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

    v0.8.0

DESCRIPTION

The purpose of this module is to provide a powerful, yet simple framework to implement a RESTful API under Apache2 mod_perl.

METHODS

new( hash )

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

apache_request()

Returns the Apache2::RequestRec object.

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.

bailout( error string )

Given an error message, this will prepare the http header and response accordingly.

It will call gettext to get the localised version of the error message, so this method is expected to be overriden by inheriting package.

If the outgoing content type set is application/json then this will return a properly formatted standard json error, such as:

    { "error": { "code": 401, "message": "Something went wrong" } }

Otherwise, it will send to the client the message as is.

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.

decode_base64( data )

Given some data, this will decode it using base64 algorithm. It uses APR::Base64::decode in the background, because MIME::Decoder may have some issue under mod_perl.

decode_json( data )

This decode from utf8 some data into a perl structure.

If an error occurs, it will return undef and set an exception that can be accessed with the error method.

decode_uri( $string )

Provided with an uri encoded string, and this uses URI::Escape to return its decoded form.

See also "encode_uri"

decode_url( $string )

Given a url-encoded string, this returns the decoded string

This uses APR::Request XS method.

decode_utf8( data )

Decode some data from ut8 into perl internal utf8 representation.

If an error occurs, it will return undef and set an exception that can be accessed with the error method.

default_methods( [ qw( GET POST ... ) ] )

This sets or gets the default methods supported by an endpoint.

encode_base64( data )

Given some data, this will encode it using base64 algorithm. It uses APR::Base64::encode in the background, because MIME::Decoder may have some issue under mod_perl.

encode_json( hash reference )

Given a hash reference, this will encode it into a json data representation.

However, this will not utf8 encode it, because this is done upon printing the data and returning it to the client.

encode_uri( $string )

Provided with a string, and this uses URI::Escape to return an uri encoded string.

See also "decode_uri"

encode_url( $string )

Given a string, this returns its url-encoded version

This uses APR::Request XS method.

encode_utf8( data )

This encode in ut8 the data provided and return it.

If an error occurs, it will return undef and set an exception that can be accessed with the error method.

endpoint( [ Net::API::REST::Endpoint object ] )

This gets or sets an Net::API::REST::Endpoint object.

generate_uuid()

Generates an uuid string and return it.

get_auth_bearer()

Checks whether an Authorization http header was provided, and get the Bearer value.

If no header was found, it returns an empty string.

If an error occurs, it will return undef and set an exception that can be accessed with the error method.

get_handlers()

Returns a reference to a list of handlers enabled for a given phase.

    $handlers_list = $res->get_handlers( $hook_name );

A list of handlers configured to run at the child_exit phase:

    @handlers = @{ $res->get_handlers( 'PerlChildExitHandler' ) || []};

gettext( 'string id' )

Get the localised version of the string passed as an argument.

This is supposed to be superseded by the package inheriting from Net::API::REST

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.

header_datetime( DateTime object )

Given a DateTime object, this sets it to GMT time zone and set the proper formatter (Net::API::REST::DateTime) so that the stringification is compliant with http headers standard.

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 CORS

For 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 );
        }
    });

is_perl_option_enabled()

Checks if perl option is enabled in the Virtual Host and returns a boolean value

json()

Returns a JSON object.

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 becomes PBES2-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

lang( string )

Set or get the current language

lang_unix( string )

Given a language, this returns a language code formatted the unix way, ie en-GB would become en_GB

lang_web( string )

Given a language, this returns a language code formatted the web way, ie en_GB would become en-GB

log_error( string )

Given a string, this will log the data into the error log.

When log_error is accessed with the Apache2::RequestRec the error gets logged into the Virtual Host log, but when log_error gets accessed via the Apache2::ServerUtil object, the error get logged into the Apache main error log.

print( list )

print out the list of strings and returns the number of bytes sent.

push_handlers

reply( http code, message | hash reference )

Given an http code and a message, or just a hash reference, reply will find out if the code provided is an error and format the replied json appropriately like:

    { "error": { "code": 400, "message": "Some error" } }

It will json encode the returned data and print it out back to the client after setting the http returned code.

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

server()

Returns a Apache2::Server object

server_version()

Tries hard to find out the version number of the Apache server.

set_handlers()

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 )

Get or set the list of supported http methods.

warn( list )

Given a list of string, this sends a warning.

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.

Net::API::REST::Endpoint methods

access()

This specifies the level of access: private or restricted

handler()

Returns the handler found to handle the endpoint

is_method_allowed()

Returns a boolean on whether the given method is allowed.

methods()

Returns an array reference of the methods allowed for this endpoint.

path_info()

Returns a string for this path info, if any.

supported_content_types

Sets or gets an array of supported content types

variables()

Returns a hash reference of name => value pairs for the variables found in the endpoint sought by in the http request. For example:

    /org/jp/llc/12/directors/23/profile

In this case, llc has an id value of 12 and the director an id value of 23. They will be recorded as variables as instructed by the route map set by the package using Net::API::REST

AUTHOR

Jacques Deguest <jack@deguest.jp>

CPAN ID: jdeguest

https://gitlab.com/jackdeguest/Net-API-REST

SEE ALSO

Net::API::REST::Cookie, Net::API::REST::DateTime, Net::API::REST::JWT, Net::API::REST::Endpoint, Net::API::REST::Query, Net::API::REST::Request, Net::API::REST::Request::Params, Net::API::REST::Request::Upload, Net::API::REST::Response, Net::API::REST::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.