--Config-file is loaded as a path, not a direct file when calling Viper - leading to implicit (undocumented) file prioritization of config files in the same path

[Chickenhen]

When providing the --config-file switch to Cloud-SQL-Proxy; users can provide TOML, JSON, YAML extensions.
Expectation is specific file is chosen when provided on the command line.

When loading the file via VIPER; the extension is removed from the lookup; and only the filename used.

If users have multiple files with same name; but different extension in same directory - the file loaded will be based on internal viper prioritization; not the file listed by the user

cloud-sql-proxy/cmd/root.go

Lines 690 to 692 in 88a85ce

	// argument must be the name of config file without extension
	v.SetConfigName(noExt)
	v.AddConfigPath(filepath.Dir(c.conf.Filepath))

precedence is defined by order of declaration

https://github.com/spf13/viper/blob/528f7416c4b56a4948673984b190bf8713f0c3c4/viper.go#L268

Options to resolve either

• change documentation to indicate the file load preference
• load exact file specified by user and error if not available - v.SetConfigFile(c.conf.Filepath)
• raise a warning \ exception if multiple files within the path specified by user could be loaded

[kgala2]

Hi @Chickenhen, thanks for reporting this issue,

We will try to have this resolved in the next release. In the meantime, if you have a PR already in mind or would like to submit one to implement the fix you suggested, we would be happy to review it.

[enocom]

FYI this is a small fix. See GoogleCloudPlatform/alloydb-auth-proxy#914 for the AlloyDB fix.