Support Template Data in Results

component/component.go

@@ -171,3 +171,14 @@ type Release interface {
 	// URL is the URL to access this release.
 	URL() string
 }
+
+// Template can be implemented by Artifact, Deployment, and Release. This
+// will expose this information as available variables in the HCL configuration
+// as well as functions in the `template`-prefixed family, such as `templatefile`.
+//
+// If Template is NOT implemented, we will automatically infer template data
+// based on exported variables of the result value. This may not be desirable
+// in which case you should implement Template and return nil.
+type Template interface {
+	TemplateData() map[string]interface{}
+}

go.mod

@@ -14,6 +14,7 @@ require (
 	github.com/hashicorp/go-hclog v0.14.1
 	github.com/hashicorp/go-plugin v1.3.0
 	github.com/hashicorp/hcl/v2 v2.6.0
+	github.com/iancoleman/strcase v0.1.2
 	github.com/lab47/vterm v0.0.0-20201001232628-a9dd795f94c2
 	github.com/mattn/go-colorable v0.1.8
 	github.com/mattn/go-isatty v0.0.12

go.sum

@@ -82,6 +82,8 @@ github.com/hashicorp/hcl/v2 v2.6.0 h1:3krZOfGY6SziUXa6H9PJU6TyohHn7I+ARYnhbeNBz+
 github.com/hashicorp/hcl/v2 v2.6.0/go.mod h1:bQTN5mpo+jewjJgh8jr0JUguIi7qPHUF6yIfAEN3jqY=
 github.com/hashicorp/yamux v0.0.0-20180604194846-3520598351bb h1:b5rjCoWHc7eqmAS4/qyk21ZsHyb6Mxv/jykxvNTkU4M=
 github.com/hashicorp/yamux v0.0.0-20180604194846-3520598351bb/go.mod h1:+NfK9FKeTrX5uv1uIXGdwYDTeHna2qgaIlx54MXqjAM=
+github.com/iancoleman/strcase v0.1.2 h1:gnomlvw9tnV3ITTAxzKSgTF+8kFWcU/f+TgttpXGz1U=
+github.com/iancoleman/strcase v0.1.2/go.mod h1:SK73tn/9oHe+/Y0h39VT4UCxmurVJkR5NA7kMEAOgSE=
 github.com/jhump/protoreflect v1.6.0 h1:h5jfMVslIg6l29nsMs0D8Wj17RDVdNYti0vDN/PZZoE=
 github.com/jhump/protoreflect v1.6.0/go.mod h1:eaTn3RZAmMBcV0fifFvlm6VHNz3wSkYyXYWUh7ymB74=
 github.com/kr/pretty v0.1.0 h1:L/CwN0zerZDmRFUapSPitk6f+Q3+0za1rQkzVuMiMFI=

internal/plugin/builder.go

@@ -2,6 +2,7 @@ package plugin
 
 import (
 	"context"
+	"encoding/json"
 
 	"github.com/golang/protobuf/ptypes/empty"
 	"github.com/hashicorp/go-argmapper"
@@ -135,8 +136,19 @@ func (c *builderClient) build(
 		return nil, err
 	}
 
+	var tplData map[string]interface{}
+	if len(resp.TemplateData) > 0 {
+		if err := json.Unmarshal(resp.TemplateData, &tplData); err != nil {
+			return nil, err
+		}
+	}
+
 	// We return the
-	return &plugincomponent.Artifact{Any: resp.Result, LabelsVal: resp.Labels}, nil
+	return &plugincomponent.Artifact{
+		Any:         resp.Result,
+		LabelsVal:   resp.Labels,
+		TemplateVal: tplData,
+	}, nil
 }
 
 // builderServer is a gRPC server that the client talks to and calls a
@@ -206,6 +218,11 @@ func (s *builderServer) Build(
 		result.Labels = artifact.Labels()
 	}
 
+	result.TemplateData, err = templateData(raw)
+	if err != nil {
+		return nil, err
+	}
+
 	return result, nil
 }
 

internal/plugin/platform.go

@@ -2,6 +2,7 @@ package plugin
 
 import (
 	"context"
+	"encoding/json"
 	"reflect"
 
 	"github.com/davecgh/go-spew/spew"
@@ -239,7 +240,17 @@ func (c *platformClient) deploy(
 		return nil, err
 	}
 
