Ubuntu Manpage: HTTP::Tiny - A small, simple, correct HTTP/1.1 client

Provided by: libhttp-tiny-perl_0.039-1_all

NAME

       HTTP::Tiny - A small, simple, correct HTTP/1.1 client

VERSION

       version 0.039

SYNOPSIS

           use HTTP::Tiny;

           my $response = HTTP::Tiny->new->get('http://example.com/');

           die "Failed!\n" unless $response->{success};

           print "$response->{status} $response->{reason}\n";

           while (my ($k, $v) = each %{$response->{headers}}) {
               for (ref $v eq 'ARRAY' ? @$v : $v) {
                   print "$k: $_\n";
               }
           }

           print $response->{content} if length $response->{content};

DESCRIPTION

       This is a very simple HTTP/1.1 client, designed for doing simple GET requests without the
       overhead of a large framework like LWP::UserAgent.

       It is more correct and more complete than HTTP::Lite.  It supports proxies (currently only
       non-authenticating ones) and redirection.  It also correctly resumes after EINTR.

METHODS

new
$http = HTTP::Tiny->new( %attributes );

This constructor returns a new HTTP::Tiny object. Valid attributes include:

• "agent"

A user-agent string (defaults to 'HTTP-Tiny/$VERSION'). If "agent" ends in a space
character, the default user-agent string is appended.

• "cookie_jar"

An instance of HTTP::CookieJar or equivalent class that supports the "add" and
"cookie_header" methods

• "default_headers"

A hashref of default headers to apply to requests

• "local_address"

The local IP address to bind to

• "max_redirect"

Maximum number of redirects allowed (defaults to 5)

• "max_size"

Maximum response size (only when not using a data callback). If defined, responses
larger than this will return an exception.

• "proxy"

URL of a proxy server to use (default is $ENV{http_proxy} if set)

• "no_proxy"

List of domain suffixes that should not be proxied. Must be a comma-separated string
or an array reference. (default is $ENV{no_proxy})

• "timeout"

Request timeout in seconds (default is 60)

• "verify_SSL"

A boolean that indicates whether to validate the SSL certificate of an "https"
connection (default is false)

• "SSL_options"

A hashref of "SSL_*" options to pass through to IO::Socket::SSL

Exceptions from "max_size", "timeout" or other errors will result in a pseudo-HTTP status
code of 599 and a reason of "Internal Exception". The content field in the response will
contain the text of the exception.

See "SSL SUPPORT" for more on the "verify_SSL" and "SSL_options" attributes.

get|head|put|post|delete
$response = $http->get($url);
$response = $http->get($url, \%options);
$response = $http->head($url);

These methods are shorthand for calling "request()" for the given method. The URL must
have unsafe characters escaped and international domain names encoded. See "request()"
for valid options and a description of the response.

The "success" field of the response will be true if the status code is 2XX.

post_form
$response = $http->post_form($url, $form_data);
$response = $http->post_form($url, $form_data, \%options);

This method executes a "POST" request and sends the key/value pairs from a form data hash
or array reference to the given URL with a "content-type" of
"application/x-www-form-urlencoded". If data is provided as an array reference, the order
is preserved; if provided as a hash reference, the terms are sorted on key and value for
consistency. See documentation for the "www_form_urlencode" method for details on the
encoding.

The URL must have unsafe characters escaped and international domain names encoded. See
"request()" for valid options and a description of the response. Any "content-type"
header or content in the options hashref will be ignored.

The "success" field of the response will be true if the status code is 2XX.

mirror
$response = $http->mirror($url, $file, \%options)
if ( $response->{success} ) {
print "$file is up to date\n";
}

Executes a "GET" request for the URL and saves the response body to the file name
provided. The URL must have unsafe characters escaped and international domain names
encoded. If the file already exists, the request will include an "If-Modified-Since"
header with the modification timestamp of the file. You may specify a different
"If-Modified-Since" header yourself in the "$options->{headers}" hash.

The "success" field of the response will be true if the status code is 2XX or if the
status code is 304 (unmodified).

If the file was modified and the server response includes a properly formatted
"Last-Modified" header, the file modification time will be updated accordingly.

request
$response = $http->request($method, $url);
$response = $http->request($method, $url, \%options);

Executes an HTTP request of the given method type ('GET', 'HEAD', 'POST', 'PUT', etc.) on
the given URL. The URL must have unsafe characters escaped and international domain names
encoded.

