server

package
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 Go to latest Published: Aug 27, 2026 License: MIT Imports: 27 Imported by: 0

Documentation

Overview

Package server provides a net/http-shaped Go server with lifecycle, middleware, typed request binding, WebSocket integration, and optional Model Context Protocol (MCP) endpoints. Routes use http.ServeMux patterns, and handlers remain http.Handler values.

Use net/http directly when routes plus JSON are sufficient. Package server is useful when an application would otherwise assemble the same timeout, recovery, graceful shutdown, readiness, input, and protocol plumbing itself.

Index

Constants

View Source 
const (
	// LevelDebug enables debug-level logging with detailed information
	LevelDebug = slog.LevelDebug
	// LevelInfo enables info-level logging for general information
	LevelInfo = slog.LevelInfo
	// LevelWarn enables warning-level logging for important but non-critical events
	LevelWarn = slog.LevelWarn
	// LevelError enables error-level logging for error conditions only
	LevelError = slog.LevelError
)

Log level constants for server configuration. These wrap slog levels to provide a consistent API while hiding the logging implementation details.

Variables

View Source 
var (
	Version   = "dev"     // Version from git tags
	BuildHash = "unknown" // Git commit hash
	BuildTime = "unknown" // Build timestamp
)

Build information set at compile time using -ldflags

Functions

func Bind 

func Bind(r *http.Request, dst any) error

Bind picks the decoder based on Content-Type:

  • application/json → BindJSON
  • application/x-www-form-urlencoded or multipart/form-data → BindForm
  • otherwise → BindQuery

func BindForm 

func BindForm(r *http.Request, dst any) error

BindForm decodes application/x-www-form-urlencoded or multipart/form-data into dst, then runs Validate.

func BindJSON 

func BindJSON(r *http.Request, dst any) error

BindJSON decodes the request body as JSON into dst, then runs Validate. dst must be a non-nil pointer to a struct. Returns ValidationError when rules fail, and the wrapped error otherwise (decode error, etc.).

func BindQuery 

func BindQuery(r *http.Request, dst any) error

BindQuery decodes URL query parameters into dst (string keys → struct fields by json tag or lowercased name). Slices are populated from repeated keys. Then runs Validate.

func JSONEcho 

func JSONEcho[T any]() http.HandlerFunc

JSONEcho is the shorthand for the validate-and-pass-through case: bind the body into T, run validation, and echo the validated value back as the 200 response. Useful for webhook acks, dev stubs, and "did this payload validate?" endpoints where the response shape is the same as the input. 

srv.POST("/users", server.JSONEcho[CreateUser]())

Reach for JSONHandler[In, Out] when the response is genuinely different from the input — assigning a server-side ID, lowercasing the email, joining a related record. An identity function is the absence of business logic; JSONEcho says so directly.

Errors follow JSONHandler: *ValidationError → per-field 400 envelope, other bind errors → 400 with {"error": err.Error()}.

func JSONHandler 

func JSONHandler[In, Out any](fn func(context.Context, In) (Out, error)) http.HandlerFunc

JSONHandler wraps a typed business function as an http.HandlerFunc. It performs bind + validate + invoke + respond in a single step so handlers only contain business logic. 

srv.HandleFunc("POST /users", server.JSONHandler(
    func(ctx context.Context, in CreateUser) (User, error) {
        return createUser(ctx, in)
    },
))

func MCPDev 

func MCPDev() mcp.TransportConfig

MCPDev configures MCP with developer tools for local development.

SECURITY WARNING: Only use in development environments. Enables tools that can modify server behavior (log level, route introspection).

Tools provided:

  • mcp__hyperserve__server_control
  • mcp__hyperserve__route_inspector
  • mcp__hyperserve__dev_guide

Resources provided:

  • logs://server/stream, routes://server/all

func MCPObservability 

func MCPObservability() mcp.TransportConfig

MCPObservability configures MCP with observability resources for production use. This preset provides read-only access to system state with no control plane access:

  • config://server/current (sanitized server config, no secrets)
  • health://server/status (uptime and health metrics)
  • logs://server/recent (circular buffer of recent log entries)

func RecoveryMiddleware 

func RecoveryMiddleware(next http.Handler) http.Handler

RecoveryMiddleware returns a middleware function that recovers from panics in request handlers. Catches panics, logs the error, and returns a 500 Internal Server Error response.

