Update interfaces

README.md

@@ -14,7 +14,49 @@ var request protocol.InitializeRequest
 
 All lsprotocol types are in the `protocol` package.
 
-## TODO
-- Currently only types are provided. Would be nice to also provide utility functions for creating a request/response.
-- the microsoft tests only test for proper unmarshalling. probably should add tests to make sure structs marshal correctly as well.
-- I'm not a golang expert. There may be more efficient ways to do things like validation or tagged unions.
+## Utilities
+This package provides a limited number of utility functions for dealing with jsonrpc messages.
+
+**DecodeMessage**
+This is a helper that takes in a full jsonrpc message and returns a message object.
+
+```golang
+var content = []byte("Content-Length: 20\r\n\r\n{...etc}")
+message, err := protocol.DecodeMessage(content)
+```
+
+**SplitMessage**
+This is a helper that takes in a full jsonrpc message and returns information about the message.
+
+```golang
+var content = []byte("Content-Length: 20\r\n\r\n{...etc}")
+messageLengthIncludingTheHeader, contentLength, content, err := protocol.SplitMessage(content)
+```
+
+**Split**
+This is a helper you can use with scanner to read jsonrpc messages from a stream.
+
+```golang
+var scanner = bufio.NewScanner(reader)
+scanner.Split(protocol.Split)
+for scanner.Scan() {
+	msg := scanner.Bytes()
+	// handle message
+}
+```
+
+**Error**
+This is a tiny helper that takes in an error coe and an `error` instance, and returns a `ResponseError`
+
+```golang
+responseError := protocol.Error(someErrorCode, err)
+```
+
+## Interfaces
+The following interfaces are provided by this package:
+
+- `Request` - represents a jsonrpc request
+- `Response` - represents a jsonrpc response
+- `Notification` - represents a jsonrpc notification
+- `Message` - represents a jsonrpc message
+- `IncomingMessage` - notification or request. not in the spec but super helpful.

lspgenerator/go/base_types.py

@@ -120,12 +120,17 @@ def generate_base_types(
 			],
 		),
 	)
+	result.append("type MethodKind string")
 	result.append(
 		join(
 			[
 				"type Message interface {",
 				"	isMessage()",
 				"}",
+				"type IncomingMessage interface {",
+				"	GetMethod() MethodKind",
+				"	GetParams() any",
+				"}",
 				"type Request interface {",
 				"	isRequest()",
 				"}",

lspgenerator/go/notifications.py

@@ -9,20 +9,18 @@ def generate_notifications(
 	type_resolver: TypeResolver,
 ) -> list[str]:
 	notifications = sorted(spec.notifications, key=lambda x: x.method)
-	result = [
-		"type NotificationMethod string\n",
-	]
+	result = []
 	constants = "const (\n"
-	constants += '\tUnknownNotificationMethod = ""\n'
+	constants += '\tUnknownNotificationMethod MethodKind = ""\n'
 
 	for notification in notifications:
 		method = notification.method.replace("$", "Optional")
 		camel_case_method = method_to_camel_case(method)
-		constants += f'\t{camel_case_method}Method NotificationMethod = "{notification.method}"\n'
+		constants += f'\t{camel_case_method}Method MethodKind = "{notification.method}"\n'
 	constants += ")\n"
 	result.append(constants)
 	result.append(
-		"var NotificationMethodMap = map[string]NotificationMethod{",
+		"var NotificationMethodMap = map[string]MethodKind{",
 	)
 	for notification in notifications:
 		method = notification.method.replace("$", "Optional")
@@ -42,14 +40,20 @@ def generate_notifications(
 			lines_to_comments(notification.documentation),
 			f"type {notification.typeName} struct {{",
 			'\tJsonRPC string `json:"jsonrpc"`',
-			'\tMethod string `json:"method"`',
+			'\tMethod MethodKind `json:"method"`',
 			f'\tParams {param_type} `json:"params"`',
 		]
 		struct.append("}")
 		struct.append(f"func (t {notification.typeName}) isMessage() {{}}")
 		struct.append(
 			f"func (t {notification.typeName}) isNotification() {{}}",
 		)
+		struct.append(
+			f"func (t {notification.typeName}) GetMethod() MethodKind {{ return t.Method }}",
+		)
+		struct.append(
+			f"func (t {notification.typeName}) GetParams() any {{ return t.Params }}",
+		)
 		struct += [
 			f"func (t *{notification.typeName}) UnmarshalJSON(x []byte) error {{",
 			"   var m map[string]any",

lspgenerator/go/requests.py

@@ -14,21 +14,19 @@ def generate_requests(
 ) -> list[str]:
 	requests = sorted(spec.requests, key=lambda x: x.method)
 
-	result = [
-		"type RequestMethod string\n",
-	]
+	result = []
 	constants = "const (\n"
-	constants += '\tUnknownRequestMethod RequestMethod = ""\n'
+	constants += '\tUnknownRequestMethod MethodKind = ""\n'
 
 	for request in requests:
 		camel_case_method = method_to_camel_case(request.method)
 		constants += (
-			f'\t{camel_case_method}Method RequestMethod = "{request.method}"\n'
+			f'\t{camel_case_method}Method MethodKind = "{request.method}"\n'
 		)
 	constants += ")\n"
 	result.append(constants)
 
-	result.append("var RequestMethodMap = map[string]RequestMethod{")
+	result.append("var RequestMethodMap = map[string]MethodKind{")
 	for request in requests:
 		camel_case_method = method_to_camel_case(request.method)
 		result.append(
@@ -45,13 +43,19 @@ def generate_requests(
 			f"type {request.typeName} struct {{",
 			'\tJsonRPC string `json:"jsonrpc"`',
 			'\tID Or2[string, int32] `json:"id"`',
-			'\tMethod RequestMethod `json:"method"`',
+			'\tMethod MethodKind `json:"method"`',
 			f'\tParams {param_type} `json:"params"`',
 		]
 
 		struct.append("}")
 		struct.append(f"func (t {request.typeName}) isMessage() {{}}")
 		struct.append(f"func (t {request.typeName}) isRequest() {{}}")
+		struct.append(
+			f"func (t {request.typeName}) GetMethod() MethodKind {{ return t.Method }}",
+		)
+		struct.append(
+			f"func (t {request.typeName}) GetParams() any {{ return t.Params }}",
+		)
 		struct += [
 			f"func (t *{request.typeName}) UnmarshalJSON(x []byte) error {{",
 			"   var m map[string]any",

protocol/interfaces_test.go

@@ -2,10 +2,12 @@ package protocol
 
 // Compile-time interface compliance checks
 var (
-	_ Message      = (*InitializeRequest)(nil)
-	_ Message      = (*InitializedNotification)(nil)
-	_ Message      = (*InitializeResponse)(nil)
-	_ Request      = (*InitializeRequest)(nil)
-	_ Notification = (*InitializedNotification)(nil)
-	_ Response     = (*InitializeResponse)(nil)
+	_ Message         = (*InitializeRequest)(nil)
+	_ Message         = (*InitializedNotification)(nil)
+	_ Message         = (*InitializeResponse)(nil)
+	_ Request         = (*InitializeRequest)(nil)
+	_ Notification    = (*InitializedNotification)(nil)
+	_ Response        = (*InitializeResponse)(nil)
+	_ IncomingMessage = (*InitializeRequest)(nil)
+	_ IncomingMessage = (*InitializedNotification)(nil)
 )