Serge Bazanski | cc25bdf | 2018-10-25 14:02:58 +0200 | [diff] [blame] | 1 | /* |
| 2 | * |
| 3 | * Copyright 2018 gRPC authors. |
| 4 | * |
| 5 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 6 | * you may not use this file except in compliance with the License. |
| 7 | * You may obtain a copy of the License at |
| 8 | * |
| 9 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 10 | * |
| 11 | * Unless required by applicable law or agreed to in writing, software |
| 12 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 13 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 14 | * See the License for the specific language governing permissions and |
| 15 | * limitations under the License. |
| 16 | * |
| 17 | */ |
| 18 | |
| 19 | package grpc |
| 20 | |
| 21 | import ( |
| 22 | "fmt" |
| 23 | "net" |
| 24 | "time" |
| 25 | |
| 26 | "golang.org/x/net/context" |
| 27 | "google.golang.org/grpc/balancer" |
| 28 | "google.golang.org/grpc/credentials" |
| 29 | "google.golang.org/grpc/internal" |
| 30 | "google.golang.org/grpc/internal/backoff" |
| 31 | "google.golang.org/grpc/internal/envconfig" |
| 32 | "google.golang.org/grpc/internal/transport" |
| 33 | "google.golang.org/grpc/keepalive" |
| 34 | "google.golang.org/grpc/resolver" |
| 35 | "google.golang.org/grpc/stats" |
| 36 | ) |
| 37 | |
| 38 | // dialOptions configure a Dial call. dialOptions are set by the DialOption |
| 39 | // values passed to Dial. |
| 40 | type dialOptions struct { |
| 41 | unaryInt UnaryClientInterceptor |
| 42 | streamInt StreamClientInterceptor |
| 43 | cp Compressor |
| 44 | dc Decompressor |
| 45 | bs backoff.Strategy |
| 46 | block bool |
| 47 | insecure bool |
| 48 | timeout time.Duration |
| 49 | scChan <-chan ServiceConfig |
| 50 | authority string |
| 51 | copts transport.ConnectOptions |
| 52 | callOptions []CallOption |
| 53 | // This is used by v1 balancer dial option WithBalancer to support v1 |
| 54 | // balancer, and also by WithBalancerName dial option. |
| 55 | balancerBuilder balancer.Builder |
| 56 | // This is to support grpclb. |
| 57 | resolverBuilder resolver.Builder |
| 58 | waitForHandshake bool |
| 59 | channelzParentID int64 |
| 60 | disableServiceConfig bool |
| 61 | disableRetry bool |
| 62 | } |
| 63 | |
| 64 | // DialOption configures how we set up the connection. |
| 65 | type DialOption interface { |
| 66 | apply(*dialOptions) |
| 67 | } |
| 68 | |
| 69 | // EmptyDialOption does not alter the dial configuration. It can be embedded in |
| 70 | // another structure to build custom dial options. |
| 71 | // |
| 72 | // This API is EXPERIMENTAL. |
| 73 | type EmptyDialOption struct{} |
| 74 | |
| 75 | func (EmptyDialOption) apply(*dialOptions) {} |
| 76 | |
| 77 | // funcDialOption wraps a function that modifies dialOptions into an |
| 78 | // implementation of the DialOption interface. |
| 79 | type funcDialOption struct { |
| 80 | f func(*dialOptions) |
| 81 | } |
| 82 | |
| 83 | func (fdo *funcDialOption) apply(do *dialOptions) { |
| 84 | fdo.f(do) |
| 85 | } |
| 86 | |
| 87 | func newFuncDialOption(f func(*dialOptions)) *funcDialOption { |
| 88 | return &funcDialOption{ |
| 89 | f: f, |
| 90 | } |
| 91 | } |
| 92 | |
| 93 | // WithWaitForHandshake blocks until the initial settings frame is received from |
| 94 | // the server before assigning RPCs to the connection. Experimental API. |
| 95 | func WithWaitForHandshake() DialOption { |
| 96 | return newFuncDialOption(func(o *dialOptions) { |
| 97 | o.waitForHandshake = true |
| 98 | }) |
| 99 | } |
| 100 | |
| 101 | // WithWriteBufferSize determines how much data can be batched before doing a |
| 102 | // write on the wire. The corresponding memory allocation for this buffer will |
| 103 | // be twice the size to keep syscalls low. The default value for this buffer is |
| 104 | // 32KB. |
| 105 | // |
| 106 | // Zero will disable the write buffer such that each write will be on underlying |
