caddy/plugins.go at master · cluo/caddy · GitHub

Repository navigation

History

100

101

102

103

104

105

106

107

108

109

110

111

112

113

114

115

116

117

118

119

120

121

122

123

124

125

126

127

128

129

130

131

132

133

134

135

136

137

138

139

140

141

142

143

144

145

146

147

148

149

150

151

152

153

154

155

156

157

158

159

160

161

162

163

164

165

166

167

168

169

170

171

172

173

174

175

176

177

178

179

180

181

182

183

184

185

186

187

188

189

190

191

192

193

194

195

196

197

198

199

200

201

202

203

204

205

206

207

208

209

210

211

212

213

214

215

216

217

218

219

220

221

222

223

224

225

226

227

228

229

230

231

232

233

234

235

236

237

238

239

240

241

242

243

244

245

246

247

248

249

250

251

252

253

254

255

256

257

258

259

260

261

262

263

264

265

266

267

268

269

270

271

272

273

274

275

276

277

278

279

280

281

282

283

284

285

286

287

288

289

290

291

292

293

294

295

296

297

298

299

300

301

302

303

304

305

306

307

308

309

310

311

312

313

314

315

316

317

318

319

320

321

322

323

324

325

326

327

328

329

330

331

332

333

334

335

336

337

338

339

340

341

342

343

344

345

346

347

348

349

350

351

352

353

354

355

356

357

358

359

360

361

362

363

364

365

366

367

368

369

370

371

372

373

374

375

376

377

378

379

package caddy

import (

"fmt"

"log"

"net"

"sort"

"github.com/mholt/caddy/caddyfile"

)

// These are all the registered plugins.

var (

// serverTypes is a map of registered server types.

serverTypes = make(map[string]ServerType)

// plugins is a map of server type to map of plugin name to

// Plugin. These are the "general" plugins that may or may

// not be associated with a specific server type. If it's

// applicable to multiple server types or the server type is

// irrelevant, the key is empty string (""). But all plugins

// must have a name.

plugins = make(map[string]map[string]Plugin)

// eventHooks is a map of hook name to Hook. All hooks plugins

// must have a name.

eventHooks = make(map[string]EventHook)

// parsingCallbacks maps server type to map of directive

// to list of callback functions. These aren't really

// plugins on their own, but are often registered from

// plugins.

parsingCallbacks = make(map[string]map[string][]ParsingCallback)

// caddyfileLoaders is the list of all Caddyfile loaders

// in registration order.

caddyfileLoaders []caddyfileLoader

)

// DescribePlugins returns a string describing the registered plugins.

func DescribePlugins() string {

str := "Server types:\n"

for name := range serverTypes {

str += " " + name + "\n"

}

// List the loaders in registration order

str += "\nCaddyfile loaders:\n"

for _, loader := range caddyfileLoaders {

str += " " + loader.name + "\n"

}

if defaultCaddyfileLoader.name != "" {

str += " " + defaultCaddyfileLoader.name + "\n"

}

if len(eventHooks) > 0 {

// List the event hook plugins

str += "\nEvent hook plugins:\n"

for hookPlugin := range eventHooks {

str += " hook." + hookPlugin + "\n"

}

// Let's alphabetize the rest of these...

var others []string

for stype, stypePlugins := range plugins {

for name := range stypePlugins {

var s string

if stype != "" {

s = stype + "."

}

s += name

others = append(others, s)

}

sort.Strings(others)

str += "\nOther plugins:\n"

for _, name := range others {

str += " " + name + "\n"

}

return str

}

// ValidDirectives returns the list of all directives that are

// recognized for the server type serverType. However, not all

// directives may be installed. This makes it possible to give

// more helpful error messages, like "did you mean ..." or

// "maybe you need to plug in ...".

func ValidDirectives(serverType string) []string {

stype, err := getServerType(serverType)

if err != nil {

return nil

}

return stype.Directives()

}

// ServerListener pairs a server to its listener and/or packetconn.

type ServerListener struct {

server Server

listener net.Listener

packet net.PacketConn

}

// LocalAddr returns the local network address of the packetconn. It returns

// nil when it is not set.

func (s ServerListener) LocalAddr() net.Addr {

if s.packet == nil {

return nil

}

return s.packet.LocalAddr()

}

// Addr returns the listener's network address. It returns nil when it is

// not set.

func (s ServerListener) Addr() net.Addr {

if s.listener == nil {

return nil

}

return s.listener.Addr()

}

// Context is a type which carries a server type through

// the load and setup phase; it maintains the state

// between loading the Caddyfile, then executing its

// directives, then making the servers for Caddy to

// manage. Typically, such state involves configuration

// structs, etc.

type Context interface {

// Called after the Caddyfile is parsed into server

// blocks but before the directives are executed,

// this method gives you an opportunity to inspect

// the server blocks and prepare for the execution

// of directives. Return the server blocks (which

// you may modify, if desired) and an error, if any.

