feat: NewMethodNameFormatter concept

Author: chris-4chain

README.md

@@ -250,10 +250,11 @@ if err := client.Call(); err != nil {
 
 `WithServerMethodNameFormatter` allows you to customize a function that formats the JSON-RPC method name, given namespace and method name.
 
-There are three predefined formatters:
+There are four predefined options:
 - `jsonrpc.DefaultMethodNameFormatter` - default method name formatter, e.g. `SimpleServerHandler.AddGet`
-- `jsonrpc.NoNamespaceMethodNameFormatter` - method name formatter without namespace, e.g. `AddGet`
-- `jsonrpc.NoNamespaceDecapitalizedMethodNameFormatter` - method name formatter without namespace and decapitalized, e.g. `addGet`
+- `jsonrpc.NewMethodNameFormatter(true, jsonrpc.LowerFirstCharCase)` - method name formatter with namespace, e.g. `SimpleServerHandler.addGet`
+- `jsonrpc.NewMethodNameFormatter(false, jsonrpc.OriginalCase)` - method name formatter without namespace, e.g. `AddGet`
+- `jsonrpc.NewMethodNameFormatter(false, jsonrpc.LowerFirstCharCase)` - method name formatter without namespace and with the first char lowercased, e.g. `addGet`
 
 > [!NOTE]  
 > The default method name formatter concatenates the namespace and method name with a dot.
@@ -297,7 +298,7 @@ func main() {
         "SimpleServerHandler",
         []any{&client},
         nil,
-        WithMethodNameFormatter(test.namer),
+        WithMethodNameFormatter(jsonrpc.NewMethodNameFormatter(false, OriginalCase)),
     )
     defer closer()
 }

method_formatter.go

@@ -6,21 +6,27 @@ import "strings"
 // This is useful if you want to customize the default behaviour, e.g. send without the namespace or make it lowercase.
 type MethodNameFormatter func(namespace, method string) string
 
-// DefaultMethodNameFormatter joins the namespace and method name with a dot.
-func DefaultMethodNameFormatter(namespace, method string) string {
-	return namespace + "." + method
-}
+// CaseStyle represents the case style for method names.
+type CaseStyle int
 
-// NoNamespaceMethodNameFormatter returns the method name as is, without the namespace.
-func NoNamespaceMethodNameFormatter(_, method string) string {
-	return method
-}
+const (
+	OriginalCase CaseStyle = iota
+	LowerFirstCharCase
+)
 
-// NoNamespaceDecapitalizedMethodNameFormatter returns the method name as is, without the namespace, and decapitalizes the first letter.
-// e.g. "Inc" -> "inc"
-func NoNamespaceDecapitalizedMethodNameFormatter(_, method string) string {
-	if len(method) == 0 {
-		return ""
+// NewMethodNameFormatter creates a new method name formatter based on the provided options.
+func NewMethodNameFormatter(includeNamespace bool, nameCase CaseStyle) MethodNameFormatter {
+	return func(namespace, method string) string {
+		formattedMethod := method
+		if nameCase == LowerFirstCharCase && len(method) > 0 {
+			formattedMethod = strings.ToLower(method[:1]) + method[1:]
+		}
+		if includeNamespace {
+			return namespace + "." + formattedMethod
+		}
+		return formattedMethod
 	}
-	return strings.ToLower(method[:1]) + method[1:]
 }
+
+// DefaultMethodNameFormatter is a pass-through formatter with default options.
+var DefaultMethodNameFormatter = NewMethodNameFormatter(true, OriginalCase)

method_formatter_test.go

@@ -20,12 +20,16 @@ func TestDifferentMethodNamers(t *testing.T) {
 			namer:           DefaultMethodNameFormatter,
 			requestedMethod: "SimpleServerHandler.Inc",
 		},
+		"lower fist char": {
+			namer:           NewMethodNameFormatter(true, LowerFirstCharCase),
+			requestedMethod: "SimpleServerHandler.inc",
+		},
 		"no namespace namer": {
-			namer:           NoNamespaceMethodNameFormatter,
+			namer:           NewMethodNameFormatter(false, OriginalCase),
 			requestedMethod: "Inc",
 		},
-		"no namespace & decapitalized namer": {
-			namer:           NoNamespaceDecapitalizedMethodNameFormatter,
+		"no namespace & lower fist char": {
+			namer:           NewMethodNameFormatter(false, LowerFirstCharCase),
 			requestedMethod: "inc",
 		},
 	}
@@ -63,20 +67,28 @@ func TestDifferentMethodNamersWithClient(t *testing.T) {
 			namer:     DefaultMethodNameFormatter,
 			urlPrefix: "ws://",
 		},
+		"lower first char namer & http": {
+			namer:     NewMethodNameFormatter(true, LowerFirstCharCase),
+			urlPrefix: "http://",
+		},
+		"lower first char namer & ws": {
+			namer:     NewMethodNameFormatter(true, LowerFirstCharCase),
+			urlPrefix: "ws://",
+		},
 		"no namespace namer & http": {
-			namer:     NoNamespaceMethodNameFormatter,
+			namer:     NewMethodNameFormatter(false, OriginalCase),
 			urlPrefix: "http://",
 		},
 		"no namespace namer & ws": {
-			namer:     NoNamespaceMethodNameFormatter,
+			namer:     NewMethodNameFormatter(false, OriginalCase),
 			urlPrefix: "ws://",
 		},
-		"no namespace & decapitalized namer & http": {
-			namer:     NoNamespaceDecapitalizedMethodNameFormatter,
+		"no namespace & lower first char & http": {
+			namer:     NewMethodNameFormatter(false, LowerFirstCharCase),
 			urlPrefix: "http://",
 		},
-		"no namespace & decapitalized namer & ws": {
-			namer:     NoNamespaceDecapitalizedMethodNameFormatter,
+		"no namespace & lower first char & ws": {
+			namer:     NewMethodNameFormatter(false, LowerFirstCharCase),
 			urlPrefix: "ws://",
 		},
 	}