'\"macro stdmacro
.\"
.\" Copyright (c) 2016 Red Hat.
.\" 
.\" This program is free software; you can redistribute it and/or modify it
.\" under the terms of the GNU General Public License as published by the
.\" Free Software Foundation; either version 2 of the License, or (at your
.\" option) any later version.
.\" 
.\" This program is distributed in the hope that it will be useful, but
.\" WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
.\" or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
.\" for more details.
.\"
.TH PMHTTPNEWCLIENT 3 "PCP" "Performance Co-Pilot"
.SH NAME
\f3pmhttpNewClient\f1,
\f3pmhttpFreeClient\f1,
\f3pmhttpClientFetch\f1 \- simple HTTP client interfaces
.SH "C SYNOPSIS"
.ft 3
#include <pcp/pmapi.h>
.br
#include <pcp/pmhttp.h>
.sp
.ad l
.hy 0
.in +8n
.ti -8n
struct http_client *pmhttpNewClient(void);
.br
.ti -8n
void pmhttpFreeClient(struct http_client *\fIclient\fP);
.br
.ti -8n
int pmhttpClientFetch(struct http_client *\fIclient\fP, const char *\fIurl\fP, char *\fIbodybuf\fP, size_t \fIbodylen\fP, char *\fItypebuf\fP, size_t \fItypelen\fP);
.sp
.in
.hy
.ad
cc ... \-lpcp_web
.ft 1
.SH DESCRIPTION
.B pmhttpNewClient
allocates and initializes an opaque HTTP client that is ready to
make requests from a server.
.PP
The URL request interface
.B pmhttpClientFetch
issues an HTTP GET request to the server specified in the supplied
.IR url .
The body of the response is returned in the caller supplied
.I bodybuf
buffer, of
.I bodylen
bytes length.
An optional
.I typebuf
buffer, of
.I typelen
bytes length, can also be supplied and (if non-NULL) will contain the
value of the content-type header returned from the server.
.PP
The
.I url
parameter is an \f2RFC1630\f1 format URL.
This will typically be prefixed with "http://", however these interfaces
also support Unix domain sockets.
Those are instead prefixed by "unix://", followed by the full filesystem
path to the desired Unix domain socket.
.PP
To free up resources associated with an HTTP client, including closing
any persistent server connection that has been established earlier, is
accomplished using the
.B pmhttpFreeClient
routine.
.SH DIAGNOSTICS
.B pmhttpNewClient
will return NULL on failure, which can only occur when allocation
of memory is not possible.
.PP
.B pmhttpClientFetch
will return the number of bytes places into the
.I bodybuf
buffer, else a negated error code indicating the nature of the failure.
.SH SEE ALSO
.BR pmdaapache (1),
.BR pmjsonInit (3),
.BR PMAPI (3),
.BR PMWEBAPI (3)
and
.hy
.nh
.BR https://tools.ietf.org/html/rfc1630 .
.hy