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    OAuth::Cmdline 0.03
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NAME
    OAuth::Cmdline - OAuth2 for command line applications using web services

SYNOPSIS
          # Use a site-specific class instead of the parent class, see
          # description below for generic cases

        my $oauth = OAuth::Cmdline::GoogleDrive->new( );
        $oauth->access_token();

DESCRIPTION
    OAuth::Cmdline helps standalone command line scripts to deal with web
    services requiring OAuth access tokens.

WARNING: LIMITED ALPHA RELEASE
    While "OAuth::Cmdline" has been envisioned to work with various
    OAuth-controlled web services, it currently only works with the Google
    Drive API and Spotify. But stay tuned, I'll refactor the site-specific
    parts of the code soon, so that it'll work with Evernote, Tumblr and
    others as well. Hey, or send me a pull request if you want to beat me to
    it! :) So far the following subclasses are available:

        OAuth::Cmdline::GoogleDrive
        OAuth::Cmdline::Spotify

    If you want to use this module for a different service, go ahead and try
    it, it might just as well work. In this case, specify the "site"
    parameter, which determines the name of the cache file with the access
    token and other settings in your home directory:

          # Will use standard OAuth techniques and save your
          # tokens in ~/.some-other.site.yml
        my $oauth = OAuth::Cmdline->new( site => "some-other-site" );

GETTING STARTED
    To obtain the initial set of access and refresh tokens from the
    OAuth-controlled site, you need to register your command line app with
    the site and you'll get a "Client ID" and a "Client Secret" in return.
    Also, the site's SDK will point out the "Login URI" and the "Token URI"
    to be used with the particular service. Then, run the following script
    (the example uses the Spotify web service)

        use OAuth::Cmdline;
        use OAuth::Cmdline::Mojo;

        my $oauth = OAuth::Cmdline::GoogleDrive->new(
            client_id     => "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX",
            client_secret => "YYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYY",
            login_uri     => "https://accounts.spotify.com/authorize",
            token_uri     => "https://accounts.spotify.com/api/token",
            scope         => "user-read-private",
        );
    
        my $app = OAuth::Cmdline::Mojo->new(
            oauth => $oauth,
        );
    
        $app->start( 'daemon', '-l', $oauth->local_uri );

    and point a browser to the URL displayed at startup. Clicking on the
    link displayed will take you to the OAuth-controlled site, where you
    need to log in and allow the app access to the user data, following the
    flow provided on the site. The site will then redirect to the web server
    started by the script, which will receive an initial access token with
    an expiration date and a refresh token from the site, and store it
    locally in the cache file in your home directory (~/.sitename.yml).

ACCESS TOKEN ACCESS
    Once the cache file has been initialized, the application can use the
    "access_token()" method in order to get a valid access token. If
    "OAuth::Cmdline" finds out that the cached access token is expired,
    it'll automatically refresh it for you behind the scenes.

    "OAuth::Cmdline" also offers a convenience function for providing a hash
    with authorization headers for use with LWP::UserAgent:

        my $resp = $ua->get( $url, $oauth->authorization_headers );

    This will create an "Authorization" header based on the access token and
    include it in the request to the web service.

  Public Methods
    "new()"
        Instantiate a new OAuth::Cmdline::XXX object. XXX stands for the
        specific site's implementation, and can be "GoogleDrive" or
        "Spotify" or similar.

    "authorization_headers()"
        Returns the HTTP header name and value the specific site requires
        for authentication. For example, in GoogleDrive's case, the values
        are:

            AuthorizationBearer xxxxx.yyy

        The method is used to pass the authentication header key and value
        to an otherwise unauthenticated web request, like

            my $resp = $ua->get( $url, $oauth->authorization_headers );

    "token_expired()"
        (Internal) Check if the access token is expired and will be
        refreshed on the next call of "authorization_headers()".

    "token_expire()"
        Force the expiration of the access token, so that the next request
        obtains a new one.

LEGALESE
    Copyright 2014 by Mike Schilli, all rights reserved. This program is
    free software, you can redistribute it and/or modify it under the same
    terms as Perl itself.

AUTHOR
    2014, Mike Schilli <cpan@perlmeister.com>

