NAME
Net::API::REST - Framework for RESTful APIs
SYNOPSIS
package MyPackage;
BEGIN
{
use strict;
use curry;
use parent qw( Net::API::REST );
use Net::API::Stripe;
};
sub init
{
my $self = shift( @_ );
$self->{routes} =
{
# API version 1
1 =>
{
'favicon.ico' => $self->curry::noop,
auth =>
{
google =>
{
_handler => $self->curry::oauth_google,
callback => $self->curry::oauth_google(callback => 1),
},
linkedin =>
{
_handler => $self->curry::oauth_linkedin,
callback => $self->curry::oauth_linkedin(callback => 1),
},
},
},
stripe => $self->curry::stripe,
# Whatever method is fine. Will call the method handle in package MyAPI::Users to handle the endpoint
users => 'MyAPI::Users->handle',
preferences =>
{
_access_control => 'restricted',
_delete => $self->curry::remove_preferences,
_get => $self->curry::get_preferences,
_post => $self->curry::update_preferences,
},
};
$self->{api_version} = 1;
$self->{supported_api_versions} = [qw( 1 )];
# By default, we support the GET and POST to access our endpoints
# It may be adjusted endpoint by endpoint and if nothing is specified this default is used.
$self->{default_methods} = [qw( GET POST )];
# This is ALL possible supported methods
$self->{supported_methods} = [qw( DELETE GET HEAD OPTIONS POST PUT )];
$self->{supported_languages} = [qw( en-GB en fr-FR fr ja-JP )];
$self->{key} = 'kAncmaDajnacSnbGmbXamn';
# We want JWE (Json Web Token encrypted). This will affect jwt_encode's behaviour
$self->{jwt_encrypt} = 1;
# Because we are encrypting
$self->{jwt_algo} = 'PBES2-HS256+A128KW';
$self->{jwt_encoding} = 'A128GCM' unless( length( $self->{jwt_encoding} ) );
$self->{jwt_accepted_algo} = [qw( PBES2-HS256+A128KW HS256 )];
$self->{jwt_accepted_encoding} = [qw( A128GCM )];
$self->SUPER::init( @_ );
return( $self );
}
sub stripe
{
my $self = shift( @_ );
my $ep = $self->endpoint;
my $pinfo = $ep->path_info;
my $remote_ip = $self->request->remote_ip;
my $sig = $self->request->headers( 'Stripe-Signature' );
return( $self->reply({ code => Apache2::Const::HTTP_BAD_REQUEST, message => "No signature found" }) ) if( !CORE::length( $sig ) );
my $payload = $self->request->data || return( $self->reply({ code => Apache2::Const::HTTP_BAD_REQUEST, message => "No payload data received from the client." }) );
## Net::API::Stripe object
my $stripe = Net::API::Stripe->new(
# Enable debug to get debug data in http server log
debug => 0,
conf_file => "/home/john_doe/stripe-settings.json",
) || do
{
$self->message( 3, "Unable to initiate a Net::API::Stripe object using the configuration file /home/john_doe/stripe-settings.json" );
return( $self->reply({ code => Apache2::Const::HTTP_INTERNAL_SERVER_ERROR, message => $self->oops }) );
};
# Do an IP source check to be sure this is Stripe talking to us
if( !defined( my $ip_check = $stripe->webhook_validate_caller_ip({ ip => $remote_ip, ignore_ip => $ignore_ip }) ) )
{
return( $self->reply({ code => $stripe->error->code, message => $stripe->error->message }) );
}
# Now, we make sure this is Stripe sending this by checking the signature of the payload
my $check = $stripe->webhook_validate_signature({
secret => $signing_secret,
signature => $sig,
payload => $payload,
time_tolerance => $max_time_spread,
});
if( !defined( $check ) )
{
return( $self->reply({code => $stripe->error->code, message => $stripe->error->message }) );
}
# Ok, if we are here, we passed all checks
# Don't wait, reply ok back to Stripe so our request does not time out
$self->response->code( Apache2::Const::HTTP_OK );
my $json = $self->json->utf8->encode({ code => 200, success => $self->true });
$self->response->print( $json );
$self->response->rflush;
# Do something with the payload received
my $evt = $stripe->event( $payload ) ||
return( $self->reply({ code => Apache2::Const::HTTP_INTERNAL_SERVER_ERROR, message => $self->oops }) );
printf( STDERR "Received an event from api version %s on %s for Stripe object type %s\n", $evt->api_version, $evt->created->iso8601, $evt->type );
return( Apache2::Const::HTTP_OK );
}
VERSION
v1.0.0
DESCRIPTION
The purpose of this module is to provide a powerful, yet simple framework to implement a RESTful API under Apache2 mod_perl.
