NAME

    Async::Microservice - Async HTTP Microservice Moose Role

SYNOPSYS

        # lib/Async/Microservice/HelloWorld.pm
        package Async::Microservice::HelloWorld;
        use Moose;
        with qw(Async::Microservice);
        sub service_name {return 'asmi-helloworld';}
        sub get_routes {return ('hello' => {defaults => {GET => 'GET_hello'}});}
        sub GET_hello {
            my ( $self, $this_req ) = @_;
            return [ 200, [], 'Hello world!' ];
        }
        1;
    
        # bin/async-microservice-helloworld.psgi
        use Async::Microservice::HelloWorld;
        my $mise = Async::Microservice::HelloWorld->new();
        return sub { $mise->plack_handler(@_) };
    
        $ plackup -Ilib --port 8089 --server Twiggy bin/async-microservice-helloworld.psgi
    
        $ curl http://localhost:8089/v1/hello
        Hello world!

DESCRIPTION

    This Moose::Role helps to quicly bootstrap async http service that is
    including OpenAPI documentation.

    See https://time.meon.eu/ and Async::Microservice::Time code.

 To bootstrap new async service

    Create new package for your APIs from current examples
    lib/Async/Microservice/*. Inside set return value of service_name. This
    string will be used to set process name and to read/locate OpenAPI yaml
    definition for the documentation. Any GET/POST processing funtions must
    be defined in get_routes funtion.

    Copy one of the bin/*.psgi update it with your new package name.

    Copy one of the root/static/*.yaml to have the same name as
    service_name.

    Now you are able to lauch the http service with:

        plackup -Ilib --port 8089 --server Twiggy bin/async-microservice-YOUNAME.psgi

    In your broser you can read the OpenAPI documentation:
    http://0.0.0.0:8089/v1/ and also use editor to extend it:
    http://0.0.0.0:8089/v1/edit

SEE ALSO

    OpenAPI Specification:
    https://github.com/OAI/OpenAPI-Specification/tree/master/versions or
    https://swagger.io/docs/specification/about/

    Async::MicroserviceReq Twiggy

TODO

        - graceful termination (finish all requests before terminating on sigterm/hup)
        - systemd service file examples
        - static/index.html and static/edit.html are not really static, should be moved

CONTRIBUTORS & CREDITS

    The following people have contributed to this distribution by
    committing their code, sending patches, reporting bugs, asking
    questions, suggesting useful advice, nitpicking, chatting on IRC or
    commenting on my blog (in no particular order):

        you?

    Also thanks to my current day-job-employer https://www.apa-it.at/.

BUGS

    Please report any bugs or feature requests via
    https://github.com/jozef/Async-Microservice/issues.

AUTHOR

    Jozef Kutej

COPYRIGHT & LICENSE

    Copyright 2020 Jozef Kutej, all rights reserved.

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


----------------------------------------------------------------------------
NAME

    Async::MicroserviceReq - async microservice request class

SYNOPSYS

        my $this_req  = Async::MicroserviceReq->new(
            method     => $plack_req->method,
            headers    => $plack_req->headers,
            content    => $plack_req->content,
            path       => $plack_req->path_info,
            params     => $plack_req->parameters,
            static_dir => $self->static_dir,
        );
    
        ...
    
        my $plack_handler_sub = sub {
            my ($plack_respond) = @_;
            $this_req->plack_respond($plack_respond);
        ...

DESCRIPTION

    This is an object created for each request handled by
    Async::Microservice. It is passed to all request handling functions as
    first argument and it provides some request info and response helper
    methods.

ATTRIBUTES

        method
        headers
        path
        params
        plack_respond
        static_dir
        base_url
        want_json
        content
        json_content

METHODS

 text_plain(@text_lines)

    Send text plain response.

 respond($status, $headers, $payload)

    Send plack response.

 redirect($location_path)

    Send redirect.

 static($file_name, $content_cb)

    Send static file, can be updated/modified using optional callback.

 get_pending_req

    Returns number of currently pending async requests.


----------------------------------------------------------------------------
NAME

    Async::Microservice::Time - example time async microservice

SYNOPSYS

        # can be started using:
        plackup --port 8085 -Ilib --access-log /dev/null --server Twiggy bin/async-microservice-time.psgi
    
        curl "http://localhost:8085/v1/hcheck" -H "accept: application/json"
        curl "http://localhost:8085/v1/epoch"  -H "accept: application/json"
        curl "http://localhost:8085/v1/datetime?time_zone=local" -H "accept: application/json"

DESCRIPTION

    This is an example asynchronous http micro service using
    Async::Microservice. View the source code it's minimal.

METHODS

 service_name

    Just a name, used to identify process and look for OpenAPI
    documentation.

 get_routes

    Path::Router configuration for dispatching

 http response methods

  GET_datetime

    https://time.meon.eu/v1/datetime

  POST_datetime

        $ curl -X POST "https://time.meon.eu/v1/datetime" -H  "accept: application/json" -H  "Content-Type: application/json" -d "{\"epoch\":-42}"
        {
           "date" : "1969-12-31",
           "datetime" : "1969-12-31 23:59:18 +0000",
           "day" : "31",
           "epoch" : -42,
           "hour" : "23",
           "minute" : "59",
           "month" : "12",
           "second" : "18",
           "time" : "23:59:18",
           "time_zone" : "+0000",
           "time_zone_name" : "UTC",
           "year" : "1969"
        }

  GET_epoch

    https://time.meon.eu/v1/epoch

  GET_sleep

    https://time.meon.eu/v1/sleep?duration=2.5

    This is the only parallel processed reponse method (the other ones are
    pure CPU-only bound) that sleep given (or random) number of seconds and
    only then returns the request response with when it started and how
    long it took. Normally this the same as what is in duration parameter,
    but in case the server is overloaded with requests, the event loop may
    call the timer handler much later than the duration. Try:

        ab -n 1000 -c 500 http://localhost:8085/v1/sleep?duration=3
        Connection Times (ms)
                      min  mean[+/-sd] median   max
        Connect:        0  259 432.8     21    1033
        Processing:  3001 3090  72.5   3061    3253
        Waiting:     3001 3090  72.5   3061    3253
        Total:       3022 3349 394.1   3155    4065

    Then try to run together with 100% CPU load:

        ab -q -n 10000 -c 50 http://localhost:8085/v1/datetime

  the rest

    Check out Async::Microservice for built-in http response methods.

SEE ALSO

    t/02_Async-Microservice-Time.t for an example how to test this service.