func RequestLoggerMiddleware 

func RequestLoggerMiddleware(next http.Handler) http.Handler

RequestLoggerMiddleware returns a middleware function that logs structured request information. It captures and logs:

  • Client IP address
  • HTTP method and URL path
  • Trace ID (if present in X-Trace-ID header)
  • Response status code
  • Request duration
  • Response size in bytes

This middleware is included by default in NewServer(). For high-traffic applications, consider the performance impact of logging.

func SetBuiltinPresetHooks 

func SetBuiltinPresetHooks(tools, standardResources, observability, developer func(*Server))

SetBuiltinPresetHooks lets pkg/mcp/builtin (and only it, in practice) wire itself into the auto-registration flow used by NewServer when MCP is enabled. Pass nil for any preset you don't implement.

func Validate 

func Validate(dst any) error

Validate runs `validate:"..."` rules over dst (must be a pointer to a struct or a struct). Returns a *ValidationError when any rule fails, or nil otherwise. Nested structs are recursed into; pointers are dereferenced.

func VersionInfo 

func VersionInfo() string

VersionInfo returns formatted version information

Types

type CORSOptions 

type CORSOptions struct {
	AllowedOrigins   []string `json:"allowed_origins,omitempty"`
	AllowedMethods   []string `json:"allowed_methods,omitempty"`
	AllowedHeaders   []string `json:"allowed_headers,omitempty"`
	ExposeHeaders    []string `json:"expose_headers,omitempty"`
	AllowCredentials bool     `json:"allow_credentials,omitempty"`
	MaxAgeSeconds    int      `json:"max_age_seconds,omitempty"`
}

CORSOptions captures configuration for Cross-Origin Resource Sharing handling.

type DataFunc 

type DataFunc func(r *http.Request) any

DataFunc is a function type that generates data for template rendering. It receives the current HTTP request and returns data to be passed to the template.

type FieldError 

type FieldError = validate.FieldError

FieldError describes one failed validation rule. Aliased to the internal/validate type so pkg/mcp can produce the same errors when validating typed-tool arguments.

type Middleware 

type Middleware func(http.Handler) http.Handler

Middleware wraps an HTTP handler. It has the standard net/http middleware shape, so middleware from other packages works without an adapter.

func HeadersMiddleware 

func HeadersMiddleware(options Options) Middleware

HeadersMiddleware returns middleware for content-type, framing, referrer, permissions, cross-origin, HSTS, CSP, and configured CORS policy. Automatically handles CORS preflight requests.

func MetricsMiddleware 

func MetricsMiddleware(srv *Server) Middleware

MetricsMiddleware returns a middleware function that collects request metrics. It tracks total request count and response times for performance monitoring.

func RateLimitMiddleware 

func RateLimitMiddleware(srv *Server) Middleware

RateLimitMiddleware returns a middleware function that enforces rate limiting per client IP address. Uses token bucket algorithm with configurable rate limit and burst capacity. Returns 429 Too Many Requests when rate limit is exceeded. Optimized for Go 1.24's Swiss Tables map implementation.

func SecureWeb 

func SecureWeb(options Options) Middleware

SecureWeb is a convenience alias for HeadersMiddleware. Pass the Options snapshot from the Server whose TLS, CSP, CORS, and optional Server header policy should be applied.

type MiddlewareStack 

type MiddlewareStack []Middleware

MiddlewareStack is a collection of middleware functions that can be applied to an http.Handler. Middleware in the stack is applied in order, with the first middleware being the outermost.

type Option 

type Option func(*Server) error

Option configures a Server during construction.

func WithAddr 

func WithAddr(addr string) Option

WithAddr sets the address and port for the server to listen on. The address must be in the format "host:port" (e.g., ":8080", "localhost:3000").

func WithCORS 

func WithCORS(opts *CORSOptions) Option

WithCORS configures Cross-Origin Resource Sharing options for HTTP handlers.

func WithCSPWebWorkerSupport 

func WithCSPWebWorkerSupport() Option

WithCSPWebWorkerSupport enables Content Security Policy support for Web Workers using blob: URLs. This is required for modern web applications that use libraries like Tone.js, PDF.js, or other libraries that create Web Workers with blob: URLs for performance optimization. By default, this is disabled for security reasons and must be explicitly enabled.

