This is a constant value that identifies the proximate cause of the error. Error reasons are unique within a particular domain of errors. This should be at most 63 characters and match a regular expression of[A-Z][A-Z0-9_]+[A-Z0-9], which represents UPPER_SNAKE_CASE.
Returns
Type
Description
std::string const &
domain() const
The logical grouping to which the "reason" belongs.
The error domain is typically the registered service name of the tool or product that generates the error. Example: "pubsub.googleapis.com". If the error is generated by some common infrastructure, the error domain must be a globally unique value that identifies the infrastructure. For Google API infrastructure, the error domain is "googleapis.com".
For errors generated by the C++ client libraries the domain isgcloud-cpp.
Returns
Type
Description
std::string const &
metadata() const
Additional structured details about this error.
Keys should match the regular expression[a-zA-Z0-9-_]and be limited to 64 characters in length.
When identifying the current value of an exceeded limit, the units should be contained in the key, not the value. For example, if the client exceeds the number of instances that can be created in a single (batch) request return{"instanceLimitPerRequest": "100"}rather than{"instanceLimit": "100/request"}.
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Hard to understand","hardToUnderstand","thumb-down"],["Incorrect information or sample code","incorrectInformationOrSampleCode","thumb-down"],["Missing the information/samples I need","missingTheInformationSamplesINeed","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-09-04 UTC."],[[["\u003cp\u003eThe \u003ccode\u003eErrorInfo\u003c/code\u003e class provides structured details about the cause of an error, including a reason, domain, and metadata.\u003c/p\u003e\n"],["\u003cp\u003eVersion 2.37.0-rc is the latest version, and there are many previous versions of this class available, ranging down to version 2.10.1.\u003c/p\u003e\n"],["\u003cp\u003eThe \u003ccode\u003ereason()\u003c/code\u003e function returns a constant string representing the error's proximate cause, formatted in UPPER_SNAKE_CASE with a maximum length of 63 characters.\u003c/p\u003e\n"],["\u003cp\u003eThe \u003ccode\u003edomain()\u003c/code\u003e function identifies the logical group of the error, and for C++ client library errors, the domain will be \u003ccode\u003egcloud-cpp\u003c/code\u003e.\u003c/p\u003e\n"],["\u003cp\u003eThe \u003ccode\u003emetadata()\u003c/code\u003e function allows you to view the details of the error that are structured, its keys are limited to 64 characters in length and must match the regular expression \u003ccode\u003e[a-zA-Z0-9-_]\u003c/code\u003e.\u003c/p\u003e\n"]]],[],null,["# Class ErrorInfo (2.35.0)\n\nVersion 2.35.0keyboard_arrow_down\n\n- [2.42.0-rc (latest)](/cpp/docs/reference/common/latest/classgoogle_1_1cloud_1_1ErrorInfo)\n- [2.41.0](/cpp/docs/reference/common/2.41.0/classgoogle_1_1cloud_1_1ErrorInfo)\n- [2.40.0](/cpp/docs/reference/common/2.40.0/classgoogle_1_1cloud_1_1ErrorInfo)\n- [2.39.0](/cpp/docs/reference/common/2.39.0/classgoogle_1_1cloud_1_1ErrorInfo)\n- [2.38.0](/cpp/docs/reference/common/2.38.0/classgoogle_1_1cloud_1_1ErrorInfo)\n- [2.37.0](/cpp/docs/reference/common/2.37.0/classgoogle_1_1cloud_1_1ErrorInfo)\n- [2.36.0](/cpp/docs/reference/common/2.36.0/classgoogle_1_1cloud_1_1ErrorInfo)\n- [2.35.0](/cpp/docs/reference/common/2.35.0/classgoogle_1_1cloud_1_1ErrorInfo)\n- [2.34.0](/cpp/docs/reference/common/2.34.0/classgoogle_1_1cloud_1_1ErrorInfo)\n- [2.33.0](/cpp/docs/reference/common/2.33.0/classgoogle_1_1cloud_1_1ErrorInfo)\n- [2.32.0](/cpp/docs/reference/common/2.32.0/classgoogle_1_1cloud_1_1ErrorInfo)\n- [2.31.0](/cpp/docs/reference/common/2.31.0/classgoogle_1_1cloud_1_1ErrorInfo)\n- [2.30.0](/cpp/docs/reference/common/2.30.0/classgoogle_1_1cloud_1_1ErrorInfo)\n- [2.29.0](/cpp/docs/reference/common/2.29.0/classgoogle_1_1cloud_1_1ErrorInfo)\n- [2.28.0](/cpp/docs/reference/common/2.28.0/classgoogle_1_1cloud_1_1ErrorInfo)\n- [2.27.0](/cpp/docs/reference/common/2.27.0/classgoogle_1_1cloud_1_1ErrorInfo)\n- [2.26.0](/cpp/docs/reference/common/2.26.0/classgoogle_1_1cloud_1_1ErrorInfo)\n- [2.25.1](/cpp/docs/reference/common/2.25.1/classgoogle_1_1cloud_1_1ErrorInfo)\n- [2.24.0](/cpp/docs/reference/common/2.24.0/classgoogle_1_1cloud_1_1ErrorInfo)\n- [2.23.0](/cpp/docs/reference/common/2.23.0/classgoogle_1_1cloud_1_1ErrorInfo)\n- [2.22.1](/cpp/docs/reference/common/2.22.1/classgoogle_1_1cloud_1_1ErrorInfo)\n- [2.21.0](/cpp/docs/reference/common/2.21.0/classgoogle_1_1cloud_1_1ErrorInfo)\n- [2.20.0](/cpp/docs/reference/common/2.20.0/classgoogle_1_1cloud_1_1ErrorInfo)\n- [2.19.0](/cpp/docs/reference/common/2.19.0/classgoogle_1_1cloud_1_1ErrorInfo)\n- [2.18.0](/cpp/docs/reference/common/2.18.0/classgoogle_1_1cloud_1_1ErrorInfo)\n- [2.17.0](/cpp/docs/reference/common/2.17.0/classgoogle_1_1cloud_1_1ErrorInfo)\n- [2.16.0](/cpp/docs/reference/common/2.16.0/classgoogle_1_1cloud_1_1ErrorInfo)\n- [2.15.1](/cpp/docs/reference/common/2.15.1/classgoogle_1_1cloud_1_1ErrorInfo)\n- [2.14.0](/cpp/docs/reference/common/2.14.0/classgoogle_1_1cloud_1_1ErrorInfo)\n- [2.13.0](/cpp/docs/reference/common/2.13.0/classgoogle_1_1cloud_1_1ErrorInfo)\n- [2.12.0](/cpp/docs/reference/common/2.12.0/classgoogle_1_1cloud_1_1ErrorInfo)\n- [2.11.0](/cpp/docs/reference/common/2.11.0/classgoogle_1_1cloud_1_1ErrorInfo)\n- [2.10.1](/cpp/docs/reference/common/2.10.1/classgoogle_1_1cloud_1_1ErrorInfo) \nDescribes the cause of the error with structured details. \n\n###### See Also\n\n\u003chttps://cloud.google.com/apis/design/errors#error_info\u003e\n\nConstructors\n------------\n\n### ErrorInfo()\n\nDefault constructor. \nPost-condition: the [`reason()`](/cpp/docs/reference/common/2.35.0/classgoogle_1_1cloud_1_1ErrorInfo#classgoogle_1_1cloud_1_1ErrorInfo_1a9c68904d153cbec3d48191568939fcf4), [`domain()`](/cpp/docs/reference/common/2.35.0/classgoogle_1_1cloud_1_1ErrorInfo#classgoogle_1_1cloud_1_1ErrorInfo_1a88e1355f82c33848c93660dc2759a816), and [`metadata()`](/cpp/docs/reference/common/2.35.0/classgoogle_1_1cloud_1_1ErrorInfo#classgoogle_1_1cloud_1_1ErrorInfo_1a638bbabb8dc7cd51d5dda6db8cee5a16) fields are empty.\n\n### ErrorInfo(std::string, std::string, std::unordered_map\\\u003c std::string, std::string \\\u003e)\n\nConstructor.\n\nFunctions\n---------\n\n### reason() const\n\nThe reason of the error. \nThis is a constant value that identifies the proximate cause of the error. Error reasons are unique within a particular domain of errors. This should be at most 63 characters and match a regular expression of `[A-Z][A-Z0-9_]+[A-Z0-9]`, which represents UPPER_SNAKE_CASE.\n\n### domain() const\n\nThe logical grouping to which the \"reason\" belongs. \nThe error domain is typically the registered service name of the tool or product that generates the error. Example: \"pubsub.googleapis.com\". If the error is generated by some common infrastructure, the error domain must be a globally unique value that identifies the infrastructure. For Google API infrastructure, the error domain is \"googleapis.com\".\n\nFor errors generated by the C++ client libraries the domain is `gcloud-cpp`.\n\n### metadata() const\n\nAdditional structured details about this error. \nKeys should match the regular expression `[a-zA-Z0-9-_]` and be limited to 64 characters in length.\n\nWhen identifying the current value of an exceeded limit, the units should be contained in the key, not the value. For example, if the client exceeds the number of instances that can be created in a single (batch) request return `{\"instanceLimitPerRequest\": \"100\"}` rather than `{\"instanceLimit\": \"100/request\"}`."]]
