forked from OpenFeign/feign
-
Notifications
You must be signed in to change notification settings - Fork 0
Expand file tree
/
Copy pathFeign.java
More file actions
313 lines (278 loc) · 11 KB
/
Feign.java
File metadata and controls
313 lines (278 loc) · 11 KB
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
/**
* Copyright 2012-2021 The Feign 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 feign;
import feign.Logger.NoOpLogger;
import feign.ReflectiveFeign.ParseHandlersByName;
import feign.Request.Options;
import feign.Target.HardCodedTarget;
import feign.codec.Decoder;
import feign.codec.Encoder;
import feign.codec.ErrorDecoder;
import feign.querymap.FieldQueryMapEncoder;
import java.io.IOException;
import java.lang.reflect.Method;
import java.lang.reflect.Type;
import java.util.ArrayList;
import java.util.List;
import java.util.stream.Collectors;
import static feign.ExceptionPropagationPolicy.NONE;
/**
* Feign's purpose is to ease development against http apis that feign restfulness. <br>
* In implementation, Feign is a {@link Feign#newInstance factory} for generating {@link Target
* targeted} http apis.
*/
public abstract class Feign {
public static Builder builder() {
return new Builder();
}
/**
* Configuration keys are formatted as unresolved <a href=
* "http://docs.oracle.com/javase/6/docs/jdk/api/javadoc/doclet/com/sun/javadoc/SeeTag.html" >see
* tags</a>. This method exposes that format, in case you need to create the same value as
* {@link MethodMetadata#configKey()} for correlation purposes.
*
* <p>
* Here are some sample encodings:
*
* <pre>
* <ul>
* <li>{@code Route53}: would match a class {@code route53.Route53}</li>
* <li>{@code Route53#list()}: would match a method {@code route53.Route53#list()}</li>
* <li>{@code Route53#listAt(Marker)}: would match a method {@code
* route53.Route53#listAt(Marker)}</li>
* <li>{@code Route53#listByNameAndType(String, String)}: would match a method {@code
* route53.Route53#listAt(String, String)}</li>
* </ul>
* </pre>
*
* Note that there is no whitespace expected in a key!
*
* @param targetType {@link feign.Target#type() type} of the Feign interface.
* @param method invoked method, present on {@code type} or its super.
* @see MethodMetadata#configKey()
*/
//route53.Route53#listAt(String, String)
public static String configKey(Class targetType, Method method) {
StringBuilder builder = new StringBuilder();
builder.append(targetType.getSimpleName());
builder.append('#').append(method.getName()).append('(');
for (Type param : method.getGenericParameterTypes()) {
param = Types.resolve(targetType, targetType, param);
builder.append(Types.getRawType(param).getSimpleName()).append(',');
}
if (method.getParameterTypes().length > 0) {
builder.deleteCharAt(builder.length() - 1);
}
return builder.append(')').toString();
}
/**
* @deprecated use {@link #configKey(Class, Method)} instead.
*/
@Deprecated
public static String configKey(Method method) {
return configKey(method.getDeclaringClass(), method);
}
/**
* Returns a new instance of an HTTP API, defined by annotations in the {@link Feign Contract},
* for the specified {@code target}. You should cache this result.
*/
public abstract <T> T newInstance(Target<T> target);
public static class Builder {
private final List<RequestInterceptor> requestInterceptors =
new ArrayList<RequestInterceptor>();
private Logger.Level logLevel = Logger.Level.NONE;
private Contract contract = new Contract.Default();
private Client client = new Client.Default(null, null);
private Retryer retryer = new Retryer.Default();
private Logger logger = new NoOpLogger();
private Encoder encoder = new Encoder.Default();
private Decoder decoder = new Decoder.Default();
private QueryMapEncoder queryMapEncoder = new FieldQueryMapEncoder();
private ErrorDecoder errorDecoder = new ErrorDecoder.Default();
private Options options = new Options();
private InvocationHandlerFactory invocationHandlerFactory =
new InvocationHandlerFactory.Default();
private boolean decode404;
private boolean closeAfterDecode = true;
private ExceptionPropagationPolicy propagationPolicy = NONE;
private boolean forceDecoding = false;
private List<Capability> capabilities = new ArrayList<>();
public Builder logLevel(Logger.Level logLevel) {
this.logLevel = logLevel;
return this;
}
public Builder contract(Contract contract) {
this.contract = contract;
return this;
}
public Builder client(Client client) {
this.client = client;
return this;
}
public Builder retryer(Retryer retryer) {
this.retryer = retryer;
return this;
}
public Builder logger(Logger logger) {
this.logger = logger;
return this;
}
public Builder encoder(Encoder encoder) {
this.encoder = encoder;
return this;
}
public Builder decoder(Decoder decoder) {
this.decoder = decoder;
return this;
}
public Builder queryMapEncoder(QueryMapEncoder queryMapEncoder) {
this.queryMapEncoder = queryMapEncoder;
return this;
}
/**
* Allows to map the response before passing it to the decoder.