-	return &plugincomponent.Deployment{Any: resp.Result}, nil
+	var tplData map[string]interface{}
+	if len(resp.TemplateData) > 0 {
+		if err := json.Unmarshal(resp.TemplateData, &tplData); err != nil {
+			return nil, err
+		}
+	}
+
+	return &plugincomponent.Deployment{
+		Any:         resp.Result,
+		TemplateVal: tplData,
+	}, nil
 }
 
 func (c *platformClient) DefaultReleaserFunc() interface{} {
@@ -362,7 +373,7 @@ func (s *platformServer) Deploy(
 	internal := s.internal()
 	defer internal.Cleanup.Close()
 
-	encoded, _, err := callDynamicFuncAny2(s.Impl.DeployFunc(), args.Args,
+	encoded, raw, err := callDynamicFuncAny2(s.Impl.DeployFunc(), args.Args,
 		argmapper.ConverterFunc(s.Mappers...),
 		argmapper.Typed(internal),
 		argmapper.Typed(ctx),
@@ -371,7 +382,13 @@ func (s *platformServer) Deploy(
 		return nil, err
 	}
 
-	return &proto.Deploy_Resp{Result: encoded}, nil
+	result := &proto.Deploy_Resp{Result: encoded}
+	result.TemplateData, err = templateData(raw)
+	if err != nil {
+		return nil, err
+	}
+
+	return result, nil
 }
 
 func (s *platformServer) DefaultReleaserSpec(

internal/plugin/registry.go

@@ -2,6 +2,7 @@ package plugin
 
 import (
 	"context"
+	"encoding/json"
 
 	"github.com/golang/protobuf/ptypes/empty"
 	"github.com/hashicorp/go-argmapper"
@@ -134,8 +135,17 @@ func (c *registryClient) push(
 		return nil, err
 	}
 
-	// We return the *any.Any directly.
-	return &plugincomponent.Artifact{Any: resp.Result}, nil
+	var tplData map[string]interface{}
+	if len(resp.TemplateData) > 0 {
+		if err := json.Unmarshal(resp.TemplateData, &tplData); err != nil {
+			return nil, err
+		}
+	}
+
+	return &plugincomponent.Artifact{
+		Any:         resp.Result,
+		TemplateVal: tplData,
+	}, nil
 }
 
 // registryServer is a gRPC server that the client talks to and calls a
@@ -190,7 +200,7 @@ func (s *registryServer) Push(
 	internal := s.internal()
 	defer internal.Cleanup.Close()
 
-	encoded, _, err := callDynamicFuncAny2(s.Impl.PushFunc(), args.Args,
+	encoded, raw, err := callDynamicFuncAny2(s.Impl.PushFunc(), args.Args,
 		argmapper.ConverterFunc(s.Mappers...),
 		argmapper.Logger(s.Logger),
 		argmapper.Typed(ctx),
@@ -200,7 +210,13 @@ func (s *registryServer) Push(
 		return nil, err
 	}
 
-	return &proto.Push_Resp{Result: encoded}, nil
+	result := &proto.Push_Resp{Result: encoded}
+	result.TemplateData, err = templateData(raw)
+	if err != nil {
+		return nil, err
+	}
+
+	return result, nil
 }
 
 var (

internal/plugin/releaser.go

@@ -2,6 +2,7 @@ package plugin
 
 import (
 	"context"
+	"encoding/json"
 
 	"github.com/golang/protobuf/ptypes/empty"
 	"github.com/hashicorp/go-argmapper"
@@ -181,10 +182,18 @@ func (c *releaseManagerClient) build(
 		return nil, err
 	}
 
+	var tplData map[string]interface{}
+	if len(resp.TemplateData) > 0 {
+		if err := json.Unmarshal(resp.TemplateData, &tplData); err != nil {
+			return nil, err
+		}
+	}
+
 	// We return the
 	return &plugincomponent.Release{
-		Any:     resp.Result,
-		Release: resp.Release,
+		Any:         resp.Result,
+		Release:     resp.Release,
+		TemplateVal: tplData,
 	}, nil
 }
 
