config

type ClientConfig struct {
	// MaxHeaderListSize is the http2 SETTINGS_MAX_HEADER_LIST_SIZE to
	// send in the initial settings frame. It is how many bytes
	// of response headers are allowed. Unlike the http2 spec, zero here
	// means to use a default limit (currently 10MB). If you actually
	// want to advertise an unlimited value to the peer, Transport
	// interprets the highest possible value here (0xffffffff or 1<<32-1)
	// to mean no limit.
	MaxHeaderListSize uint32

	// AllowHTTP, if true, permits HTTP/2 requests using the insecure,
	// plain-text "http" scheme. Note that this does not enable h2c support.
	AllowHTTP bool

	// ReadIdleTimeout is the timeout after which a health check using ping
	// frame will be carried out if no frame is received on the connection.
	// Note that a ping response will is considered a received frame, so if
	// there is no other traffic on the connection, the health check will
	// be performed every ReadIdleTimeout interval.
	// If zero, no health check is performed.
	ReadIdleTimeout time.Duration

	// PingTimeout is the timeout after which the connection will be closed
	// if a response to Ping is not received.
	// Defaults to 15s.
	PingTimeout time.Duration

	// WriteByteTimeout is the timeout after which the connection will be
	// closed no data can be written to it. The timeout begins when data is
	// available to write, and is extended whenever any bytes are written.
	WriteByteTimeout time.Duration

	// StrictMaxConcurrentStreams controls whether the server's
	// SETTINGS_MAX_CONCURRENT_STREAMS should be respected
	// globally. If false, new TCP connections are created to the
	// server as needed to keep each under the per-connection
	// SETTINGS_MAX_CONCURRENT_STREAMS limit. If true, the
	// server's SETTINGS_MAX_CONCURRENT_STREAMS is interpreted as
	// a global limit and callers of RoundTrip block when needed,
	// waiting for their turn.
	StrictMaxConcurrentStreams bool

	// Default Dialer is used if not set.
	Dialer network.Dialer

	// Timeout for establishing new connections to hosts.
	//
	// Default DialTimeout is used if not set.
	DialTimeout time.Duration

	// Whether to use TLS (aka SSL or HTTPS) for host connections.
	// Optional TLS config.
	TLSConfig *tls.Config

	// Idle keep-alive connections are closed after this duration.
	//
	// By default idle connections are closed
	// after DefaultMaxIdleConnDuration.
	MaxIdleConnDuration time.Duration

	// All configurations related to retry
	RetryConfig *retry.Config

	// RetryIf controls whether a retry should be attempted after an error.
	//
	// By default will use isIdempotent function
	RetryIf client.RetryIfFunc

	// Connection will close after each request when set this to true.
	DisableKeepAlive bool
}

type ClientOption struct {
	F func(o *ClientConfig)
}

type Config struct {
	DisableKeepalive bool
	EnableTrace      bool
	ReadTimeout      time.Duration

	// MaxHandlers limits the number of http.Handler ServeHTTP goroutines
	// which may run at a time over all connections.
	// Negative or zero no limit.
	// TODO: implement
	MaxHandlers int

	// MaxConcurrentStreams optionally specifies the number of
	// concurrent streams that each client may have open at a
	// time. This is unrelated to the number of http.Handler goroutines
	// which may be active globally, which is MaxHandlers.
	// If zero, MaxConcurrentStreams defaults to at least 100, per
	// the HTTP/2 spec's recommendations.
	MaxConcurrentStreams uint32

	// MaxReadFrameSize optionally specifies the largest frame
	// this server is willing to read. A valid value is between
	// 16k and 16M, inclusive. If zero or otherwise invalid, a
	// default value is used.
	MaxReadFrameSize uint32

	// PermitProhibitedCipherSuites, if true, permits the use of
	// cipher suites prohibited by the HTTP/2 spec.
	PermitProhibitedCipherSuites bool

	// IdleTimeout specifies how long until idle clients should be
	// closed with a GOAWAY frame. PING frames are not considered
	// activity for the purposes of IdleTimeout.
	IdleTimeout time.Duration

	// MaxUploadBufferPerConnection is the size of the initial flow
	// control window for each connections. The HTTP/2 spec does not
	// allow this to be smaller than 65535 or larger than 2^32-1.
	// If the value is outside this range, a default value will be
	// used instead.
	MaxUploadBufferPerConnection int32

	// MaxUploadBufferPerStream is the size of the initial flow control
	// window for each stream. The HTTP/2 spec does not allow this to
	// be larger than 2^32-1. If the value is zero or larger than the
	// maximum, a default value will be used instead.
	MaxUploadBufferPerStream int32
}

type Option struct {
	F func(o *Config)
}