README

Caddy 2

This is the development branch for Caddy 2, the web server of the Go community.

Caddy 2 is production-ready, but there may be breaking changes before the stable 2.0 release. Please test it and deploy it as much as you are able, and submit your feedback!


Caddy

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Caddy is an extensible server platform that uses TLS by default.


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Build from source

Requirements:

For development
$ git clone -b v2 "https://github.com/caddyserver/caddy.git"
$ cd caddy/cmd/caddy/
$ go build

Note: Those steps will not embed proper version information. For that, please follow the instructions below.

With version information and/or plugins
  1. Create a new folder: mkdir caddy
  2. Change into it: cd caddy
  3. Copy Caddy's main.go into the empty folder. Add imports for any custom plugins you want to add.
  4. Initialize a Go module: go mod init caddy
  5. Pin Caddy version: go get github.com/caddyserver/caddy/v2@TAG replacing TAG with a git tag or commit.
  6. Compile: go build

Quick start

The Caddy website has documentation that includes tutorials, quick-start guides, reference, and more.

We recommend that all users do our Getting Started guide to become familiar with using Caddy.

If you've only got a minute, the website has several quick-start tutorials to choose from! However, after finishing a quick-start tutorial, please read more documentation to understand how the software works. 🙂

Overview

Caddy is most often used as an HTTPS server, but it is suitable for any long-running Go program. First and foremost, it is a platform to run Go applications. Caddy "apps" are just Go programs that are implemented as Caddy modules. Two apps -- tls and http -- ship standard with Caddy.

Caddy apps instantly benefit from automated documentation, graceful on-line config changes via API, and unification with other Caddy apps.

Although JSON is Caddy's native config language, Caddy can accept input from config adapters which can essentially convert any config format of your choice into JSON: Caddyfile, JSON 5, YAML, TOML, NGINX config, and more.

The primary way to configure Caddy is through its API, but if you prefer config files, the command-line interface supports those too.

Caddy exposes an unprecedented level of control compared to any web server in existence. In Caddy, you are usually setting the actual values of the initialized types in memory that power everything from your HTTP handlers and TLS handshakes to your storage medium. Caddy is also ridiculously extensible, with a powerful plugin system that makes vast improvements over other web servers.

To wield the power of this design, you need to know how the config document is structured. Please see the our documentation site for details about Caddy's config structure.

Nearly all of Caddy's configuration is contained in a single config document, rather than being scattered across CLI flags and env variables and a configuration file as with other web servers. This makes managing your server config more straightforward and reduces hidden variables/factors.

Full documentation

Our website has complete documentation:

https://caddyserver.com/docs/

The docs are also open source. You can contribute to them here: https://github.com/caddyserver/website

Getting help

  • We strongly recommend that all professionals or companies using Caddy get a support contract through Ardan Labs before help is needed.

  • Individuals can exchange help for free on our community forum at https://caddy.community. Remember that people give help out of their spare time and good will. The best way to get help is to give it first!

Please use our issue tracker only for bug reports and feature requests, i.e. actionable development items (support questions will usually be referred to the forums).

About

The name "Caddy" is trademarked. The name of the software is "Caddy", not "Caddy Server" or "CaddyServer". Please call it "Caddy" or, if you wish to clarify, "the Caddy web server". Caddy is a registered trademark of Light Code Labs, LLC.

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Documentation

Index

Examples

Constants

const (
	ExitCodeSuccess = iota
	ExitCodeFailedStartup
	ExitCodeForceQuit
	ExitCodeFailedQuit
)

Exit codes. Generally, you should NOT automatically restart the process if the exit code is ExitCodeFailedStartup (1).


const ImportPath = "github.com/Unotechsoftware/caddy/v2"

ImportPath is the package import path for Caddy core.


Variables

var (
	// DefaultAdminListen is the address for the admin
	// listener, if none is specified at startup.
	DefaultAdminListen = "localhost:2019"

	// ErrInternalRedir indicates an internal redirect
	// and is useful when admin API handlers rewrite
	// the request; in that case, authentication and
	// authorization needs to happen again for the
	// rewritten request.
	ErrInternalRedir = fmt.Errorf("internal redirect; re-authorization required")

	// DefaultAdminConfig is the default configuration
	// for the administration endpoint.
	DefaultAdminConfig = &AdminConfig{
		Listen: DefaultAdminListen,
	}
)

var ConfigAutosavePath = filepath.Join(AppConfigDir(), "autosave.json")

ConfigAutosavePath is the default path to which the last config will be persisted.


Functions

func AppConfigDir

func AppConfigDir() string

AppConfigDir returns the directory where to store user's config.

If XDG_CONFIG_HOME is set, it returns: $XDG_CONFIG_HOME/caddy. Otherwise, os.UserConfigDir() is used; if successful, it appends "Caddy" (Windows & Mac) or "caddy" (every other OS) to the path. If it returns an error, the fallback path "./caddy" is returned.

The config directory is not guaranteed to be different from AppDataDir().