| 107 | // connection. Note: A Send call may not directly translate to a write. |
| 108 | func WithWriteBufferSize(s int) DialOption { |
| 109 | return newFuncDialOption(func(o *dialOptions) { |
| 110 | o.copts.WriteBufferSize = s |
| 111 | }) |
| 112 | } |
| 113 | |
| 114 | // WithReadBufferSize lets you set the size of read buffer, this determines how |
| 115 | // much data can be read at most for each read syscall. |
| 116 | // |
| 117 | // The default value for this buffer is 32KB. Zero will disable read buffer for |
| 118 | // a connection so data framer can access the underlying conn directly. |
| 119 | func WithReadBufferSize(s int) DialOption { |
| 120 | return newFuncDialOption(func(o *dialOptions) { |
| 121 | o.copts.ReadBufferSize = s |
| 122 | }) |
| 123 | } |
| 124 | |
| 125 | // WithInitialWindowSize returns a DialOption which sets the value for initial |
| 126 | // window size on a stream. The lower bound for window size is 64K and any value |
| 127 | // smaller than that will be ignored. |
| 128 | func WithInitialWindowSize(s int32) DialOption { |
| 129 | return newFuncDialOption(func(o *dialOptions) { |
| 130 | o.copts.InitialWindowSize = s |
| 131 | }) |
| 132 | } |
| 133 | |
| 134 | // WithInitialConnWindowSize returns a DialOption which sets the value for |
| 135 | // initial window size on a connection. The lower bound for window size is 64K |
| 136 | // and any value smaller than that will be ignored. |
| 137 | func WithInitialConnWindowSize(s int32) DialOption { |
| 138 | return newFuncDialOption(func(o *dialOptions) { |
| 139 | o.copts.InitialConnWindowSize = s |
| 140 | }) |
| 141 | } |
| 142 | |
| 143 | // WithMaxMsgSize returns a DialOption which sets the maximum message size the |
| 144 | // client can receive. |
| 145 | // |
| 146 | // Deprecated: use WithDefaultCallOptions(MaxCallRecvMsgSize(s)) instead. |
| 147 | func WithMaxMsgSize(s int) DialOption { |
| 148 | return WithDefaultCallOptions(MaxCallRecvMsgSize(s)) |
| 149 | } |
| 150 | |
| 151 | // WithDefaultCallOptions returns a DialOption which sets the default |
| 152 | // CallOptions for calls over the connection. |
| 153 | func WithDefaultCallOptions(cos ...CallOption) DialOption { |
| 154 | return newFuncDialOption(func(o *dialOptions) { |
| 155 | o.callOptions = append(o.callOptions, cos...) |
| 156 | }) |
| 157 | } |
| 158 | |
| 159 | // WithCodec returns a DialOption which sets a codec for message marshaling and |
| 160 | // unmarshaling. |
| 161 | // |
| 162 | // Deprecated: use WithDefaultCallOptions(CallCustomCodec(c)) instead. |
| 163 | func WithCodec(c Codec) DialOption { |
| 164 | return WithDefaultCallOptions(CallCustomCodec(c)) |
| 165 | } |
| 166 | |
| 167 | // WithCompressor returns a DialOption which sets a Compressor to use for |
| 168 | // message compression. It has lower priority than the compressor set by the |
| 169 | // UseCompressor CallOption. |
| 170 | // |
| 171 | // Deprecated: use UseCompressor instead. |
| 172 | func WithCompressor(cp Compressor) DialOption { |
| 173 | return newFuncDialOption(func(o *dialOptions) { |
| 174 | o.cp = cp |
| 175 | }) |
| 176 | } |
| 177 | |
| 178 | // WithDecompressor returns a DialOption which sets a Decompressor to use for |
| 179 | // incoming message decompression. If incoming response messages are encoded |
| 180 | // using the decompressor's Type(), it will be used. Otherwise, the message |
| 181 | // encoding will be used to look up the compressor registered via |
| 182 | // encoding.RegisterCompressor, which will then be used to decompress the |
| 183 | // message. If no compressor is registered for the encoding, an Unimplemented |
| 184 | // status error will be returned. |
| 185 | // |
| 186 | // Deprecated: use encoding.RegisterCompressor instead. |
| 187 | func WithDecompressor(dc Decompressor) DialOption { |
| 188 | return newFuncDialOption(func(o *dialOptions) { |
| 189 | o.dc = dc |
| 190 | }) |
| 191 | } |
| 192 | |
