Quick Start Guide

WSO2 API Manager is a complete solution for publishing APIs, creating and managing a developer community and for routing API traffic in a scalable manner. It leverages the integration, security and governance components from the WSO2 Enterprise Service Bus, WSO2 Identity Server, and WSO2 Governance Registry. In addition, as it is powered by the WSO2 Business Activity Monitor (BAM), the WSO2 API Manager is ready for massively scalable deployment immediately.

This guide walks you thorough the main use cases of the API Manager:

Introduction to basic concepts

Let's take a look at the basic concepts that you need to know before using the API Manager.

Components

The API Manager comprises the following components:

• API Gateway : Secures, protects, manages, and scales API calls. It is a simple API proxy that intercepts API requests and applies policies such as throttling and security checks. It is also instrumental in gathering API usage statistics. The Web interface can be accessed via https://<Server Host>:9443/carbon.
• API Key Manager : Handles all security and key-related operations. API gateway connects with the key manager to check the validity of OAuth tokens when APIs are invoked. Key Manager also provides a token API to generate OAuth tokens that can be accessed via the Gateway.
• API Publisher : Enables API providers to publish APIs, share documentation, provision API keys, and gather feedback on API features, quality and usage. The Web interface can be accessed via https://<Server Host>:9443/publisher.
• API Store : Enables API consumers to self register, discover API functionality, subscribe to APIs, evaluate them and interact with API publishers. The Web interface can be accessed via https://<Server Host>:9443/store.
• Additionally, statistics are provided by the monitoring component, which integrates with WSO2 BAM.

Users and roles

The API manager offers three distinct community roles that are applicable to most enterprises:

• Creator : a creator is a person in a technical role who understands the technical aspects of the API (interfaces, documentation, versions, how it is exposed by API Gateway) and uses the API publisher to provision APIs into the API store. The creator uses the API Store to consult ratings and feedback provided by API users. Creator can add APIs to the store but cannot manage their lifecycle (i.e., make them visible to the outside world).
• Publisher : a publisher manages a set of APIs across the enterprise or business unit and controls the API lifecycle and monetization aspects. The publisher is also interested in usage patterns for APIs and as such has access to all API statistics.
• Consumer : a consumer uses the API store to discover APIs, see the documentation and forums and rate/comment on the APIs. S/he subscribes to APIs to obtain API keys.

API lifecycle

An API is the published interface, while the service is the implementation running in the backend. APIs have their own lifecycles that are independent to the backend services they rely on. This lifecycle is exposed in the API publisher Web interface and is managed by the API publisher role.

The following stages are available in the default API life cycle:

• CREATED : API metadata is added to the API Store, but it is not visible to subscribers yet, nor deployed to the API gateway
• PROTOTYPED : API is deployed and published in the API Store as a prototype. A prototyped API is usually a mock implementation made public in order to get feedback about its usability. Users cannot subscribe to a prototyped API. They can only try out its functionality.
• PUBLISHED : API is visible in the API Store and available for subscription.
• DEPRECATED : API is still deployed into the API Gateway (i.e., available at runtime to existing users) but not visible to subscribers. An API can automatically be deprecated when a new version is published.
• RETIRED : API is unpublished from the API gateway and deleted from the store
• BLOCKED : Access is temporarily blocked. Runtime calls are blocked and the API is not shown in the API Store anymore.

You can manage the API and service lifecycles in the same governance registry/repository and automatically link them. This feature is available in WSO2 Governance Registry (version 4.5 onwards).

Applications

An application is primarily used to decouple the consumer from the APIs. It allows you to :

• Generate and use a single key for multiple APIs
• Subscribe multiple times to a single API with different SLA levels

You create an application to subscribe to an API. The API Manager comes with a default application and you can also create as many applications as you like.

Throttling tiers

Throttling tiers are associated to an API at subscription time. They define the throttling limits enforced by the API gateway. E.g., 10 TPS (transactions per second). You define the list of tiers that are available for a given API at the publisher level. The API Manager comes with three predefined tiers (Gold/Silver/Bronze) and a special tier called Unlimited, which can be disabled by editing the <TierManagement> element of <APIM_HOME>/repository/conf/api-manager.xml file. To edit existing tiers or create your own tiers, see Adding new Throttling Tiers.

