properties")
+	propertiesTemplate := describe.Flags().StringP("view", "v", "{{.}}", "Template to render properties")
+
+	rawOutputFlags, rawOutput := base.RawOutput()
+	describe.Flags().AddFlagSet(rawOutputFlags)
+
 	describe.RunE = func(cmd *cobra.Command, args []string) error {
 
+		view, err := template.New("describe-instances").Parse(*propertiesTemplate)
+		if err != nil {
+			return err
+		}
+
 		filter := map[string]string{}
 		for _, t := range *tags {
 			p := strings.Split(t, "=")
@@ -162,13 +175,28 @@ func Command(plugins func() discovery.Plugins) *cobra.Command {
 			}
 		}
 
-		desc, err := instancePlugin.DescribeInstances(filter)
+		desc, err := instancePlugin.DescribeInstances(filter, *properties)
 		if err == nil {
 
+			rendered, err := rawOutput(os.Stdout, desc)
+			if err != nil {
+				return err
+			}
+
+			if rendered {
+				return nil
+			}
+
 			if !*quiet {
-				fmt.Printf("%-30s\t%-30s\t%-s\n", "ID", "LOGICAL", "TAGS")
+				if *properties {
+					fmt.Printf("%-30s\t%-30s\t%-30s\t%-s\n", "ID", "LOGICAL", "TAGS", "PROPERTIES")
+
+				} else {
+					fmt.Printf("%-30s\t%-30s\t%-s\n", "ID", "LOGICAL", "TAGS")
+				}
 			}
 			for _, d := range desc {
+
 				logical := "  -   "
 				if d.LogicalID != nil {
 					logical = string(*d.LogicalID)
@@ -180,7 +208,12 @@ func Command(plugins func() discovery.Plugins) *cobra.Command {
 				}
 				sort.Strings(printTags)
 
-				fmt.Printf("%-30s\t%-30s\t%-s\n", d.ID, logical, strings.Join(printTags, ","))
+				if *properties {
+					fmt.Printf("%-30s\t%-30s\t%-30s\t%-s\n", d.ID, logical, strings.Join(printTags, ","),
+						renderProperties(d.Properties, view))
+				} else {
+					fmt.Printf("%-30s\t%-30s\t%-s\n", d.ID, logical, strings.Join(printTags, ","))
+				}
 			}
 		}
 
@@ -196,3 +229,18 @@ func Command(plugins func() discovery.Plugins) *cobra.Command {
 
 	return cmd
 }
+
+func renderProperties(properties *types.Any, view *template.Template) string {
+	var v interface{}
+	err := properties.Decode(&v)
+	if err != nil {
+		return err.Error()
+	}
+
+	buff := new(bytes.Buffer)
+	err = view.Execute(buff, v)
+	if err != nil {
+		return err.Error()
+	}
+	return buff.String()
+}

cmd/cli/manager/manager.go

@@ -76,7 +76,7 @@ func Command(plugins func() discovery.Plugins) *cobra.Command {
 			return nil
 		},
 	}
-	pretend := cmd.PersistentFlags().Bool("pretend", true, "Don't actually make changes; explain where appropriate")
+	pretend := cmd.PersistentFlags().Bool("pretend", false, "Don't actually make changes; explain where appropriate")
 
 	///////////////////////////////////////////////////////////////////////////////////
 	// commit

docs/plugins/instance.md

@@ -1,6 +1,6 @@
 # Instance plugin API
 
-<!-- SOURCE-CHECKSUM pkg/spi/instance/* befb47292c2f062637d65e9777d88c322856baf650feb6b527cd3a4242f86d3482b656246051d2ca -->
+<!-- SOURCE-CHECKSUM pkg/spi/instance/* af33b7b157a24a90e4ecef4b99c997a4039edf7832ae259bfe527c06caec5455f3c083481586eda2 -->
 
 ## API
 
@@ -115,21 +115,23 @@ Fetches details about Instances.
 #### Request
 ```json
 {
-  "Tags": {"tag_key": "tag_value"}
+  "Tags": {"tag_key": "tag_value"},
+  "Properties" : true
 }
 ```
 
