Protocol::HTTP2::Client − HTTP/2 client
use
Protocol::HTTP2::Client;
# Create client object
my $client = Protocol::HTTP2::Client−>new;
# Prepare first request
$client−>request(
# HTTP/2 headers
':scheme' => 'http',
':authority' => 'localhost:8000',
':path' => '/',
':method' => 'GET',
# HTTP/1.1 headers
headers => [
'accept' => '*/*',
'user−agent' =>
'perl−Protocol−HTTP2/0.13',
],
# Callback when receive server's response
on_done => sub {
my ( $headers, $data ) = @_;
...
},
);
# Protocol::HTTP2 is just HTTP/2 protocol decoder/encoder
# so you must create connection yourself
use AnyEvent;
use AnyEvent::Socket;
use AnyEvent::Handle;
my $w = AnyEvent−>condvar;
# Plain−text HTTP/2 connection
tcp_connect 'localhost', 8000, sub {
my ($fh) = @_ or die "connection failed: $!\n";
my $handle;
$handle = AnyEvent::Handle−>new(
fh => $fh,
autocork => 1,
on_error => sub {
$_[0]−>destroy;
print "connection error\n";
$w−>send;
},
on_eof => sub {
$handle−>destroy;
$w−>send;
}
);
# First write preface to peer
while ( my $frame = $client−>next_frame ) {
$handle−>push_write($frame);
}
# Receive servers frames
# Reply to server
$handle−>on_read(
sub {
my $handle = shift;
$client−>feed( $handle−>{rbuf} );
$handle−>{rbuf} = undef;
while ( my $frame = $client−>next_frame ) {
$handle−>push_write($frame);
}
# Terminate connection if all done
$handle−>push_shutdown if
$client−>shutdown;
}
);
};
$w−>recv;
Protocol::HTTP2::Client is HTTP/2 client library. It’s intended to make http2−client implementations on top of your favorite event-loop.
new
Initialize new client object
my $client = Procotol::HTTP2::Client−>new( %options );
Available
options:
on_push => sub {...}
If server send push promise this callback will be invoked
on_push =>
sub {
# received PUSH PROMISE headers
my $pp_header = shift;
...
# if we want reject this push
# return undef
# if we want to accept pushed resource
# return callback to receive data
return sub {
my ( $headers, $data ) = @_;
...
}
},
upgrade => 0|1
Use HTTP/1.1 Upgrade to upgrade protocol from HTTP/1.1 to HTTP/2. Upgrade possible only on plain (non-tls) connection. Default value is 0.
See Starting HTTP/2 for "http" URIs <https://tools.ietf.org/html/rfc7540#section-3.2>
keepalive => 0|1
Keep connection alive after requests. Default value is 0. Don’t forget to explicitly call close method if set this to true.
on_error => sub {...}
Callback invoked on protocol errors
on_error =>
sub {
my $error = shift;
...
},
on_change_state => sub {...}
Callback invoked every time when http/2 streams change their state. See Stream States <https://tools.ietf.org/html/rfc7540#section-5.1>
on_change_state
=> sub {
my ( $stream_id, $previous_state, $current_state ) = @_;
...
},
request
Prepare HTTP/2 request.
$client−>request(
# HTTP/2 headers
':scheme' => 'http',
':authority' => 'localhost:8000',
':path' => '/items',
':method' => 'POST',
# HTTP/1.1 headers
headers => [
'content−type' =>
'application/x−www−form−urlencoded',
'user−agent' =>
'perl−Protocol−HTTP2/0.06',
],
# Callback when receive server's response
on_done => sub {
my ( $headers, $data ) = @_;
...
},
# Callback when receive stream reset
on_error => sub {
my $error_code = shift;
},
# Body of POST request
data => "hello=world&test=done",
);
You can chaining request one by one:
$client−>request( 1−st request )−>request( 2−nd request );
Available
callbacks:
on_done => sub {...}
Invoked when full servers response is available
on_done =>
sub {
my ( $headers, $data ) = @_;
...
},
on_headers => sub {...}
Invoked as soon as headers have been successfully received from the server
on_headers
=> sub {
my $headers = shift;
...
# if we want reject any data
# return undef
# continue
return 1
}
on_data => sub {...}
If specified all data will be passed to this callback instead if on_done. on_done will receive empty string.
on_data =>
sub {
my ( $partial_data, $headers ) = @_;
...
# if we want cancel download
# return undef
# continue downloading
return 1
}
on_error => sub {...}
Callback invoked on stream errors
on_error =>
sub {
my $error = shift;
...
}
keepalive
Keep connection alive after requests
my $bool =
$client−>keepalive;
$client = $client−>keepalive($bool);
shutdown
Get connection
status:
0 − active
1 − closed (you can terminate connection)
close
Explicitly close connection (send GOAWAY frame). This is required if client has keepalive option enabled.
next_frame
get next frame
to send over connection to server. Returns:
undef − on error
0 − nothing to send
binary string − encoded frame
# Example
while ( my $frame = $client−>next_frame ) {
syswrite $fh, $frame;
}
feed
Feed decoder with chunks of server’s response
sysread $fh,
$binary_data, 4096;
$client−>feed($binary_data);
ping
Send ping frame to server (to keep connection alive)
$client−>ping
or
$client−>ping($payload);
Payload can be arbitrary binary string and must contain 8 octets. If payload argument is omitted client will send random data.