API keys

The API Manager supports two scenarios for authentication:

1. An access token is used to identify and authenticate a whole application
2. An access token is used to identify the final user of an application (for example, the final user of a mobile application deployed on many different devices)

Application access token

Application access tokens are generated by the API consumer and must be passed in the incoming API requests. The API Manager uses OAuth2 standard to provide key management. The API key is a simple string that you pass to an HTTP header (e.g., "Authorization: Bearer NtBQkXoKElu0H1a1fQ0DWfo6IX4a") and it works equally well for SOAP and REST calls.

Application access tokens are generated at the application level and valid for all APIs that are associated to the application. These tokens have a fixed expiration time, which is set to 60 minutes by default. You can change this to a longer time, even for several weeks. Consumers can re-generate the access token directly from the API Store Web interface. To change the default expiration time, you open <APIM_HOME>/repository/conf/identity.xml file and change the value for element <ApplicationAccessTokenDefaultValidityPeriod>. You set a negative value to <ApplicationAccessTokenDefaultValidityPeriod> element to never expire the application access token.

Application user access token

You can generate access tokens on demand using the token API. In case a token expires, you use the token API to refresh it.

Application user access tokens have a fixed expiration time, which is 60 minutes by default. You can update it to a longer time, such as several weeks, by editing the <ApplicationAccessTokenDefaultValidityPeriod> element in <APIM_HOME>/repository/conf/identity.xml file.

The token API takes the following parameters to generate the access token:

• Grant Type
• Username
• Password
• Scope

To generate a new access token, you issue a token API call with the above parameters where grant_type=password. The Token API then returns two tokens: an access token and a refresh token. The access token can then be stored in a session on the client side (the application itself does not need to manage users and passwords). On the API Gateway side, the access token is validated for each API call. When the token expires, you refresh the token by issuing a token API call with the above parameters where grant_type=refresh_token and passing the refresh token as a parameter.

API Resources

Starting the API Manager

1. Download WSO2 API Manager from http://wso2.com/products/api-manager/.
2. Install Oracle Java SE Development Kit (JDK) version 1.6.24 or later or 1.7.*.
3. Set the JAVA_HOME environment variable.
4. Using the command line, go to <Installation directory>/bin and execute wso2server.bat (for Windows) or wso2server.sh (for Linux).
5. Wait until you see the message "WSO2 Carbon started in 'n' seconds."
   
   It indicates that the server started successfully. To stop the API Manager, simply hit Ctrl-C in the command window.

Creating users and roles

In section Users and roles, we introduced you to a set of users that are commonly found in many enterprises. To create these users in the API Manager, you log in to the management console as an administration user (credentials: admin/admin). The admin use can play the creator, publisher and subscriber roles described earlier. In this section, we explain how to set up these users or custom users and roles.

1. Log in to the management console user interface (https://<hostname>:9443/carbon) of the API Manager using admin/admin credentials.

2. Select the Users and Roles menu under the Configure menu.
3. Click Add New Role and provide creator as the role name.
4. Click Next.
5. Select the following permissions from the list that opens and click Finish.
   
   • Configure > Governance and all underlying permissions.
   • Login
   • Manage > API > Create  
   • Manage > Resources > Govern and all underlying permissions    

6. Similarly, create the publisher role with the following permissions.

   • Login
   • Manage > API > Publish

   Tip: As the subscriber role is available in the API Manager by default, you do not have to create it. If you want to create a new role with subscriber permissions, you can do so with the following permissions.

   1. • Login
      • Manage > API > Subscribe
7. You can now create users for each of those roles. To do so, click the Users and Roles menu under the Configure menu.
8. Click Users.
9. Click Add New User, provide the username/password and click Next.

10. Select the role you want to assign to the user (e.g., creator, publisher or subscriber) and click Finish. Given below is a list of usernames and the roles we assign to them in this guide.