 Parameters:
 - `Tags`: Instance tags to match.  If multiple tags are specified, only Instances matching all tags are returned.
-
+- `Properties`: Boolean to indicate whether the client requests additional details via the `Description.Properties` field.
 #### Response
 ```json
 {
   "Descriptions": [
     {
       "ID": "instance_id",
       "LogicalID": "logical_id",
-      "Tags": {"tag_key": "tag_value"}
+      "Tags": {"tag_key": "tag_value"},
+      "Properties" : { "some_status" : "ok", "some_state" : 10 }
     }
   ]
 }

examples/instance/file/plugin.go

@@ -142,7 +142,7 @@ func (p *plugin) Destroy(instance instance.ID) error {
 
 // DescribeInstances returns descriptions of all instances matching all of the provided tags.
 // TODO - need to define the fitlering of tags => AND or OR of matches?
-func (p *plugin) DescribeInstances(tags map[string]string) ([]instance.Description, error) {
+func (p *plugin) DescribeInstances(tags map[string]string, properties bool) ([]instance.Description, error) {
 	log.Debugln("describe-instances", tags)
 	entries, err := afero.ReadDir(p.fs, p.Dir)
 	if err != nil {
@@ -166,6 +166,11 @@ scan:
 			continue scan
 		}
 
+		if properties {
+			if blob, err := types.AnyValue(inst.Spec); err == nil {
+				inst.Properties = blob
+			}
+		}
 		if len(tags) == 0 {
 			result = append(result, inst.Description)
 		} else {

examples/instance/file/plugin_test.go

@@ -87,7 +87,7 @@ func run(t *testing.T, properties string) {
 		"label3": "value3",
 	}, parsed.Description.Tags)
 
-	list, err := fileinst.DescribeInstances(map[string]string{"label1": "changed1"})
+	list, err := fileinst.DescribeInstances(map[string]string{"label1": "changed1"}, false)
 	require.NoError(t, err)
 	require.Equal(t, []instance.Description{
 		{
@@ -99,7 +99,7 @@ func run(t *testing.T, properties string) {
 	err = fileinst.Destroy(*id)
 	require.NoError(t, err)
 
-	list, err = fileinst.DescribeInstances(map[string]string{"label1": "changed1"})
+	list, err = fileinst.DescribeInstances(map[string]string{"label1": "changed1"}, false)
 	require.NoError(t, err)
 	require.Equal(t, []instance.Description{}, list)
 

examples/instance/maas/instance.go

@@ -294,7 +294,7 @@ func (m maasPlugin) Destroy(id instance.ID) error {
 }
 
 // DescribeInstances returns descriptions of all instances matching all of the provided tags.
-func (m maasPlugin) DescribeInstances(tags map[string]string) ([]instance.Description, error) {
+func (m maasPlugin) DescribeInstances(tags map[string]string, properties bool) ([]instance.Description, error) {
 	var ret []instance.Description
 	nodeListing := m.MaasObj.GetSubObject("nodes")
 	listNodeObjects, err := nodeListing.CallGet("list", url.Values{})

examples/instance/maas/instance_test.go

@@ -108,7 +108,7 @@ func TestProvision_and_Destroy(t *testing.T) {
 	id, err := maasPlugin.Provision(instanceSpec)
 	require.NoError(t, err)
 
-	list, err := maasPlugin.DescribeInstances(map[string]string{"label1": "value1"})
+	list, err := maasPlugin.DescribeInstances(map[string]string{"label1": "value1"}, false)
 	require.NoError(t, err)
 	require.Equal(t, []instance.Description{
 		{
@@ -125,7 +125,7 @@ func TestProvision_and_Destroy(t *testing.T) {
 	})
 	require.NoError(t, err)
 
-	list, err = maasPlugin.DescribeInstances(map[string]string{"label1": "value1"})
+	list, err = maasPlugin.DescribeInstances(map[string]string{"label1": "value1"}, false)
 	require.NoError(t, err)
 	require.Equal(t, []instance.Description{
 		{
@@ -137,7 +137,7 @@ func TestProvision_and_Destroy(t *testing.T) {
 		},
 	}, list)
 
-	list, err = maasPlugin.DescribeInstances(map[string]string{"label3": "changed"})
+	list, err = maasPlugin.DescribeInstances(map[string]string{"label3": "changed"}, false)
 	require.NoError(t, err)
 	require.Equal(t, []instance.Description{
 		{

examples/instance/terraform/plugin.go

@@ -556,7 +556,7 @@ func (p *plugin) Destroy(instance instance.ID) error {
 }
 
 // DescribeInstances returns descriptions of all instances matching all of the provided tags.
-func (p *plugin) DescribeInstances(tags map[string]string) ([]instance.Description, error) {
+func (p *plugin) DescribeInstances(tags map[string]string, properties bool) ([]instance.Description, error) {
 	log.Debugln("describe-instances", tags)
 
 	show, err := p.terraformShow()