forked from grpc/grpc-java
-
Notifications
You must be signed in to change notification settings - Fork 0
/
LoadBalancerConfigFactory.java
350 lines (314 loc) · 14.9 KB
/
LoadBalancerConfigFactory.java
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
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
/*
* Copyright 2022 The gRPC Authors
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package io.grpc.xds;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.Iterables;
import com.google.protobuf.Any;
import com.google.protobuf.InvalidProtocolBufferException;
import com.google.protobuf.Struct;
import com.google.protobuf.util.JsonFormat;
import io.envoyproxy.envoy.config.cluster.v3.Cluster;
import io.envoyproxy.envoy.config.cluster.v3.Cluster.LeastRequestLbConfig;
import io.envoyproxy.envoy.config.cluster.v3.Cluster.RingHashLbConfig;
import io.envoyproxy.envoy.config.cluster.v3.LoadBalancingPolicy;
import io.envoyproxy.envoy.config.cluster.v3.LoadBalancingPolicy.Policy;
import io.envoyproxy.envoy.extensions.load_balancing_policies.ring_hash.v3.RingHash;
import io.envoyproxy.envoy.extensions.load_balancing_policies.round_robin.v3.RoundRobin;
import io.envoyproxy.envoy.extensions.load_balancing_policies.wrr_locality.v3.WrrLocality;
import io.grpc.InternalLogId;
import io.grpc.LoadBalancerRegistry;
import io.grpc.internal.JsonParser;
import io.grpc.xds.ClientXdsClient.ResourceInvalidException;
import io.grpc.xds.LoadBalancerConfigFactory.LoadBalancingPolicyConverter.MaxRecursionReachedException;
import io.grpc.xds.XdsLogger.XdsLogLevel;
import java.io.IOException;
import java.util.Map;
/**
* Creates service config JSON load balancer config objects for a given xDS Cluster message.
* Supports both the "legacy" configuration style and the new, more advanced one that utilizes the
* xDS "typed extension" mechanism.
*
* <p>Legacy configuration is done by setting the lb_policy enum field and any supporting
* configuration fields needed by the particular policy.
*
* <p>The new approach is to set the load_balancing_policy field that contains both the policy
* selection as well as any supporting configuration data. Providing a list of acceptable policies
* is also supported. Note that if this field is used, it will override any configuration set using
* the legacy approach. The new configuration approach is explained in detail in the <a href="
* https://github.com/grpc/proposal/blob/master/A52-xds-custom-lb-policies.md">Custom LB Policies
* gRFC</a>
*/
class LoadBalancerConfigFactory {
private static final XdsLogger logger = XdsLogger.withLogId(
InternalLogId.allocate("xds-client-lbconfig-factory", null));
static final String ROUND_ROBIN_FIELD_NAME = "round_robin";
static final String RING_HASH_FIELD_NAME = "ring_hash_experimental";
static final String MIN_RING_SIZE_FIELD_NAME = "minRingSize";
static final String MAX_RING_SIZE_FIELD_NAME = "maxRingSize";
static final String LEAST_REQUEST_FIELD_NAME = "least_request_experimental";
static final String CHOICE_COUNT_FIELD_NAME = "choiceCount";
static final String WRR_LOCALITY_FIELD_NAME = "wrr_locality_experimental";
static final String CHILD_POLICY_FIELD = "childPolicy";
/**
* Factory method for creating a new {link LoadBalancerConfigConverter} for a given xDS {@link
* Cluster}.
*
* @throws ResourceInvalidException If the {@link Cluster} has an invalid LB configuration.
*/
static ImmutableMap<String, ?> newConfig(Cluster cluster, boolean enableLeastRequest,
boolean enableCustomLbConfig)
throws ResourceInvalidException {
// The new load_balancing_policy will always be used if it is set, but for backward
// compatibility we will fall back to using the old lb_policy field if the new field is not set.
if (cluster.hasLoadBalancingPolicy() && enableCustomLbConfig) {
try {
return LoadBalancingPolicyConverter.convertToServiceConfig(cluster.getLoadBalancingPolicy(),
0);
} catch (MaxRecursionReachedException e) {
throw new ResourceInvalidException("Maximum LB config recursion depth reached", e);
}
} else {
return LegacyLoadBalancingPolicyConverter.convertToServiceConfig(cluster, enableLeastRequest);
}
}
/**
* Builds a service config JSON object for the ring_hash load balancer config based on the given
* config values.
*/
private static ImmutableMap<String, ?> buildRingHashConfig(Long minRingSize, Long maxRingSize) {
ImmutableMap.Builder<String, Object> configBuilder = ImmutableMap.builder();
if (minRingSize != null) {
configBuilder.put(MIN_RING_SIZE_FIELD_NAME, minRingSize.doubleValue());
}
if (maxRingSize != null) {
configBuilder.put(MAX_RING_SIZE_FIELD_NAME, maxRingSize.doubleValue());
}
return ImmutableMap.of(RING_HASH_FIELD_NAME, configBuilder.buildOrThrow());
}
/**
* Builds a service config JSON object for the least_request load balancer config based on the
* given config values..
