provider

type CLIProvider ¶

type CLIProvider struct {
	// contains filtered or unexported fields
}

CLIProvider exposes a pre-parsed map (typically built by the user from command-line flags) as the highest-priority static provider. Users wire it up in main() after their flag parsing completes — fastconf does not own the flag set.

func NewCLI(data map[string]any) *CLIProvider

func (p *CLIProvider) Load(_ context.Context) (map[string]any, error)

func (p *CLIProvider) Name() string

func (p *CLIProvider) Priority() int

func (p *CLIProvider) Watch(_ context.Context) (<-chan contracts.Event, error)

func (p *CLIProvider) WithPriority(prio int) *CLIProvider

type DotEnvProvider ¶

type DotEnvProvider struct {
	// contains filtered or unexported fields
}

DotEnvProvider reads one or more .env files and emits a nested map using the same key convention as EnvProvider: an optional prefix is stripped and "__" (double underscore) introduces a nesting level. Actual process environment variables take precedence over .env values for the same key, matching the classic dotenv contract.

Priority defaults to PriorityDotEnv (5), so all other built-in providers override dotenv values.

Supported .env syntax:

• KEY=VALUE (unquoted; trailing spaces trimmed)
• KEY="double quoted" (supports \n \t \" \\ escapes)
• KEY='single quoted' (no escapes; literal content)
• export KEY=VALUE (leading "export" keyword stripped)
• # comment lines
• Blank lines are ignored.

func NewDotEnv(prefix string, paths ...string) *DotEnvProvider

func (p *DotEnvProvider) Load(_ context.Context) (map[string]any, error)

func (p *DotEnvProvider) Name() string

func (p *DotEnvProvider) Priority() int

func (p *DotEnvProvider) Watch(_ context.Context) (<-chan contracts.Event, error)

func (p *DotEnvProvider) WithPriority(prio int) *DotEnvProvider

type EnvKeyReplacer ¶

type EnvKeyReplacer interface {
	Replace(s string) string
}

EnvKeyReplacer transforms the post-prefix portion of an env var name into a dotted-path string. Empty result means "skip this key".

var DotReplacer EnvKeyReplacer = EnvKeyReplacerFunc(func(s string) string {
	return strings.ToLower(strings.ReplaceAll(s, "_", "."))
})

APP_DATABASE_DSN, prefix="APP_" → "database.dsn"

type EnvKeyReplacerFunc ¶

type EnvKeyReplacerFunc func(string) string

EnvKeyReplacerFunc is an EnvKeyReplacer adapter for plain funcs.

func (f EnvKeyReplacerFunc) Replace(s string) string

type EnvProvider ¶

type EnvProvider struct {
	// contains filtered or unexported fields
}

EnvProvider reads process environment variables matching a prefix and translates them into a nested map. Conventions:

• Prefix is stripped.
• "__" (double underscore) introduces a nesting level. Single underscore is preserved as part of the key (handles names like APP_FEATURE_FLAGS).
• Keys are lower-cased.
• Values are coerced to bool / int64 / float64 / string in that order.

Example: APP_DATABASE__POOL=20 with prefix "APP_" produces {"database":{"pool":int64(20)}}.

func NewEnv(prefix string) *EnvProvider

func (p *EnvProvider) Load(_ context.Context) (map[string]any, error)

func (p *EnvProvider) Name() string

func (p *EnvProvider) Priority() int

func (p *EnvProvider) Watch(_ context.Context) (<-chan contracts.Event, error)

func (p *EnvProvider) WithPriority(prio int) *EnvProvider

type LabelOptions ¶

type LabelOptions struct {
	// Name overrides the default Provider name (otherwise "labels:<prefix>"
	// or "labels:" when prefix is empty).
	Name string
	// Priority sets the merge priority. Defaults to PriorityCLI so labels
	// from a controller / docker engine override file layers.
	Priority int
	// Prefix, when non-empty, restricts expansion to labels whose key starts
	// with this prefix (e.g. "traefik.").
	Prefix string
	// StripPrefix removes Prefix from each key before expansion.
	StripPrefix bool
	// Separator splits a flat key into nested segments. Default ".".
	Separator string
	// Coerce, when true, converts "true"/"false"/int/float strings into typed
	// values. Default false: values are kept verbatim (matches Traefik /
	// Compose label semantics).
	Coerce bool
}

LabelOptions configures a LabelProvider. Mirrors mappath.LabelOptions so callers do not need to import two packages.

type LabelProvider ¶

type LabelProvider struct {
	// contains filtered or unexported fields
}

LabelProvider injects a flat list (or map) of Traefik / Docker / K8s style dotted labels as a single configuration layer. Use it when labels arrive from outside the configuration file — e.g. a Docker engine query, a K8s controller scanning service annotations, or a CLI flag with --label.

LabelProvider is read-only and does not implement Watch; pair it with a fastconf.Reload(ctx) call when the upstream label set changes.

func NewLabelMap(labels map[string]string, opts LabelOptions) *LabelProvider

func NewLabels(labels []string, opts LabelOptions) *LabelProvider

func (p *LabelProvider) Load(_ context.Context) (map[string]any, error)

func (p *LabelProvider) Name() string

func (p *LabelProvider) Priority() int

func (p *LabelProvider) Watch(_ context.Context) (<-chan contracts.Event, error)

type ReplacerProvider ¶

type ReplacerProvider struct {
	// contains filtered or unexported fields
}

ReplacerProvider is an EnvProvider variant that routes the post-prefix portion of each env name through Replacer before building the nested map. Value coercion (bool / int / float / string) is identical to EnvProvider.

func NewEnvReplacer(prefix string, replacer EnvKeyReplacer) *ReplacerProvider

func (p *ReplacerProvider) Load(_ context.Context) (map[string]any, error)

func (p *ReplacerProvider) Name() string

func (p *ReplacerProvider) Priority() int

func (p *ReplacerProvider) Watch(_ context.Context) (<-chan contracts.Event, error)

func (p *ReplacerProvider) WithPriority(prio int) *ReplacerProvider