func WithConfigFile 

func WithConfigFile(path string) Option

WithConfigFile overlays fields present in the JSON file at path. An explicit file is required to exist and contain one valid JSON object.

func WithDebugMode 

func WithDebugMode() Option

WithDebugMode enables debug logging and additional debug features. (The previously-exported WithLoglevel had no callers; use WithDebugMode or the HS_LOG_LEVEL env var to change the log level.)

func WithDeferredInit 

func WithDeferredInit(fn func(context.Context, *Server) error) Option

WithDeferredInit registers a callback that runs after the server listener is active but before the server is marked ready. While the callback is executing, non-health endpoints receive 503.

func WithDeferredInitStopOnFailure 

func WithDeferredInitStopOnFailure(stop bool) Option

WithDeferredInitStopOnFailure configures whether the server should shut down if the deferred initialization callback returns an error. Defaults to true.

func WithEnvironment 

func WithEnvironment() Option

WithEnvironment overlays supported SERVER_ADDR, HEALTH_ADDR, and HS_* variables. It does not consult HS_CONFIG_PATH; use WithConfigFile when the application chooses to read a file.

func WithFIPSMode 

func WithFIPSMode() Option

WithFIPSMode restricts the TLS handshake to FIPS-approved cipher suites and elliptic curves.

This is NOT full FIPS 140-3 compliance:

  • it does not switch the Go toolchain into FIPS mode (build with GOFIPS140 for that);
  • it does not constrain non-TLS crypto (hashes, RNGs, signatures outside TLS);
  • it does not invoke a FIPS-validated cryptographic module.

Use this for "TLS handshake uses FIPS-approved primitives." For deployments that require true FIPS 140-3 compliance, combine with a FIPS-validated toolchain build.

func WithHealthAddr 

func WithHealthAddr(addr string) Option

WithHealthAddr sets the address for the separate health server.

func WithHealthServer 

func WithHealthServer() Option

WithHealthServer enables the health server on a separate port. The health server provides /healthz/, /readyz/, and /livez/ endpoints for monitoring.

func WithLogLevel 

func WithLogLevel(level string) Option

WithLogLevel sets the configured server log level. Accepted values are DEBUG, INFO, WARN, and ERROR.

func WithLogger 

func WithLogger(l *slog.Logger) Option

WithLogger gives one Server its logger without changing slog's process-wide default. Configure the handler's level in the application when supplying a custom logger.

func WithMCPBuiltinResources 

func WithMCPBuiltinResources(enabled bool) Option

WithMCPBuiltinResources toggles the built-in MCP resources (Config, Metrics, System, ServerLog, ServerHealth). Default off. Same blank-import requirement as WithMCPBuiltinTools.

func WithMCPBuiltinTools 

func WithMCPBuiltinTools(enabled bool) Option

WithMCPBuiltinTools toggles the built-in MCP tools (Calculator plus sandboxed FileRead / ListDirectory when WithMCPFileToolRoot is set). Default off. Requires `_ "github.com/osauer/hyperserve/v2/pkg/mcp/builtin"` to be blank-imported by the consumer; otherwise NewServer logs a warning and registers nothing.

func WithMCPDiscoveryFilter 

func WithMCPDiscoveryFilter(filter func(toolName string, r *http.Request) bool) Option

WithMCPDiscoveryFilter sets a custom filter function for MCP discovery.

The filter function receives the tool name and HTTP request, allowing for context-aware filtering based on auth tokens, IP addresses, etc.

Example - Hide admin tools from external requests: 

srv, _ := server.NewServer(
    server.WithMCPDiscoveryFilter(func(toolName string, r *http.Request) bool {
        if strings.Contains(toolName, "admin") {
            return strings.HasPrefix(r.RemoteAddr, "10.") ||
                   strings.HasPrefix(r.RemoteAddr, "192.168.")
        }
        return true
    }),
)

func WithMCPDiscoveryPolicy 

func WithMCPDiscoveryPolicy(policy mcp.DiscoveryPolicy) Option

WithMCPDiscoveryPolicy sets the discovery policy for MCP tools and resources.