| 193 | // WithBalancer returns a DialOption which sets a load balancer with the v1 API. |
| 194 | // Name resolver will be ignored if this DialOption is specified. |
| 195 | // |
| 196 | // Deprecated: use the new balancer APIs in balancer package and |
| 197 | // WithBalancerName. |
| 198 | func WithBalancer(b Balancer) DialOption { |
| 199 | return newFuncDialOption(func(o *dialOptions) { |
| 200 | o.balancerBuilder = &balancerWrapperBuilder{ |
| 201 | b: b, |
| 202 | } |
| 203 | }) |
| 204 | } |
| 205 | |
| 206 | // WithBalancerName sets the balancer that the ClientConn will be initialized |
| 207 | // with. Balancer registered with balancerName will be used. This function |
| 208 | // panics if no balancer was registered by balancerName. |
| 209 | // |
| 210 | // The balancer cannot be overridden by balancer option specified by service |
| 211 | // config. |
| 212 | // |
| 213 | // This is an EXPERIMENTAL API. |
| 214 | func WithBalancerName(balancerName string) DialOption { |
| 215 | builder := balancer.Get(balancerName) |
| 216 | if builder == nil { |
| 217 | panic(fmt.Sprintf("grpc.WithBalancerName: no balancer is registered for name %v", balancerName)) |
| 218 | } |
| 219 | return newFuncDialOption(func(o *dialOptions) { |
| 220 | o.balancerBuilder = builder |
| 221 | }) |
| 222 | } |
| 223 | |
| 224 | // withResolverBuilder is only for grpclb. |
| 225 | func withResolverBuilder(b resolver.Builder) DialOption { |
| 226 | return newFuncDialOption(func(o *dialOptions) { |
| 227 | o.resolverBuilder = b |
| 228 | }) |
| 229 | } |
| 230 | |
| 231 | // WithServiceConfig returns a DialOption which has a channel to read the |
| 232 | // service configuration. |
| 233 | // |
| 234 | // Deprecated: service config should be received through name resolver, as |
| 235 | // specified here. |
| 236 | // https://github.com/grpc/grpc/blob/master/doc/service_config.md |
| 237 | func WithServiceConfig(c <-chan ServiceConfig) DialOption { |
| 238 | return newFuncDialOption(func(o *dialOptions) { |
| 239 | o.scChan = c |
| 240 | }) |
| 241 | } |
| 242 | |
| 243 | // WithBackoffMaxDelay configures the dialer to use the provided maximum delay |
| 244 | // when backing off after failed connection attempts. |
| 245 | func WithBackoffMaxDelay(md time.Duration) DialOption { |
| 246 | return WithBackoffConfig(BackoffConfig{MaxDelay: md}) |
| 247 | } |
| 248 | |
| 249 | // WithBackoffConfig configures the dialer to use the provided backoff |
| 250 | // parameters after connection failures. |
| 251 | // |
| 252 | // Use WithBackoffMaxDelay until more parameters on BackoffConfig are opened up |
| 253 | // for use. |
| 254 | func WithBackoffConfig(b BackoffConfig) DialOption { |
| 255 | return withBackoff(backoff.Exponential{ |
| 256 | MaxDelay: b.MaxDelay, |
| 257 | }) |
| 258 | } |
| 259 | |
| 260 | // withBackoff sets the backoff strategy used for connectRetryNum after a failed |
| 261 | // connection attempt. |
| 262 | // |
| 263 | // This can be exported if arbitrary backoff strategies are allowed by gRPC. |
| 264 | func withBackoff(bs backoff.Strategy) DialOption { |
| 265 | return newFuncDialOption(func(o *dialOptions) { |
| 266 | o.bs = bs |
| 267 | }) |
| 268 | } |
| 269 | |
| 270 | // WithBlock returns a DialOption which makes caller of Dial blocks until the |
| 271 | // underlying connection is up. Without this, Dial returns immediately and |
| 272 | // connecting the server happens in background. |
| 273 | func WithBlock() DialOption { |
| 274 | return newFuncDialOption(func(o *dialOptions) { |
| 275 | o.block = true |
| 276 | }) |
| 277 | } |
| 278 | |
| 279 | // WithInsecure returns a DialOption which disables transport security for this |
| 280 | // ClientConn. Note that transport security is required unless WithInsecure is |
| 281 | // set. |
| 282 | func WithInsecure() DialOption { |
| 283 | return newFuncDialOption(func(o *dialOptions) { |
| 284 | o.insecure = true |