*/
public Builder mapAndDecode(ResponseMapper mapper, Decoder decoder) {
this.decoder = new ResponseMappingDecoder(mapper, decoder);
return this;
}
/**
* This flag indicates that the {@link #decoder(Decoder) decoder} should process responses with
* 404 status, specifically returning null or empty instead of throwing {@link FeignException}.
*
* <p/>
* All first-party (ex gson) decoders return well-known empty values defined by
* {@link Util#emptyValueOf}. To customize further, wrap an existing {@link #decoder(Decoder)
* decoder} or make your own.
*
* <p/>
* This flag only works with 404, as opposed to all or arbitrary status codes. This was an
* explicit decision: 404 -> empty is safe, common and doesn't complicate redirection, retry or
* fallback policy. If your server returns a different status for not-found, correct via a
* custom {@link #client(Client) client}.
*
* @since 8.12
*/
public Builder decode404() {
this.decode404 = true;
return this;
}
public Builder errorDecoder(ErrorDecoder errorDecoder) {
this.errorDecoder = errorDecoder;
return this;
}
public Builder options(Options options) {
this.options = options;
return this;
}
/**
* Adds a single request interceptor to the builder.
*/
public Builder requestInterceptor(RequestInterceptor requestInterceptor) {
this.requestInterceptors.add(requestInterceptor);
return this;
}
/**
* Sets the full set of request interceptors for the builder, overwriting any previous
* interceptors.
*/
public Builder requestInterceptors(Iterable<RequestInterceptor> requestInterceptors) {
this.requestInterceptors.clear();
for (RequestInterceptor requestInterceptor : requestInterceptors) {
this.requestInterceptors.add(requestInterceptor);
}
return this;
}
/**
* Allows you to override how reflective dispatch works inside of Feign.
*/
public Builder invocationHandlerFactory(InvocationHandlerFactory invocationHandlerFactory) {
this.invocationHandlerFactory = invocationHandlerFactory;
return this;
}
/**
* This flag indicates that the response should not be automatically closed upon completion of
* decoding the message. This should be set if you plan on processing the response into a
* lazy-evaluated construct, such as a {@link java.util.Iterator}.
*
* </p>
* Feign standard decoders do not have built in support for this flag. If you are using this
* flag, you MUST also use a custom Decoder, and be sure to close all resources appropriately
* somewhere in the Decoder (you can use {@link Util#ensureClosed} for convenience).
*
* @since 9.6
*
*/
public Builder doNotCloseAfterDecode() {
this.closeAfterDecode = false;
return this;
}
public Builder exceptionPropagationPolicy(ExceptionPropagationPolicy propagationPolicy) {
this.propagationPolicy = propagationPolicy;
return this;
}
public Builder addCapability(Capability capability) {
this.capabilities.add(capability);
return this;
}
/**
* Internal - used to indicate that the decoder should be immediately called
*/
Builder forceDecoding() {
this.forceDecoding = true;
return this;
}
public <T> T target(Class<T> apiType, String url) {
return target(new HardCodedTarget<T>(apiType, url));
}
public <T> T target(Target<T> target) {
return build().newInstance(target);
}
public Feign build() {
Client client = Capability.enrich(this.client, capabilities);
Retryer retryer = Capability.enrich(this.retryer, capabilities);
List<RequestInterceptor> requestInterceptors = this.requestInterceptors.stream()
.map(ri -> Capability.enrich(ri, capabilities))
.collect(Collectors.toList());
Logger logger = Capability.enrich(this.logger, capabilities);
Contract contract = Capability.enrich(this.contract, capabilities);
Options options = Capability.enrich(this.options, capabilities);
Encoder encoder = Capability.enrich(this.encoder, capabilities);
Decoder decoder = Capability.enrich(this.decoder, capabilities);
InvocationHandlerFactory invocationHandlerFactory =
Capability.enrich(this.invocationHandlerFactory, capabilities);
QueryMapEncoder queryMapEncoder = Capability.enrich(this.queryMapEncoder, capabilities);
SynchronousMethodHandler.Factory synchronousMethodHandlerFactory =
new SynchronousMethodHandler.Factory(client, retryer, requestInterceptors, logger,
logLevel, decode404, closeAfterDecode, propagationPolicy, forceDecoding);
ParseHandlersByName handlersByName =
new ParseHandlersByName(contract, options, encoder, decoder, queryMapEncoder,
errorDecoder, synchronousMethodHandlerFactory);
// 构造反射的feign
return new ReflectiveFeign(handlersByName, invocationHandlerFactory, queryMapEncoder);
}
}
public static class ResponseMappingDecoder implements Decoder {
private final ResponseMapper mapper;
private final Decoder delegate;
public ResponseMappingDecoder(ResponseMapper mapper, Decoder decoder) {
this.mapper = mapper;
this.delegate = decoder;
}
@Override
public Object decode(Response response, Type type) throws IOException {
return delegate.decode(mapper.map(response, type), type);
}
}
}