Example: 

srv, _ := server.NewServer(
    server.WithMCPDiscoveryPolicy(mcp.DiscoveryCount),
)

func WithMCPEndpoint 

func WithMCPEndpoint(endpoint string) Option

WithMCPEndpoint configures the MCP endpoint path. Default is "/mcp".

func WithMCPFileToolRoot 

func WithMCPFileToolRoot(rootDir string) Option

WithMCPFileToolRoot scopes MCP file tools to rootDir via os.Root, so they cannot read or list paths outside it.

func WithMCPLegacyRoutedSSE deprecated 

func WithMCPLegacyRoutedSSE(enabled bool) Option

WithMCPLegacyRoutedSSE enables HyperServe's proprietary X-SSE-* routed transport. It is disabled by default and should be used only while clients migrate to MCP 2026-07-28 Streamable HTTP subscriptions/listen.

Deprecated: use MCP 2026-07-28 Streamable HTTP.

func WithMCPOriginValidator 

func WithMCPOriginValidator(validator func(*http.Request) bool) Option

WithMCPOriginValidator overrides MCP's default same-origin browser policy. The validator receives every MCP request and should allow requests without Origin when non-browser clients are expected. Use an explicit allowlist and do not trust Origin as authentication. Passing nil restores the default.

func WithMCPProtocolVersion 

func WithMCPProtocolVersion(version string) Option

WithMCPProtocolVersion overrides the MCP protocol version advertised to clients. Empty values reset to mcp.DefaultProtocolVersion.

func WithMCPSupport 

func WithMCPSupport(name, version string, configs ...mcp.TransportConfig) Option

WithMCPSupport enables MCP (Model Context Protocol) support on the server. Server name and version identify the server to MCP clients. By default, MCP uses HTTP transport on the "/mcp" endpoint; pass mcp.TransportConfig values to switch to stdio or to install a preset (DeveloperMode, ObservabilityMode).

Example: 

server.NewServer(server.WithMCPSupport("MyServer", "1.0.0"))

func WithMCPToolCallTimeout 

func WithMCPToolCallTimeout(d time.Duration) Option

WithMCPToolCallTimeout sets the per-tool execution budget enforced by the MCP handler. Tools that exceed the timeout return context.DeadlineExceeded to the caller; see the caveat in contextToolWrapper for what happens to the underlying goroutine. Zero or negative values fall back to the package default (30s).

func WithOnReady 

func WithOnReady(hook func(context.Context, *Server) error) Option

WithOnReady registers hooks that run after deferred initialization succeeds but before the server is marked ready. Hooks are executed sequentially in the order they were registered.

func WithOnShutdown 

func WithOnShutdown(hook func(context.Context) error) Option

WithOnShutdown registers a function to be called when the server begins shutdown. Multiple hooks can be registered and are executed sequentially in the order they were added. Hooks are called before the HTTP server shutdown begins, allowing applications to cleanly stop their own goroutines and release resources.

Each hook receives a context with a timeout (typically 5 seconds of the total 10-second shutdown budget). Hooks should respect the context deadline and return promptly. Errors from hooks are logged but don't prevent shutdown from proceeding.

Example: 

srv, _ := server.NewServer(
	server.WithOnShutdown(func(ctx context.Context) error {
		log.Println("Stopping background workers...")
		return stopWorkers(ctx)
	}),
)

func WithOptions 

func WithOptions(options Options) Option

WithOptions replaces the current option snapshot with a defensive copy of options. Options passed later to NewServer override this snapshot.

func WithRateLimit 

func WithRateLimit(limit RateLimit, burst int) Option

WithRateLimit configures rate limiting for the server. limit: maximum number of requests per second per client IP burst: maximum number of requests that can be made in a short burst

func WithServerHeader 

func WithServerHeader(value string) Option

WithServerHeader opts into a Server response header when HeadersMiddleware is installed. The empty string omits identification. Invalid HTTP control bytes cause NewServer to return an error.

func WithStartupBanner 

func WithStartupBanner() Option

WithStartupBanner opts into HyperServe's ASCII startup banner. Library consumers are silent by default apart from configured structured logs.

func WithStaticDir 

func WithStaticDir(dir string) Option

WithStaticDir sets the directory root used by Server.HandleStatic. The directory is opened and validated when the static route is registered.