@@ -257,12 +266,19 @@ func (s *releaseManagerServer) Release(
 	}
 
 	release := raw.(component.Release)
-	return &proto.Release_Resp{
+	result := &proto.Release_Resp{
 		Result: encoded,
 		Release: &proto.Release{
 			Url: release.URL(),
 		},
-	}, nil
+	}
+
+	result.TemplateData, err = templateData(raw)
+	if err != nil {
+		return nil, err
+	}
+
+	return result, nil
 }
 
 var (

internal/plugin/template.go

@@ -0,0 +1,88 @@
+package plugin
+
+import (
+	"encoding/json"
+	"reflect"
+	"strings"
+
+	"github.com/iancoleman/strcase"
+	"github.com/mitchellh/mapstructure"
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/status"
+
+	"github.com/hashicorp/waypoint-plugin-sdk/component"
+)
+
+// templateData returns the template data for a result object. If v
+// implements component.Template that value is used. Otherwise, we automatically
+// infer the fields based on the exported fields of the struct.
+func templateData(v interface{}) ([]byte, error) {
+	// Determine our data
+	var data map[string]interface{}
+	if tpl, ok := v.(component.Template); ok {
+		data = tpl.TemplateData()
+	} else {
+		data = templateDataFromConfig(v)
+	}
+
+	// If empty we don't do anything
+	if len(data) == 0 {
+		return nil, nil
+	}
+
+	// Encode as JSON
+	encoded, err := json.Marshal(data)
+	if err != nil {
+		return nil, status.Errorf(codes.Aborted,
+			"failed to JSON encode result template data: %s", err)
+	}
+
+	return encoded, nil
+}
+
+func templateDataFromConfig(v interface{}) map[string]interface{} {
+	var result map[string]interface{}
+	dec, err := mapstructure.NewDecoder(&mapstructure.DecoderConfig{
+		Result: &result,
+		DecodeHook: func(srcT, dstT reflect.Type, raw interface{}) (interface{}, error) {
+			for srcT.Kind() == reflect.Ptr {
+				srcT = srcT.Elem()
+			}
+			if srcT.Kind() != reflect.Struct {
+				return raw, nil
+			}
+
+			val := reflect.ValueOf(raw)
+			for val.Kind() == reflect.Ptr {
+				val = val.Elem()
+			}
+
+			m := map[string]interface{}{}
+			for i := 0; i < srcT.NumField(); i++ {
+				sf := srcT.Field(i)
+				if sf.PkgPath != "" {
+					// ignore unexported fields
+					continue
+				}
+
+				if strings.HasPrefix(sf.Name, "XXX_") {
+					// ignore proto internals
+					continue
+				}
+
+				name := strcase.ToSnake(sf.Name)
+				m[name] = val.Field(i).Interface()
+			}
+
+			return m, nil
+		},
+	})
+	if err != nil {
+		panic(err)
+	}
+	if err := dec.Decode(v); err != nil {
+		panic(err)
+	}
+
+	return result
+}

internal/plugin/template_test.go

@@ -0,0 +1,71 @@
+package plugin
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestTemplateDataFromConfig(t *testing.T) {
+	cases := []struct {
+		Name   string
+		Input  interface{}
+		Output map[string]interface{}
+	}{
+		{
+			"all-in-one",
+			struct {
+				Name      string
+				Port      int
+				ImageName string
+			}{
+				Name:      "Hello",
+				Port:      80,
+				ImageName: "foo",
+			},
+			map[string]interface{}{
+				"name":       "Hello",
+				"port":       80,
+				"image_name": "foo",
+			},
+		},
+
+		{
+			"pointer",
+			&struct {
+				Name string
+				Port int
+			}{
+				Name: "Hello",
+				Port: 80,
+			},
+			map[string]interface{}{
+				"name": "Hello",
+				"port": 80,
+			},
+		},
+
+		{
+			"protobuf fields",
+			&struct {
+				Name      string
+				XXX_Hello string
+			}{
+				Name:      "Hello",
+				XXX_Hello: "hi",
+			},
+			map[string]interface{}{
+				"name": "Hello",
+			},
+		},
+	}
+
+	for _, tt := range cases {
+		t.Run(tt.Name, func(t *testing.T) {
+			require := require.New(t)
+
+			v := templateDataFromConfig(tt.Input)
+			require.Equal(tt.Output, v)
+		})
+	}
+}