gcloud topic flags-file - --flags-file=YAML_FILE supplementary help

Complex flag values that contain command interpreter special characters may bedifficult to specify on the command line. The combined list ofspecial characters across commonly used commandinterpreters (shell, cmd.exe, PowerShell) is surprisingly large. Among them are", ', `, *, ?, [, ], (, ), $, %, #, ^, &, |, {, }, ;, \, <,>,space,tab,newline. Add to that the separator characters forlist anddict valued flags, and it becomes all butimpossible to construct portable command lines.

The--flags-file=YAML-FILE flag solves thisproblem by allowing command line flags to be specified in a YAML/JSON file.String, numeric, list and dict flag values are specified using YAML/JSONnotation and quoting rules.

Flag specification uses dictionary notation. Use a list of dictionaries forflags that must be specified multiple times.

For example, this YAML file defines values for Boolean, integer, floating point,string, dictionary and list valued flags:

--boolean:--integer:123--float:456.789--string:A string value.--dictionary:a=b:c,de,f:g=hi:nonej=k=l:m=$n,o=%p"y:":":z"meta:-key:foovalue:bar-key:abcvalue:xyz--list:-a,b,c-x,y,z

If the file is namedmy-flags.yaml then the command line flag--flags-file=my-flags.yaml will set the specified flags on anysystem using any command interpreter.--flags-file may be specifiedin a YAML file, and its value can be a YAML list to reference multiple files.

This example specifies the--metadata flag multiple times:

---metadata:abc--integer:123---metadata:xyz

Each--flags-file arg is replaced by its contents, so normal flagprecedence applies. For example, givenflags-1.yaml:

--zone:us-east2-a

flags-2.yaml:

--verbosity:info--zone:us-central1-a

and command line:

gcloudcomputeinstancesdescribe\--flags-file=flags-1.yamlmy-instance--flags-file=flags-2.yaml

the effective command line is:

gcloudcomputeinstancesdescribe\--zone=us-east2-amy-instance--verbosity=info--zone=us-central1-a

using zoneus-central1-a (notus-east2-a, becauseflags-2.yaml, to the right offlags-1.yaml, has higherprecedence).