// The first argument is the name or path to the

// configuration file (Caddyfile).

// This function can be a no-op and simply return its

// input if there is nothing to do here.

InspectServerBlocks(string, []caddyfile.ServerBlock) ([]caddyfile.ServerBlock, error)

// This is what Caddy calls to make server instances.

// By this time, all directives have been executed and,

// presumably, the context has enough state to produce

// server instances for Caddy to start.

MakeServers() ([]Server, error)

}

// RegisterServerType registers a server type srv by its

// name, typeName.

func RegisterServerType(typeName string, srv ServerType) {

if _, ok := serverTypes[typeName]; ok {

panic("server type already registered")

}

serverTypes[typeName] = srv

}

// ServerType contains information about a server type.

type ServerType struct {

// Function that returns the list of directives, in

// execution order, that are valid for this server

// type. Directives should be one word if possible

// and lower-cased.

Directives func() []string

// DefaultInput returns a default config input if none

// is otherwise loaded. This is optional, but highly

// recommended, otherwise a blank Caddyfile will be

// used.

DefaultInput func() Input

// The function that produces a new server type context.

// This will be called when a new Caddyfile is being

// loaded, parsed, and executed independently of any

// startup phases before this one. It's a way to keep

// each set of server instances separate and to reduce

// the amount of global state you need.

NewContext func() Context

}

// Plugin is a type which holds information about a plugin.

type Plugin struct {

// ServerType is the type of server this plugin is for.

// Can be empty if not applicable, or if the plugin

// can associate with any server type.

ServerType string

// Action is the plugin's setup function, if associated

// with a directive in the Caddyfile.

Action SetupFunc

}

// RegisterPlugin plugs in plugin. All plugins should register

// themselves, even if they do not perform an action associated

// with a directive. It is important for the process to know

// which plugins are available.

// The plugin MUST have a name: lower case and one word.

// If this plugin has an action, it must be the name of

// the directive that invokes it. A name is always required

// and must be unique for the server type.

func RegisterPlugin(name string, plugin Plugin) {

if name == "" {

panic("plugin must have a name")

}

if _, ok := plugins[plugin.ServerType]; !ok {

plugins[plugin.ServerType] = make(map[string]Plugin)

}

if _, dup := plugins[plugin.ServerType][name]; dup {

panic("plugin named " + name + " already registered for server type " + plugin.ServerType)

}

plugins[plugin.ServerType][name] = plugin

}

// EventName represents the name of an event used with event hooks.

type EventName string

// Define the event names for the startup and shutdown events

const (

StartupEvent EventName = "startup"

ShutdownEvent EventName = "shutdown"

)

// EventHook is a type which holds information about a startup hook plugin.

type EventHook func(eventType EventName) error

// RegisterEventHook plugs in hook. All the hooks should register themselves

// and they must have a name.

func RegisterEventHook(name string, hook EventHook) {

if name == "" {

panic("event hook must have a name")

}

if _, dup := eventHooks[name]; dup {

panic("hook named " + name + " already registered")

}

eventHooks[name] = hook

}

// EmitEvent executes the different hooks passing the EventType as an

// argument. This is a blocking function. Hook developers should

// use 'go' keyword if they don't want to block Caddy.

func EmitEvent(event EventName) {

for name, hook := range eventHooks {

err := hook(event)

if err != nil {

log.Printf("error on '%s' hook: %v", name, err)

}

// ParsingCallback is a function that is called after

// a directive's setup functions have been executed

// for all the server blocks.

type ParsingCallback func(Context) error

// RegisterParsingCallback registers callback to be called after

// executing the directive afterDir for server type serverType.

