Yesterday, I was attracted by the cool big screen of Alibaba cloud ！

I’ve been waiting 85 There are so few post developers ！ I’m curious what the hell is 90、95 After playing ？ I took a deep look at .

This is one about Serverless Experience activities of ,Serverless In China, it has always been in a state of tepid and tepid , So many developers don’t really understand Serverless In the end is what ！

If you have this curiosity , Then you can experience it just like me , Write a simple Hello World, Have a most intuitive feeling of this product full of future sense ！

P.S. Participate in activities , Join the nail group and draw once a day , Have a chance to win AirPods、 the height is PG Model （ I like ）、Cherry Mechanical keyboard and other rich gifts ！

How to participate

-【 official 】 Activity home page ：https://developer.aliyun.com/topic/yiqi/hol?utm_content=g_1000180354 -【 official 】 Customs clearance book ：https://help.aliyun.com/document_detail/181573.html

Official documents, like other Alibaba projects, need to be improved （lan）….

If you have enough confidence in your own ability to explore , You can try it directly through official documents .

If you want to step on the pit less , You can see what I wrote below Super detailed customs clearance book , To complete a Java Version of Hello World！

First step ： Enter the product list , I’m gonna go ahead and create an app

The second step ： choice “ Empty application ” label

• Serverless Application server selection ：“ Function calculation FC”
• Develop language options ：Java

The third step ： Fill in the application name 、 Application Introduction , Just define yourself

Step four ： Click… In the new application card “ Development and deployment ” Button

Step five ： newly build helloworld.java

The contents are as follows ：

package com.alibaba.serverless.helloworld;
import java.io.UnsupportedEncodingException;
import java.util.UUID;
import com.aliyun.fc.runtime.Context;
import com.aliyun.fc.runtime.FunctionComputeLogger;
import com.aliyun.fc.runtime.FunctionInitializer;
import com.aliyun.fc.runtime.PojoRequestHandler;
import com.aliyuncs.utils.Base64Helper;
/**
* Corresponds to the function name in the deployment route ：
* com.alibaba.serverless.helloworld.helloworld::handleRequest
*/
public class helloworld implements FunctionInitializer, PojoRequestHandler<ApiGwRequest, ApiGwResponse> {
/*
* The callback function when the cloud function is initialized .
*/
@Override
public void initialize(Context context) {
FunctionComputeLogger logger = context.getLogger();
logger.debug(String.format("RequestID is %s %n", context.getRequestId()));
}
/*
* Web Cloud function processing entry , Every time the entry is called .
* @param request All the information requested is in request in
*/
@Override
public ApiGwResponse handleRequest(ApiGwRequest request, Context context) {
FunctionComputeLogger logger = context.getLogger();
// Read request object
String requestPath = request.getPath();
String bodyContext = "";
if (requestPath.startsWith("")) {
bodyContext = " Hello , The world ！";
}
// Building return objects
ApiGwResponse response = new ApiGwResponse();
response.getHeaders().put("responseHeader", "testValue");
response.getHeaders().put("Content-type", "text/html; charset=utf-8");
boolean isBase = false;
if ( isBase ) {
try {
bodyContext = Base64Helper.encode(bodyContext, "UTF-8");
} catch (UnsupportedEncodingException e) {
isBase = false;
}
}
response.setBody( bodyContext );
response.setBase64Encoded( isBase );
response.setStatusCode(200);
logger.info("Response return :" + bodyContext );
return response;
}
}

Step six ： Follow the diagram below , Submission code

Step seven ： Deploy to everyday environments

Click the first icon on the left toolbar , Enter the deployment interface , Click on “ Add a route ”.

In the figure 2 Part of the content is ： com.alibaba.serverless.helloworld.helloworld::handleRequest, The corresponding is created before helloworld.java Medium handleRequest Law , It means /helloworld The request will be sent to the handleRequest To deal with it .

Be careful , The request method should be set to POST, I’ll tell you why ！

Step eight ： test /helloworld Interface

Next to the deployment tab is a test tool , Enter the user path /helloworld, Click test to initiate the request , The results are shown in the figure below ：

Looking back at the code , Right body Content ：

Does this testing tool always feel a little strange ？！ Yes , There is no such thing as HTTP Request Method The choice of , This request is used by default POST It’s coming , So in the last step, we configured /helloworld by POST request , Otherwise it won’t work here . Look at the official book of brothers , Did you find this hole ？

How about ？ Your first time Serverless Did the trip go well ？

Click here to try out this future development approach

First article ：Serverless First experience ： Quickly develop and deploy a Hello World（Java edition ）, Reprint please indicate the source . Welcome to my official account. ： Program the ape DD, Get exclusive learning resources and daily dry goods push .