First version of crd generator

cmd/codegen/main.go

@@ -0,0 +1,79 @@
+/*
+Copyright 2020 The Kubermatic Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package main
+
+import (
+	"fmt"
+	"os"
+
+	"github.com/spf13/cobra"
+
+	"github.com/kubermatic/utils/pkg/codegen/scaffold"
+)
+
+func main() {
+	opts := &scaffold.ScaffoldOptions{
+		Resource: scaffold.Resource{
+			Version: "v1alpha1",
+		},
+		Spec: scaffold.Spec{
+			Metadata: true,
+		},
+		Boilerplate: "./hack/boilerplate/boilerplate.go.txt",
+	}
+	scaffoldCmd := &cobra.Command{
+		Use:   "crdgen",
+		Short: "Quickly scaffold out basic bits of a Kubernetes type.",
+		Long: `Quickly scaffold out the structure of a type for a Kubernetes kind and associated types.
+Produces:
+
+- a root type with appropriate metadata fields
+- Spec and Status types
+- a list type
+
+Also applies the appropriate comments to generate the code required to conform to runtime.Object.`,
+		Example: `	# Generate types for a Kind called Foo with a resource called foos
+		crdgen --kind Foo
+
+	# Generate types for a Kind called Bar with metadata in its Spec
+	crdgen --kind Bar --metadata`,
+		RunE: func(_ *cobra.Command, _ []string) error {
+			if err := opts.Validate(); err != nil {
+				return err
+			}
+			return opts.Scaffold()
+		},
+	}
+
+	scaffoldCmd.Flags().StringVar(&opts.OutputPath, "output", opts.OutputPath, "the Path of the generated file, for example foo_types.go")
+	scaffoldCmd.Flags().StringVar(&opts.Resource.Kind, "kind", opts.Resource.Kind, "The Kind of the typescaffold being scaffolded.")
+	scaffoldCmd.Flags().StringVar(&opts.Resource.Version, "version", opts.Resource.Version, "The Version of the typescaffold being scaffolded.")
+	scaffoldCmd.Flags().StringVar(&opts.Boilerplate, "boilerplate", opts.Boilerplate, "The Boilerplate header file path.")
+	scaffoldCmd.Flags().BoolVar(&opts.Spec.Metadata, "metadata", opts.Spec.Metadata, "Whether wants to generate metadata fields in the Spec of this Kind")
+
+	if err := cobra.MarkFlagRequired(scaffoldCmd.Flags(), "kind"); err != nil {
+		panic("unable to mark --kind as required")
+	}
+
+	if err := scaffoldCmd.Execute(); err != nil {
+		if _, err := fmt.Fprintln(os.Stderr, err); err != nil {
+			// this would be exceedingly bizarre if we ever got here
+			panic("unable to write to error details to standard error")
+		}
+		os.Exit(1)
+	}
+}

pkg/codegen/scaffold/resource.go

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+/*
+Copyright 2020 The Kubermatic Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package scaffold
+
+import (
+	"fmt"
+)
+
+// Resource contains the information required to scaffold files for a resource.
+type Resource struct {
+	// Kind is the API Kind.
+	Kind string
+	// Version is the API Version.
+	Version string
+}
+
+// Validate checks the Resource values to make sure they are valid.
+func (r *Resource) Validate() error {
+	if len(r.Kind) == 0 {
+		return fmt.Errorf("kind cannot be empty")
+	}
+	return nil
+}