Unlike os.UserConfigDir(), this function prefers the XDG_CONFIG_HOME env var on all platforms, not just Unix.

Ref: https://specifications.freedesktop.org/basedir-spec/basedir-spec-latest.html

func AppDataDir

func AppDataDir() string

AppDataDir returns a directory path that is suitable for storing application data on disk. It uses the environment for finding the best place to store data, and appends a "caddy" or "Caddy" (depending on OS and environment) subdirectory.

For a base directory path: If XDG_DATA_HOME is set, it returns: $XDG_DATA_HOME/caddy; otherwise, on Windows it returns: %AppData%/Caddy, on Mac: $HOME/Library/Application Support/Caddy, on Plan9: $home/lib/caddy, on Android: $HOME/caddy, and on everything else: $HOME/.local/share/caddy.

If a data directory cannot be determined, it returns "./caddy" (this is not ideal, and the environment should be fixed).

The data directory is not guaranteed to be different from AppConfigDir().

Ref: https://specifications.freedesktop.org/basedir-spec/basedir-spec-latest.html

func GetModuleID

func GetModuleID(instance interface{}) string

GetModuleID returns a module's ID from an instance of its value. If the value is not a module, an empty string will be returned.

func GetModuleName

func GetModuleName(instance interface{}) string

GetModuleName returns a module's name (the last label of its ID) from an instance of its value. If the value is not a module, an empty string will be returned.

func GoModule

func GoModule() *debug.Module

GoModule returns the build info of this Caddy build from debug.BuildInfo (requires Go modules). If no version information is available, a non-nil value will still be returned, but with an unknown version.

func HomeDir

func HomeDir() string

HomeDir returns the best guess of the current user's home directory from environment variables. If unknown, "." (the current directory) is returned instead, except GOOS=android, which returns "/sdcard".

func JoinNetworkAddress

func JoinNetworkAddress(network, host, port string) string

JoinNetworkAddress combines network, host, and port into a single address string of the form accepted by ParseNetworkAddress(). For unix sockets, the network should be "unix" (or "unixgram" or "unixpacket") and the path to the socket should be given as the host parameter.

func Listen

func Listen(network, addr string) (net.Listener, error)

Listen returns a listener suitable for use in a Caddy module. Always be sure to close listeners when you are done with them.

func ListenPacket

func ListenPacket(network, addr string) (net.PacketConn, error)

ListenPacket returns a net.PacketConn suitable for use in a Caddy module. Always be sure to close the PacketConn when you are done.

func Load

func Load(cfgJSON []byte, forceReload bool) error

Load loads the given config JSON and runs it only if it is different from the current config or forceReload is true.

func Log

func Log() *zap.Logger

Log returns the current default logger.

func Modules

func Modules() []string

Modules returns the names of all registered modules in ascending lexicographical order.

func ParseStructTag

func ParseStructTag(tag string) (map[string]string, error)

ParseStructTag parses a caddy struct tag into its keys and values. It is very simple. The expected syntax is: `caddy:"key1=val1 key2=val2 ..."`

func RegisterModule

func RegisterModule(instance Module) error

RegisterModule registers a module by receiving a plain/empty value of the module. For registration to be properly recorded, this should be called in the init phase of runtime. Typically, the module package will do this as a side-effect of being imported. This function returns an error if the module's info is incomplete or invalid, or if the module is already registered.

func RemoveMetaFields

func RemoveMetaFields(rawJSON []byte) []byte

RemoveMetaFields removes meta fields like "@id" from a JSON message by using a simple regular expression. (An alternate way to do this would be to delete them from the raw, map[string]interface{} representation as they are indexed, then iterate the index we made and add them back after encoding as JSON, but this is simpler.)

func Run

func Run(cfg *Config) error

Run runs the given config, replacing any existing config.

func SplitNetworkAddress

func SplitNetworkAddress(a string) (network, host, port string, err error)

SplitNetworkAddress splits a into its network, host, and port components. Note that port may be a port range (:X-Y), or omitted for unix sockets.

func Stop

func Stop() error

Stop stops running the current configuration. It is the antithesis of Run(). This function will log any errors that occur during the stopping of individual apps and continue to stop the others. Stop should only be called if not replacing with a new config.

func TrapSignals

func TrapSignals()

TrapSignals create signal/interrupt handlers as best it can for the current OS. This is a rather invasive function to call in a Go program that captures signals already, so in that case it would be better to implement these handlers yourself.

func Validate

func Validate(cfg *Config) error

Validate loads, provisions, and validates cfg, but does not start running it.

