Employee Management System

This is a set of API's to manage employee system in an organization. At present, system supports below functions:

• Register for API access
• Add an Employee
• Get an Employee
• Update an Employee Data - Full/Partial
• Delete Employee

Technology Stack

• Language
  • Java 1.7
  • Servlet 3.1
• Frameworks
  • MVC - Spring 4
  • ORM - Hibernate & JPA
  • Logging - Log4J
  • Unit Test - JUnit/Mockito
• Database
  • MySQL (InMemory)
• Build Tools
  • Maven 3.2.3

Building

This project use Java and Maven, before proceeding to next step please make sure that you have all required dependencies on your system.

- Verify Java

Open command prompt (Windows) or Terminal (Mac/Linux) and run below command

$ java -version
java version "1.7.51_16"
Java(TM) SE Runtime Environment (build 1.7.51_16-b02)
Java 
HotSpot(TM) 64-Bit Server VM (build 25.74-b02, mixed mode)

- Verify Maven

Open command prompt (Windows) or Terminal (Mac/Linux) and run below command

$ mvn -v
Apache Maven 3.2.3 (bb52d8502b132ec0a5a3f4c09453c07478323dc5; 2015-11-10T09:41:47-07:00)
Maven home: /usr/local/Cellar/maven/3.2.3/libexec
Java version: 1.7.51_164, vendor: Oracle Corporation
Java home: /Library/Java/JavaVirtualMachines/jdk1.7.51_16.jdk/Contents/Home/jre
Default locale: en_US, platform encoding: UTF-8
OS name: "mac os x", version: "10.12.1", arch: "x86_64", family: "mac"

Warning: If any of the above dependencies are not met, please install them before proceed.

Clone or Download the code to desired directory. You can build the code using maven as below.

$ mvn clean install

Warning: If you are behind a corporate proxy and/or have a an enterprise maven repository, the build may fail as the dependencies that are present in the project might not be available. To fix this, you have to proxy the Enterprise Repo or update Enterprise repo with the required dependencies. To get all dependencies, run below command.

$ mvn dependency:tree

For first time install, the build will take some time as the project need to download all dependencies from Maven Central.

Run

The project use Jetty server for the development purpose. You can also deploy the code to any Servlet 3.0 supported containers like JBoss, Tomcat etc. To run the project execute below command.

$ mvn jetty:run

This will start the Jetty Server and deploy the code inside it. You can test the application using url http://localhost:8080/ems/

Database

As the project is using MYSQL InMemory database, there is no datasource setup required. All the database sqls (schema and data) are also part of the code. You can find in the db directory in resources folder.

The default port for the application is 8080, you can change that by supplying additional arguments during startup as below.

$ mvn jetty:run -Djetty.port=<port>

Application URL

Once the application is running, API endpoints are available at http://localhost:8080/ems/api

APIs

Getting Started

To access the APIs, the user should first register in the system. Once the user is successfully registered with the system, the system will provide an API Key which the user need to provide on the subsequent requests.

Some highlights:

• Request Id: Every API request is tagged with a unique Request ID, you'll be able to see that in the response header. This will offer additional help in debugging.
• Content Type: Every request is using application/json as content type.

Register

This will allow a user to register with the system

POST /api/registration/subscribe

Request body parameters

Name	Description	Type	Optional	Max Length
name	Name of the API consumer	String	No	50
email	Email id of the API consumer	String	No	50

Response

• HTTP Status 200
• apiKey - use this key for any future API access.

# Sample curl request
curl 'http://localhost:8080/ems/api/registration/subscribe' -H 'Content-Type: application/json' --data-binary $'{\n"name":"Gracy Dan",\n"email":"[email protected]"\n}'
# Sample Response
{"message":"Successfully added new user to the System","data":"API Key: 1724696d-e7c1-4c57-8a5f-35546abad15e"}

Add Employee

This will allow a registered user to add an Employee to the system.

POST /api/employee/add

Request body parameters

Name	Description	Type	Optional	Max Length
firstName	First Name of Employee	String	No	25
lastName	Last Name of the Employee	String	No	25
role	Employee Role Id in the company	Number	No	-
department	Department Id of Employee	Number	No	-
email	Email Id of the employee	String	No	50
birthDate	Birth date in YYYY-MM-DD format	Date	No	-
joinDate	Joining date in YYYY-MM-DD format	Date	No	-
gender	Gender of Employee	String	No	10
salary	Salary of Employee	Number	No	-

Response

• HTTP Status 201

# Sample curl request
curl 'http://localhost:8080/ems/api/employee/add' -H 'Content-Type: application/json' -H 'X-API-Key: 1724696d-e7c1-4c57-8a5f-35546abad15e' --data-binary $'{\n"firstName":"Gracy1",\n"lastName":"Dash1",\n"department": {\n\x09"departmentId": 1\n},\n"birthDate":"1990-01-08",\n"joinDate":"2012-02-05",\n"role": {\n\x09"roleId": 0\n},\n"gender":"Female",\n"salary": 54000,\n"email":"[email protected]"\n}'
# Sample Response
{"message":"Employee added to the system!","data":{"employeeId":100006,"firstName":"Gracy1","lastName":"Dash1","department":{"departmentId":1,"departmentName":null,"departmentDesc":null},"birthDate":"1990-01-07","joinDate":"2012-02-04","role":{"roleId":0,"roleName":null,"roleDescription":null},"gender":"Female","salary":54000,"email":"[email protected]"}}

Get Employee

This will allow a registered user to get/read an Employee using the employee id.

GET /api/employee/{id}

Request body parameters

Name	Description	Type	Optional	Max Length
id	Employee Id	Number	No	-

Response

• HTTP Status 200
• A valid Employee Object in JSON format.

