unidocs/org.http4s.client/Client

Client

trait Client[F[_]]

A Client submits Requests to a server and processes the Response.

When a connection is "released" and the HTTP semantics of the request and response permit, the connection may be kept alive by the backend and used for a subsequent request. When HTTP semantics require it, or at the backend's discretion, a released connection may also be closed.

Companion:
object
class Object
trait Matchable
class Any

Value members

Abstract methods

def expect[A](req: Request[F])(implicit d: EntityDecoder[F, A]): F[A]

Submits a request and decodes the response on success. On failure, the status code is returned. The underlying HTTP connection is released at the completion of the decoding.

Submits a request and decodes the response on success. On failure, the status code is returned. The underlying HTTP connection is released at the completion of the decoding.

def expect[A](req: F[Request[F]])(implicit d: EntityDecoder[F, A]): F[A]
def expect[A](uri: Uri)(implicit d: EntityDecoder[F, A]): F[A]

Submits a GET request to the specified URI and decodes the response on success. On failure, the status code is returned. The underlying HTTP connection is released at the completion of the decoding.

Submits a GET request to the specified URI and decodes the response on success. On failure, the status code is returned. The underlying HTTP connection is released at the completion of the decoding.

def expect[A](s: String)(implicit d: EntityDecoder[F, A]): F[A]

Submits a GET request to the URI specified by the String and decodes the response on success. On failure, the status code is returned. The underlying HTTP connection is released at the completion of the decoding.

Submits a GET request to the URI specified by the String and decodes the response on success. On failure, the status code is returned. The underlying HTTP connection is released at the completion of the decoding.

def expectOption[A](req: Request[F])(implicit d: EntityDecoder[F, A]): F[Option[A]]
def expectOptionOr[A](req: Request[F])(onError: Response[F] => F[Throwable])(implicit d: EntityDecoder[F, A]): F[Option[A]]
def expectOr[A](req: Request[F])(onError: Response[F] => F[Throwable])(implicit d: EntityDecoder[F, A]): F[A]
def expectOr[A](req: F[Request[F]])(onError: Response[F] => F[Throwable])(implicit d: EntityDecoder[F, A]): F[A]
def expectOr[A](uri: Uri)(onError: Response[F] => F[Throwable])(implicit d: EntityDecoder[F, A]): F[A]
def expectOr[A](s: String)(onError: Response[F] => F[Throwable])(implicit d: EntityDecoder[F, A]): F[A]
def fetchAs[A](req: Request[F])(implicit d: EntityDecoder[F, A]): F[A]

Submits a request and decodes the response, regardless of the status code. The underlying HTTP connection is released at the completion of the decoding.

Submits a request and decodes the response, regardless of the status code. The underlying HTTP connection is released at the completion of the decoding.

def fetchAs[A](req: F[Request[F]])(implicit d: EntityDecoder[F, A]): F[A]

Submits a request and decodes the response, regardless of the status code. The underlying HTTP connection is released at the completion of the decoding.

Submits a request and decodes the response, regardless of the status code. The underlying HTTP connection is released at the completion of the decoding.

def get[A](uri: Uri)(f: Response[F] => F[A]): F[A]

Submits a GET request, and provides a callback to process the response.

Submits a GET request, and provides a callback to process the response.

Value parameters:
f

A callback for the response to a GET on uri. The underlying HTTP connection is released when the returned task completes. Attempts to read the response body afterward will result in an error.

uri

The URI to GET

Returns:

The result of applying f to the response to req

def get[A](s: String)(f: Response[F] => F[A]): F[A]

Submits a request and decodes the response on success. On failure, the status code is returned. The underlying HTTP connection is released at the completion of the decoding.

Submits a request and decodes the response on success. On failure, the status code is returned. The underlying HTTP connection is released at the completion of the decoding.

def run(req: Request[F]): Resource[F, Response[F]]
def status(req: Request[F]): F[Status]

Submits a request and returns the response status

Submits a request and returns the response status

def status(req: F[Request[F]]): F[Status]

Submits a request and returns the response status

Submits a request and returns the response status

def statusFromString(s: String): F[Status]

Submits a GET request to the URI and returns the response status

Submits a GET request to the URI and returns the response status

def statusFromUri(uri: Uri): F[Status]

Submits a GET request to the URI and returns the response status

Submits a GET request to the URI and returns the response status

def stream(req: Request[F]): Stream[F, Response[F]]

Run the request as a stream. The response lifecycle is equivalent to the returned Stream's.

Run the request as a stream. The response lifecycle is equivalent to the returned Stream's.

def successful(req: Request[F]): F[Boolean]

Submits a request and returns true if and only if the response status is successful

Submits a request and returns true if and only if the response status is successful

def successful(req: F[Request[F]]): F[Boolean]

Submits a request and returns true if and only if the response status is successful

Submits a request and returns true if and only if the response status is successful

def toHttpApp: HttpApp[F]

Returns this client as an HttpApp. It is the responsibility of callers of this service to run the response body to release the underlying HTTP connection.

Returns this client as an HttpApp. It is the responsibility of callers of this service to run the response body to release the underlying HTTP connection.

This is intended for use in proxy servers. run, [[fetchAsA*]], toKleisli, and stream are safer alternatives, as their signatures guarantee release of the HTTP connection.

def toKleisli[A](f: Response[F] => F[A]): Kleisli[F, Request[F], A]

Returns this client as a cats.data.Kleisli. All connections created by this service are released on completion of callback task f.

Returns this client as a cats.data.Kleisli. All connections created by this service are released on completion of callback task f.

This method effectively reverses the arguments to run followed by use, and is preferred when an HTTP client is composed into a larger Kleisli function, or when a common response callback is used by many call sites.

Concrete methods

final def expectOptionOrT[A](req: Request[F])(onError: Response[F] => F[Throwable])(implicit d: EntityDecoder[F, A]): OptionT[F, A]

As expectOptionOr, but defined in terms of cats.data.OptionT.

As expectOptionOr, but defined in terms of cats.data.OptionT.

final def expectOptionT[A](req: Request[F])(implicit d: EntityDecoder[F, A]): OptionT[F, A]

As expectOption, but defined in terms of cats.data.OptionT.

As expectOption, but defined in terms of cats.data.OptionT.

def translate[G[_]](fk: FunctionK[F, G])(gK: FunctionK[G, F])(implicit F: MonadCancelThrow[F]): Client[G]

Translates the effect type of this client from F to G

Translates the effect type of this client from F to G

Deprecated methods

@deprecated("Use run(req).use(f)", "0.21.5")
def fetch[A](req: Request[F])(f: Response[F] => F[A]): F[A]

Submits a request, and provides a callback to process the response.

Submits a request, and provides a callback to process the response.

Value parameters:
f

A callback for the response to req. The underlying HTTP connection is released when the returned task completes. Attempts to read the response body afterward will result in an error.

req

The request to submit

Returns:

The result of applying f to the response to req

Deprecated
@deprecated("Use req.flatMap(run(_).use(f))", "0.21.5")
def fetch[A](req: F[Request[F]])(f: Response[F] => F[A]): F[A]

Submits a request, and provides a callback to process the response.

Submits a request, and provides a callback to process the response.

Value parameters:
f

A callback for the response to req. The underlying HTTP connection is released when the returned task completes. Attempts to read the response body afterward will result in an error.

req

An effect of the request to submit

Returns:

The result of applying f to the response to req

Deprecated