Types

type APIError

type APIError struct {
	Code    int    `json:"-"`
	Err     error  `json:"-"`
	Message string `json:"error"`
}

APIError is a structured error that every API handler should return for consistency in logging and client responses. If Message is unset, then Err.Error() will be serialized in its place.

func (APIError) Error

func (e APIError) Error() string

type AdminConfig

type AdminConfig struct {
	// If true, the admin endpoint will be completely disabled.
	// Note that this makes any runtime changes to the config
	// impossible, since the interface to do so is through the
	// admin endpoint.
	Disabled bool `json:"disabled,omitempty"`

	// The address to which the admin endpoint's listener should
	// bind itself. Can be any single network address that can be
	// parsed by Caddy. Default: localhost:2019
	Listen string `json:"listen,omitempty"`

	// If true, CORS headers will be emitted, and requests to the
	// API will be rejected if their `Host` and `Origin` headers
	// do not match the expected value(s). Use `origins` to
	// customize which origins/hosts are allowed.If `origins` is
	// not set, the listen address is the only value allowed by
	// default.
	EnforceOrigin bool `json:"enforce_origin,omitempty"`

	// The list of allowed origins for API requests. Only used if
	// `enforce_origin` is true. If not set, the listener address
	// will be the default value. If set but empty, no origins will
	// be allowed.
	Origins []string `json:"origins,omitempty"`

	// Options related to configuration management.
	Config *ConfigSettings `json:"config,omitempty"`
}

AdminConfig configures Caddy's API endpoint, which is used to manage Caddy while it is running.

type AdminHandler

type AdminHandler interface {
	ServeHTTP(http.ResponseWriter, *http.Request) error
}

AdminHandler is like http.Handler except ServeHTTP may return an error.

If any handler encounters an error, it should be returned for proper handling.

type AdminHandlerFunc

type AdminHandlerFunc func(http.ResponseWriter, *http.Request) error

AdminHandlerFunc is a convenience type like http.HandlerFunc.

func (AdminHandlerFunc) ServeHTTP

func (f AdminHandlerFunc) ServeHTTP(w http.ResponseWriter, r *http.Request) error

ServeHTTP implements the Handler interface.

type AdminRoute

type AdminRoute struct {
	Pattern string
	Handler AdminHandler
}

AdminRoute represents a route for the admin endpoint.

type AdminRouter

type AdminRouter interface {
	Routes() []AdminRoute
}

AdminRouter is a type which can return routes for the admin API.

type App

type App interface {
	Start() error
	Stop() error
}

App is a thing that Caddy runs.

type CleanerUpper

type CleanerUpper interface {
	Cleanup() error
}

CleanerUpper is implemented by modules which may have side-effects such as opened files, spawned goroutines, or allocated some sort of non-stack state when they were provisioned. This method should deallocate/cleanup those resources to prevent memory leaks. Cleanup should be fast and efficient. Cleanup should work even if Provision returns an error, to allow cleaning up from partial provisionings.

type Config

type Config struct {
	Admin   *AdminConfig `json:"admin,omitempty"`
	Logging *Logging     `json:"logging,omitempty"`

	// StorageRaw is a storage module that defines how/where Caddy
	// stores assets (such as TLS certificates). The default storage
	// module is `caddy.storage.file_system` (the local file system),
	// and the default path
	// [depends on the OS and environment](/docs/conventions#data-directory).
	StorageRaw json.RawMessage `json:"storage,omitempty" caddy:"namespace=caddy.storage inline_key=module"`

	// AppsRaw are the apps that Caddy will load and run. The
	// app module name is the key, and the app's config is the
	// associated value.
	AppsRaw ModuleMap `json:"apps,omitempty" caddy:"namespace="`
	// contains filtered or unexported fields
}

Config is the top (or beginning) of the Caddy configuration structure. Caddy config is expressed natively as a JSON document. If you prefer not to work with JSON directly, there are [many config adapters](/docs/config-adapters) available that can convert various inputs into Caddy JSON.

Many parts of this config are extensible through the use of Caddy modules. Fields which have a json.RawMessage type and which appear as dots (•••) in the online docs can be fulfilled by modules in a certain module namespace. The docs show which modules can be used in a given place.

Whenever a module is used, its name must be given either inline as part of the module, or as the key to the module's value. The docs will make it clear which to use.

Generally, all config settings are optional, as it is Caddy convention to have good, documented default values. If a parameter is required, the docs should say so.

Go programs which are directly building a Config struct value should take care to populate the JSON-encodable fields of the struct (i.e. the fields with `json` struct tags) if employing the module lifecycle (e.g. Provision method calls).

type ConfigSettings

type ConfigSettings struct {
	// Whether to keep a copy of the active config on disk. Default is true.
	Persist *bool `json:"persist,omitempty"`
}

ConfigSettings configures the, uh, configuration... and management thereof.

type Constructor

type Constructor func() (Destructor, error)

Constructor is a function that returns a new value that can destruct itself when it is no longer needed.

type Context

type Context struct {
	context.Context
	// contains filtered or unexported fields
}

Context is a type which defines the lifetime of modules that are loaded and provides access to the parent configuration that spawned the modules which are loaded. It should be used with care and wrapped with derivation functions from the standard context package only if you don't need the Caddy specific features. These contexts are canceled when the lifetime of the modules loaded from it is over.