*/
private static ImmutableMap<String, ?> buildLeastRequestConfig(Integer choiceCount) {
ImmutableMap.Builder<String, Object> configBuilder = ImmutableMap.builder();
if (choiceCount != null) {
configBuilder.put(CHOICE_COUNT_FIELD_NAME, choiceCount.doubleValue());
}
return ImmutableMap.of(LEAST_REQUEST_FIELD_NAME, configBuilder.buildOrThrow());
}
/**
* Builds a service config JSON wrr_locality by wrapping another policy config.
*/
private static ImmutableMap<String, ?> buildWrrLocalityConfig(
ImmutableMap<String, ?> childConfig) {
return ImmutableMap.<String, Object>builder().put(WRR_LOCALITY_FIELD_NAME,
ImmutableMap.of(CHILD_POLICY_FIELD, ImmutableList.of(childConfig))).buildOrThrow();
}
/**
* Builds an empty service config JSON config object for round robin (it is not configurable).
*/
private static ImmutableMap<String, ?> buildRoundRobinConfig() {
return ImmutableMap.of(ROUND_ROBIN_FIELD_NAME, ImmutableMap.of());
}
/**
* Responsible for converting from a {@code envoy.config.cluster.v3.LoadBalancingPolicy} proto
* message to a gRPC service config format.
*/
static class LoadBalancingPolicyConverter {
private static final int MAX_RECURSION = 16;
/**
* Converts a {@link LoadBalancingPolicy} object to a service config JSON object.
*/
private static ImmutableMap<String, ?> convertToServiceConfig(
LoadBalancingPolicy loadBalancingPolicy, int recursionDepth)
throws ResourceInvalidException, MaxRecursionReachedException {
if (recursionDepth > MAX_RECURSION) {
throw new MaxRecursionReachedException();
}
ImmutableMap<String, ?> serviceConfig = null;
for (Policy policy : loadBalancingPolicy.getPoliciesList()) {
Any typedConfig = policy.getTypedExtensionConfig().getTypedConfig();
try {
if (typedConfig.is(RingHash.class)) {
serviceConfig = convertRingHashConfig(typedConfig.unpack(RingHash.class));
} else if (typedConfig.is(WrrLocality.class)) {
serviceConfig = convertWrrLocalityConfig(typedConfig.unpack(WrrLocality.class),
recursionDepth);
} else if (typedConfig.is(RoundRobin.class)) {
serviceConfig = convertRoundRobinConfig();
} else if (typedConfig.is(com.github.xds.type.v3.TypedStruct.class)) {
serviceConfig = convertCustomConfig(
typedConfig.unpack(com.github.xds.type.v3.TypedStruct.class));
} else if (typedConfig.is(com.github.udpa.udpa.type.v1.TypedStruct.class)) {
serviceConfig = convertCustomConfig(
typedConfig.unpack(com.github.udpa.udpa.type.v1.TypedStruct.class));
}
// TODO: support least_request once it is added to the envoy protos.
} catch (InvalidProtocolBufferException e) {
throw new ResourceInvalidException(
"Unable to unpack typedConfig for: " + typedConfig.getTypeUrl(), e);
}
// The service config is expected to have a single root entry, where the name of that entry
// is the name of the policy. A Load balancer with this name must exist in the registry.
if (serviceConfig == null || LoadBalancerRegistry.getDefaultRegistry()
.getProvider(Iterables.getOnlyElement(serviceConfig.keySet())) == null) {
logger.log(XdsLogLevel.WARNING, "Policy {0} not found in the LB registry, skipping",
typedConfig.getTypeUrl());
continue;
} else {
return serviceConfig;
}
}
// If we could not find a Policy that we could both convert as well as find a provider for
// then we have an invalid LB policy configuration.
throw new ResourceInvalidException("Invalid LoadBalancingPolicy: " + loadBalancingPolicy);
}
/**
* Converts a ring_hash {@link Any} configuration to service config format.
*/
private static ImmutableMap<String, ?> convertRingHashConfig(RingHash ringHash)
throws ResourceInvalidException {
// The hash function needs to be validated here as it is not exposed in the returned
// configuration for later validation.
if (RingHash.HashFunction.XX_HASH != ringHash.getHashFunction()) {
throw new ResourceInvalidException(
"Invalid ring hash function: " + ringHash.getHashFunction());
}
return buildRingHashConfig(
ringHash.hasMinimumRingSize() ? ringHash.getMinimumRingSize().getValue() : null,
ringHash.hasMaximumRingSize() ? ringHash.getMaximumRingSize().getValue() : null);
}
/**
* Converts a wrr_locality {@link Any} configuration to service config format.