If the URL includes a "user:password" stanza, they will be used for Basic-style
authorization headers. (Authorization headers will not be included in a redirected
request.) For example:

$http->request('GET', 'http://Aladdin:open sesame@example.com/');

If the "user:password" stanza contains reserved characters, they must be percent-escaped:

$http->request('GET', 'http://john%40example.com:password@example.com/');

A hashref of options may be appended to modify the request.

Valid options are:

• "headers"

A hashref containing headers to include with the request. If the value for a header
is an array reference, the header will be output multiple times with each value in the
array. These headers over-write any default headers.

• "content"

A scalar to include as the body of the request OR a code reference that will be called
iteratively to produce the body of the request

• "trailer_callback"

A code reference that will be called if it exists to provide a hashref of trailing
headers (only used with chunked transfer-encoding)

• "data_callback"

A code reference that will be called for each chunks of the response body received.

If the "content" option is a code reference, it will be called iteratively to provide the
content body of the request. It should return the empty string or undef when the iterator
is exhausted.

If the "content" option is the empty string, no "content-type" or "content-length" headers
will be generated.

If the "data_callback" option is provided, it will be called iteratively until the entire
response body is received. The first argument will be a string containing a chunk of the
response body, the second argument will be the in-progress response hash reference, as
described below. (This allows customizing the action of the callback based on the
"status" or "headers" received prior to the content body.)

The "request" method returns a hashref containing the response. The hashref will have the
following keys:

• "success"

Boolean indicating whether the operation returned a 2XX status code

• "url"

URL that provided the response. This is the URL of the request unless there were
redirections, in which case it is the last URL queried in a redirection chain

• "status"

The HTTP status code of the response

• "reason"

The response phrase returned by the server

• "content"

The body of the response. If the response does not have any content or if a data
callback is provided to consume the response body, this will be the empty string

• "headers"

A hashref of header fields. All header field names will be normalized to be lower
case. If a header is repeated, the value will be an arrayref; it will otherwise be a
scalar string containing the value

On an exception during the execution of the request, the "status" field will contain 599,
and the "content" field will contain the text of the exception.

www_form_urlencode
$params = $http->www_form_urlencode( $data );
$response = $http->get("http://example.com/query?$params");

This method converts the key/value pairs from a data hash or array reference into a
"x-www-form-urlencoded" string. The keys and values from the data reference will be UTF-8
encoded and escaped per RFC 3986. If a value is an array reference, the key will be
repeated with each of the values of the array reference. If data is provided as a hash
reference, the key/value pairs in the resulting string will be sorted by key and value for
consistent ordering.

To preserve the order (r

SSL SUPPORT

Direct "https" connections are supported only if IO::Socket::SSL 1.56 or greater and
Net::SSLeay 1.49 or greater are installed. An exception will be thrown if a new enough
versions of these modules not installed or if the SSL encryption fails. There is no
support for "https" connections via proxy (i.e. RFC 2817).

SSL provides two distinct capabilities:

• Encrypted communication channel

• Verification of server identity

By default, HTTP::Tiny does not verify server identity.

Server identity verification is controversial and potentially tricky because it depends on
a (usually paid) third-party Certificate Authority (CA) trust model to validate a
certificate as legitimate. This discriminates against servers with self-signed
certificates or certificates signed by free, community-driven CA's such as CAcert.org
<http://cacert.org>.

By default, HTTP::Tiny does not make any assumptions about your trust model, threat level
or risk tolerance. It just aims to give you an encrypted channel when you need one.

Setting the "verify_SSL" attribute to a true value will make HTTP::Tiny verify that an SSL
connection has a valid SSL certificate corresponding to the host name of the connection
and that the SSL certificate has been verified by a CA. Assuming you trust the CA, this
will protect against a man-in-the-middle attack <http://en.wikipedia.org/wiki/Man-in-the-
middle_attack>. If you are concerned about security, you should enable this option.

Certificate verification requires a file containing trusted CA certificates. If the
Mozilla::CA module is installed, HTTP::Tiny will use the CA file included with it as a
source of trusted CA's. (This means you trust Mozilla, the author of Mozilla::CA, the
CPAN mirror where you got Mozilla::CA, the toolchain used to install it, and your
operating system security, right?)

If that module is not available, then HTTP::Tiny will search several system-specific
default locations for a CA certificate file:

• /etc/ssl/certs/ca-certificates.crt

• /etc/pki/tls/certs/ca-bundle.crt

• /etc/ssl/ca-bundle.pem

An exception will be raised if "verify_SSL" is true and no CA certificate file is
available.