Use NewContext() to get a valid value (but most modules will not actually need to do this).

func NewContext

func NewContext(ctx Context) (Context, context.CancelFunc)

NewContext provides a new context derived from the given context ctx. Normally, you will not need to call this function unless you are loading modules which have a different lifespan than the ones for the context the module was provisioned with. Be sure to call the cancel func when the context is to be cleaned up so that modules which are loaded will be properly unloaded. See standard library context package's documentation.

func (Context) App

func (ctx Context) App(name string) (interface{}, error)

App returns the configured app named name. If no app with that name is currently configured, a new empty one will be instantiated. (The app module must still be registered.)

func (Context) LoadModule

func (ctx Context) LoadModule(structPointer interface{}, fieldName string) (interface{}, error)

LoadModule loads the Caddy module(s) from the specified field of the parent struct pointer and returns the loaded module(s). The struct pointer and its field name as a string are necessary so that reflection can be used to read the struct tag on the field to get the module namespace and inline module name key (if specified).

The field can be any one of the supported raw module types: json.RawMessage, []json.RawMessage, map[string]json.RawMessage, or []map[string]json.RawMessage. ModuleMap may be used in place of map[string]json.RawMessage. The return value's underlying type mirrors the input field's type:

json.RawMessage              => interface{}
[]json.RawMessage            => []interface{}
map[string]json.RawMessage   => map[string]interface{}
[]map[string]json.RawMessage => []map[string]interface{}

The field must have a "caddy" struct tag in this format:

caddy:"key1=val1 key2=val2"

To load modules, a "namespace" key is required. For example, to load modules in the "http.handlers" namespace, you'd put: `namespace=http.handlers` in the Caddy struct tag.

The module name must also be available. If the field type is a map or slice of maps, then key is assumed to be the module name if an "inline_key" is NOT specified in the caddy struct tag. In this case, the module name does NOT need to be specified in-line with the module itself.

If not a map, or if inline_key is non-empty, then the module name must be embedded into the values, which must be objects; then there must be a key in those objects where its associated value is the module name. This is called the "inline key", meaning the key containing the module's name that is defined inline with the module itself. You must specify the inline key in a struct tag, along with the namespace:

caddy:"namespace=http.handlers inline_key=handler"

This will look for a key/value pair like `"handler": "..."` in the json.RawMessage in order to know the module name.

To make use of the loaded module(s) (the return value), you will probably want to type-assert each interface{} value(s) to the types that are useful to you and store them on the same struct. Storing them on the same struct makes for easy garbage collection when your host module is no longer needed.

Loaded modules have already been provisioned and validated. Upon returning successfully, this method clears the json.RawMessage(s) in the field since the raw JSON is no longer needed, and this allows the GC to free up memory.

Example

Code:

// this whole first part is just setting up for the example;
// note the struct tags - very important; we specify inline_key
// because that is the only way to know the module name
var ctx Context
myStruct := &struct {
	// This godoc comment will appear in module documentation.
	GuestModuleRaw json.RawMessage `json:"guest_module,omitempty" caddy:"namespace=example inline_key=name"`

	// this is where the decoded module will be stored; in this
	// example, we pretend we need an io.Writer but it can be
	// any interface type that is useful to you
	guestModule io.Writer
}{
	GuestModuleRaw: json.RawMessage(`{"name":"module_name","foo":"bar"}`),
}

// if a guest module is provided, we can load it easily
if myStruct.GuestModuleRaw != nil {
	mod, err := ctx.LoadModule(myStruct, "GuestModuleRaw")
	if err != nil {
		// you'd want to actually handle the error here
		// return fmt.Errorf("loading guest module: %v", err)
	}
	// mod contains the loaded and provisioned module,
	// it is now ready for us to use
	myStruct.guestModule = mod.(io.Writer)
}

// use myStruct.guestModule from now on
Example (Array)

Code:

// this whole first part is just setting up for the example;
// note the struct tags - very important; we specify inline_key
// because that is the only way to know the module name
var ctx Context
myStruct := &struct {
	// This godoc comment will appear in module documentation.
	GuestModulesRaw []json.RawMessage `json:"guest_modules,omitempty" caddy:"namespace=example inline_key=name"`

	// this is where the decoded module will be stored; in this
	// example, we pretend we need an io.Writer but it can be
	// any interface type that is useful to you
	guestModules []io.Writer
}{
	GuestModulesRaw: []json.RawMessage{
		json.RawMessage(`{"name":"module1_name","foo":"bar1"}`),
		json.RawMessage(`{"name":"module2_name","foo":"bar2"}`),
	},
}

// since our input is []json.RawMessage, the output will be []interface{}
mods, err := ctx.LoadModule(myStruct, "GuestModulesRaw")
if err != nil {
	// you'd want to actually handle the error here
	// return fmt.Errorf("loading guest modules: %v", err)
}
for _, mod := range mods.([]interface{}) {
	myStruct.guestModules = append(myStruct.guestModules, mod.(io.Writer))
}

// use myStruct.guestModules from now on
Example (Map)

Code:

// this whole first part is just setting up for the example;
// note the struct tags - very important; we don't specify
// inline_key because the map key is the module name
var ctx Context
myStruct := &struct {
	// This godoc comment will appear in module documentation.
	GuestModulesRaw ModuleMap `json:"guest_modules,omitempty" caddy:"namespace=example"`