*/
private static ImmutableMap<String, ?> convertWrrLocalityConfig(WrrLocality wrrLocality,
int recursionDepth) throws ResourceInvalidException,
MaxRecursionReachedException {
return buildWrrLocalityConfig(
convertToServiceConfig(wrrLocality.getEndpointPickingPolicy(), recursionDepth + 1));
}
/**
* "Converts" a round_robin configuration to service config format.
*/
private static ImmutableMap<String, ?> convertRoundRobinConfig() {
return buildRoundRobinConfig();
}
/**
* Converts a custom TypedStruct LB config to service config format.
*/
@SuppressWarnings("unchecked")
private static ImmutableMap<String, ?> convertCustomConfig(
com.github.xds.type.v3.TypedStruct configTypedStruct)
throws ResourceInvalidException {
return ImmutableMap.of(parseCustomConfigTypeName(configTypedStruct.getTypeUrl()),
(Map<String, ?>) parseCustomConfigJson(configTypedStruct.getValue()));
}
/**
* Converts a custom UDPA (legacy) TypedStruct LB config to service config format.
*/
@SuppressWarnings("unchecked")
private static ImmutableMap<String, ?> convertCustomConfig(
com.github.udpa.udpa.type.v1.TypedStruct configTypedStruct)
throws ResourceInvalidException {
return ImmutableMap.of(parseCustomConfigTypeName(configTypedStruct.getTypeUrl()),
(Map<String, ?>) parseCustomConfigJson(configTypedStruct.getValue()));
}
/**
* Print the config Struct into JSON and then parse that into our internal representation.
*/
private static Object parseCustomConfigJson(Struct configStruct)
throws ResourceInvalidException {
Object rawJsonConfig = null;
try {
rawJsonConfig = JsonParser.parse(JsonFormat.printer().print(configStruct));
} catch (IOException e) {
throw new ResourceInvalidException("Unable to parse custom LB config JSON", e);
}
if (!(rawJsonConfig instanceof Map)) {
throw new ResourceInvalidException("Custom LB config does not contain a JSON object");
}
return rawJsonConfig;
}
private static String parseCustomConfigTypeName(String customConfigTypeName) {
if (customConfigTypeName.contains("/")) {
customConfigTypeName = customConfigTypeName.substring(
customConfigTypeName.lastIndexOf("/") + 1);
}
return customConfigTypeName;
}
// Used to signal that the LB config goes too deep.
static class MaxRecursionReachedException extends Exception {
static final long serialVersionUID = 1L;
}
}
/**
* Builds a JSON LB configuration based on the old style of using the xDS Cluster proto message.
* The lb_policy field is used to select the policy and configuration is extracted from various
* policy specific fields in Cluster.
*/
static class LegacyLoadBalancingPolicyConverter {
/**
* Factory method for creating a new {link LoadBalancerConfigConverter} for a given xDS {@link
* Cluster}.
*
* @throws ResourceInvalidException If the {@link Cluster} has an invalid LB configuration.
*/
static ImmutableMap<String, ?> convertToServiceConfig(Cluster cluster,
boolean enableLeastRequest) throws ResourceInvalidException {
switch (cluster.getLbPolicy()) {
case RING_HASH:
return convertRingHashConfig(cluster);
case ROUND_ROBIN:
return buildWrrLocalityConfig(buildRoundRobinConfig());
case LEAST_REQUEST:
if (enableLeastRequest) {
return buildWrrLocalityConfig(convertLeastRequestConfig(cluster));
}
break;
default:
}
throw new ResourceInvalidException(
"Cluster " + cluster.getName() + ": unsupported lb policy: " + cluster.getLbPolicy());
}
/**
* Creates a new ring_hash service config JSON object based on the old {@link RingHashLbConfig}
* config message.
*/
private static ImmutableMap<String, ?> convertRingHashConfig(Cluster cluster)
throws ResourceInvalidException {
RingHashLbConfig lbConfig = cluster.getRingHashLbConfig();
// The hash function needs to be validated here as it is not exposed in the returned
// configuration for later validation.
if (lbConfig.getHashFunction() != RingHashLbConfig.HashFunction.XX_HASH) {
throw new ResourceInvalidException(
"Cluster " + cluster.getName() + ": invalid ring hash function: " + lbConfig);
}
return buildRingHashConfig(
lbConfig.hasMinimumRingSize() ? (Long) lbConfig.getMinimumRingSize().getValue() : null,
lbConfig.hasMaximumRingSize() ? (Long) lbConfig.getMaximumRingSize().getValue() : null);
}
/**
* Creates a new least_request service config JSON object based on the old {@link
* LeastRequestLbConfig} config message.
*/
private static ImmutableMap<String, ?> convertLeastRequestConfig(Cluster cluster) {
LeastRequestLbConfig lbConfig = cluster.getLeastRequestLbConfig();
return buildLeastRequestConfig(
lbConfig.hasChoiceCount() ? (Integer) lbConfig.getChoiceCount().getValue() : null);
}
}
}