Warning: This is the manual of the legacy Guile 2.0 series. You may want to read the manual of the current stable series instead.
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(web client)
provides a simple, synchronous HTTP client, built on
the lower-level HTTP, request, and response modules.
(use-modules (web client))
Return an open input/output port for a connection to URI.
Connect to the server corresponding to uri and make a request over
HTTP, using the appropriate method (GET
, HEAD
, etc.).
All of these procedures have the same prototype: a URI followed by an optional sequence of keyword arguments. These keyword arguments allow you to modify the requests in various ways, for example attaching a body to the request, or setting specific headers. The following table lists the keyword arguments and their default values.
#:body #f
#:port (open-socket-for-uri uri)]
#:version '(1 . 1)
#:keep-alive? #f
#:headers '()
#:decode-body? #t
#:streaming? #f
If you already have a port open, pass it as port. Otherwise, a connection will be opened to the server corresponding to uri. Any extra headers in the alist headers will be added to the request.
If body is not #f
, a message body will also be sent with
the HTTP request. If body is a string, it is encoded according to
the content-type in headers, defaulting to UTF-8. Otherwise
body should be a bytevector, or #f
for no body. Although a
message body may be sent with any request, usually only POST
and
PUT
requests have bodies.
If decode-body? is true, as is the default, the body of the response will be decoded to string, if it is a textual content-type. Otherwise it will be returned as a bytevector.
However, if streaming? is true, instead of eagerly reading the response body from the server, this function only reads off the headers. The response body will be returned as a port on which the data may be read.
Unless keep-alive? is true, the port will be closed after the full response body has been read.
Returns two values: the response read from the server, and the response body as a string, bytevector, #f value, or as a port (if streaming? is true).
http-get
is useful for making one-off requests to web sites. If
you are writing a web spider or some other client that needs to handle a
number of requests in parallel, it’s better to build an event-driven URL
fetcher, similar in structure to the web server (see Web Server).
Another option, good but not as performant, would be to use threads, possibly via par-map or futures.
Either #f
or a non-empty string containing the URL of the HTTP
proxy server to be used by the procedures in the (web client)
module, including open-socket-for-uri
. Its initial value is
based on the http_proxy
environment variable.
(current-http-proxy) ⇒ "http://localhost:8123/" (parameterize ((current-http-proxy #f)) (http-get "http://example.com/")) ; temporarily bypass proxy (current-http-proxy) ⇒ "http://localhost:8123/"
Next: Web Server, Previous: Responses, Up: Web [Contents][Index]