If you desire complete control over SSL connections, the "SSL_options" attribute lets you
provide a hash reference that will be passed through to "IO::Socket::SSL::start_SSL()",
overriding any options set by HTTP::Tiny. For example, to provide your own trusted CA
file:

SSL_options => {
SSL_ca_file => $file_path,
}

The "SSL_options" attribute could also be used for such things as providing a client
certificate for authentication to a server or controlling the choice of cipher used for
the SSL connection. See IO::Socket::SSL documentation for details.

LIMITATIONS

HTTP::Tiny is conditionally compliant with the HTTP/1.1 specification
<http://www.w3.org/Protocols/rfc2616/rfc2616.html>. It attempts to meet all "MUST"
requirements of the specification, but does not implement all "SHOULD" requirements.

Some particular limitations of note include:

• HTTP::Tiny focuses on correct transport. Users are responsible for ensuring that
user-defined headers and content are compliant with the HTTP/1.1 specification.

• Users must ensure that URLs are properly escaped for unsafe characters and that
international domain names are properly encoded to ASCII. See URI::Escape,
URI::_punycode and Net::IDN::Encode.

• Redirection is very strict against the specification. Redirection is only automatic
for response codes 301, 302 and 307 if the request method is 'GET' or 'HEAD'.
Response code 303 is always converted into a 'GET' redirection, as mandated by the
specification. There is no automatic support for status 305 ("Use proxy")
redirections.

• Persistent connections are not supported. The "Connection" header will always be set
to "close".

• Cookie support requires HTTP::CookieJar or an equivalent class.

• Only the "http_proxy" environment variable is supported in the format
"http://HOST:PORT/". If a "proxy" argument is passed to "new" (including undef), then
the "http_proxy" environment variable is ignored.

• "no_proxy" environment variable is supported in the format comma-separated list of
domain extensions proxy should not be used for. If a "no_proxy" argument is passed to
"new", then the "no_proxy" environment variable is ignored.

• There is no provision for delaying a request body using an "Expect" header.
Unexpected "1XX" responses are silently ignored as per the specification.

• Only 'chunked' "Transfer-Encoding" is supported.

• There is no support for a Request-URI of '*' for the 'OPTIONS' request.

• There is no support for IPv6 of any kind.

Despite the limitations listed above, HTTP::Tiny is considered nearly feature-complete.
If there are enhancements unrelated to the underlying transport, please consider them for
HTTP::Tiny::UA instead.

SUPPORT

   Bugs / Feature Requests
       Please report any bugs or feature requests through the issue tracker at
       <https://github.com/chansen/p5-http-tiny/issues>.  You will be notified automatically of
       any progress on your issue.

   Source Code
       This is open source software.  The code repository is available for public review and
       contribution under the terms of the license.

       <https://github.com/chansen/p5-http-tiny>

         git clone https://github.com/chansen/p5-http-tiny.git

AUTHORS

       •   Christian Hansen <chansen@cpan.org>

       •   David Golden <dagolden@cpan.org>

CONTRIBUTORS

       •   Alan Gardner <gardner@pythian.com>

       •   Alessandro Ghedini <al3xbio@gmail.com>

       •   Brad Gilbert <bgills@cpan.org>

       •   Chris Nehren <apeiron@cpan.org>

       •   Chris Weyl <cweyl@alumni.drew.edu>

       •   Claes Jakobsson <claes@surfar.nu>

       •   Craig Berry <cberry@cpan.org>

       •   David Mitchell <davem@iabyn.com>

       •   Edward Zborowski <ed@rubensteintech.com>

       •   Jess Robinson <castaway@desert-island.me.uk>

       •   Lukas Eklund <leklund@gmail.com>

       •   Martin-Louis Bright <mlbright@gmail.com>

       •   Mike Doherty <doherty@cpan.org>

       •   Petr PisaX <ppisar@redhat.com>

       •   Serguei Trouchelle <stro@cpan.org>

       •   Syohei YOSHIDA <syohex@gmail.com>

       •   Tony Cook <tony@develop-help.com>

COPYRIGHT AND LICENSE

       This software is copyright (c) 2013 by Christian Hansen.

       This is free software; you can redistribute it and/or modify it under the same terms as
       the Perl 5 programming language system itself.