NE_REQUEST_CREATE

Section: neon API reference (3)
Updated: 20 June 2020
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NAME

ne_request_create, ne_request_dispatch, ne_request_destroy - low-level HTTP request handling

SYNOPSIS

#include <ne_request.h>

ne_request *ne_request_create(ne_session *session, const char *method, const char *path);
int ne_request_dispatch(ne_request *req);
void ne_request_destroy(ne_request *req);

DESCRIPTION

The ne_request object represents an HTTP request and the associated response. The ne_request_create function creates a new request object for the given session. The target resource for the request is identified by the path, and the method to be performed on that resource via the method parameter.

The path string used must conform to the abs_path definition given in RFC2396, with an optional "?query" part, and must be URI-escaped by the caller (for instance, using ne_path_escape). If the string comes from an untrusted source, failure to perform URI-escaping results in a security vulnerability.

To dispatch a request, and process the response, the ne_request_dispatch function can be used. An alternative is to use the (more complex, but more flexible) combination of the ne_begin_request, ne_end_request, and ne_read_response_block functions; see ne_begin_request.

To add extra headers in the request, the functions ne_add_request_header and ne_print_request_header can be used. To include a message body with the request, one of the functions ne_set_request_body_buffer, ne_set_request_body_fd, or ne_set_request_body_provider can be used.

The return value of ne_request_dispatch indicates merely whether the request was sent and the response read successfully. To discover the result of the operation, ne_get_status, along with any processing of the response headers and message body.

A request can only be dispatched once: calling ne_request_dispatch more than once on a single ne_request object produces undefined behaviour. Once all processing associated with the request object is complete, use the ne_request_destroy function to destroy the resources associated with it. Any subsequent use of the request object produces undefined behaviour.

If a request is being using a non-idempotent method such as POST, the NE_REQFLAG_IDEMPOTENT flag should be disabled; see ne_set_request_flag.

RETURN VALUE

The ne_request_create function returns a pointer to a request object (and never NULL).

The ne_request_dispatch function returns zero if the request was dispatched successfully, and a non-zero error code otherwise.

ERRORS

NE_ERROR

: Request failed (see session error string)

NE_LOOKUP

: The DNS lookup for the server (or proxy server) failed.

NE_AUTH

: Authentication failed on the server.

NE_PROXYAUTH

: Authentication failed on the proxy server.

NE_CONNECT

: A connection to the server could not be established.

NE_TIMEOUT

: A timeout occurred while waiting for the server to respond.

EXAMPLE

An example of applying a MKCOL operation to the resource at the location http://www.example.com/foo/bar/:

ne_session *sess = ne_session_create("http", "www.example.com", 80);
ne_request *req = ne_request_create(sess, "MKCOL", "/foo/bar/");
if (ne_request_dispatch(req)) {
   printf("Request failed: %s\n", ne_get_error(sess));
}
ne_request_destroy(req);

AUTHOR

Joe Orton <neon@lists.manyfish.co.uk>

: Author.