feat: improve sdk to use generic struct (#193)

Author: RobertIndie

clients/gofs/api.go

@@ -0,0 +1,156 @@
+/*
+ * Copyright 2024 DefFunction Stream Org.
+ *
+ * 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 gofs
+
+import "context"
+
+type FunctionContext interface {
+	context.Context
+	GetState(ctx context.Context, key string) ([]byte, error)
+	PutState(ctx context.Context, key string, value []byte) error
+	Write(ctx context.Context, rawEvent Event[[]byte]) error
+	Read(ctx context.Context) (Event[[]byte], error)
+	GetConfig(ctx context.Context) (map[string]string, error)
+}
+
+type Event[T any] interface {
+	Data() *T
+	Ack(ctx context.Context) error
+}
+
+type BaseModule interface {
+	Init(ctx FunctionContext) error
+}
+
+type Function[I any, O any] interface {
+	BaseModule
+	Handle(ctx FunctionContext, event Event[I]) (Event[O], error)
+}
+
+type Source[O any] interface {
+	BaseModule
+	Handle(ctx FunctionContext, emit func(context.Context, Event[O]) error) error
+}
+
+type Sink[I any] interface {
+	BaseModule
+	Handle(ctx FunctionContext, event Event[I]) error
+}
+
+type Custom interface {
+	BaseModule
+	Handle(ctx FunctionContext) error
+}
+
+type eventImpl[T any] struct {
+	data    *T
+	ackFunc func(context.Context) error
+}
+
+func NewEvent[T any](data *T) Event[T] {
+	return NewEventWithAck(data, nil)
+}
+
+func NewEventWithAck[T any](data *T, ack func(ctx context.Context) error) Event[T] {
+	return &eventImpl[T]{
+		data:    data,
+		ackFunc: ack,
+	}
+}
+
+func (e *eventImpl[T]) Data() *T {
+	return e.data
+}
+
+func (e *eventImpl[T]) Ack(ctx context.Context) error {
+	if e.ackFunc != nil {
+		return e.ackFunc(ctx)
+	}
+	return nil
+}
+
+type simpleFunction[I any, O any] struct {
+	handle func(ctx FunctionContext, event Event[I]) (Event[O], error)
+}
+
+func NewSimpleFunction[I any, O any](handle func(ctx FunctionContext, event Event[I]) (Event[O], error)) Function[I, O] {
+	return &simpleFunction[I, O]{
+		handle: handle,
+	}
+}
+
+func (f *simpleFunction[I, O]) Init(_ FunctionContext) error {
+	return nil
+}
+
+func (f *simpleFunction[I, O]) Handle(ctx FunctionContext, event Event[I]) (Event[O], error) {
+	return f.handle(ctx, event)
+}
+
+type simpleSource[O any] struct {
+	handle func(ctx FunctionContext, emit func(context.Context, Event[O]) error) error
+}
+
+func NewSimpleSource[O any](handle func(ctx FunctionContext, emit func(context.Context, Event[O]) error) error) Source[O] {
+	return &simpleSource[O]{
+		handle: handle,
+	}
+}
+
+func (s *simpleSource[O]) Init(_ FunctionContext) error {
+	return nil
+}
+
+func (s *simpleSource[O]) Handle(ctx FunctionContext, emit func(context.Context, Event[O]) error) error {
+	return s.handle(ctx, emit)
+}
+
+type simpleSink[I any] struct {
+	handle func(ctx FunctionContext, event Event[I]) error
+}
+
+func NewSimpleSink[I any](handle func(ctx FunctionContext, event Event[I]) error) Sink[I] {
+	return &simpleSink[I]{
+		handle: handle,
+	}
+}
+
+func (s *simpleSink[I]) Init(_ FunctionContext) error {
+	return nil
+}
+
+func (s *simpleSink[I]) Handle(ctx FunctionContext, event Event[I]) error {
+	return s.handle(ctx, event)
+}
+
+type simpleCustom struct {
+	handle func(ctx FunctionContext) error
+}
+
+func NewSimpleCustom(handle func(ctx FunctionContext) error) Custom {
+	return &simpleCustom{
+		handle: handle,
+	}
+}
+
+func (c *simpleCustom) Init(_ FunctionContext) error {
+	return nil
+}
+
+func (c *simpleCustom) Handle(ctx FunctionContext) error {
+	return c.handle(ctx)
+}