As of version 1.0.0
, this module inherits from Apache2::API. Please check its documentation. Other methods specific to this module are documented here.
METHODS
new
This initiates the package and take the following parameters:
request
This is a required parameter to be sent with a value set to a Apache2::RequestRec object
debug
Optional. If set with a positive integer, this will activate verbose debugging message
api_uri()
Returns the api URI as a URI
object.
api_version( integer or decimal )
Get or sets the current api version on the server.
base_path( path )
If in the Directory directive of the Apache Virtual Host, a Net_API_REST_Base
was set, this method will be set with this value.
compression_threshold( integer )
The number of bytes threshold beyond which, the reply method will gzip compress the data returned to the client.
default_methods( [ qw( GET POST ... ) ] )
This sets or gets the default methods supported by an endpoint.
endpoint( [ Net::API::REST::Endpoint object ] )
This gets or sets an Net::API::REST::Endpoint object.
handler
This is the main method called by Apache to handle the response. To make this work, in the Apache configuration, you must set the handler to your package and have your package inherit from Net::API::REST. For example:
PerlResponseHandler MyPackage
When called by Apache, handler will initiate a Net::API::REST::Request object and a Net::API::REST::Response
If the incoming request is an OPTIONS request such as a typical one issued during a javascript Ajax call, it will call the method http_options() which will also set the cors policy by calling http_cors()
Finally, it will try to find a route for the endpoint sought in the incoming query, and construct a Net::API::REST::Endpoint object with the context information of the endpoint, including information such as variables that could exist in the path. For example:
/org/jp/llc/123/directors/42/profile
Here the llc property has an id 123 and the directors property has an id 42. Those two variables are stored in the Net::API::REST::Endpoint object. This object can then be accessed with the method endpoint
Having found a route, handler calls the anonymous subroutine in charge of handling the endpoint.
If no route was found, handler returns a 400 Bad Request
.
If the endpoint handler returns undef(), handler will return a 500 Server Error
, otherwise it will pass the return value back to Apache. The return value should be an Apache2::Const return code.
http_cors()
Checks http request context and set the proper CORS http headers.
http_options()
If the request is an OPTIONS request, this method is called. It will do a pre-flight check
and look forward to see if the user has access to the resource sought and sets the response http headers accordingly.
init_headers( code reference )
If this is set, then Net::API::REST::handler will call it.
is_allowed
Get or set handlers to check permission for various aspects of the api.
Each handler must return a valid HTTP Status code as an Apache2::Cons value and if the returned code is an error, Net::API::REST will stop right there and return it to Apache. See Net::API::REST::Status for more information.
Currently supported handlers types are:
- access
-
This is called in "handler" and before it runs the code associated with the endpoint.
For example:
$self->is_allowed( access => sub { my $req = $self->request; my $ep = $self->endpoint; my $ref; # See: <https://cheatsheetseries.owasp.org/cheatsheets/REST_Security_Cheat_Sheet.html> if( $ep->access eq 'restricted' ) { if( !$req->headers->get( 'Authorization' ) || !$req->headers->get( 'X-CSRF-Token' ) ) { return( Apache2::Const::HTTP_NOT_ACCEPTABLE ); } elsif( !( $ref = $self->auth_check ) ) { return( Apache2::Const::HTTP_UNAUTHORIZED ); } } # To implement the double submit security measure elsif( !$req->headers->get( 'X-CSRF-Token' ) ) { return( Apache2::Const::HTTP_NOT_ACCEPTABLE ); } });
- content_type
-
This handler, if present, is called from "handler" before executing the code reference associated with the endpoint.
It is designed to check the content type in the request is acceptable as a security measure recommended and described in OWASP REST security cheat sheet
For example:
$self->is_allowed( content_type => sub { my $type = shift( @_ ); # You can also get the request content type with: # my $type = $self->request->type; });
- method
-
This handler, if present, is called with the request method (e.g. GET, POST, etc) to check if it is allowed.
