ne_session_create, ne_close_connection, ne_session_destroy — set up HTTP sessions
#include <ne_session.h>
ne_session *ne_session_create( | const char *scheme, |
const char *host, | |
unsigned int port) ; |
void ne_close_connection( | ne_session *session) ; |
void ne_session_destroy( | ne_session *session) ; |
An ne_session object represents an HTTP session - a logical grouping of a sequence of HTTP requests made to a certain server. Any requests made using the session can use a persistent connection, share cached authentication credentials and any other common attributes.
A new HTTP session is created using the
ne_session_create
function; the
host
and port
parameters specify the origin server to use, along with
the scheme
(usually "http"
).
Before the first use of ne_session_create
in a
process, ne_sock_init must have been called to
perform any global initialization needed by any libraries used by
neon.
To enable SSL/TLS for the session, pass the string
"https"
as the
scheme
, and either register a
certificate verification function (see ne_ssl_set_verify) or trust the appropriate
certificate (see ne_ssl_trust_cert, ne_ssl_trust_default_ca).
The host
parameter must follow
the definition of host host
in RFC 3986,
which can be an IP-literal or registered (DNS) hostname. Valid
examples of each: "198.51.100.42"
(IPv4
literal address), "[2001:db8::42]"
(IPv6
literal, which MUST be enclosed in square
brackets), or "www.example.com"
(DNS
hostname). The RFC 6874
syntax for scoped IPv6 link-local literal addresses is also
permitted, for example "[fe80::1%25eth0]"
.
The scheme
parameter is used to
determine the URI for resources identified during request
handling. Other than special handling of the string
"https"
, no other interpretation or
checking of the scheme
is
performed. For example, if an HTTP-to-FTP proxy is configured,
a scheme of "ftp"
could be used to access
resources.
To use a proxy server for the session, it must be configured (see ne_session_proxy) before any requests are created from session object.
Further per-session options may be changed using the ne_set_session_flag interface.
If it is known that the session will not be used for a
significant period of time, ne_close_connection
can be called to close the connection, if one remains open. Use of
this function is entirely optional, but it must not be called if there
is a request active using the session.
Once a session has been completed,
ne_session_destroy
must be called to
destroy the resources associated with the session. Any
subsequent use of the session pointer produces undefined
behaviour. The session object must not be destroyed until
after all associated request objects have been
destroyed.
If a hostname is passed to
ne_session_create
, it will be resolved when the first
request using the session is dispatched; a DNS resolution failure can
only be detected at that time (using the NE_LOOKUP
error code); see ne_request_dispatch for
details.