provide required schema for basic template and fbc conversion

alpha/declcfg/declcfg.go

@@ -70,8 +70,8 @@ type ChannelEntry struct {
 //     evaluation in bundlesEqual().
 type Bundle struct {
 	Schema        string              `json:"schema"`
-	Name          string              `json:"name"`
-	Package       string              `json:"package"`
+	Name          string              `json:"name,omitempty"`
+	Package       string              `json:"package,omitempty"`
 	Image         string              `json:"image"`
 	Properties    []property.Property `json:"properties,omitempty" hash:"set"`
 	RelatedImages []RelatedImage      `json:"relatedImages,omitempty" hash:"set"`

alpha/declcfg/load.go

@@ -259,6 +259,17 @@ func LoadFile(root fs.FS, path string) (*DeclarativeConfig, error) {
 	return cfg, nil
 }
 
+// LoadSlice will compose declarative config components from a slice of Meta objects
+func LoadSlice(metas []*Meta) (*DeclarativeConfig, error) {
+	builder := fbcBuilder{}
+	for _, meta := range metas {
+		if err := builder.addMeta(meta); err != nil {
+			return nil, err
+		}
+	}
+	return &builder.cfg, nil
+}
+
 type fbcBuilder struct {
 	cfg DeclarativeConfig
 

alpha/template/basic/basic.go

@@ -2,25 +2,58 @@ package basic
 
 import (
 	"context"
+	"encoding/json"
 	"fmt"
 	"io"
 
 	"github.com/operator-framework/operator-registry/alpha/action"
 	"github.com/operator-framework/operator-registry/alpha/declcfg"
 	"github.com/operator-framework/operator-registry/pkg/image"
+	"k8s.io/apimachinery/pkg/util/yaml"
 )
 
+const schema string = "olm.template.basic"
+
 type Template struct {
 	Registry image.Registry
 }
 
+type BasicTemplate struct {
+	Schema  string          `json:"schema"`
+	Entries []*declcfg.Meta `json:"entries"`
+}
+
+func parseSpec(reader io.Reader) (*BasicTemplate, error) {
+	bt := &BasicTemplate{}
+	btDoc := json.RawMessage{}
+	btDecoder := yaml.NewYAMLOrJSONDecoder(reader, 4096)
+	err := btDecoder.Decode(&btDoc)
+	if err != nil {
+		return nil, fmt.Errorf("decoding template schema: %v", err)
+	}
+	err = json.Unmarshal(btDoc, bt)
+	if err != nil {
+		return nil, fmt.Errorf("unmarshalling template: %v", err)
+	}
+
+	if bt.Schema != schema {
+		return nil, fmt.Errorf("template has unknown schema (%q), should be %q", bt.Schema, schema)
+	}
+
+	return bt, nil
+}
+
 func (t Template) Render(ctx context.Context, reader io.Reader) (*declcfg.DeclarativeConfig, error) {
-	cfg, err := declcfg.LoadReader(reader)
+	bt, err := parseSpec(reader)
+	if err != nil {
+		return nil, err
+	}
+	cfg, err := declcfg.LoadSlice(bt.Entries)
 	if err != nil {
 		return cfg, err
 	}
 
-	outb := cfg.Bundles[:0] // allocate based on max size of input, but empty slice
+	outb := cfg.Bundles[:0]
 	// populate registry, incl any flags from CLI, and enforce only rendering bundle images
 	r := action.Render{
 		Registry:       t.Registry,
@@ -48,3 +81,38 @@ func (t Template) Render(ctx context.Context, reader io.Reader) (*declcfg.Declar
 func isBundleTemplate(b *declcfg.Bundle) bool {
 	return b.Schema != "" && b.Image != "" && b.Package == "" && len(b.Properties) == 0 && len(b.RelatedImages) == 0
 }
+
+// FromReader reads FBC from a reader and generates a BasicTemplate from it
+func FromReader(r io.Reader) (*BasicTemplate, error) {
+	var entries []*declcfg.Meta
+	if err := declcfg.WalkMetasReader(r, func(meta *declcfg.Meta, err error) error {
+		if err != nil {
+			return err
+		}
+		if meta.Schema == declcfg.SchemaBundle {
+			var b declcfg.Bundle
+			if err := json.Unmarshal(meta.Blob, &b); err != nil {
+				return fmt.Errorf("parse bundle: %v", err)
+			}
+			b2 := declcfg.Bundle{
+				Schema: b.Schema,
+				Image:  b.Image,
+			}
+			meta.Blob, err = json.Marshal(b2)
+			if err != nil {
+				return fmt.Errorf("re-serialize bundle: %v", err)
+			}
+		}
+		entries = append(entries, meta)
+		return nil
+	}); err != nil {
+		return nil, err
+	}
+
+	bt := &BasicTemplate{
+		Schema:  schema,
+		Entries: entries,
+	}
+
+	return bt, nil
+}

