Configuration

Every field is optional.

w, err := wardn.New(wardn.Config{ /* ... */ })
w := wardn.MustNew(wardn.Config{ /* ... */ }) // panics on error; for main()

Field	Type	Default	Purpose
File	string	"wardn.yaml"	Path of the policy file.
Policy	*Policy	—	A policy defined in Go, used instead of File.
Store	Store	in-memory	Where assignments, custom roles and links live. See Choosing a store.
ManualMigrations	bool	false	Don’t migrate the store at startup; your pipeline does it.
ParentOf	func(ctx, Scope) (Scope, bool, error)	stored links	Resolve scope parents from your own data.
UserFrom	func(*http.Request) (string, bool)	the context	Where middleware finds the signed-in user.
OnError	func(http.ResponseWriter, *http.Request, error)	generic JSON	How middleware writes 401/403/400/500 responses.
OnDecision	func(ctx, Decision, error)	—	Called with every decision.
OnChange	func(ctx, Event) error	—	Called before every change; an error stops the change.
Clock	Clock	system clock	The time source for time-limited access.
Cache	Cache	none	A cross-request cache. See Caching.
CacheSecret	[]byte	random, for the memory cache only	Signs cache entries. Required (32+ bytes) for a shared cache.
CacheTTL	time.Duration	5s (max 5m)	Lifetime of cache entries.

Startup checks

New returns an error (and MustNew panics) if:

• the policy is invalid
• both File and Policy are set
• the store’s migration fails, or the database was upgraded by a newer wardn
• a shared cache has no CacheSecret, or the secret is under 32 bytes
• CacheTTL is negative or over five minutes

A misconfigured application never starts.

Limits

Limit	Value
User and scope IDs	256 bytes; no control or invisible characters, no leading or trailing whitespace
Scope type and system role names	64 characters
Permission names	128 characters
Descriptions	512 bytes
Policy file	1 MiB
Custom role names	64 characters
Permissions in one custom role	256
Custom roles per scope	500
Members page size	500
Assignment times	years 1–9999