    Username	Role
    apicreator	creator
    apipublisher	publisher

    Repeat the steps to create at least one user for all roles.

Creating an API

An API creator uses the API provider Web application to create and publish APIs into the API Store. In this section, we explain how to create an API and attach documentation to it.

In this guide, we work with a service exposed by the Cdyne services provider (www.cdyne.com). We use their phone validation service, which has SOAP and REST interfaces and is documented using a WSDL file. This service is documented at : http://wiki.cdyne.com/index.php/Phone_Verification.

Let's create this API and add it to the API Store.

1. Open the API Publisher (https://<hostname>:9443/publisher) and log in as apicreator.

2. Click the Add link and provide the information given in the table below.
   
   

   Field	Value	Description
   Name	PhoneVerification	Name of API as you want it to appear in the API store
   Context	/phoneverify	URI context path that is used by to API consumers
   Version	1.0.0	API version (in the form of version.major.minor)

3. Under the Resources section, create a resource by the name CheckPhoneNumber and select its GET, POST and OPTIONS methods. Once you are done, click Implement.

   Tip: Selecting the OPTIONS method is mandatory if you want to allow subscribers to invoke the API using the API Console, which is in the API Store.

   

4. The Implement tab opens. Provide the following information.

   

   Field	Value	Description
   Implementation method	Backend endpoint	If you have a real backend implementation to your API, select that option. Else, you can specify implementation in-line. The latter approach is usually used in mock-up implementation for prototyped APIs.
   Endpoint type	HTTP endpoint
   Production endpoint	http://ws.cdyne.com/phoneverify/phoneverify.asmx
   Endpoint security scheme	Non Secured	If the endpoint is secured, user is asked for credentials of the backend service.

5. Click Manage to go to the Manage tab and provide the following information.

   

   Field	Value	Description
   Tier Availability	Bronze/Gold/Silver/Unlimited	The API can be available at different level of service; you can select multiple entries from the list. At subscription time, the consumer chooses which tier they are interested in.
   Transports	HTTP/HTTPS

   Tip: For resources that have methods requiring authentication (i.e., Auth Type is not NONE), you set  None  as the Auth type of  OPTIONS  to support CORS (Cross Origin Resource Sharing) between the API Store and Gateway.

Adding API documentation

1. After creating the API, click on its icon to open its details. Select the Docs tab.

2. Click Add New Document link.

   Documentation can be provided inline, via a URL or as a file. For inline documentation, you can edit the content directly from the API publisher interface. You get several documents types:

   • How To
   • Samples and SDK
   • Public forum / Support forum (external link only)
   • API message formats
   • Other
3. Select the How To type, a name for the document and a short description, which will appear in the API Store. Select inline or provide a URL.
4. Click Add Document.

5. Once the document is added, click Edit Content link, which opens an embedded editor to edit the document contents.

Versioning the API

Next, we will create a new version of this API.

1. Log in to the API Publisher as apicreator if you are not logged in already.
2. Click on the PhoneVerification API and then the Copy button that appears in its Overview tab.
   
3. Specify a new version number in version.major.minor format (e.g., 2.0.0) and click Done.

A new version of the API is created. It is a duplication of all the contents of the original API, including the documentation. The API is now ready to be published. This is done by a user in the publisher role.

Publishing the API

1. Log in to the API Publisher Web application as apipublisher.
2. Click on the PhoneVerification API version 1.1.0 that you created before. Note that you can now see a tab as API Lifecycle in the API Publisher UI.
3. Go to the Lifecycle tab and select the state as PUBLISHED from the drop-down list.
   
   
   • Propagate Changes to API Gateway: Used to define an API proxy in the API Gateway runtime component, allowing the API to be exposed to the consumers via the API Gateway. If this option is left unselected, the API metadata will not change and you will have to manually configure the API Gateway according to the information published in the API Store.
   • Deprecate Old Versions: If selected, any prior versions of the API will be set to the DEPRECATED state automatically.
   • Require Re-Subscription: Invalidates current user subscriptions, forcing users to subscribe again.

