refactor: split setup logic from service.go into setup.go

Author: angelofallars

service.go

@@ -1,16 +1,10 @@
 package payrex
 
-import (
-	"fmt"
-	"reflect"
-	"strings"
-)
-
 // serviceProvider is the interface that all Service types implement.
 type serviceProvider interface {
 	// setupClient sets up the service by supplying it with the [Client].
 	setupClient(*Client)
-	// setup sets up the service's other data.
+	// setup sets up the service's service-specific data.
 	setup()
 }
 
@@ -24,40 +18,5 @@ func (s *service[T]) setupClient(client *Client) {
 	s.client = client
 }
 
-// setupServices sets up the Service fields.
-func (c *Client) setupServices() {
-	// I use reflection here mainly just for convenience: whenever new services
-	// are added I can just add them as a field to Client and I don't have to do anything else.
-	v := reflect.ValueOf(c).Elem()
-	for _, fieldName := range serviceFieldNames {
-		service := v.FieldByName(fieldName).Addr().Interface().(serviceProvider)
-
-		service.setupClient(c)
-		service.setup()
-	}
-}
-
-var serviceFieldNames []string = []string{}
-
-// init checks that all Service fields in the Client struct implement serviceProvider
-// and saves the service field names for later use.
-func init() {
-	v := reflect.ValueOf(&Client{}).Elem()
-
-	for _, field := range reflect.VisibleFields(v.Type()) {
-		if !field.IsExported() || !strings.HasPrefix(field.Type.Name(), "Service") {
-			continue
-		}
-
-		serviceField := v.FieldByName(field.Name).Addr().Interface()
-
-		if _, ok := serviceField.(serviceProvider); !ok {
-			panic(fmt.Sprintf(
-				"expected field 'Client.%s' of type '%s' to implement 'serviceProvider'",
-				field.Name, field.Type.Name(),
-			))
-		}
-
-		serviceFieldNames = append(serviceFieldNames, field.Name)
-	}
-}
+// Service types embedding service[T] will implement setup()
+// on their own to set up any service-specific configuration.

setup.go

@@ -0,0 +1,45 @@
+package payrex
+
+import (
+	"fmt"
+	"reflect"
+	"strings"
+)
+
+var serviceFieldNames []string = []string{}
+
+// setupServices sets up the Service fields.
+func (c *Client) setupServices() {
+	// I use reflection here mainly just for convenience: whenever new services
+	// are added I can just add them as a field to Client and I don't have to do anything else.
+	v := reflect.ValueOf(c).Elem()
+	for _, fieldName := range serviceFieldNames {
+		service := v.FieldByName(fieldName).Addr().Interface().(serviceProvider)
+
+		service.setupClient(c)
+		service.setup()
+	}
+}
+
+// init checks that all Service fields in the [Client] struct implement [serviceProvider],
+// and saves the service field names in [serviceFieldNames] for later use.
+func init() {
+	v := reflect.ValueOf(&Client{}).Elem()
+
+	for _, field := range reflect.VisibleFields(v.Type()) {
+		if !field.IsExported() || !strings.HasPrefix(field.Type.Name(), "Service") {
+			continue
+		}
+
+		serviceField := v.FieldByName(field.Name).Addr().Interface()
+
+		if _, ok := serviceField.(serviceProvider); !ok {
+			panic(fmt.Sprintf(
+				"expected field 'Client.%s' of type '%s' to implement 'serviceProvider'",
+				field.Name, field.Type.Name(),
+			))
+		}
+
+		serviceFieldNames = append(serviceFieldNames, field.Name)
+	}
+}