func WithTLS 

func WithTLS(certFile, keyFile string) Option

WithTLS enables TLS on the server with the specified certificate and key files. Returns a Option that configures TLS settings and validates file existence.

func WithTemplateDir 

func WithTemplateDir(dir string) Option

WithTemplateDir sets the directory path where HTML templates are located. Templates in this directory can be used with HandleTemplate and HandleFuncDynamic methods. Returns an error if the specified directory does not exist or is not accessible.

func WithTimeouts 

func WithTimeouts(readTimeout, writeTimeout, idleTimeout time.Duration) Option

WithTimeouts configures the HTTP server timeouts. readTimeout: maximum duration for reading the entire request writeTimeout: maximum duration before timing out writes of the response idleTimeout: maximum time to wait for the next request when keep-alives are enabled

type Options 

type Options struct {
	Addr              string        `json:"addr,omitempty"`
	EnableTLS         bool          `json:"tls,omitempty"`
	TLSAddr           string        `json:"tls_addr,omitempty"`
	KeyFile           string        `json:"key_file,omitempty"`
	CertFile          string        `json:"cert_file,omitempty"`
	HealthAddr        string        `json:"health_addr,omitempty"`
	RateLimit         RateLimit     `json:"rate_limit,omitempty"`
	Burst             int           `json:"burst,omitempty"`
	ReadTimeout       time.Duration `json:"read_timeout,omitempty"`
	WriteTimeout      time.Duration `json:"write_timeout,omitempty"`
	IdleTimeout       time.Duration `json:"idle_timeout,omitempty"`
	ReadHeaderTimeout time.Duration `json:"read_header_timeout,omitempty"`
	StaticDir         string        `json:"static_dir,omitempty"`
	TemplateDir       string        `json:"template_dir,omitempty"`
	RunHealthServer   bool          `json:"run_health_server,omitempty"`
	FIPSMode          bool          `json:"fips_mode,omitempty"`
	// ServerHeader is emitted by HeadersMiddleware when non-empty.
	ServerHeader string `json:"server_header,omitempty"`
	// MCP (Model Context Protocol) configuration
	MCPEnabled          bool                                        `json:"mcp_enabled,omitempty"`
	MCPEndpoint         string                                      `json:"mcp_endpoint,omitempty"`
	MCPServerName       string                                      `json:"mcp_server_name,omitempty"`
	MCPServerVersion    string                                      `json:"mcp_server_version,omitempty"`
	MCPToolsEnabled     bool                                        `json:"mcp_tools_enabled,omitempty"`
	MCPResourcesEnabled bool                                        `json:"mcp_resources_enabled,omitempty"`
	MCPFileToolRoot     string                                      `json:"mcp_file_tool_root,omitempty"`
	MCPLogResourceSize  int                                         `json:"mcp_log_resource_size,omitempty"`
	MCPToolCallTimeout  time.Duration                               `json:"mcp_tool_call_timeout,omitempty"`
	MCPTransport        mcp.TransportType                           `json:"mcp_transport,omitempty"`
	MCPProtocolVersion  string                                      `json:"mcp_protocol_version,omitempty"`
	MCPLegacyRoutedSSE  bool                                        `json:"mcp_legacy_routed_sse,omitempty"`
	MCPDev              bool                                        `json:"mcp_dev,omitempty"`
	MCPObservability    bool                                        `json:"mcp_observability,omitempty"`
	MCPDiscoveryPolicy  mcp.DiscoveryPolicy                         `json:"mcp_discovery_policy,omitempty"`
	MCPDiscoveryFilter  func(toolName string, r *http.Request) bool `json:"-"` // Custom filter function
	MCPOriginValidator  func(r *http.Request) bool                  `json:"-"`

	// CSP (Content Security Policy) configuration
	CSPWebWorkerSupport bool         `json:"csp_web_worker_support,omitempty"`
	CORS                *CORSOptions `json:"cors,omitempty"`
	// Logging configuration
	LogLevel  string `json:"log_level,omitempty"`
	DebugMode bool   `json:"debug_mode,omitempty"`
	// Banner configuration
	StartupBanner bool `json:"startup_banner,omitempty"`
	BannerColor   bool `json:"banner_color,omitempty"`

