1 //
2 // Copyright 2015 gRPC authors.
3 //
4 // Licensed under the Apache License, Version 2.0 (the "License");
5 // you may not use this file except in compliance with the License.
6 // You may obtain a copy of the License at
7 //
8 // http://www.apache.org/licenses/LICENSE-2.0
9 //
10 // Unless required by applicable law or agreed to in writing, software
11 // distributed under the License is distributed on an "AS IS" BASIS,
12 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 // See the License for the specific language governing permissions and
14 // limitations under the License.
15 //
16
17 #include <grpc/support/port_platform.h>
18
19 #include "src/core/lib/transport/service_config.h"
20
21 #include <string.h>
22
23 #include <grpc/impl/codegen/grpc_types.h>
24 #include <grpc/support/alloc.h>
25 #include <grpc/support/log.h>
26 #include <grpc/support/string_util.h>
27
28 #include "src/core/lib/gpr/string.h"
29 #include "src/core/lib/json/json.h"
30 #include "src/core/lib/slice/slice_hash_table.h"
31 #include "src/core/lib/slice/slice_internal.h"
32 #include "src/core/lib/slice/slice_string_helpers.h"
33
34 namespace grpc_core {
35
Create(const char * json)36 UniquePtr<ServiceConfig> ServiceConfig::Create(const char* json) {
37 UniquePtr<char> json_string(gpr_strdup(json));
38 grpc_json* json_tree = grpc_json_parse_string(json_string.get());
39 if (json_tree == nullptr) {
40 gpr_log(GPR_INFO, "failed to parse JSON for service config");
41 return nullptr;
42 }
43 return MakeUnique<ServiceConfig>(std::move(json_string), json_tree);
44 }
45
ServiceConfig(UniquePtr<char> json_string,grpc_json * json_tree)46 ServiceConfig::ServiceConfig(UniquePtr<char> json_string, grpc_json* json_tree)
47 : json_string_(std::move(json_string)), json_tree_(json_tree) {}
48
~ServiceConfig()49 ServiceConfig::~ServiceConfig() { grpc_json_destroy(json_tree_); }
50
GetLoadBalancingPolicyName() const51 const char* ServiceConfig::GetLoadBalancingPolicyName() const {
52 if (json_tree_->type != GRPC_JSON_OBJECT || json_tree_->key != nullptr) {
53 return nullptr;
54 }
55 const char* lb_policy_name = nullptr;
56 for (grpc_json* field = json_tree_->child; field != nullptr;
57 field = field->next) {
58 if (field->key == nullptr) return nullptr;
59 if (strcmp(field->key, "loadBalancingPolicy") == 0) {
60 if (lb_policy_name != nullptr) return nullptr; // Duplicate.
61 if (field->type != GRPC_JSON_STRING) return nullptr;
62 lb_policy_name = field->value;
63 }
64 }
65 return lb_policy_name;
66 }
67
CountNamesInMethodConfig(grpc_json * json)68 int ServiceConfig::CountNamesInMethodConfig(grpc_json* json) {
69 int num_names = 0;
70 for (grpc_json* field = json->child; field != nullptr; field = field->next) {
71 if (field->key != nullptr && strcmp(field->key, "name") == 0) {
72 if (field->type != GRPC_JSON_ARRAY) return -1;
73 for (grpc_json* name = field->child; name != nullptr; name = name->next) {
74 if (name->type != GRPC_JSON_OBJECT) return -1;
75 ++num_names;
76 }
77 }
78 }
79 return num_names;
80 }
81
ParseJsonMethodName(grpc_json * json)82 UniquePtr<char> ServiceConfig::ParseJsonMethodName(grpc_json* json) {
83 if (json->type != GRPC_JSON_OBJECT) return nullptr;
84 const char* service_name = nullptr;
85 const char* method_name = nullptr;
86 for (grpc_json* child = json->child; child != nullptr; child = child->next) {
87 if (child->key == nullptr) return nullptr;
88 if (child->type != GRPC_JSON_STRING) return nullptr;
89 if (strcmp(child->key, "service") == 0) {
90 if (service_name != nullptr) return nullptr; // Duplicate.
91 if (child->value == nullptr) return nullptr;
92 service_name = child->value;
93 } else if (strcmp(child->key, "method") == 0) {
94 if (method_name != nullptr) return nullptr; // Duplicate.
95 if (child->value == nullptr) return nullptr;
96 method_name = child->value;
97 }
98 }
99 if (service_name == nullptr) return nullptr; // Required field.
100 char* path;
101 gpr_asprintf(&path, "/%s/%s", service_name,
102 method_name == nullptr ? "*" : method_name);
103 return UniquePtr<char>(path);
104 }
105
106 } // namespace grpc_core
107