	// this is where the decoded module will be stored; in this
	// example, we pretend we need an io.Writer but it can be
	// any interface type that is useful to you
	guestModules map[string]io.Writer
}{
	GuestModulesRaw: ModuleMap{
		"module1_name": json.RawMessage(`{"foo":"bar1"}`),
		"module2_name": json.RawMessage(`{"foo":"bar2"}`),
	},
}

// since our input is map[string]json.RawMessage, the output will be map[string]interface{}
mods, err := ctx.LoadModule(myStruct, "GuestModulesRaw")
if err != nil {
	// you'd want to actually handle the error here
	// return fmt.Errorf("loading guest modules: %v", err)
}
for modName, mod := range mods.(map[string]interface{}) {
	myStruct.guestModules[modName] = mod.(io.Writer)
}

// use myStruct.guestModules from now on

func (Context) LoadModuleByID

func (ctx Context) LoadModuleByID(id string, rawMsg json.RawMessage) (interface{}, error)

LoadModuleByID decodes rawMsg into a new instance of mod and returns the value. If mod.New is nil, an error is returned. If the module implements Validator or Provisioner interfaces, those methods are invoked to ensure the module is fully configured and valid before being used.

This is a lower-level method and will usually not be called directly by most modules. However, this method is useful when dynamically loading/unloading modules in their own context, like from embedded scripts, etc.

func (Context) Logger

func (ctx Context) Logger(mod Module) *zap.Logger

Logger returns a logger that can be used by mod.

func (*Context) OnCancel

func (ctx *Context) OnCancel(f func())

OnCancel executes f when ctx is canceled.

func (Context) Storage

func (ctx Context) Storage() certmagic.Storage

Storage returns the configured Caddy storage implementation.

type CtxKey

type CtxKey string

CtxKey is a value type for use with context.WithValue.

const ReplacerCtxKey CtxKey = "replacer"

ReplacerCtxKey is the context key for a replacer.

type CustomLog

type CustomLog struct {
	// The writer defines where log entries are emitted.
	WriterRaw json.RawMessage `json:"writer,omitempty" caddy:"namespace=caddy.logging.writers inline_key=output"`

	// The encoder is how the log entries are formatted or encoded.
	EncoderRaw json.RawMessage `json:"encoder,omitempty" caddy:"namespace=caddy.logging.encoders inline_key=format"`

	// Level is the minimum level to emit, and is inclusive.
	// Possible levels: DEBUG, INFO, WARN, ERROR, PANIC, and FATAL
	Level string `json:"level,omitempty"`

	// Sampling configures log entry sampling. If enabled,
	// only some log entries will be emitted. This is useful
	// for improving performance on extremely high-pressure
	// servers.
	Sampling *LogSampling `json:"sampling,omitempty"`

	// Include defines the names of loggers to emit in this
	// log. For example, to include only logs emitted by the
	// admin API, you would include "admin.api".
	Include []string `json:"include,omitempty"`

	// Exclude defines the names of loggers that should be
	// skipped by this log. For example, to exclude only
	// HTTP access logs, you would exclude "http.log.access".
	Exclude []string `json:"exclude,omitempty"`
	// contains filtered or unexported fields
}

CustomLog represents a custom logger configuration.

By default, a log will emit all log entries. Some entries will be skipped if sampling is enabled. Further, the Include and Exclude parameters define which loggers (by name) are allowed or rejected from emitting in this log. If both Include and Exclude are populated, their values must be mutually exclusive, and longer namespaces have priority. If neither are populated, all logs are emitted.

type Destructor

type Destructor interface {
	Destruct() error
}

Destructor is a value that can clean itself up when it is deallocated.

type DiscardWriter

type DiscardWriter struct{}

DiscardWriter discards all writes.

func (DiscardWriter) CaddyModule

func (DiscardWriter) CaddyModule() ModuleInfo

CaddyModule returns the Caddy module information.

func (DiscardWriter) OpenWriter

func (DiscardWriter) OpenWriter() (io.WriteCloser, error)

OpenWriter returns ioutil.Discard that can't be closed.

func (DiscardWriter) String

func (DiscardWriter) String() string

func (DiscardWriter) WriterKey

func (DiscardWriter) WriterKey() string

WriterKey returns a unique key representing discard.

type Duration

type Duration time.Duration

Duration can be an integer or a string. An integer is interpreted as nanoseconds. If a string, it is a Go time.Duration value such as `300ms`, `1.5h`, or `2h45m`; valid units are `ns`, `us`/`µs`, `ms`, `s`, `m`, and `h`.

func (*Duration) UnmarshalJSON

func (d *Duration) UnmarshalJSON(b []byte) error

UnmarshalJSON satisfies json.Unmarshaler.

type ListenerWrapper

type ListenerWrapper interface {
	WrapListener(net.Listener) net.Listener
}

ListenerWrapper is a type that wraps a listener so it can modify the input listener's methods. Modules that implement this interface are found in the caddy.listeners namespace. Usually, to wrap a listener, you will define your own struct type that embeds the input listener, then implement your own methods that you want to wrap, calling the underlying listener's methods where appropriate.

