Represents a textual expression in the Common Expression Language (CEL) syntax. CEL is a C-like expression language. The syntax and semantics of CEL are documented athttps://github.com/google/cel-spec.
Example (Comparison):
title: "Summary size limit"
description: "Determines if a summary is less than 100 chars"
expression: "document.summary.size() < 100"
Example (Equality):
title: "Requestor is owner"
description: "Determines if requestor is the document owner"
expression: "document.owner == request.auth.claims.email"
Example (Logic):
title: "Public documents"
description: "Determine whether the document should be publicly visible"
expression: "document.type != 'private' && document.type != 'internal'"
Example (Data Manipulation):
title: "Notification string"
description: "Create a notification string with a timestamp."
expression: "'New message received at ' + string(document.create_time)"
The exact variables and functions that may be referenced within an expression are determined by the service that evaluates it. See the service documentation for additional information.
Fields
expression
string
Textual representation of an expression in Common Expression Language syntax.
title
string
Optional. Title for the expression, i.e. a short string describing its purpose. This can be used e.g. in UIs which allow to enter the expression.
description
string
Optional. Description of the expression. This is a longer text which describes the expression, e.g. when hovered over it in a UI.
location
string
Optional. String indicating the location of the expression for error reporting, e.g. a file name and a position in the file.
[[["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 2025-08-07 UTC."],[[["\u003cp\u003eThe \u003ccode\u003eExpr\u003c/code\u003e message represents a textual expression written in the Common Expression Language (CEL) syntax, which is a C-like language documented at \u003ca href=\"https://github.com/google/cel-spec\"\u003ehttps://github.com/google/cel-spec\u003c/a\u003e.\u003c/p\u003e\n"],["\u003cp\u003e\u003ccode\u003eExpr\u003c/code\u003e expressions can be used for various purposes, including comparisons, equality checks, logical operations, and data manipulation, as demonstrated in the provided examples.\u003c/p\u003e\n"],["\u003cp\u003eEach \u003ccode\u003eExpr\u003c/code\u003e contains an \u003ccode\u003eexpression\u003c/code\u003e field, a textual representation of the expression itself, along with optional \u003ccode\u003etitle\u003c/code\u003e and \u003ccode\u003edescription\u003c/code\u003e fields to provide context, and \u003ccode\u003elocation\u003c/code\u003e for error reporting.\u003c/p\u003e\n"],["\u003cp\u003eThe specific variables and functions available for use within an \u003ccode\u003eExpr\u003c/code\u003e are defined by the service evaluating the expression.\u003c/p\u003e\n"],["\u003cp\u003eThe provided examples illustrate how to formulate expressions for tasks such as comparing document summary sizes, checking user ownership, determining document visibility, and creating dynamic notification strings.\u003c/p\u003e\n"]]],[],null,["# Package google.type\n\nIndex\n-----\n\n- [DayOfWeek](/backup-disaster-recovery/docs/reference/rpc/google.type#google.type.DayOfWeek) (enum)\n- [Expr](/backup-disaster-recovery/docs/reference/rpc/google.type#google.type.Expr) (message)\n- [Month](/backup-disaster-recovery/docs/reference/rpc/google.type#google.type.Month) (enum)\n\nDayOfWeek\n---------\n\nRepresents a day of the week.\n\nExpr\n----\n\nRepresents a textual expression in the Common Expression Language (CEL) syntax. CEL is a C-like expression language. The syntax and semantics of CEL are documented at \u003chttps://github.com/google/cel-spec\u003e.\n\nExample (Comparison): \n\n title: \"Summary size limit\"\n description: \"Determines if a summary is less than 100 chars\"\n expression: \"document.summary.size() \u003c 100\"\n\nExample (Equality): \n\n title: \"Requestor is owner\"\n description: \"Determines if requestor is the document owner\"\n expression: \"document.owner == request.auth.claims.email\"\n\nExample (Logic): \n\n title: \"Public documents\"\n description: \"Determine whether the document should be publicly visible\"\n expression: \"document.type != 'private' && document.type != 'internal'\"\n\nExample (Data Manipulation): \n\n title: \"Notification string\"\n description: \"Create a notification string with a timestamp.\"\n expression: \"'New message received at ' + string(document.create_time)\"\n\nThe exact variables and functions that may be referenced within an expression are determined by the service that evaluates it. See the service documentation for additional information.\n\nMonth\n-----\n\nRepresents a month in the Gregorian calendar."]]
