FAQ

About WSO2 API Manager

What is WSO2 API Manager?

WSO2 API Manager is a complete solution for creating, publishing and managing all aspects of an API and its life cycle. See the introduction.

What is the open source license of the API Manager?

Apache Software License Version 2.0

Is there commercial support available for WSO2 API Manager?

It is completely supported from evaluation to production. See WSO2 Support.

What are the default ports opened in the API Manager?

See Default Ports of WSO2 Products.

What are the technologies used underneath WSO2 API Manager?

The API Manager is built on top of WSO2 Carbon, an OSGi based components framework for SOA. See components.

Can I get involved in APIM development activities?

Not only are you allowed, but also encouraged. You can start by subscribing to dev@wso2.org and architecture@wso2.org mailing lists. Feel free to provide ideas, feedback and help make our code better. For more information on contacts, mailing lists and forums, see our support page.

What is the default communication protocol of the API Manager?

The default communication protocol is Thrift.

Installation and start up

What are the minimum requirements to run WSO2 API Manager?

Minimum requirement is Oracle Java SE Development Kit (JDK). See Installation Prerequisites.

What Java versions are supported by the API Manager?

Oracle JDK versions 1.7.*/1.8.*.

Which MySQL database script should I use?

From Carbon kernel 4.4.6 onward your product is shipped with two scripts for MySQL as follows (click here to see if your product is based on this kernel version or newer):

mysql.sql : Use this script for MySQL versions prior to version 5.7.
mysql5.7.sql : Use this script for MySQL 5.7 and later versions.

Note that if you are automatically creating databases during server startup using the -DSetup option, the mysql.sql script will be used by default to set up the database. Therefore, if you have MySQL version 5.7 set up for your server, be sure to do the following before starting the server:

First, change the existing mysql.sql file to a different filename.
Change the <PRODUCT_HOME>/dbscripts/mysql5.7.sql script to mysql.sql.
Change the <PRODUCT_HOME>/dbscripts/identity/mysql5.7.sql script to mysql.sql.

MySQL 5.7 is only recommended for products that are based on Carbon 4.4.6 or a later version.

How do I deploy a third-party library into the API Manager?

Copy any third-party JARs to <APIM_HOME>/repository/components/lib directory and restart the server.

Is it possible to connect the API Manager directly to an LDAP or Active Directory where the corporate identities are stored?

Yes. You can configure the API Manager with multiple user stores. See Configuring User Stores.

Can I extend the management console UI to add custom UIs?

Yes, you can extend the management console (default URL is https://localhost:9443/carbon) easily by writing a custom UI component and simply deploying the OSGi bundle.

I don't want some of the features that come with WSO2 API Manager. Can I remove them?

Yes, you can do this using the Features menu under the Configure menu of the management console (default URL is https://localhost:9443/carbon).

How can I change the memory allocation for the API Manager?

The memory allocation settings are in <APIM_HOME>/bin/wso2server.sh file.

I don't want all the components of the API Manager up when I start the server. How do I start up only selected ones?

Even though the API Manager bundles all components together, you can select which component/s you want to start by using the -Dprofile command at product startup. See Product Profiles for more information.

Deployment

Where can I look up details of different deployment patterns and clustering configurations of the API Manager?

See Deploying WSO2 API Manager.

What are the container technologies that are supported in API Manager?

OpenShift, Docker, Kubernetes and Mesos are supported.

What is the recommended way to manage multiple artifacts in a product cluster?

For artifact governance and lifecycle management, we recommend you to use a shared WSO2 Governance Registry instance.

Is it recommended running multiple WSO2 products on a single server?

This is not recommended in a production environment involving multiple transactions. If you want to start several WSO2 products on a single server, you must change their default ports to avoid port conflicts. See Changing the Default Ports with Offset.

Can I install features of other WSO2 products to the API Manager?

Yes, you can do this using the management console. The API Manager already has features of WSO2 Identity Server, WSO2 Governance Registry, WSO2 ESB etc. embedded in it. However, if you require more features of a certain product, it is recommended to use a separate instance of it rather than install its features to the API Manager.

How can I continue to use my email address as the username in a distributed API-M deployment?

To enable using your email (e.g., admin@wso2.com) as your username when deploying WSO2 API-M and WSO2 Identity Server (WSO2 IS), while doing master configurations, do the following.

Go to <API-M_HOME>/repository/conf/api-manager.xml. In the DataPublisher section, under ThrottlingConfiguration section, specify the username as follows: admin@wso2.com@carbon.super The api-manager.xml file accepts only configurations for the super tenant.

<Username>admin@wso2.com@carbon.super</Username>

For more details, see Using Email Address as the Username.

How can I set up a reverse proxy server to pass server requests?

See Adding a Reverse Proxy Server.

Functionality

I cannot see all the APIs that I published on the API Store. Why is this?