	// OnShutdownHooks are functions called when the server begins shutdown.
	// Hooks are executed sequentially in the order they were added, before HTTP server shutdown.
	// Each hook receives a context with timeout and should respect the deadline.
	// Errors from hooks are logged but don't prevent shutdown.
	OnShutdownHooks []func(context.Context) error `json:"-"`

	// OnReadyHooks run after deferred initialization succeeds and before the server is marked ready.
	OnReadyHooks []func(context.Context, *Server) error `json:"-"`
	// StopOnDeferredInitFailure indicates whether the server should shut down if deferred init fails.
	StopOnDeferredInitFailure bool `json:"stop_on_deferred_init_failure,omitempty"`
	// contains filtered or unexported fields
}

Options contains all configuration settings for the HTTP server. Values can be set via WithXXX functions when creating a new server. Bind a configuration file or environment variables explicitly with WithConfigFile or WithEnvironment.

Use DefaultOptions to obtain HyperServe's defaults before modifying a complete snapshot; a zero Options value is not implicitly filled.

func DefaultOptions 

func DefaultOptions() Options

DefaultOptions returns an independent copy of HyperServe's deterministic defaults. Nested slices and CORS configuration are cloned so callers may safely modify the result before passing it to WithOptions.

type RateLimit 

type RateLimit = rate.Limit

RateLimit limits requests per second that can be requested from the httpServer. Requires to add RateLimitMiddleware

type SSEMessage 

type SSEMessage struct {
	Event string `json:"event"` // Optional: Allows sending multiple event types
	Data  any    `json:"data"`  // The actual data payload
}

SSEMessage represents a Server-Sent Events message with an optional event type and data payload. It follows the SSE format with event and data fields that can be sent to clients.

func NewSSEMessage 

func NewSSEMessage(data any) *SSEMessage

NewSSEMessage creates a new SSE message with the given data and a default "message" event type. This is a convenience function for creating standard SSE messages.

func (*SSEMessage) String 

func (sse *SSEMessage) String() string

String formats the SSE message according to the Server-Sent Events specification. Multi-line data is emitted as one data field per line.

type Server 

type Server struct {
	// contains filtered or unexported fields
}

Server represents an HTTP server with built-in middleware support, health checks, template rendering, and various configuration options.

The Server manages both the main HTTP server and an optional health check server. It handles graceful shutdown, request metrics, and can be extended with custom middleware.

Example: 

srv, _ := server.NewServer(
	server.WithAddr(":8080"),
	server.WithHealthServer(),
)

srv.HandleFunc("/api/users", handleUsers)
if err := srv.Run(ctx); err != nil {
	log.Fatal(err)
}

func NewServer 

func NewServer(opts ...Option) (*Server, error)

NewServer creates a new instance of the Server with the given options. By default, the server includes request logging, panic recovery, and metrics collection middleware. The server will listen on ":8080" unless configured otherwise.

Options can be provided to customize the server behavior: 

srv, err := server.NewServer(
	server.WithAddr(":3000"),
	server.WithHealthServer(),          // Enable health checks on :8081
	server.WithTLS("cert.pem", "key.pem"), // Enable HTTPS
	server.WithRateLimit(100, 200),     // 100 req/s, burst of 200
)

Returns an error if any of the options fail to apply.

func (*Server) AddMetrics 

func (srv *Server) AddMetrics(deltaRequests uint64, deltaResponseTime int64)

AddMetrics is a test affordance: it bumps the request count by one and adds to the cumulative response time. See SetMetrics.

func (*Server) ClientLimiterCount 

func (srv *Server) ClientLimiterCount() int

ClientLimiterCount returns the number of active per-client rate limiters.

func (*Server) CompleteDeferredInit 

func (srv *Server) CompleteDeferredInit(ctx context.Context, err error) error

CompleteDeferredInit allows applications to manually finalize deferred initialization after addressing failures. Passing a nil error reruns any pending OnReady hooks and marks the server ready. Passing a non-nil error records the failure and leaves the server in an initializing state.

func (*Server) DELETE 

func (srv *Server) DELETE(pattern string, handler http.HandlerFunc)

DELETE registers handler for DELETE requests matching pattern.

func (*Server) GET 

func (srv *Server) GET(pattern string, handler http.HandlerFunc)