# Sample curl request
curl 'http://localhost:8080/ems/api/employee/id/100004' -H 'Content-Type: application/json' -H 'X-API-Key: 1724696d-e7c1-4c57-8a5f-35546abad15e'
# Sample Response
{"message":null,"data":{"employeeId":100004,"firstName":"Gracy1","lastName":"Dash1","department":{"departmentId":1,"departmentName":null,"departmentDesc":null},"birthDate":"1990-01-07","joinDate":"2012-02-04","role":{"roleId":0,"roleName":null,"roleDescription":null},"gender":"Female","salary":54000,"email":"[email protected]"}}

Update Employee - Full

This will allow a registered user to update an Employee based on employee id. If you don't want to pass the complete object please see the next API.

PUT /api/employee/update/{id}

Request body parameters

Name	Description	Type	Optional	Max Length
employeeId	Employee ID on the system	Number	No	-
firstName	First Name of Employee	String	Yes	25
lastName	Last Name of the Employee	String	Yes	25
role	Employee Role Id in the company	Number	Yes	-
department	Department Id of Employee	Number	Yes	-
email	Email Id of the employee	String	Yes	50
birthDate	Birth date in YYYY-MM-DD format	Date	Yes	-
joinDate	Joining date in YYYY-MM-DD format	Date	Yes	-
gender	Gender of Employee	String	Yes	10
salary	Salary of Employee	Number	Yes	-

Response

• HTTP Status 200
• A updated Employee Object in JSON format.

# Sample curl request - Updaing the Email Address
curl --request PUT 'http://localhost:8080/ems/api/employee/update/100004' -H 'Content-Type: application/json' -H 'X-API-Key: 1724696d-e7c1-4c57-8a5f-35546abad15e --data-binary $'{\n"employeeId":100004,\n"firstName":"Gracy1",\n"lastName":"Dash1",\n"department": {\n\x09"departmentId": 1\n},\n"birthDate":"1990-01-08",\n"joinDate":"2012-02-05",\n"role": {\n\x09"roleId": 0\n},\n"email":"[email protected]"\n}'
# Sample response
{"message":"Employee data updated!","data":{"employeeId":100004,"firstName":"Gracy1","lastName":"Dash1","department":{"departmentId":1,"departmentName":null,"departmentDesc":null},"birthDate":"1990-01-07","joinDate":"2012-02-04","role":{"roleId":0,"roleName":null,"roleDescription":null},"gender":null,"salary":0,"email":"[email protected]"}}

Update Employee - Partial

This will allow a registered user to update an Employee based on employee id. If you are having the entire Employee object in your input, please see previous API details.

PATCH /api/employee/patch/{id}

Request body parameters

Name	Description	Type	Optional	Max Length
employeeId	Employee ID on the system	Number	No	-
firstName	First Name of Employee	String	Yes	25
lastName	Last Name of the Employee	String	Yes	25
role	Employee Role Id in the company	Number	Yes	-
department	Department Id of Employee	Number	Yes	-
email	Email Id of the employee	String	Yes	50
birthDate	Birth date in YYYY-MM-DD format	Date	Yes	-
joinDate	Joining date in YYYY-MM-DD format	Date	Yes	-
gender	Gender of Employee	String	Yes	10
salary	Salary of Employee	Number	Yes	-

Response

• HTTP Status 200
• A updated Employee Object in JSON format.

# Sample curl request
curl --request PATCH 'http://localhost:8080/ems/api/employee/patch/100004' -H 'Content-Type: application/json' -H 'X-API-Key: 1f0131b2-98c0-405d-9279-c6260d01ec46' --data-binary $'{\n"employeeId":100004,\n"department": {\n\x09"departmentId": 2\n}\n}'
# Sample response
{"message":"Employee data patched!","data":{"employeeId":100004,"firstName":"Gracy1","lastName":"Dash1","department":{"departmentId":2,"departmentName":null,"departmentDesc":null},"birthDate":"1990-01-07","joinDate":"2012-02-04","role":{"roleId":0,"roleName":null,"roleDescription":null},"gender":null,"salary":0,"email":"[email protected]"}}

Delete Employee

This will allow a registered user to delete an Employee based on employee id.

DELETE /api/employee/delete/{id}

Request body parameters

Name	Description	Type	Optional	Max Length
id	Employee Id	Number	No	-

Response

• HTTP Status 200

# Sample curl request
curl --request DELETE 'http://localhost:8080/ems/api/employee/delete/100005' -H 'Content-Type: application/json' -H 'X-API-Key: 1f0131b2-98c0-405d-9279-c6260d01ec46'
# Sample Response
{"message":"Employee data deleted successfully!"}

Response Errors

This section explains the generic errors, that are applicable to the API calls.

HTTP 401
API Key is not present. Use the header X-API-Key to provide the apiKey

This is due to the missing API Key. API Key obtained using POST /api/registration/subscribe has to supplied alongwith every other calls. You need to add the API Key as part of the header - X-API-Key

HTTP 401
Invalid Key provided : 3d35531a-6537-4b21-980b-b6dacac450ea

This is due to old/invalid key. Given that we are using an In-memory db, we need to register each time the application starts.

HTTP 422
<Validation Errors>

This can happen due to two conditions.
- Validation Failure - Validation present in certain fields. You'll be able to get specific details on the error message.
- Trying to add/modify/delete an Employee data with wrong employee id.

Next Steps...

• Cache Implementation - This will improve the system performance.
• Security using oAuth - As of now, the system uses a Static API key, we can enhance this by using oAuth.
• More APIs on Role, Department management.
• Improve Error management and add custom error messages