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type Config struct {
	CRLUpdater struct {
		DebugAddr string `validate:"omitempty,hostname_port"`

		// TLS client certificate, private key, and trusted root bundle.
		TLS cmd.TLSConfig

		SAService           *cmd.GRPCClientConfig
		CRLGeneratorService *cmd.GRPCClientConfig
		CRLStorerService    *cmd.GRPCClientConfig

		// IssuerCerts is a list of paths to issuer certificates on disk. This
		// controls the set of CRLs which will be published by this updater: it will
		// publish one set of NumShards CRL shards for each issuer in this list.
		IssuerCerts []string `validate:"min=1,dive,required"`

		// NumShards is the number of shards into which each issuer's "full and
		// complete" CRL will be split.
		// WARNING: When this number is changed, the "JSON Array of CRL URLs" field
		// in CCADB MUST be updated.
		NumShards int `validate:"min=1"`

		// ShardWidth is the amount of time (width on a timeline) that a single
		// shard should cover. Ideally, NumShards*ShardWidth should be an amount of
		// time noticeably larger than the current longest certificate lifetime,
		// but the updater will continue to work if this is not the case (albeit
		// with more confusing mappings of serials to shards).
		// WARNING: When this number is changed, revocation entries will move
		// between shards.
		ShardWidth config.Duration `validate:"-"`

		// LookbackPeriod is how far back the updater should look for revoked expired
		// certificates. We are required to include every revoked cert in at least
		// one CRL, even if it is revoked seconds before it expires, so this must
		// always be greater than the UpdatePeriod, and should be increased when
		// recovering from an outage to ensure continuity of coverage.
		LookbackPeriod config.Duration `validate:"-"`

		// UpdatePeriod controls how frequently the crl-updater runs and publishes
		// new versions of every CRL shard. The Baseline Requirements, Section 4.9.7:
		// "MUST update and publish a new CRL within twenty‐four (24) hours after
		// recording a Certificate as revoked."
		UpdatePeriod config.Duration

		// UpdateTimeout controls how long a single CRL shard is allowed to attempt
		// to update before being timed out. The total CRL updating process may take
		// significantly longer, since a full update cycle may consist of updating
		// many shards with varying degrees of parallelism. This value must be
		// strictly less than the UpdatePeriod. Defaults to 10 minutes, one order
		// of magnitude greater than our p99 update latency.
		UpdateTimeout config.Duration `validate:"-"`

		// MaxParallelism controls how many workers may be running in parallel.
		// A higher value reduces the total time necessary to update all CRL shards
		// that this updater is responsible for, but also increases the memory used
		// by this updater. Only relevant in -runOnce mode.
		MaxParallelism int `validate:"min=0"`

		// MaxAttempts control how many times the updater will attempt to generate
		// a single CRL shard. A higher number increases the likelihood of a fully
		// successful run, but also increases the worst-case runtime and db/network
		// load of said run. The default is 1.
		MaxAttempts int `validate:"omitempty,min=1"`

		// ExpiresMargin adds a small increment to the CRL's HTTP Expires time.
		//
		// When uploading a CRL, its Expires field in S3 is set to the expected time
		// the next CRL will be uploaded (by this instance). That allows our CDN
		// instances to cache for that long. However, since the next update might be
		// slow or delayed, we add a margin of error.
		//
		// Tradeoffs: A large ExpiresMargin reduces the chance that a CRL becomes
		// uncacheable and floods S3 with traffic (which might result in 503s while
		// S3 scales out).
		//
		// A small ExpiresMargin means revocations become visible sooner, including
		// admin-invoked revocations that may have a time requirement.
		ExpiresMargin config.Duration

		// CacheControl is a string passed verbatim to the crl-storer to store on
		// the S3 object.
		//
		// Note: if this header contains max-age, it will override
		// Expires. https://www.rfc-editor.org/rfc/rfc9111.html#name-calculating-freshness-lifet
		// Cache-Control: max-age has the disadvantage that it caches for a fixed
		// amount of time, regardless of how close the CRL is to replacement. So
		// if max-age is used, the worst-case time for a revocation to become visible
		// is UpdatePeriod + the value of max age.
		//
		// The stale-if-error and stale-while-revalidate headers may be useful here:
		// https://aws.amazon.com/about-aws/whats-new/2023/05/amazon-cloudfront-stale-while-revalidate-stale-if-error-cache-control-directives/
		//
		// https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Cache-Control
		CacheControl string

		Features features.Config
	}

	Syslog        cmd.SyslogConfig
	OpenTelemetry cmd.OpenTelemetryConfig
}