GET registers handler for GET requests matching pattern.

func (*Server) HEAD 

func (srv *Server) HEAD(pattern string, handler http.HandlerFunc)

HEAD registers handler for HEAD requests matching pattern.

func (*Server) Handle 

func (srv *Server) Handle(pattern string, handler http.Handler)

Handle registers an http.Handler for the given pattern. Mirrors http.ServeMux.Handle but also tracks the pattern so prefix middleware can find it. Use this when you have an existing http.Handler (e.g., http.FileServer); use HandleFunc for inline handler functions. 

srv.Handle("/static/", http.StripPrefix("/static/", http.FileServer(http.Dir("./static"))))

func (*Server) HandleFunc 

func (srv *Server) HandleFunc(pattern string, handler http.HandlerFunc)

func (*Server) HandleFuncDynamic 

func (srv *Server) HandleFuncDynamic(pattern, tmplName string, dataFunc DataFunc) error

HandleFuncDynamic registers a handler that renders templates with dynamic data. The dataFunc is called for each request to generate the data passed to the template. Returns an error if template parsing fails.

func (*Server) HandleStatic 

func (srv *Server) HandleStatic(pattern string) error

HandleStatic registers a handler that serves files only through an os.Root confined to Options.StaticDir. It returns an error without registering the route if the configured root cannot be opened.

func (*Server) HandleTemplate 

func (srv *Server) HandleTemplate(pattern, t string, data any) error

HandleTemplate registers a handler that renders a specific template with static data. Unlike HandleFuncDynamic, the data is provided once at registration time. Returns an error if template parsing fails.

func (*Server) Handler 

func (srv *Server) Handler() http.Handler

Handler returns an ordinary http.Handler. Middleware registration remains open until the handler serves its first request, then its compiled plan and the server's middleware configuration are frozen.

func (*Server) IsReady 

func (srv *Server) IsReady() bool

IsReady reports whether the server is ready to accept traffic.

func (*Server) IsRunning 

func (srv *Server) IsRunning() bool

IsRunning reports whether the server is currently running.

func (*Server) MCPEnabled 

func (srv *Server) MCPEnabled() bool

MCPEnabled reports whether MCP support has been initialized for this server.

func (*Server) MCPHandler 

func (srv *Server) MCPHandler() *mcp.Handler

MCPHandler returns the MCP handler attached to this server, or nil if MCP is not enabled.

func (*Server) MiddlewareRoutes 

func (srv *Server) MiddlewareRoutes() map[string]MiddlewareStack

MiddlewareRoutes returns a snapshot of the registered route-to-middleware mapping. The map and its stacks are independent snapshots.

func (*Server) OPTIONS 

func (srv *Server) OPTIONS(pattern string, handler http.HandlerFunc)

OPTIONS registers handler for OPTIONS requests matching pattern.

func (*Server) Options 

func (srv *Server) Options() Options

Options returns an independent snapshot of the server configuration. Mutating the returned value does not reconfigure the running server.

func (*Server) PATCH 

func (srv *Server) PATCH(pattern string, handler http.HandlerFunc)

PATCH registers handler for PATCH requests matching pattern.

func (*Server) POST 

func (srv *Server) POST(pattern string, handler http.HandlerFunc)

POST registers handler for POST requests matching pattern.

func (*Server) PUT 

func (srv *Server) PUT(pattern string, handler http.HandlerFunc)

PUT registers handler for PUT requests matching pattern.

func (*Server) RegisterMCPExtension 

func (srv *Server) RegisterMCPExtension(ext mcp.Extension) error

RegisterMCPExtension registers all tools and resources from an extension.

func (*Server) RegisterMCPNamespace 

func (srv *Server) RegisterMCPNamespace(name string, configs ...mcp.NamespaceConfig) error

RegisterMCPNamespace registers an entire MCP namespace with its tools and resources. Per-tool/per-resource namespace registration goes through this path — callers that need a single tool in a namespace pass it inside a NamespaceConfig rather than reaching for two separate helpers.

func (*Server) RegisterMCPResource 

func (srv *Server) RegisterMCPResource(resource mcp.Resource) error

RegisterMCPResource registers a custom MCP resource.

