config

type Config struct {
	// Addr is the TCP address the HTTP API listens on, "host:port" with a
	// numeric port; an empty host means every interface.
	Addr string

	// LogLevel is the minimum level written to the log.
	LogLevel slog.Level

	// LogKey is the HMAC key that pseudonymises personal data in the log.
	LogKey Secret

	// DataDir is the only directory the commands write to: the data
	// volume. Every other path may be read-only.
	DataDir string

	// SourceACPR turns the ACPR blacklist on, once its reuse licence is
	// obtained.
	SourceACPR bool

	// AlertWebhook is the HTTPS URL a failed or rejected sync is posted
	// to; nil when unset or empty, and then alerts are only logged. It is a
	// Secret: a webhook URL usually carries its credential.
	AlertWebhook Secret

	// ProblemBaseURL is the HTTPS URL of the documentation of the API's
	// problems, ending with a slash: the type of a problem is its code
	// under it.
	ProblemBaseURL string

	// BatchMaxItems is the most items POST /v1/check/batch accepts, from 1
	// to MaxBatchMaxItems.
	BatchMaxItems int

	// DatabaseURL is the PostgreSQL connection string of the API key store;
	// nil when unset or empty. RequireKeyStore tells whether it is set.
	DatabaseURL Secret

	// APIKeySecret is the HMAC key the API keys are digested with, kept
	// out of the database; nil when unset or empty.
	APIKeySecret Secret

	// APIKeyEnv is the environment of the API keys accepted: "live" or
	// "test".
	APIKeyEnv string

	// RateLimitKey is the number of requests per minute of an API key,
	// from 1 to MaxRateLimit.
	RateLimitKey int

	// RateLimitIP is the number of requests per minute of a client address
	// on the routes needing no key, from 1 to MaxRateLimit.
	RateLimitIP int

	// RateLimitAuth is the number of refused API keys per minute of a
	// client address on the check routes, from 1 to MaxRateLimit: over it,
	// its keys are no longer looked up.
	RateLimitAuth int

	// TrustedProxies are the proxies whose X-Forwarded-For field tells the
	// client's address: nil when unset, empty when set to "none".
	// RequireTrustedProxies tells whether it is set.
	TrustedProxies []netip.Prefix
}

type Secret []byte