Subscribing to the API

You subscribe to APIs using the API Store Web application.

1. Open the API Store (https://<hostname>:9443/store) using your browser.

2. The API you published earlier is available in the API Store. Self sign up to the API Store using the Sign-up link.
   

3. After subscription, log in to the API Store and click the API you published earlier (PhoneVerification 2.0.0).

4. Note that you can see the subscription option in the right hand side of the UI after logging in. Select the default application and Bronze tier, and click Subscribe.
   

   Applications

   An application is a logical collection of one or more APIs, and is required when subscribing to an API. You can subscribe to multiple APIs using the same application. Instead of using the default application, you can also create your own by selecting the New Application... option in the above drop-down list or by going to the My Applications menu in the top menu bar.

5. Once the subscription is successful, go to My Subscriptions page.
6. In the My Subscriptions page, click the Generate buttons to generate production and sandbox access tokens and consumer key/secret pairs for the API.
   

Invoking the API

To invoke an API, you can use the integrated Swagger interactive documentation support (or any other simple REST client application or curl).

1. Log in to the API Store (https:/ /<YourHostName>:9443/store).

2. Click the APIs menu in the API Store and then click on the API that you want to invoke. When the API opens, go to its API Console tab.
   

3. Note the changes you did in the Swagger definition earlier displayed on the console. For example, expand the GET method and see the two parameters that you added:
   
   Let's invoke this API using the API Console.

4. Click the GET method, provide the required parameters and click Try it Out . The parameters you give here change depending on the backend implementation of the API. 

   Query Parameters	E.g., PhoneNumber=18006785432&LicenseKey=0
   Authorization	The API console is automatically populated by the access token that you generated in step 9 after subscribing to the API.
   Base URL	Appears at the bottom of the console. Using the base URL and the parameters, the system creates the API URL in the form http://<host_name>:8280/<context>/<version>/<Resource, if any><back end service requirements included as parameters, if any>. For example, http://localhost:8280/phoneverify/2.0.0/CheckPhoneNumber. /phoneverify is the context, 2.0.0 is the version, and CheckPhoneNumber is the resource. If you cannot invoke the API's HTTPS endpoint (causes the SSLPeerUnverified exception), it could be because the security certificate issued by the server is not trusted by your browser. To resolve this issue, access the HTTPS endpoint directly from your browser and accept the security certificate.

    

5. Note the response for the API invocation. As we used a valid phone number in this example, the response is valid.
   

 You have invoked an API using the Swagger API console.

Monitoring APIs and viewing statistics

Both the API publisher and store provide several statistical dashboards. Some of them are as follows:

• Number of subscriptions per API (across all versions of an API)
• Number of API calls being made per API (across all versions of an API)
• The subscribers who did the last 10 API invocations and the APIs/versions they invoked

• Usage of an API and from which resource path (per API version)

• Number of times a user has accessed an API
• The number of API invocations that failed to reach the endpoint per API per user
• API usage per application
• Users who make the most API invocations, per application
• API usage from resource path, per application

Configuring statistics

Do the following if you are on a Windows environment:

• JDK 1.6.* or 1.7

  If you install JDK in Program Files in the Windows environment, avoid the space by using PROGRA~1 when specifying environment variables for JAVA_HOME and PATH. Else, the server throws an exception.

• Cygwin (http://www.cygwin.com): This is required only if you are using Windows. WSO2 BAM analytics framework depends on Apache Hadoop, which requires Cygwin in order to run on Windows. Install at least the basic net (OpenSSH,tcp_wrapper packages) and security related Cygwin packages. After Cygwin installation, update the PATH variable with C:/cygwin/bin and restart BAM.

Steps below explain how to configure WSO2 BAM 2.4.1 with the API Manager.

1. Do the following changes in <APIM_HOME>/repository/conf/api-manager.xml file:

   • Enable API usage tracking by setting the <APIUsageTracking> element to true
   • Set the Thrift port to 7614
   • Uncomments and set the data source used for getting BAM statistics in <DataSourceName> element.
   • Set <BAMServerURL> to tcp://<BAM host IP>:7614/ where <BAM host IP> is the machine IP address. Do not use localhost unless you're in a disconnected mode.

