README
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snakecharmer
Go package that helps to get Cobra and Viper work together
Documentation
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Index ¶
- type CharmingOption
- func WithCobraCommand(cmd *cobra.Command) CharmingOption
- func WithConfigFileBaseName(s string) CharmingOption
- func WithConfigFilePath(s string) CharmingOption
- func WithConfigFileType(s string) CharmingOption
- func WithDecoderConfigOption(opt viper.DecoderConfigOption) CharmingOption
- func WithEnvTagName(s string) CharmingOption
- func WithFieldTagName(s string) CharmingOption
- func WithFlagHelpTagName(s string) CharmingOption
- func WithIgnoreUntaggedFields(on bool) CharmingOption
- func WithResultStruct(rs interface{}) CharmingOption
- func WithViper(viper *viper.Viper) CharmingOption
- type SnakeCharmer
- func (sch *SnakeCharmer) AddFlags()
- func (sch *SnakeCharmer) ConfigFileBaseName() string
- func (sch *SnakeCharmer) ConfigFilePath() string
- func (sch *SnakeCharmer) ConfigFileType() string
- func (sch *SnakeCharmer) DecoderConfigOptions() []viper.DecoderConfigOption
- func (sch *SnakeCharmer) EnvTagName() string
- func (sch *SnakeCharmer) FieldTagName() string
- func (sch *SnakeCharmer) FlagHelpTagName() string
- func (sch *SnakeCharmer) IgnoreUntaggedFields() bool
- func (sch *SnakeCharmer) ResultStruct() interface{}
- func (sch *SnakeCharmer) Set(opts ...CharmingOption) error
- func (sch *SnakeCharmer) UnmarshalExact() (err error)
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
This section is empty.
Types ¶
type CharmingOption ¶
type CharmingOption func(*SnakeCharmer) error
CharmingOption represents Functional Options Pattern. See this article for details - https://dave.cheney.net/2014/10/17/functional-options-for-friendly-apis CharmingOption is a type for a function that accepts a pointer to an empty or minimal SnakeCharmer struct created in the constructor.
func WithCobraCommand ¶
func WithCobraCommand(cmd *cobra.Command) CharmingOption
WithCobraCommand sets the pointer to the cobra.Command instance REQUIRED
func WithConfigFileBaseName ¶
func WithConfigFileBaseName(s string) CharmingOption
WithConfigFileBaseName sets the base name of the config file (without extension) that will be passed to viper.SetConfigName(). REQUIRED in case of the config file path is a directory, otherwise ignored. This defaults to "config"
func WithConfigFilePath ¶
func WithConfigFilePath(s string) CharmingOption
WithConfigFilePath sets the config file path that will be passed to viper.AddConfigPath() if path is a directory, or to viper.SetConfigFile() if path is a file. This defaults to "", which means config file won't be used.
func WithConfigFileType ¶
func WithConfigFileType(s string) CharmingOption
WithConfigFileType sets the type that will be passed to viper.SetConfigType(). REQUIRED in case if the config file does not have the extension or if the config file extension is not in the list of supported extensions. See viper.SupportedExts for full list of supported extensions. This defaults to "yaml"
func WithDecoderConfigOption ¶
func WithDecoderConfigOption(opt viper.DecoderConfigOption) CharmingOption
WithDecoderConfigOption adds a viper.DecoderConfigOption that will be passed to viper.Unmarshal for configuring mapstructure.DecoderConfig options See https://pkgo.dev/github.com/spf13/[email protected]#DecoderConfigOption
func WithEnvTagName ¶
func WithEnvTagName(s string) CharmingOption
WithEnvTagName sets the tag name that snakecharmer reads for setting ENV var name. This defaults to "env"
func WithFieldTagName ¶
func WithFieldTagName(s string) CharmingOption
WithFieldTagName sets the tag name that snakecharmer reads for field names. This defaults to "mapstructure"
func WithFlagHelpTagName ¶
func WithFlagHelpTagName(s string) CharmingOption
WithFlagHelpTagName sets the tag name that snakecharmer reads for flag usage help. This defaults to "usage"
func WithIgnoreUntaggedFields ¶
func WithIgnoreUntaggedFields(on bool) CharmingOption
WithIgnoreUntaggedFields allows to ignore all struct fields without explicit fieldTagName, comparable to `mapstructure:"-"` as default behaviour. See WithFieldTagName
