Node.js Open Source application Framework Hapijs Introduction _node.js

First, Hapijs Introduction

Hapijs is an open source, node.js application framework for building applications and services that is designed to allow developers to focus on developing business logic for reusable applications, providing developers with the infrastructure needed to build application business logic. The latest version of Hapijs is the 7.2.0 edition.

Second, Hapijs installation and project configuration

1. Install Hapi Library
the installation of Hapijs is simple, and the following command is executed:

Copy Code code as follows:

$ sudo npm install hapi-g
Hapi@7.2.0/usr/local/lib/node_modules/hapi
├──cryptiles@2.0.4
├──heavy@1.0.0
├──topo@1.0.2
├──accept@1.0.0
├──items@1.1.0
├──kilt@1.1.1
├──catbox-memory@1.1.0
├──boom@2.5.1
├──qs@2.2.4
├──call@1.0.0
├──statehood@1.2.0
├──h2o2@2.0.1
├──iron@2.1.2
├──shot@1.3.5
├──glue@1.0.0
├──wreck@5.0.1
├──hoek@2.8.0
├──catbox@4.0.3
├──vision@1.1.0
├──mimos@1.0.0 (mime-db@1.1.1)
├──rejoice@1.0.0 (bossy@1.0.2)
├──inert@1.1.0 (lru-cache@2.5.0)
├──joi@4.7.0 (isemail@1.1.1)
└──subtext@1.0.1 (content@1.0.1, pez@1.0.0)

2, configure the project

1 Create a new directory named MyProject

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$ mkdir MyProject
$ CD MyProject

2 run the initialization command in the directory

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$ NPM Init

This command generates the Package.json file, which is the metadata for the project.


Then execute the command:

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$ NPM Install--save Hapi

It installs the HAPI library under the project and writes the Hapi dependencies to Package.json.

At this point, everything you need to develop the project is ready.

Iii. Examples of development

1. Create Server

Copy Code code as follows:

Server.js
var Hapi = require (' Hapi ');
var server = new Hapi.server (3000);

Server.start (function () {
Console.log (' Server running at: ', Server.info.uri);
});

First, we need to hapi the library.


Second, we create a new Hapi server object and pass the port number we want to listen to the server object.


Finally, the server object is started and the log information is output.


To illustrate, when we create a server object, we can provide a host name, an IP address, even a UNIX socket file, or a Windows system bound to a server-named pipe.

2, start the server
To execute a command:

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$ node Server.js

To access Http://127.0.0.1:3000/, the browser displays the following:

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{"StatusCode": 404, "Error": "Not Found"}

Very normal, because there is no content on the server itself, the following route logic is added.

3. Routing logic

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Server.js
var Hapi = require (' Hapi ');
var server = new Hapi.server (3000);

Server.route ({
Method: ' Get ',
Path: '/',
Handler:function (Request, Reply) {
Reply (' Hello, world! ');
}
});

Server.route ({
Method: ' Get ',
Path: '/{name} ',
Handler:function (Request, Reply) {
Reply (' Hello, ' + encodeuricomponent (request.params.name) + "!");
}
});

Server.start (function () {
Console.log (' Server running at: ', Server.info.uri);
});

Start the server again:

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$ node Server.js

and access to Http://127.0.0.1:3000/, the browser displays the following:


Hello, world!.


To access Http://127.0.0.1:3000/John, the browser displays the following:


Hello,%e5%bc%a0%e4%b8%89!.

Visible, the routing logic is working properly.

To note:
The parameter of method can be any valid HTTP methods, or it can be an asterisk * (representing any HTTP method).
The path parameter defines an access path that can contain parameters, optional parameters, or even wildcard characters.

Iv. Use of Plug-ins

When creating a Web application, we usually need to access the log. To add basic log output to the application, we can load good plug-ins on the server.

1. Install Good plugin

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$ sudo npm install--save good
good@3.1.1 Node_modules/good
├──json-stringify-safe@5.0.0
├──good-reporter@2.0.0
├──async@0.9.0
├──hoek@2.8.1
├──moment@2.8.3
├──good-file@2.0.0 (items@1.1.0)
└──joi@4.7.0 (topo@1.0.2, isemail@1.1.1)

2, update the Server.js code

Copy Code code as follows:

Server.js
var Hapi = require (' Hapi ');
var good = require (' good ');

var server = new Hapi.server (3000);

Server.route ({
Method: ' Get ',
Path: '/',
Handler:function (Request, Reply) {
Reply (' Hello, world! ');
}
});

Server.route ({
Method: ' Get ',
Path: '/{name} ',
Handler:function (Request, Reply) {
Reply (' Hello, ' + encodeuricomponent (request.params.name) + "!");
}
});

Server.pack.register (Good, function (err) {
if (err) {
Something bad happened loading the plugin
throw err;
}
Server.start (function () {
Server.log (' info ', ' Server running at: ' + Server.info.uri);
});
});

Run Server.js, console output:

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141102/161007.644, info, Server running at:http://localhost:3000

If we proceed to visit: Http://127.0.0.1:3000/liqiang


and Http://127.0.0.1:3000/


The console will continue to output:

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141102/161150.689, request, Http://Thinker-LQ:3000:get/liqiang {} (37MS)
141102/161155.812, request, Http://Thinker-LQ:3000:get/{} (4MS)