# Integrate using Eureka Rest APIs

You can use the Eureka Rest APIs explained [here](https://github.com/Netflix/eureka/wiki/Eureka-REST-operations).

**REST Endpoints Documentation**

**appID** is the name of the application and **instanceID** is the unique identifier associated with the instance. In AWS cloud, instanceID is the **instance id** of the instance and in other data centers, it is the **hostname** of the instance.

| ***Operation***                                  | ***HTTP action***                                                                                                                                                                                          | ***Description***                                                         |
| ------------------------------------------------ | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------- |
| Register new application instance                | <mark style="color:blue;">POST</mark> /eureka/apps/**appID**                                                                                                                                               | *Input*: JSON/XML payload *Output*: HTTP Code: 204 on success             |
| De-register application instance                 | <mark style="color:red;">DELETE</mark> /eureka/apps/appID/instanceID                                                                                                                                       | *Output*: HTTP Code: 200 on success                                       |
| Send application instance heartbeat              | <mark style="color:orange;">PUT</mark> /eureka/apps/**appID**/**instanceID**                                                                                                                               | *Output*: HTTP Code: 200 on *success* 404 if **instanceID** doesn't exist |
| Take instance out of service                     | <mark style="color:orange;">PUT</mark> /eureka/apps/**appID**/**instanceID**/status?value=OUT\_OF\_SERVICE                                                                                                 | *Output* HTTP Code: 200 on *success* 500 on *failure*                     |
| Move instance back into service (remove override | <mark style="color:red;">DELETE</mark> /eureka/apps/**appID**/**instanceID**/status?value=UP (The value=UP is optional, it is used as a suggestion for the fallback status due to removal of the override) | *Output* HTTP Code: 200 on *success* 500 on *failure*                     |
| Update metadata                                  | <mark style="color:orange;">PUT</mark> /eureka/apps/**appID**/**instanceID**/metadata?key=value                                                                                                            | *Output* HTTP Code: 200 on *success* 500 on *failure*                     |

For JSON/XML, the content types supplied must be **application/xml** or **application/json**.

When you register, you’ll need to post an XML (or JSON) body which conforms to this XSD:

```xml
<?xml version="1.0" encoding="UTF-8"?>
<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema" elementFormDefault="qualified" attributeFormDefault="unqualified">
    <xsd:element name="instance">
        <xsd:complexType>
            <xsd:all>
                <!-- hostName in ec2 should be the public dns name, within ec2 public dns name will
                     always resolve to its private IP -->
                <xsd:element name="hostName" type="xsd:string" />
                <xsd:element name="app" type="xsd:string" />
                <xsd:element name="ipAddr" type="xsd:string" />
                <xsd:element name="vipAddress" type="xsd:string" />
                <xsd:element name="secureVipAddress" type="xsd:string" />
                <xsd:element name="status" type="statusType" />
                <xsd:element name="port" type="xsd:positiveInteger" minOccurs="0" />
                <xsd:element name="securePort" type="xsd:positiveInteger" />
                <xsd:element name="homePageUrl" type="xsd:string" />
                <xsd:element name="statusPageUrl" type="xsd:string" />
                <xsd:element name="healthCheckUrl" type="xsd:string" />
               <xsd:element ref="dataCenterInfo" minOccurs="1" maxOccurs="1" />
                <!-- optional -->
                <xsd:element ref="leaseInfo" minOccurs="0"/>
                <!-- optional app specific metadata -->
                <xsd:element name="metadata" type="appMetadataType" minOccurs="0" />
            </xsd:all>
        </xsd:complexType>
    </xsd:element>

    <xsd:element name="dataCenterInfo">
        <xsd:complexType>
             <xsd:all>
                 <xsd:element name="name" type="dcNameType" />
                 <!-- metadata is only required if name is Amazon -->
                 <xsd:element name="metadata" type="amazonMetdataType" minOccurs="0"/>
             </xsd:all>
        </xsd:complexType>
    </xsd:element>

    <xsd:element name="leaseInfo">
        <xsd:complexType>
            <xsd:all>
                <!-- (optional) if you want to change the length of lease - default if 90 secs -->
                <xsd:element name="evictionDurationInSecs" minOccurs="0"  type="xsd:positiveInteger"/>
            </xsd:all>
        </xsd:complexType>
    </xsd:element>

    <xsd:simpleType name="dcNameType">
        <!-- Restricting the values to a set of value using 'enumeration' -->
        <xsd:restriction base = "xsd:string">
            <xsd:enumeration value = "MyOwn"/>
            <xsd:enumeration value = "Amazon"/>
        </xsd:restriction>
    </xsd:simpleType>

    <xsd:simpleType name="statusType">
        <!-- Restricting the values to a set of value using 'enumeration' -->
        <xsd:restriction base = "xsd:string">
            <xsd:enumeration value = "UP"/>
            <xsd:enumeration value = "DOWN"/>
            <xsd:enumeration value = "STARTING"/>
            <xsd:enumeration value = "OUT_OF_SERVICE"/>
            <xsd:enumeration value = "UNKNOWN"/>
        </xsd:restriction>
    </xsd:simpleType>

    <xsd:complexType name="amazonMetdataType">
        <!-- From <a class="jive-link-external-small" href="http://docs.amazonwebservices.com/AWSEC2/latest/DeveloperGuide/index.html?AESDG-chapter-instancedata.html" target="_blank">http://docs.amazonwebservices.com/AWSEC2/latest/DeveloperGuide/index.html?AESDG-chapter-instancedata.html</a> -->
        <xsd:all>
            <xsd:element name="ami-launch-index" type="xsd:string" />
            <xsd:element name="local-hostname" type="xsd:string" />
            <xsd:element name="availability-zone" type="xsd:string" />
            <xsd:element name="instance-id" type="xsd:string" />
            <xsd:element name="public-ipv4" type="xsd:string" />
            <xsd:element name="public-hostname" type="xsd:string" />
            <xsd:element name="ami-manifest-path" type="xsd:string" />
            <xsd:element name="local-ipv4" type="xsd:string" />
            <xsd:element name="hostname" type="xsd:string"/>
            <xsd:element name="ami-id" type="xsd:string" />
            <xsd:element name="instance-type" type="xsd:string" />
        </xsd:all>
    </xsd:complexType>

    <xsd:complexType name="appMetadataType">
        <xsd:sequence>
            <!-- this is optional application specific name, value metadata -->
            <xsd:any minOccurs="0" maxOccurs="unbounded" processContents="skip"/>
        </xsd:sequence>
    </xsd:complexType>

</xsd:schema>
```

**Examples**

**RENEW / HEARTBEAT**

Example : <mark style="color:orange;">`PUT`</mark>` ``/eureka/apps/MYAPP/i-6589ef6`

Response Status:

* <mark style="color:green;">`200`</mark> (on success)
* <mark style="color:orange;">`404`</mark> (eureka doesn't know about you, Register yourself first)
* <mark style="color:red;">`500`</mark> (failure)

(If Eureka doesn't get heartbeats from the service node within the evictionDurationInSecs, then the node will get automatically de-registered )

**CANCEL**

Example : <mark style="color:red;">`DELETE`</mark>` ``/eureka/apps/MYAPP/i-6589ef6`

Response Status:

* <mark style="color:green;">`200`</mark> (on success)
* <mark style="color:red;">`500`</mark> (failure)