type LogSampling

type LogSampling struct {
	// The window over which to conduct sampling.
	Interval time.Duration `json:"interval,omitempty"`

	// Log this many entries within a given level and
	// message for each interval.
	First int `json:"first,omitempty"`

	// If more entries with the same level and message
	// are seen during the same interval, keep one in
	// this many entries until the end of the interval.
	Thereafter int `json:"thereafter,omitempty"`
}

LogSampling configures log entry sampling.

type Logging

type Logging struct {
	// Sink is the destination for all unstructured logs emitted
	// from Go's standard library logger. These logs are common
	// in dependencies that are not designed specifically for use
	// in Caddy. Because it is global and unstructured, the sink
	// lacks most advanced features and customizations.
	Sink *StandardLibLog `json:"sink,omitempty"`

	// Logs are your logs, keyed by an arbitrary name of your
	// choosing. The default log can be customized by defining
	// a log called "default". You can further define other logs
	// and filter what kinds of entries they accept.
	Logs map[string]*CustomLog `json:"logs,omitempty"`
	// contains filtered or unexported fields
}

Logging facilitates logging within Caddy.

By default, all logs at INFO level and higher are written to standard error ("stderr" writer) in a human-readable format ("console" encoder). The default log is called "default" and you can customize it. You can also define additional logs.

All defined logs accept all log entries by default, but you can filter by level and module/logger names. A logger's name is the same as the module's name, but a module may append to logger names for more specificity. For example, you can filter logs emitted only by HTTP handlers using the name "http.handlers", because all HTTP handler module names have that prefix.

Caddy logs (except the sink) are mostly zero-allocation, so they are very high-performing in terms of memory and CPU time. Enabling sampling can further increase throughput on extremely high-load servers.

func (*Logging) Logger

func (logging *Logging) Logger(mod Module) *zap.Logger

Logger returns a logger that is ready for the module to use.

type Module

type Module interface {
	// This method indicates that the type is a Caddy
	// module. The returned ModuleInfo must have both
	// a name and a constructor function. This method
	// must not have any side-effects.
	CaddyModule() ModuleInfo
}

Module is a type that is used as a Caddy module. In addition to this interface, most modules will implement some interface expected by their host module in order to be useful. To learn which interface(s) to implement, see the documentation for the host module. At a bare minimum, this interface, when implemented, only provides the module's ID and constructor function.

Modules will often implement additional interfaces including Provisioner, Validator, and CleanerUpper. If a module implements these interfaces, their methods are called during the module's lifespan.

When a module is loaded by a host module, the following happens: 1) ModuleInfo.New() is called to get a new instance of the module. 2) The module's configuration is unmarshaled into that instance. 3) If the module is a Provisioner, the Provision() method is called. 4) If the module is a Validator, the Validate() method is called. 5) The module will probably be type-asserted from interface{} to some other, more useful interface expected by the host module. For example, HTTP handler modules are type-asserted as caddyhttp.MiddlewareHandler values. 6) When a module's containing Context is canceled, if it is a CleanerUpper, its Cleanup() method is called.

type ModuleID

type ModuleID string

ModuleID is a string that uniquely identifies a Caddy module. A module ID is lightly structured. It consists of dot-separated labels which form a simple hierarchy from left to right. The last label is the module name, and the labels before that constitute the namespace (or scope).

Thus, a module ID has the form: <namespace>.<name>

An ID with no dot has the empty namespace, which is appropriate for app modules (these are "top-level" modules that Caddy core loads and runs).

Module IDs should be lowercase and use underscores (_) instead of spaces.

Examples of valid IDs: - http - http.handlers.file_server - caddy.logging.encoders.json

func (ModuleID) Name

func (id ModuleID) Name() string

Name returns the Name (last element) of a module ID.

func (ModuleID) Namespace

func (id ModuleID) Namespace() string

Namespace returns the namespace (or scope) portion of a module ID, which is all but the last label of the ID. If the ID has only one label, then the namespace is empty.

type ModuleInfo

type ModuleInfo struct {
	// ID is the "full name" of the module. It
	// must be unique and properly namespaced.
	ID ModuleID

	// New returns a pointer to a new, empty
	// instance of the module's type. This
	// function must not have any side-effects.
	New func() Module
}

ModuleInfo represents a registered Caddy module.

func GetModule

func GetModule(name string) (ModuleInfo, error)

GetModule returns module information from its ID (full name).

func GetModules

func GetModules(scope string) []ModuleInfo

GetModules returns all modules in the given scope/namespace. For example, a scope of "foo" returns modules named "foo.bar", "foo.loo", but not "bar", "foo.bar.loo", etc. An empty scope returns top-level modules, for example "foo" or "bar". Partial scopes are not matched (i.e. scope "foo.ba" does not match name "foo.bar").