func (*Server) RegisterMCPResourceTemplate 

func (srv *Server) RegisterMCPResourceTemplate(template mcp.ResourceTemplate) error

RegisterMCPResourceTemplate registers a custom MCP resource template.

func (*Server) RegisterMCPTool 

func (srv *Server) RegisterMCPTool(tool mcp.Tool) error

RegisterMCPTool registers a custom MCP tool. Must be called after server creation but before Run().

func (*Server) RegisteredRoutes 

func (srv *Server) RegisteredRoutes() []string

RegisteredRoutes returns a sorted snapshot of patterns registered through Handle, HandleFunc, and the method-aware route helpers.

func (*Server) Run 

func (srv *Server) Run(ctx context.Context) error

Run starts the HTTP/HTTPS server and blocks until ctx requests a graceful shutdown, the server exits, or deferred initialization fails. It does not subscribe to process signals; the application owns the lifecycle. The context is a shutdown trigger; its values are not installed as HTTP request values. Use middleware for request-scoped data. Cancellation is a normal shutdown trigger and returns nil when shutdown succeeds. Run returns an error for MCP stdio transport because a context cannot portably interrupt its blocking stdin read; use RunStdio instead. A Server must not be run concurrently or reused after Run returns.

func (*Server) RunStdio 

func (srv *Server) RunStdio() error

RunStdio runs an MCP stdio server until stdin reaches EOF. Stdio is kept separate from Run because an arbitrary io.Reader cannot be interrupted by a context without closing an object the application may own.

func (*Server) ServerStart 

func (srv *Server) ServerStart() time.Time

ServerStart returns the timestamp when the server began serving.

func (*Server) SetMetrics 

func (srv *Server) SetMetrics(totalRequests uint64, totalResponseTime int64)

SetMetrics is a test affordance: it overrides the request count and cumulative response time. Production code should never call this; metrics are populated by the request-handling middleware.

func (*Server) Shutdown 

func (srv *Server) Shutdown(ctx context.Context) error

Shutdown gracefully stops the server within the caller's deadline.

func (*Server) TotalRequests 

func (srv *Server) TotalRequests() uint64

TotalRequests returns the total number of requests served so far.

func (*Server) TotalResponseTime 

func (srv *Server) TotalResponseTime() int64

TotalResponseTime returns the cumulative response time in microseconds.

func (*Server) Use 

func (srv *Server) Use(middleware ...Middleware)

Use registers middleware for every request. Middleware is applied in the order provided, with the first item outermost. Register middleware before calling Run or serving Handler; registration after serving starts panics.

func (*Server) UsePrefix 

func (srv *Server) UsePrefix(prefix string, middleware ...Middleware)

UsePrefix registers middleware for a URL path and its child paths at a slash boundary. For example, "/api" matches "/api/users" but not "/apiv2". Register middleware before calling Run or serving Handler; registration after serving starts panics.

func (*Server) WebSocketUpgrader 

func (srv *Server) WebSocketUpgrader() *websocket.Upgrader

WebSocketUpgrader returns a WebSocket upgrader that tracks the upgrade in server telemetry. Use this instead of a standalone Upgrader so WS upgrades land in totalWebSocketUpgrades alongside the totalRequests counter that MetricsMiddleware already maintains for every request.

type StatusError 

type StatusError struct {
	Code    int
	Message string
	Err     error
}

StatusError carries an HTTP status code so handler errors can opt into a specific 4xx/5xx response without inventing a new error type per call site. Use NewStatusError, or any error that implements `HTTPStatus() int`.

func NewStatusError 

func NewStatusError(code int, message string) *StatusError

NewStatusError builds a StatusError. Message is the public string sent in the response body; pass an empty message to fall back to http.StatusText.

func (*StatusError) Error 

func (e *StatusError) Error() string

Error implements error.

func (*StatusError) HTTPStatus 

func (e *StatusError) HTTPStatus() int

HTTPStatus is the contract JSONHandler keys off when mapping handler errors to response codes.

func (*StatusError) Unwrap 

func (e *StatusError) Unwrap() error

Unwrap exposes the inner cause for errors.Is / errors.As.

type ValidationError 

type ValidationError = validate.ValidationError

ValidationError is the aggregate error returned by Validate / Bind* when one or more fields fail their rules. Aliased to internal/validate.

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