alpha/template/converter/converter.go

@@ -0,0 +1,39 @@
+package converter
+
+import (
+	"encoding/json"
+	"fmt"
+	"io"
+	"os"
+
+	"github.com/operator-framework/operator-registry/alpha/template/basic"
+	"github.com/operator-framework/operator-registry/pkg/image"
+	"sigs.k8s.io/yaml"
+)
+
+type Converter struct {
+	FbcReader    io.Reader
+	OutputFormat string
+	Registry     image.Registry
+}
+
+func (c *Converter) Convert() error {
+	bt, err := basic.FromReader(c.FbcReader)
+	if err != nil {
+		return err
+	}
+
+	b, _ := json.MarshalIndent(bt, "", "    ")
+	if c.OutputFormat == "json" {
+		fmt.Fprintln(os.Stdout, string(b))
+	} else {
+		y, err := yaml.JSONToYAML(b)
+		if err != nil {
+			return err
+		}
+		y = append([]byte("---\n"), y...)
+		fmt.Fprintln(os.Stdout, string(y))
+	}
+
+	return nil
+}

cmd/opm/alpha/cmd.go

@@ -4,6 +4,7 @@ import (
 	"github.com/spf13/cobra"
 
 	"github.com/operator-framework/operator-registry/cmd/opm/alpha/bundle"
+	converttemplate "github.com/operator-framework/operator-registry/cmd/opm/alpha/convert-template"
 	"github.com/operator-framework/operator-registry/cmd/opm/alpha/list"
 	rendergraph "github.com/operator-framework/operator-registry/cmd/opm/alpha/render-graph"
 	"github.com/operator-framework/operator-registry/cmd/opm/alpha/template"
@@ -26,6 +27,7 @@ func NewCmd(showAlphaHelp bool) *cobra.Command {
 		list.NewCmd(),
 		rendergraph.NewCmd(),
 		template.NewCmd(),
+		converttemplate.NewCmd(),
 	)
 	return runCmd
 }

cmd/opm/alpha/convert-template/convert.go

@@ -0,0 +1,66 @@
+package converttemplate
+
+import (
+	"fmt"
+	"log"
+
+	"github.com/spf13/cobra"
+
+	"github.com/operator-framework/operator-registry/alpha/template/converter"
+	"github.com/operator-framework/operator-registry/cmd/opm/internal/util"
+)
+
+func NewCmd() *cobra.Command {
+	cmd := &cobra.Command{
+		Use:   "convert-template",
+		Short: "Convert existing FBC to a supported template type",
+	}
+	cmd.AddCommand(
+		newBasicConvertCmd(),
+	)
+	return cmd
+}
+
+func newBasicConvertCmd() *cobra.Command {
+	var (
+		converter converter.Converter
+		output    string
+	)
+	cmd := &cobra.Command{
+		Use:   "basic [<fbc-file> | -]",
+		Args:  cobra.MaximumNArgs(1),
+		Short: "Generate a basic template from existing FBC",
+		Long: `Generate a basic template from existing FBC.
+
+This command outputs a basic catalog template to STDOUT from input FBC.
+If no argument is specified or is '-' input is assumed from STDIN.
+`,
+		RunE: func(c *cobra.Command, args []string) error {
+
+			switch output {
+			case "yaml":
+				fallthrough
+			case "json":
+				converter.OutputFormat = output
+			default:
+				log.Fatalf("invalid --output value %q, expected (json|yaml)", output)
+			}
+
+			reader, name, err := util.OpenFileOrStdin(c, args)
+			if err != nil {
+				return fmt.Errorf("unable to open input: %q", name)
+			}
+
+			converter.FbcReader = reader
+			err = converter.Convert()
+			if err != nil {
+				return fmt.Errorf("converting: %v", err)
+			}
+
+			return nil
+		},
+	}
+	cmd.Flags().StringVarP(&output, "output", "o", "json", "Output format (json|yaml)")
+
+	return cmd
+}