Because modules are registered to a map under the hood, the returned slice will be sorted to keep it deterministic.

func (ModuleInfo) String

func (mi ModuleInfo) String() string

type ModuleMap

type ModuleMap map[string]json.RawMessage

ModuleMap is a map that can contain multiple modules, where the map key is the module's name. (The namespace is usually read from an associated field's struct tag.) Because the module's name is given as the key in a module map, the name does not have to be given in the json.RawMessage.

type ParsedAddress

type ParsedAddress struct {
	Network   string
	Host      string
	StartPort uint
	EndPort   uint
}

ParsedAddress contains the individual components for a parsed network address of the form accepted by ParseNetworkAddress(). Network should be a network value accepted by Go's net package. Port ranges are given by [StartPort, EndPort].

func ParseNetworkAddress

func ParseNetworkAddress(addr string) (ParsedAddress, error)

ParseNetworkAddress parses addr into its individual components. The input string is expected to be of the form "network/host:port-range" where any part is optional. The default network, if unspecified, is tcp. Port ranges are inclusive.

Network addresses are distinct from URLs and do not use URL syntax.

func (ParsedAddress) IsUnixNetwork

func (pa ParsedAddress) IsUnixNetwork() bool

IsUnixNetwork returns true if pa.Network is unix, unixgram, or unixpacket.

func (ParsedAddress) JoinHostPort

func (pa ParsedAddress) JoinHostPort(offset uint) string

JoinHostPort is like net.JoinHostPort, but where the port is StartPort + offset.

func (ParsedAddress) PortRangeSize

func (pa ParsedAddress) PortRangeSize() uint

PortRangeSize returns how many ports are in pa's port range. Port ranges are inclusive, so the size is the difference of start and end ports plus one.

func (ParsedAddress) String

func (pa ParsedAddress) String() string

String reconstructs the address string to the form expected by ParseNetworkAddress().

type Provisioner

type Provisioner interface {
	Provision(Context) error
}

Provisioner is implemented by modules which may need to perform some additional "setup" steps immediately after being loaded. Provisioning should be fast (imperceptible running time). If any side-effects result in the execution of this function (e.g. creating global state, any other allocations which require garbage collection, opening files, starting goroutines etc.), be sure to clean up properly by implementing the CleanerUpper interface to avoid leaking resources.

type ReplacementFunc

type ReplacementFunc func(variable, val string) (string, error)

ReplacementFunc is a function that is called when a replacement is being performed. It receives the variable (i.e. placeholder name) and the value that will be the replacement, and returns the value that will actually be the replacement, or an error. Note that errors are sometimes ignored by replacers.

type Replacer

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

Replacer can replace values in strings. A default/empty Replacer is not valid; use NewReplacer to make one.

func NewReplacer

func NewReplacer() *Replacer

NewReplacer returns a new Replacer.

func (*Replacer) Delete

func (r *Replacer) Delete(variable string)

Delete removes a variable with a static value that was created using Set.

func (*Replacer) Get

func (r *Replacer) Get(variable string) (string, bool)

Get gets a value from the replacer. It returns the value and whether the variable was known.

func (*Replacer) Map

func (r *Replacer) Map(mapFunc ReplacerFunc)

Map adds mapFunc to the list of value providers. mapFunc will be executed only at replace-time.

func (*Replacer) ReplaceAll

func (r *Replacer) ReplaceAll(input, empty string) string

ReplaceAll efficiently replaces placeholders in input with their values. All placeholders are replaced in the output whether they are recognized or not. Values that are empty string will be substituted with empty.

func (*Replacer) ReplaceFunc

func (r *Replacer) ReplaceFunc(input string, f ReplacementFunc) (string, error)

ReplaceFunc calls ReplaceAll efficiently replaces placeholders in input with their values. All placeholders are replaced in the output whether they are recognized or not. Values that are empty string will be substituted with empty.

func (*Replacer) ReplaceKnown

func (r *Replacer) ReplaceKnown(input, empty string) string

ReplaceKnown is like ReplaceAll but only replaces placeholders that are known (recognized). Unrecognized placeholders will remain in the output.

func (*Replacer) ReplaceOrErr

func (r *Replacer) ReplaceOrErr(input string, errOnEmpty, errOnUnknown bool) (string, error)

ReplaceOrErr is like ReplaceAll, but any placeholders that are empty or not recognized will cause an error to be returned.

func (*Replacer) Set

func (r *Replacer) Set(variable, value string)

Set sets a custom variable to a static value.

type ReplacerFunc

type ReplacerFunc func(key string) (val string, ok bool)

ReplacerFunc is a function that returns a replacement for the given key along with true if the function is able to service that key (even if the value is blank). If the function does not recognize the key, false should be returned.

type StandardLibLog

type StandardLibLog struct {
	// The module that writes out log entries for the sink.
	WriterRaw json.RawMessage `json:"writer,omitempty" caddy:"namespace=caddy.logging.writers inline_key=output"`
	// contains filtered or unexported fields
}

StandardLibLog configures the default Go standard library global logger in the log package. This is necessary because module dependencies which are not built specifically for Caddy will use the standard logger. This is also known as the "sink" logger.