func RegisterParsingCallback(serverType, afterDir string, callback ParsingCallback) {

if _, ok := parsingCallbacks[serverType]; !ok {

parsingCallbacks[serverType] = make(map[string][]ParsingCallback)

}

parsingCallbacks[serverType][afterDir] = append(parsingCallbacks[serverType][afterDir], callback)

}

// SetupFunc is used to set up a plugin, or in other words,

// execute a directive. It will be called once per key for

// each server block it appears in.

type SetupFunc func(c *Controller) error

// DirectiveAction gets the action for directive dir of

// server type serverType.

func DirectiveAction(serverType, dir string) (SetupFunc, error) {

if stypePlugins, ok := plugins[serverType]; ok {

if plugin, ok := stypePlugins[dir]; ok {

return plugin.Action, nil

}

if genericPlugins, ok := plugins[""]; ok {

if plugin, ok := genericPlugins[dir]; ok {

return plugin.Action, nil

}

return nil, fmt.Errorf("no action found for directive '%s' with server type '%s' (missing a plugin?)",

dir, serverType)

}

// Loader is a type that can load a Caddyfile.

// It is passed the name of the server type.

// It returns an error only if something went

// wrong, not simply if there is no Caddyfile

// for this loader to load.

// A Loader should only load the Caddyfile if

// a certain condition or requirement is met,

// as returning a non-nil Input value along with

// another Loader will result in an error.

// In other words, loading the Caddyfile must

// be deliberate & deterministic, not haphazard.

// The exception is the default Caddyfile loader,

// which will be called only if no other Caddyfile

// loaders return a non-nil Input. The default

// loader may always return an Input value.

type Loader interface {

Load(serverType string) (Input, error)

}

// LoaderFunc is a convenience type similar to http.HandlerFunc

// that allows you to use a plain function as a Load() method.

type LoaderFunc func(serverType string) (Input, error)

// Load loads a Caddyfile.

func (lf LoaderFunc) Load(serverType string) (Input, error) {

return lf(serverType)

}

// RegisterCaddyfileLoader registers loader named name.

func RegisterCaddyfileLoader(name string, loader Loader) {

caddyfileLoaders = append(caddyfileLoaders, caddyfileLoader{name: name, loader: loader})

}

// SetDefaultCaddyfileLoader registers loader by name

// as the default Caddyfile loader if no others produce

// a Caddyfile. If another Caddyfile loader has already

// been set as the default, this replaces it.

// Do not call RegisterCaddyfileLoader on the same

// loader; that would be redundant.

func SetDefaultCaddyfileLoader(name string, loader Loader) {

defaultCaddyfileLoader = caddyfileLoader{name: name, loader: loader}

}

// loadCaddyfileInput iterates the registered Caddyfile loaders

// and, if needed, calls the default loader, to load a Caddyfile.

// It is an error if any of the loaders return an error or if

// more than one loader returns a Caddyfile.

func loadCaddyfileInput(serverType string) (Input, error) {

var loadedBy string

var caddyfileToUse Input

for _, l := range caddyfileLoaders {

cdyfile, err := l.loader.Load(serverType)

if err != nil {

return nil, fmt.Errorf("loading Caddyfile via %s: %v", l.name, err)

}

if cdyfile != nil {

if caddyfileToUse != nil {

return nil, fmt.Errorf("Caddyfile loaded multiple times; first by %s, then by %s", loadedBy, l.name)

}

loaderUsed = l

caddyfileToUse = cdyfile

loadedBy = l.name

}

if caddyfileToUse == nil && defaultCaddyfileLoader.loader != nil {

cdyfile, err := defaultCaddyfileLoader.loader.Load(serverType)

if err != nil {

return nil, err

}

if cdyfile != nil {

loaderUsed = defaultCaddyfileLoader

caddyfileToUse = cdyfile

}

return caddyfileToUse, nil

}

// caddyfileLoader pairs the name of a loader to the loader.

type caddyfileLoader struct {

name string

loader Loader

}

var (

defaultCaddyfileLoader caddyfileLoader // the default loader if all else fail

loaderUsed caddyfileLoader // the loader that was used (relevant for reloads)

)

caddy/plugins.go at master · cluo/caddy · GitHub

Repository navigation

Expand file tree

Breadcrumbs

plugins.go

Latest commit

History

Breadcrumbs

plugins.go

File metadata and controls