Note that
OPTIONS
is different and should always be allowed to implement pre-flight check for CORSFor example:
$self->is_allowed( method => sub { my $meth = shift( @_ ); my $ok_methods = [qw( GET POST )]; return( Apache2::Const::HTTP_METHOD_NOT_ALLOWED ) if( !scalar( grep( $meth eq $_, @$ok_methods ) ) ); });
Note that this is equivalent to setting the value of "supported_methods" to an array reference with values
GET POST
, but provides you with more granularity and control. - network
-
This is called very early in "handler" and is designed to check if the user's ip is authorised to access the api.
The handler is called with the remote ip address as a string.
This could be a good opportunity to check for api abuse and throttling.
For example:
$self->is_allowed( network => sub { my $ip = shift( @_ ); if( $self->is_banned( $ip ) ) { return( Apache2::Const::HTTP_FORBIDDEN ); } elsif( $self->is_throttled( $ip ) ) { return( Apache2::Const::HTTP_TOO_MANY_REQUESTS ); } else { # returning Apache2::Const::OK would work too although it is not the same value return( Apache2::Const::HTTP_OK ); } });
jwt_accepted_algo( string )
Get or set the algorithm supported for the JWT tokens.
jwt_accepted_encoding( string )
Get or set the supported encoding for the JWT tokens.
jwt_algo( string )
The chosen algorithm to create JWT tokens
jwt_decode( token )
Given a JWT token, this will decode it and returns a hash reference
jwt_encode
Provided with an hash reference of parameters, and this will prepare the token data and call "encode_jwt" in Net::API::REST::JWT
It accepts the following arguments and additional arguments recognised by Net::API::REST::JWT can also be provided and will be passed to "encode_jwt" in Net::API::REST::JWT directly.
It returns the encrypted token as a string or undef
if an error occurred which can be retrieved using the "error" in Module::Generic method.
algo
This will set the alg property in the token.
audience
This will set the aud property in the token payload.
encoding
This will set the enc property in the token payload.
encrypt
If true, this will encrypt the token. When provided this will affect the algo.
For example, when not encrypted, by default the algorithm used is
HS256
, but when encryption is activated, the algorithm becomesPBES2-HS256+A128KW
expires
This will set the exp property in the token payload.
issued_at
This will set the iat property in the token payload.
issuer
This will set the iss property in the token payload.
key
This will set the key property in the token payload.
payload
The hash data to become the token payload. It can contains discretionary elements.
subject
This will set the sub property in the token payload.
ttl
If provided, this will set the exp property to iat + ttl
jwt_encoding
jwt_encrypt
jwt_extract
jwt_verify
jwt_verify_audience
key
request()
Returns the Net::API::REST::Request object. This object is set early during the instantiation in the handler method.
response
Returns the Net::API::REST::Response object. This object is set early during the instantiation in the handler method.
route( URI object )
Given an uri, this will find the route for the endpoint sought and return and Net::API::REST::Endpoint object. If nothing found, it will return an empty string. If there was an error, it will return undef
and set an error object that can be retrieved with the inherited "error" in Module::Generic method. The error object will also contain a code
attribute which will represent an http status code.
"route" is called from "handler" to get the endpoint object and related handler, then calls the handler after performing a number of operations. See "handler" for more information.
Otherwise, a Net::API::REST::Endpoint is returned.
routes( hash reference )
This sets the routes for all the endpoints proposed by the RESTful server
supported_api_versions( array reference )
Get or set the list of supported api versions
supported_languages( array reference )
Get or set the list of supported language codes, such as fr_FR, en_GB, ja_JP, zh_TW, etc
supported_methods( array reference )
well_known()
If the http request is for /.well-know, then we simply decline to process it.
This does not mean it won't get processed, but just that we pass and let Apache handle it directly.
_try( object type, method name, @_ )
Given an object type, a method name and optional parameters, this attempts to call it.
Apache2 methods are designed to die upon error, whereas our model is based on returning undef
and setting an exception with Module::Generic::Exception, because we believe that only the main program should be in control of the flow and decide whether to interrupt abruptly the execution, not some sub routines.
AUTHOR
Jacques Deguest <jack@deguest.jp>
SEE ALSO
Net::API::REST::JWT, Net::API::REST::Endpoint, Net::API::REST::Request, Net::API::REST::Response
Apache2::API::DateTime, Apache2::API::Query, Apache2::API::Request, Apache2::API::Response, Apache2::API::Status
Apache2::Request, Apache2::RequestRec, Apache2::RequestUtil
COPYRIGHT & LICENSE
Copyright (c) 2018-2023 DEGUEST Pte. Ltd.
You can use, copy, modify and redistribute this package and associated files under the same terms as Perl itself.