type StderrWriter

type StderrWriter struct{}

StderrWriter writes logs to standard error.

func (StderrWriter) CaddyModule

func (StderrWriter) CaddyModule() ModuleInfo

CaddyModule returns the Caddy module information.

func (StderrWriter) OpenWriter

func (StderrWriter) OpenWriter() (io.WriteCloser, error)

OpenWriter returns os.Stderr that can't be closed.

func (StderrWriter) String

func (StderrWriter) String() string

func (StderrWriter) WriterKey

func (StderrWriter) WriterKey() string

WriterKey returns a unique key representing stderr.

type StdoutWriter

type StdoutWriter struct{}

StdoutWriter writes logs to standard out.

func (StdoutWriter) CaddyModule

func (StdoutWriter) CaddyModule() ModuleInfo

CaddyModule returns the Caddy module information.

func (StdoutWriter) OpenWriter

func (StdoutWriter) OpenWriter() (io.WriteCloser, error)

OpenWriter returns os.Stdout that can't be closed.

func (StdoutWriter) String

func (StdoutWriter) String() string

func (StdoutWriter) WriterKey

func (StdoutWriter) WriterKey() string

WriterKey returns a unique key representing stdout.

type StorageConverter

type StorageConverter interface {
	CertMagicStorage() (certmagic.Storage, error)
}

StorageConverter is a type that can convert itself to a valid, usable certmagic.Storage value. (The value might be short-lived.) This interface allows us to adapt any CertMagic storage implementation into a consistent API for Caddy configuration.

type UsagePool

type UsagePool struct {
	sync.RWMutex
	// contains filtered or unexported fields
}

UsagePool is a thread-safe map that pools values based on usage (reference counting). Values are only inserted if they do not already exist. There are two ways to add values to the pool:

1) LoadOrStore will increment usage and store the
   value immediately if it does not already exist.
2) LoadOrNew will atomically check for existence
   and construct the value immediately if it does
   not already exist, or increment the usage
   otherwise, then store that value in the pool.
   When the constructed value is finally deleted
   from the pool (when its usage reaches 0), it
   will be cleaned up by calling Destruct().

The use of LoadOrNew allows values to be created and reused and finally cleaned up only once, even though they may have many references throughout their lifespan. This is helpful, for example, when sharing thread-safe io.Writers that you only want to open and close once.

There is no way to overwrite existing keys in the pool without first deleting it as many times as it was stored. Deleting too many times will panic.

The implementation does not use a sync.Pool because UsagePool needs additional atomicity to run the constructor functions when creating a new value when LoadOrNew is used. (We could probably use sync.Pool but we'd still have to layer our own additional locks on top.)

An empty UsagePool is NOT safe to use; always call NewUsagePool() to make a new one.

func NewUsagePool

func NewUsagePool() *UsagePool

NewUsagePool returns a new usage pool that is ready to use.

func (*UsagePool) Delete

func (up *UsagePool) Delete(key interface{}) (deleted bool, err error)

Delete decrements the usage count for key and removes the value from the underlying map if the usage is 0. It returns true if the usage count reached 0 and the value was deleted. It panics if the usage count drops below 0; always call Delete precisely as many times as LoadOrStore.

func (*UsagePool) LoadOrNew

func (up *UsagePool) LoadOrNew(key interface{}, construct Constructor) (value interface{}, loaded bool, err error)

LoadOrNew loads the value associated with key from the pool if it already exists. If the key doesn't exist, it will call construct to create a new value and then stores that in the pool. An error is only returned if the constructor returns an error. The loaded or constructed value is returned. The loaded return value is true if the value already existed and was loaded, or false if it was newly constructed.

func (*UsagePool) LoadOrStore

func (up *UsagePool) LoadOrStore(key, val interface{}) (value interface{}, loaded bool)

LoadOrStore loads the value associated with key from the pool if it already exists, or stores it if it does not exist. It returns the value that was either loaded or stored, and true if the value already existed and was

func (*UsagePool) Range

func (up *UsagePool) Range(f func(key, value interface{}) bool)

Range iterates the pool similarly to how sync.Map.Range() does: it calls f for every key in the pool, and if f returns false, iteration is stopped. Ranging does not affect usage counts.

This method is somewhat naive and acquires a read lock on the entire pool during iteration, so do your best to make f() really fast, m'kay?

type Validator

type Validator interface {
	Validate() error
}

Validator is implemented by modules which can verify that their configurations are valid. This method will be called after Provision() (if implemented). Validation should always be fast (imperceptible running time) and an error must be returned if the module's configuration is invalid.

type WriterOpener

type WriterOpener interface {
	fmt.Stringer

	// WriterKey is a string that uniquely identifies this
	// writer configuration. It is not shown to humans.
	WriterKey() string

	// OpenWriter opens a log for writing. The writer
	// should be safe for concurrent use but need not
	// be synchronous.
	OpenWriter() (io.WriteCloser, error)
}

WriterOpener is a module that can open a log writer. It can return a human-readable string representation of itself so that operators can understand where the logs are going.