| 285 | }) |
| 286 | } |
| 287 | |
| 288 | // WithTransportCredentials returns a DialOption which configures a connection |
| 289 | // level security credentials (e.g., TLS/SSL). This should not be used together |
| 290 | // with WithCredentialsBundle. |
| 291 | func WithTransportCredentials(creds credentials.TransportCredentials) DialOption { |
| 292 | return newFuncDialOption(func(o *dialOptions) { |
| 293 | o.copts.TransportCredentials = creds |
| 294 | }) |
| 295 | } |
| 296 | |
| 297 | // WithPerRPCCredentials returns a DialOption which sets credentials and places |
| 298 | // auth state on each outbound RPC. |
| 299 | func WithPerRPCCredentials(creds credentials.PerRPCCredentials) DialOption { |
| 300 | return newFuncDialOption(func(o *dialOptions) { |
| 301 | o.copts.PerRPCCredentials = append(o.copts.PerRPCCredentials, creds) |
| 302 | }) |
| 303 | } |
| 304 | |
| 305 | // WithCredentialsBundle returns a DialOption to set a credentials bundle for |
| 306 | // the ClientConn.WithCreds. This should not be used together with |
| 307 | // WithTransportCredentials. |
| 308 | // |
| 309 | // This API is experimental. |
| 310 | func WithCredentialsBundle(b credentials.Bundle) DialOption { |
| 311 | return newFuncDialOption(func(o *dialOptions) { |
| 312 | o.copts.CredsBundle = b |
| 313 | }) |
| 314 | } |
| 315 | |
| 316 | // WithTimeout returns a DialOption that configures a timeout for dialing a |
| 317 | // ClientConn initially. This is valid if and only if WithBlock() is present. |
| 318 | // |
| 319 | // Deprecated: use DialContext and context.WithTimeout instead. |
| 320 | func WithTimeout(d time.Duration) DialOption { |
| 321 | return newFuncDialOption(func(o *dialOptions) { |
| 322 | o.timeout = d |
| 323 | }) |
| 324 | } |
| 325 | |
| 326 | func withContextDialer(f func(context.Context, string) (net.Conn, error)) DialOption { |
| 327 | return newFuncDialOption(func(o *dialOptions) { |
| 328 | o.copts.Dialer = f |
| 329 | }) |
| 330 | } |
| 331 | |
| 332 | func init() { |
| 333 | internal.WithContextDialer = withContextDialer |
| 334 | internal.WithResolverBuilder = withResolverBuilder |
| 335 | } |
| 336 | |
| 337 | // WithDialer returns a DialOption that specifies a function to use for dialing |
| 338 | // network addresses. If FailOnNonTempDialError() is set to true, and an error |
| 339 | // is returned by f, gRPC checks the error's Temporary() method to decide if it |
| 340 | // should try to reconnect to the network address. |
| 341 | func WithDialer(f func(string, time.Duration) (net.Conn, error)) DialOption { |
| 342 | return withContextDialer( |
| 343 | func(ctx context.Context, addr string) (net.Conn, error) { |
| 344 | if deadline, ok := ctx.Deadline(); ok { |
| 345 | return f(addr, deadline.Sub(time.Now())) |
| 346 | } |
| 347 | return f(addr, 0) |
| 348 | }) |
| 349 | } |
| 350 | |
| 351 | // WithStatsHandler returns a DialOption that specifies the stats handler for |
| 352 | // all the RPCs and underlying network connections in this ClientConn. |
| 353 | func WithStatsHandler(h stats.Handler) DialOption { |
| 354 | return newFuncDialOption(func(o *dialOptions) { |
| 355 | o.copts.StatsHandler = h |
| 356 | }) |
| 357 | } |
| 358 | |
| 359 | // FailOnNonTempDialError returns a DialOption that specifies if gRPC fails on |
| 360 | // non-temporary dial errors. If f is true, and dialer returns a non-temporary |
| 361 | // error, gRPC will fail the connection to the network address and won't try to |
| 362 | // reconnect. The default value of FailOnNonTempDialError is false. |
| 363 | // |
| 364 | // FailOnNonTempDialError only affects the initial dial, and does not do |
| 365 | // anything useful unless you are also using WithBlock(). |
| 366 | // |
| 367 | // This is an EXPERIMENTAL API. |
| 368 | func FailOnNonTempDialError(f bool) DialOption { |
| 369 | return newFuncDialOption(func(o *dialOptions) { |
| 370 | o.copts.FailOnNonTempDialError = f |