cmd/opm/alpha/template/basic.go

@@ -16,7 +16,6 @@ import (
 func newBasicTemplateCmd() *cobra.Command {
 	var (
 		template basic.Template
-		output   string
 	)
 	cmd := &cobra.Command{
 		Use: "basic basic-template-file",
@@ -30,13 +29,17 @@ When FILE is '-' or not provided, the template is read from standard input`,
 			// When no arguments or "-" is passed to the command,
 			// assume input is coming from stdin
 			// Otherwise open the file passed to the command
-			data, source, err := openFileOrStdin(cmd, args)
+			data, source, err := util.OpenFileOrStdin(cmd, args)
 			if err != nil {
 				log.Fatalf("unable to open %q: %v", source, err)
 			}
 			defer data.Close()
 
 			var write func(declcfg.DeclarativeConfig, io.Writer) error
+			output, err := cmd.Flags().GetString("output")
+			if err != nil {
+				log.Fatalf("unable to determine output format")
+			}
 			switch output {
 			case "yaml":
 				write = declcfg.WriteYAML
@@ -70,6 +73,5 @@ When FILE is '-' or not provided, the template is read from standard input`,
 			}
 		},
 	}
-	cmd.Flags().StringVarP(&output, "output", "o", "json", "Output format (json|yaml)")
 	return cmd
 }

cmd/opm/alpha/template/cmd.go

@@ -1,29 +1,27 @@
 package template
 
 import (
-	"io"
-	"os"
-
 	"github.com/spf13/cobra"
 )
 
 func NewCmd() *cobra.Command {
+	var output string
+
 	runCmd := &cobra.Command{
 		Use:   "render-template",
 		Short: "Render a catalog template type",
 		Args:  cobra.NoArgs,
 	}
 
-	runCmd.AddCommand(newBasicTemplateCmd())
-	runCmd.AddCommand(newSemverTemplateCmd())
+	bc := newBasicTemplateCmd()
+	// bc.Hidden = true
+	runCmd.AddCommand(bc)
 
-	return runCmd
-}
+	sc := newSemverTemplateCmd()
+	// sc.Hidden = true
+	runCmd.AddCommand(sc)
 
-func openFileOrStdin(cmd *cobra.Command, args []string) (io.ReadCloser, string, error) {
-	if len(args) == 0 || args[0] == "-" {
-		return io.NopCloser(cmd.InOrStdin()), "stdin", nil
-	}
-	reader, err := os.Open(args[0])
-	return reader, args[0], err
+	runCmd.PersistentFlags().StringVarP(&output, "output", "o", "json", "Output format (json|yaml)")
+
+	return runCmd
 }

cmd/opm/alpha/template/semver.go

@@ -15,7 +15,6 @@ import (
 )
 
 func newSemverTemplateCmd() *cobra.Command {
-	output := ""
 	cmd := &cobra.Command{
 		Use: "semver [FILE]",
 		Short: `Generate a file-based catalog from a single 'semver template' file
@@ -28,13 +27,17 @@ When FILE is '-' or not provided, the template is read from standard input`,
 			// When no arguments or "-" is passed to the command,
 			// assume input is coming from stdin
 			// Otherwise open the file passed to the command
-			data, source, err := openFileOrStdin(cmd, args)
+			data, source, err := util.OpenFileOrStdin(cmd, args)
 			if err != nil {
 				return err
 			}
 			defer data.Close()
 
 			var write func(declcfg.DeclarativeConfig, io.Writer) error
+			output, err := cmd.Flags().GetString("output")
+			if err != nil {
+				log.Fatalf("unable to determine output format")
+			}
 			switch output {
 			case "json":
 				write = declcfg.WriteJSON
@@ -79,6 +82,5 @@ When FILE is '-' or not provided, the template is read from standard input`,
 		},
 	}
 
-	cmd.Flags().StringVarP(&output, "output", "o", "json", "Output format (json|yaml|mermaid)")
 	return cmd
 }

cmd/opm/internal/util/util.go

@@ -2,6 +2,7 @@ package util
 
 import (
 	"errors"
+	"io"
 	"os"
 
 	"github.com/spf13/cobra"
@@ -66,3 +67,11 @@ func CreateCLIRegistry(cmd *cobra.Command) (*containerdregistry.Registry, error)
 	}
 	return reg, nil
 }
+
+func OpenFileOrStdin(cmd *cobra.Command, args []string) (io.ReadCloser, string, error) {
+	if len(args) == 0 || args[0] == "-" {
+		return io.NopCloser(cmd.InOrStdin()), "stdin", nil
+	}
+	reader, err := os.Open(args[0])
+	return reader, args[0], err
+}