feat(server/v2): Add Swagger UI support for server/v2

server/v2/api/swagger/config.go

@@ -0,0 +1,27 @@
+package swagger
+
+import "github.com/cosmos/cosmos-sdk/server/v2/config"
+
+// Config represents Swagger configuration options
+type Config struct {
+    // Enable enables the Swagger UI endpoint
+    Enable bool `mapstructure:"enable"`
+    // Path is the URL path where Swagger UI will be served
+    Path string `mapstructure:"path"`
+}
+
+// DefaultConfig returns default configuration for Swagger
+func DefaultConfig() Config {
+    return Config{
+        Enable: false,
+        Path:   "/swagger",
+    }
+}
+
+// Validate validates the configuration
+func (c Config) Validate() error {
+    if c.Path == "" {
+        return fmt.Errorf("swagger path cannot be empty")
+    }
+    return nil
+} 

server/v2/api/swagger/handler.go

@@ -0,0 +1,46 @@
+package swagger
+
+import (
+    "net/http"
+    "path"
+    "path/filepath"
+    "strings"
+
+    "github.com/rakyll/statik/fs"
+)
+
+// Handler returns an HTTP handler that serves the Swagger UI files
+func Handler(statikFS http.FileSystem) http.HandlerFunc {
+    return func(w http.ResponseWriter, r *http.Request) {
+        // If the path is empty or "/", show index.html
+        if r.URL.Path == "/" || r.URL.Path == "" {
+            r.URL.Path = "/index.html"
+        }
+
+        // Clearing the path
+        urlPath := path.Clean(r.URL.Path)
+
+        // Opening the file from statikFS
+        f, err := statikFS.Open(urlPath)
+        if err != nil {
+            w.WriteHeader(http.StatusNotFound)
+            return
+        }
+        defer f.Close()
+
+        // Determining the content-type
+        ext := strings.ToLower(filepath.Ext(urlPath))
+        switch ext {
+        case ".html":
+            w.Header().Set("Content-Type", "text/html")
+        case ".css":
+            w.Header().Set("Content-Type", "text/css")
+        case ".js":
+            w.Header().Set("Content-Type", "application/javascript")
+        case ".json":
+            w.Header().Set("Content-Type", "application/json")
+        }
+
+        http.ServeContent(w, r, urlPath, time.Time{}, f)
+    }
+} 

server/v2/server.go

@@ -8,12 +8,14 @@ import (
 	"path/filepath"
 	"strings"
 
+	"github.com/cosmos/cosmos-sdk/server/v2/api/swagger"
 	"github.com/pelletier/go-toml/v2"
 	"github.com/spf13/cobra"
 	"github.com/spf13/pflag"
 
 	"cosmossdk.io/core/transaction"
 	"cosmossdk.io/log"
+	"github.com/rakyll/statik/fs"
 )
 
 // ServerComponent is a server component that can be started and stopped.
@@ -73,6 +75,7 @@ var _ ServerComponent[transaction.Tx] = (*Server[transaction.Tx])(nil)
 type Server[T transaction.Tx] struct {
 	components []ServerComponent[T]
 	config     ServerConfig
+	router     *http.ServeMux
 }
 
 func NewServer[T transaction.Tx](
@@ -82,6 +85,7 @@ func NewServer[T transaction.Tx](
 	return &Server[T]{
 		config:     config,
 		components: components,
+		router:     http.NewServeMux(),
 	}
 }
 
@@ -242,3 +246,18 @@ func (s *Server[T]) StartFlags() []*pflag.FlagSet {
 
 	return flags
 }
+
+func (s *Server[T]) setupSwagger() error {
+	cfg := s.config.API.Swagger
+	if !cfg.Enable {
+		return nil
+	}
+
+	statikFS, err := fs.New()
+	if err != nil {
+		return err
+	}
+
+	s.router.PathPrefix(cfg.Path).Handler(swagger.Handler(statikFS))
+	return nil
+}