| 371 | }) |
| 372 | } |
| 373 | |
| 374 | // WithUserAgent returns a DialOption that specifies a user agent string for all |
| 375 | // the RPCs. |
| 376 | func WithUserAgent(s string) DialOption { |
| 377 | return newFuncDialOption(func(o *dialOptions) { |
| 378 | o.copts.UserAgent = s |
| 379 | }) |
| 380 | } |
| 381 | |
| 382 | // WithKeepaliveParams returns a DialOption that specifies keepalive parameters |
| 383 | // for the client transport. |
| 384 | func WithKeepaliveParams(kp keepalive.ClientParameters) DialOption { |
| 385 | return newFuncDialOption(func(o *dialOptions) { |
| 386 | o.copts.KeepaliveParams = kp |
| 387 | }) |
| 388 | } |
| 389 | |
| 390 | // WithUnaryInterceptor returns a DialOption that specifies the interceptor for |
| 391 | // unary RPCs. |
| 392 | func WithUnaryInterceptor(f UnaryClientInterceptor) DialOption { |
| 393 | return newFuncDialOption(func(o *dialOptions) { |
| 394 | o.unaryInt = f |
| 395 | }) |
| 396 | } |
| 397 | |
| 398 | // WithStreamInterceptor returns a DialOption that specifies the interceptor for |
| 399 | // streaming RPCs. |
| 400 | func WithStreamInterceptor(f StreamClientInterceptor) DialOption { |
| 401 | return newFuncDialOption(func(o *dialOptions) { |
| 402 | o.streamInt = f |
| 403 | }) |
| 404 | } |
| 405 | |
| 406 | // WithAuthority returns a DialOption that specifies the value to be used as the |
| 407 | // :authority pseudo-header. This value only works with WithInsecure and has no |
| 408 | // effect if TransportCredentials are present. |
| 409 | func WithAuthority(a string) DialOption { |
| 410 | return newFuncDialOption(func(o *dialOptions) { |
| 411 | o.authority = a |
| 412 | }) |
| 413 | } |
| 414 | |
| 415 | // WithChannelzParentID returns a DialOption that specifies the channelz ID of |
| 416 | // current ClientConn's parent. This function is used in nested channel creation |
| 417 | // (e.g. grpclb dial). |
| 418 | func WithChannelzParentID(id int64) DialOption { |
| 419 | return newFuncDialOption(func(o *dialOptions) { |
| 420 | o.channelzParentID = id |
| 421 | }) |
| 422 | } |
| 423 | |
| 424 | // WithDisableServiceConfig returns a DialOption that causes grpc to ignore any |
| 425 | // service config provided by the resolver and provides a hint to the resolver |
| 426 | // to not fetch service configs. |
| 427 | func WithDisableServiceConfig() DialOption { |
| 428 | return newFuncDialOption(func(o *dialOptions) { |
| 429 | o.disableServiceConfig = true |
| 430 | }) |
| 431 | } |
| 432 | |
| 433 | // WithDisableRetry returns a DialOption that disables retries, even if the |
| 434 | // service config enables them. This does not impact transparent retries, which |
| 435 | // will happen automatically if no data is written to the wire or if the RPC is |
| 436 | // unprocessed by the remote server. |
| 437 | // |
| 438 | // Retry support is currently disabled by default, but will be enabled by |
| 439 | // default in the future. Until then, it may be enabled by setting the |
| 440 | // environment variable "GRPC_GO_RETRY" to "on". |
| 441 | // |
| 442 | // This API is EXPERIMENTAL. |
| 443 | func WithDisableRetry() DialOption { |
| 444 | return newFuncDialOption(func(o *dialOptions) { |
| 445 | o.disableRetry = true |
| 446 | }) |
| 447 | } |
| 448 | |
| 449 | // WithMaxHeaderListSize returns a DialOption that specifies the maximum |
| 450 | // (uncompressed) size of header list that the client is prepared to accept. |
| 451 | func WithMaxHeaderListSize(s uint32) DialOption { |
| 452 | return newFuncDialOption(func(o *dialOptions) { |
| 453 | o.copts.MaxHeaderListSize = &s |
| 454 | }) |
| 455 | } |
| 456 | |
| 457 | func defaultDialOptions() dialOptions { |
| 458 | return dialOptions{ |
| 459 | disableRetry: !envconfig.Retry, |
| 460 | copts: transport.ConnectOptions{ |
| 461 | WriteBufferSize: defaultWriteBufSize, |
| 462 | ReadBufferSize: defaultReadBufSize, |
| 463 | }, |
| 464 | } |
| 465 | } |