21extern const std::string kType;
22extern const std::string kSpanKind;
23extern const std::string kSpanKindServer;
24extern const std::string kSpanKindClient;
25extern const std::string kSpanKindInternal;
26extern const std::string kHttpUrl;
27extern const std::string kUrlFull;
28extern const std::string kHttpUrlTemplate;
29extern const std::string kHttpMetaType;
30extern const std::string kHttpMethod;
31extern const std::string kHttpRequestMethod;
32extern const std::string kHttpRoute;
33extern const std::string kHttpStatusCode;
34extern const std::string kHttpResponseStatusCode;
35extern const std::string kAttempts;
36extern const std::string kMaxAttempts;
37extern const std::string kTimeoutMs;
38extern const std::string kErrorFlag;
39extern const std::string kErrorMessage;
41extern const std::string kRpcSystem;
42extern const std::string kRpcService;
43extern const std::string kRpcMethod;
44extern const std::string kGrpcCode;
46extern const std::string kDatabaseType;
47extern const std::string kDatabaseMongoType;
48extern const std::string kDatabasePostgresType;
49extern const std::string kDatabaseRedisType;
51extern const std::string kDatabaseCollection;
52extern const std::string kDatabaseInstance;
53extern const std::string kDatabaseStatement;
54extern const std::string kDatabaseStatementName;
55extern const std::string kDatabaseStatementDescription;
57extern const std::string kPeerAddress;
58extern const std::string kServerAddress;
60extern const std::string kUserAgent;