   <APIUsageTracking>
       <!-- Enable/Disable the API usage tracker. -->
       <Enabled>true</Enabled>   
       <PublisherClass>org.wso2.carbon.apimgt.usage.publisher.APIMgtUsageDataBridgeDataPublisher</PublisherClass>
       <ThriftPort>7614</ThriftPort> 
       <BAMServerURL>tcp://<BAM host IP>:7614/</BAMServerURL>
       <BAMUsername>admin</BAMUsername>
       <BAMPassword>admin</BAMPassword>
       <!-- JNDI name of the data source to be used for getting BAM statistics. This data source should
           be defined in the master-datasources.xml file in conf/datasources directory. -->
       <DataSourceName>jdbc/WSO2AM_STATS_DB</DataSourceName>
   </APIUsageTracking>

2. Specify the datasource definition in <APIM_HOME>/repository/conf/datasources/master-datasources.xml file as follows. 
   

   <datasource>
             <name>WSO2AM_STATS_DB</name>
             <description>The datasource used for getting statistics to API Manager</description>
             <jndiConfig>
                <name>jdbc/WSO2AM_STATS_DB</name>
             </jndiConfig>
             <definition type="RDBMS">
                <configuration>
                    <!-- JDBC URL to query the database -->
                    <url>jdbc:h2:<BAM_HOME>/repository/database/APIMGTSTATS_DB;AUTO_SERVER=TRUE</url>
                    <username>wso2carbon</username>
                    <password>wso2carbon</password>
                    <driverClassName>org.h2.Driver</driverClassName>
                    <maxActive>50</maxActive>
                    <maxWait>60000</maxWait>
                    <testOnBorrow>true</testOnBorrow>
                    <validationQuery>SELECT 1</validationQuery>
                    <validationInterval>30000</validationInterval>
               </configuration>
            </definition>
   </datasource>

   
   Next, prepare BAM to collect and analyze statistics from API manager.

3. Download WSO2 BAM 2.4.1 or later from location: http://wso2.com/products/business-activity-monitor.

4. Change port offset of BAM to 3 by editing the file <BAM_HOME>/repository/conf/carbon.xml file (search for the offset node).

   <Offset>3</Offset>

   This increments all ports used by the server by 3, which means the BAM server will run on port 9446. Port offset is used to increment the default port by a given value. It avoids possible port conflicts when multiple WSO2 products run in same host.

5. Do the following changes in <BAM_HOME>/repository/conf/datasources/bam_datasources.xml file:
   • Copy/paste WSO2_AMSTATS_DB definition from API Manager's master-datasources.xml file. You edited it in step 2.

   • Replace the port of WSO2BAM_CASSANDRA_DATASOURCE in URL (jdbc:cassandra://localhost:9163/EVENT_KS). Note that localhost is used here; not the machine IP.

     • Do not edit the WSO2BAM_UTIL_DATASOURCE, which is using the offset
     • Cassandra is bound by default on localhost, unless you change the data-bridge/data-bridge-config.xml file
6. Copy the file <APIM_HOME>/statistics/API_Manager_Analytics.tbox to directory <BAM_HOME>/repository/deployment/server/bam-toolbox.
   
   If this folder is not in the BAM installation directory by default, create it. The toolbox describes the information collected, how to analyze the data, as well as the location of the database where the analyzed data is stored.

7. Open <BAM_HOME>/repository/conf/etc/hector-config.xml file and change the port to localhost:9163. You must add the other nodes too when configuring a clustered setup.

   <Nodes>localhost:9163</Nodes>

8. Restart the BAM server by running <BAM_HOME>/bin/wso2server.[sh/bat].

Viewing statistics

This concludes the API Manager quick start. You have set up the API Manager and taken a look at its common usecases. For more advanced usecases, please see the User Guide and the Admin Guide of the API Manager documentation.