{"id":12983,"date":"2021-01-08T17:24:59","date_gmt":"2021-01-08T16:24:59","guid":{"rendered":"https:\/\/www.codemotion.com\/magazine\/?p=12983"},"modified":"2022-01-05T20:03:24","modified_gmt":"2022-01-05T19:03:24","slug":"faas-wars-serverless-robot","status":"publish","type":"post","link":"https:\/\/www.codemotion.com\/magazine\/backend\/faas-wars-serverless-robot\/","title":{"rendered":"Are You Ready for the FaaS Wars?"},"content":{"rendered":"\t\t\t\t
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\n\t\t\t\t\t\t\tTable Of Contents\t\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t
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  1. Robots and Serverless APIs<\/a>
  2. Meet your Serverless Robot<\/a>
  3. Taking Command of Your FaaSfighter<\/a>
  4. Getting your Serverless Robot moving<\/a>
  5. Events and Reactions<\/a>
  6. Improve your Fighter<\/a>
  7. Make your Serverless Robot Stateful<\/a>
  8. Making use of saved History<\/a>
  9. A few final refinements for our Serverless Robot<\/a>
  10. In Conclusion…<\/a><\/ol>\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\r\n\r\n\r\n

    Organised by Nimbella and promoted by several members of the Apache OpenWhisk community, FaaS Wars<\/a> is a programming competition that allows participants to learn how to use ‘serverless’ in a fun way. Competitors strive against each other for cash prizes for creating the best serverless<\/a> virtual robot.<\/p>\r\n\r\n\r\n\r\n

    The basic concept of the competition is simple: participants write code<\/span> to manoeuvre a FaaSfighter<\/strong> robot across a field of combat, firing lasers at another competitor\u2019s robot. To win, a robot must hit the enemy robot five times in a minute-long \u2018battle\u2019, and also avoid being hit by its opponent\u2019s lasers.<\/p>\r\n\r\n\r\n\r\n

    Robots and Serverless APIs<\/h2>\r\n\r\n\r\n\r\n

    Before you can begin your campaign, you need to first use Nimbella<\/a> to build a serverless API<\/span><\/strong> with which to control your robot\u2019s movements. An event describing the state of the game is received by the API, which responds by giving the FaaSfighter robot orders. The tutorial below explains how to build your fighter and offers battle strategies that gradually increase in \u2018smartness\u2019.<\/p>\r\n\r\n\r\n\r\n

    JavaScript<\/a> is used to implement the API in the examples that follow. However, any other language that is compatible with Nimbella can be used, such as Python<\/a> and Go<\/a>.<\/p>\r\n\r\n\r\n\r\n

    A \u2018Nimbella action\u2019 is the name given to an API<\/a> that is implemented on a serverless basis. A JSON<\/span> object that encodes the state of the game (“the event”) is sent as input to the action. The output returned – the \u2018orders\u2019 – is in JSON as well. The below examples can easily be translated into your chosen language.<\/p>\r\n\r\n\r\n\r\n

    Meet your Serverless Robot<\/h2>\r\n\r\n\r\n\r\n

    The built-in<\/span> editor in FaaS Wars<\/a> is used to write the code<\/span> that will control your robot. Your code<\/span> operates as a function with this format:<\/p>\r\n\r\n\r\n\r\n

    \r\n
    \"serverless<\/figure>\r\n<\/div>\r\n\r\n\r\n\r\n

    The return needs to be a JSON dictionary with the property body<\/code> that contains an array of orders destined for your fighter (more details follow). At this stage, the robot is not yet mobile but sits still, vulnerable to the lurking opposition.<\/p>\r\n\r\n\r\n\r\n

    Taking Command of Your FaaSfighter<\/h2>\r\n\r\n\r\n\r\n

    The following function<\/span> sends the robot a single order at each point in the game, producing an array that incorporates the instruction\u00a0 to “yell” the relevant instruction or information while in battle. This particular example communicates the time at which the order is given.<\/p>\r\n\r\n\r\n\r\n

    \r\n
    \"serverless<\/figure>\r\n<\/div>\r\n\r\n\r\n\r\n

    Adopting this action as your first battle strategy will result in your robot being a great timekeeper until a robot with more useful skills destroys it, or the battle time runs out. It\u2019s always great to know what time it is, but it\u2019s not the most effective of battle strategies.\u00a0 Nonetheless, your robot is now active, even if all it can do is tell the time!<\/p>\r\n\r\n\r\n\r\n

    Getting your Serverless Robot moving<\/h2>\r\n\r\n\r\n\r\n

    The next step is to get your robot moving on the battlefield. As discussed above, an array of commands is returned by the action, so a single function execution allows you to give several orders. \u200b This action tells the robot to move forward before turning to the left:<\/p>\r\n\r\n\r\n\r\n

    \r\n
    \"serverless<\/figure>\r\n<\/div>\r\n\r\n\r\n\r\n

    Running this code results in the robot moving around in a square as it repeatedly follows the instruction to move forward 50 pixels<\/span> before turning 90 degrees to the left. If another player hits the robot, it may be forced off course and take a new, random orientation.<\/p>\r\n\r\n\r\n\r\n

    Events and Reactions<\/h2>\r\n\r\n\r\n\r\n

    Throughout the game, the robot is continuously receiving information about its environment from the args<\/code> parameter. At the top of your list of things to check should be args.event<\/code><\/p>\r\n\r\n\r\n\r\n

    Your robot can react to four different event types:<\/p>\r\n\r\n\r\n\r\n