feat(decl/resources): add resource builder

Signed-off-by: Leonardo Di Giovanna <leonardodigiovanna1@gmail.com>
Co-authored-by: Aldo Lacuku <aldo@lacuku.eu>

pkg/test/resource/builder/builder.go

@@ -0,0 +1,138 @@
+// SPDX-License-Identifier: Apache-2.0
+// Copyright (C) 2024 The Falco 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 builder
+
+import (
+	"fmt"
+
+	"github.com/go-logr/logr"
+
+	"github.com/falcosecurity/event-generator/pkg/test/loader"
+	"github.com/falcosecurity/event-generator/pkg/test/resource"
+	"github.com/falcosecurity/event-generator/pkg/test/resource/clientserver"
+	"github.com/falcosecurity/event-generator/pkg/test/resource/fd/directory"
+	"github.com/falcosecurity/event-generator/pkg/test/resource/fd/epoll"
+	"github.com/falcosecurity/event-generator/pkg/test/resource/fd/event"
+	"github.com/falcosecurity/event-generator/pkg/test/resource/fd/file"
+	"github.com/falcosecurity/event-generator/pkg/test/resource/fd/inotify"
+	"github.com/falcosecurity/event-generator/pkg/test/resource/fd/mem"
+	"github.com/falcosecurity/event-generator/pkg/test/resource/fd/pipe"
+	"github.com/falcosecurity/event-generator/pkg/test/resource/fd/signal"
+)
+
+// builder is an implementation of resource.Builder.
+type builder struct{}
+
+// Verify that builder implements resource.Builder interface.
+var _ resource.Builder = (*builder)(nil)
+
+// New creates a new builder.
+func New() (resource.Builder, error) {
+	return &builder{}, nil
+}
+
+func (b *builder) Build(logger logr.Logger, testResource *loader.TestResource) (resource.Resource, error) {
+	resourceType := testResource.Type
+	resourceName := testResource.Name
+	logger = logger.WithValues("resourceType", resourceType, "resourceName", resourceName)
+	switch resourceType {
+	case loader.TestResourceTypeClientServer:
+		clientServerSpec, ok := testResource.Spec.(*loader.TestResourceClientServerSpec)
+		if !ok {
+			return nil, fmt.Errorf("cannot parse clientServer spec")
+		}
+
+		// TODO: remove the cast and use a dedicated type for l4Proto
+		res := clientserver.New(logger, resourceName, string(clientServerSpec.L4Proto), clientServerSpec.Address)
+		return res, nil
+	case loader.TestResourceTypeFD:
+		fdSpec, ok := testResource.Spec.(*loader.TestResourceFDSpec)
+		if !ok {
+			return nil, fmt.Errorf("cannot parse fd spec")
+		}
+
+		res, err := b.buildFD(logger, resourceName, fdSpec)
+		if err != nil {
+			return nil, fmt.Errorf("cannot build fd resource: %w", err)
+		}
+
+		return res, nil
+	default:
+		return nil, fmt.Errorf("unknown test resource type %q", resourceType)
+	}
+}
+
+// buildFD builds a fd test resource.
+func (b *builder) buildFD(logger logr.Logger, resourceName string,
+	fdSpec *loader.TestResourceFDSpec) (resource.Resource, error) {
+	subtype := fdSpec.Subtype
+	logger = logger.WithValues("resourceSubtype", subtype)
+	switch subtype {
+	case loader.TestResourceFDSubtypeFile:
+		subSpec, ok := fdSpec.Spec.(*loader.TestResourceFDFileSpec)
+		if !ok {
+			return nil, fmt.Errorf("cannot parse file spec")
+		}
+
+		return file.New(logger, resourceName, subSpec.FilePath), nil
+	case loader.TestResourceFDSubtypeDirectory:
+		subSpec, ok := fdSpec.Spec.(*loader.TestResourceFDDirectorySpec)
+		if !ok {
+			return nil, fmt.Errorf("cannot parse directory spec")
+		}
+
+		return directory.New(logger, resourceName, subSpec.DirPath), nil
+	case loader.TestResourceFDSubtypePipe:
+		if _, ok := fdSpec.Spec.(*loader.TestResourceFDPipeSpec); !ok {
+			return nil, fmt.Errorf("cannot parse pipe spec")
+		}
+
+		return pipe.New(logger, resourceName), nil
+	case loader.TestResourceFDSubtypeEvent:
+		if _, ok := fdSpec.Spec.(*loader.TestResourceFDEventSpec); !ok {
+			return nil, fmt.Errorf("cannot parse event spec")
+		}
+
+		return event.New(logger, resourceName), nil
+	case loader.TestResourceFDSubtypeSignal:
+		if _, ok := fdSpec.Spec.(*loader.TestResourceFDSignalSpec); !ok {
+			return nil, fmt.Errorf("cannot parse signalfd spec")
+		}
+
+		return signal.New(logger, resourceName), nil
+	case loader.TestResourceFDSubtypeEpoll:
+		if _, ok := fdSpec.Spec.(*loader.TestResourceFDEpollSpec); !ok {
+			return nil, fmt.Errorf("cannot parse eventpoll spec")
+		}
+
+		return epoll.New(logger, resourceName), nil
+	case loader.TestResourceFDSubtypeInotify:
+		if _, ok := fdSpec.Spec.(*loader.TestResourceFDInotifySpec); !ok {
+			return nil, fmt.Errorf("cannot parse inotify spec")
+		}
+
+		return inotify.New(logger, resourceName), nil
+	case loader.TestResourceFDSubtypeMem:
+		subSpec, ok := fdSpec.Spec.(*loader.TestResourceFDMemSpec)
+		if !ok {
+			return nil, fmt.Errorf("cannot parse memfd spec")
+		}
+
+		return mem.New(logger, resourceName, subSpec.FileName), nil
+	default:
+		return nil, fmt.Errorf("unknown fd test resource subtype %q", subtype)
+	}
+}

pkg/test/resource/builder/doc.go

@@ -0,0 +1,17 @@
+// SPDX-License-Identifier: Apache-2.0
+// Copyright (C) 2024 The Falco 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 builder provides an implementation of resource.Builder.
+package builder

pkg/test/resource/resource.go

@@ -18,6 +18,8 @@ package resource
 import (
 	"context"
 
+	"github.com/go-logr/logr"
+
 	"github.com/falcosecurity/event-generator/pkg/test/field"
 	"github.com/falcosecurity/event-generator/pkg/test/loader"
 )
@@ -37,5 +39,5 @@ type Resource interface {
 type Builder interface {
 	// Build builds a new test resource.
 	// TODO: replace loader.TestResource with a dedicated type.
-	Build(testResource *loader.TestResource) (Resource, error)
+	Build(logger logr.Logger, testResource *loader.TestResource) (Resource, error)
 }