Integrating with Web

Create API for stores, store items

From here we jump into a serious design, where our stores will get converted to a server providing service for creating and storing items. Following are the service requests that one can think of:

Create a store
Create an item
Create a category of items
Receive item in store
Issue item from store
Move item from one location to other in a store
Update item
Delete item
Get list of items in master data
Get list of items in stores with balances
Get list of items issued on a day
User authentication
- login
- change password
- forget password
- create user
- assign role
- delete user
- disable user
Create an indent
Create purchase order

and so many more. We will create all of them over time and keep it explained here. Your contributions will be highly appreciated.

Lets take a break from ant and adopt maven. It is far easier and our work load is just going to increase.

Create new project with Maven

Refer to this article, from where this implementation is inspired/guided.

$ mkdir StoresWithMaven
$ cd StoresWithMaven
$ mkdir -p src/main/java/com/dakinegroup/storesApp
$ tree
|-- pom.xml
|-- src
|   `-- main
|       |-- java
|       |   `-- com
|       |       `-- dakinegroup
|       |           `-- storesApp
|       |               |-- StoreController.java
|       |               |-- StoreItem.java
|       |               |-- Store.java
|       |               `-- StoresApp.java
|       `-- resources
|           `-- log4j2.xml
`-- target

Create pom.xml - webservice

Notice following things here:

addition of log4j2 dependencies. They are adopted from log4j2 site.
addition of commons-logging dependencies. They were requried by spring framework. Likely that this will get resolved automatically through spring framework dependency.
name of the artifactid is same as the name of the app file that will be generated
groupId maps to the scoping of our work to particular unique group

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.dakinegroup.storesApp</groupId>
    <artifactId>stores-app</artifactId>
    <version>0.1.0</version>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.2.5.RELEASE</version>
    </parent>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>commons-logging</groupId>
            <artifactId>commons-logging</artifactId>
            <version>1.1.1</version>
        </dependency>
        <dependency>
            <groupId>org.apache.logging.log4j</groupId>
            <artifactId>log4j-api</artifactId>
            <version>2.3</version>
        </dependency>
        <dependency>
            <groupId>org.apache.logging.log4j</groupId>
            <artifactId>log4j-core</artifactId>
            <version>2.3</version>
        </dependency>
    </dependencies>

    <properties>
           <java.version>1.8</java.version>
    </properties>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

    <repositories>
        <repository>
            <id>spring-releases</id>
            <url>https://repo.spring.io/libs-release</url>
        </repository>
    </repositories>
    <pluginRepositories>
        <pluginRepository>
            <id>spring-releases</id>
            <url>https://repo.spring.io/libs-release</url>
        </pluginRepository>
    </pluginRepositories>
</project>

Modifications to Store.java, StoreItem.java

Edit StoresApp.java as

package com.dakinegroup.storesApp;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class StoresApp {

    public static void main(String[] args) {
        SpringApplication.run(StoresApp.class, args);
    }
}

Copy Store.java and StoreItem.java from previous project to src/main/java/com/dakinegroup/storesApp/

Changes to Store.java

Since here we are starting with Store as first, as this class was ignored, lets make some fixes here for

null pointer exception
enabling log4j2 logging
renaming package to com.dakinegroup.storesApp

package com.dakinegroup.storesApp;
...
import org.apache.logging.log4j.Logger;
import org.apache.logging.log4j.LogManager;
...
private static final Logger logger = LogManager.getLogger(StoreItem.class);
...
public void displayInfo() {
    logger.trace("Store Id: "+this.storeId);
    if(items != null) {
    Iterator<StoreItem> it = items.iterator();
    while(it.hasNext()) {

Changes to StoreItem.java

Make following changes to StoreItem.java

renaming package to com.dakinegroup.storesApp

Copy log4j2.xml

Copy this file to src/main/resources directory. This works out to be same as src/ in our earlier sesson.

Run

Now run maven to build project

$ mvn package
$ java -jar target/stores-app-0.1.0.jar

Open code at browser: http://localhost:8080/create?id=test

screendump001

On the terminal, you will see log4j trace coming as..

[localhost].[/]       : Initializing Spring FrameworkServlet 'dispatcherServlet'
2015-08-04 20:21:06.845  INFO 27545 --- [nio-8080-exec-1] o.s.web.servlet.DispatcherServlet        : FrameworkServlet 'dispatcherServlet': initialization started
2015-08-04 20:21:06.877  INFO 27545 --- [nio-8080-exec-1] o.s.web.servlet.DispatcherServlet        : FrameworkServlet 'dispatcherServlet': initialization completed in 32 ms
20:21:07.636 [http-nio-8080-exec-1] TRACE com.dakinegroup.storesApp.StoreItem - Store Id: test

Source code till this point can be downloaded from here

Adding Front End (AngularJs)

Run

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