func WithResultStruct ¶
func WithResultStruct(rs interface{}) CharmingOption
WithResultStruct sets the pointer to the struct that will contain the decoded config parameters. REQUIRED NOTE: the struct must be initialized with default values which will be used as flags
func WithViper ¶
func WithViper(viper *viper.Viper) CharmingOption
WithViper sets the pointer to the viper.Viper instance This defaults to viper.New()
type SnakeCharmer ¶
type SnakeCharmer struct {
// contains filtered or unexported fields
}
SnakeCharmer helps to get Cobra and Viper work together. It uses a user defined Struct for reading field tags and default values. Please note, that the struct must be initialized (with the default values) before passing to the SnakeCharmer. It automatically creates flags and adds them to cobra PersistentFlags flagset. It also creates viper's config params, and sets their default values, binds viper's config param with a corresponding flag from the cobra flagset, binds viper's config param with a corresponding ENV var SnakeCharmer sets the following priority of values: 1. flags (if passed) 2. ENV variables (if env tag set) 3. config file (if used) 4. defaults (from user defined Struct)
func NewSnakeCharmer ¶
func NewSnakeCharmer(opts ...CharmingOption) (*SnakeCharmer, error)
NewSnakeCharmer creates a new snakecharmer instance. charmer, err = NewSnakeCharmer(
WithResultStruct(result),
WithFieldTagName("snakecharmer"),
WithViper(vpr),
WithCobraCommand(cmd),
WithConfigFilePath(defaultConfigFile),
WithConfigFileType("yaml"),
WithIgnoreUntaggedFields(true),
WithDecoderConfigOption(
func(dc *mapstructure.DecoderConfig) { dc.WeaklyTypedInput = true },
),
)
func (*SnakeCharmer) AddFlags ¶
func (sch *SnakeCharmer) AddFlags()
AddFlags creates flags from tags of a given Result Struct. Adds flags to cobra PersistentFlags flagset, creates viper's config param and sets default value (viper.SetDefault()), binds viper's config param with a corresponding flag from the cobra flagset, binds viper's config param with a corresponding ENV var
func (*SnakeCharmer) ConfigFileBaseName ¶
func (sch *SnakeCharmer) ConfigFileBaseName() string
ConfigFileBaseName returns the base name of the config file (without extension) that will be passed to viper.SetConfigName().
func (*SnakeCharmer) ConfigFilePath ¶
func (sch *SnakeCharmer) ConfigFilePath() string
ConfigFilePath returns the config file path that will be passed to viper.AddConfigPath() if path is a directory, viper.SetConfigFile() if path is a file.
func (*SnakeCharmer) ConfigFileType ¶
func (sch *SnakeCharmer) ConfigFileType() string
ConfigFileType returns the type that will be passed to viper.SetConfigType().
func (*SnakeCharmer) DecoderConfigOptions ¶
func (sch *SnakeCharmer) DecoderConfigOptions() []viper.DecoderConfigOption
DecoderConfigOptions returns the slice of viper.DecoderConfigOption that will be passed to viper.Unmarshal()
func (*SnakeCharmer) EnvTagName ¶
func (sch *SnakeCharmer) EnvTagName() string
EnvTagName returns the tag name that snakecharmer reads for ENV var names.
func (*SnakeCharmer) FieldTagName ¶
func (sch *SnakeCharmer) FieldTagName() string
FieldTagName returns the tag name that snakecharmer reads for field names.
func (*SnakeCharmer) FlagHelpTagName ¶
func (sch *SnakeCharmer) FlagHelpTagName() string
FlagHelpTagName returns the tag name that snakecharmer reads for flag usage help.
func (*SnakeCharmer) IgnoreUntaggedFields ¶
func (sch *SnakeCharmer) IgnoreUntaggedFields() bool
IgnoreUntaggedFields returns the SnakeCharmer.ignoreUntaggedFields value that will be passed as viper.DecoderConfigOption
func (*SnakeCharmer) ResultStruct ¶
func (sch *SnakeCharmer) ResultStruct() interface{}
ResultStruct returns the pointer to the struct that contains the decoded values.
func (*SnakeCharmer) Set ¶
func (sch *SnakeCharmer) Set(opts ...CharmingOption) error
Set sets the snakecharmer options
func (*SnakeCharmer) UnmarshalExact ¶
func (sch *SnakeCharmer) UnmarshalExact() (err error)
UnmarshalExact unmarshals the config into a Struct, erroring if a field is nonexistent in the destination struct.
Source Files