If you have multiple versions of an API published, only the latest version is shown in the API Store. To display multiple versions, set the <DisplayMultipleVersions> element to true in <APIM_HOME>/repository/conf/api-manager.xml file.

When editing an API's resource's parameters, how can I add multiple options to the parameter Response Content Type ?

You cannot do this using the UI. Instead, edit the Swagger definition of the API as content_type: ["text/xml","text/plain"] for example.

Why are the changes I did to the resource parameter `Response Content Type` of a published API not reflected in the API Store after saving?

If you edited the Response Content Type using the UI, please open the API's Swagger definition, do your changes and save. Then the changes should be reflected back in the API Store. This will be fixed in a future release.

How can I add more features to the API Manager server and extend its functionality?

You can install any WSO2 component to the API Manager. See the Installing Features section in the WSO2 Carbon docs for more information.

How do I change the pass-through transport configurations?

If you have enabled the pass-through transport, you can change its default configurations by adding the following under the <transportReceiver name="https" class="org.apache.synapse.transport.passthru.PassThroughHttpSSLListener"> element in the <PRODUCT_HOME>/repository/conf/axis2/axis2.xml file. Be sure to stop the server before editing the file.

If you are using JDK 1.7.* or 1.8.*, add the parameter given below:

<transportReceiver name="passthru-https" class="org.wso2.carbon.transport.passthru.PassThroughHttpSSLListener"> 
    <parameter name="HttpsProtocols">TLSv1,TLSv1.1,TLSv1.2</parameter> 
    ...... 
</transportReceiver>

If I want to extend the default API Manager server by installing new features, how can I do it?

See Working with Features in the WSO2 Carbon documentation.

How can I preserve the CDATA element tag in API responses?

Set the javax.xml.stream.isCoalescing property to false in the <APIM_HOME>/XMLInputFactory.properties file. Here's an example:

<XacuteResponse xmlns="http://aaa/xI">
   <Rowset>
       <Row>
          <outxml><![CDATA[<inSequence>
            <send>
               <endpoint>
                  <address uri="http://localhost:8080/my-webapp/echo"/>
               </endpoint>
            </send>
         </inSequence>]]></outxml>
       </Row>
    </Rowset>
</XacuteResponse>

Authentication and security

How can I manage authentication centrally in a clustered environment?

You can enable centralized authentication using a WSO2 Identity Server based security and identity gateway solution, which enables SSO (Single Sign On) across all the servers.

How can I manage the API permissions/visibility?

To set visibility of the API only to selected user roles in the server, see API Visibility.

How can I add security policies (UT, XACML etc.) for the services?

This should be done in the backend services in the Application Server or WSO2 ESB.

How can I enable self signup to the API Store?

See how to enable self signup.

How can I disable self signup capability to the API Store? I want to engage my own approval mechanism.

To disable the self signup capability, open the APIM management console and click the Resources -> Browse menu. The registry opens. Navigate to /_system/governance/apimgt/applicationdata/sign-up-config.xml and set <SelfSignUp><Enabled> element to false. To engage your own signup process, see Adding a User Signup Workflow.

Is there a way to lock a user's account after a certain number of failed login attempts to the API Store?

If your identity provider is WSO2 Identity Server, this facility comes out of the box. If not, install the Account Recovery and Credentials Management feature (Available under User Management category) to the API Manager and configure it. For information, see User Account Locking and Account Disabling page in the Identity Server documentation. For more information on installing features, see Feature Installation documentation.

Is there a way to recover a forgotten password for a API store user?

In order to recover a password of a store user, you need to enable the password recovery feature. By default the feature will not work, as an email server is not conifgured.Follow the steps below to properly configure the forgotten password feature.

Open the <APIM_HOME>repository/conf/axis2/axis2.xml and uncomment the following tag and configure a mail server. Refer to MailTo Transport for more information.
```
<transportSender name="mailto" class="org.apache.axis2.transport.mail.MailTransportSender">
```
Now you have the configured set up. Now a user can click on the forgot password link on the login page of the API Store.
You need to have a user account with an email configured for this feature to work.Once you click on the Forgot Password link you will be redirected to add the username of the user you are trying to recover the password of.
Once you add the username and click on Request Password Change, you will recieve a notification mentioning that instructions have been sent to your pre configured email address.
You would receive an email with the following information. Click on the link given.

If you need to change the template of the email, i.e the email link, wording etc, you need to open the <APIM_HOME>/repository/conf/email/email-admin-config.xml file and change the template.
Once you click on the link, you will be redirected to a change password page, where you can change your password.
Now you can use the changed password to sign in.

How do I change the default admin password and what files should I edit after changing it?

To change the default admin password, log in to the management console with admin/admin credentials and use the "Change my password" option. After changing the password, do the following:

Change the following elements in <APIM_HOME>/repository/conf/api-manager.xml file:

<AuthManager>
   <Username>admin</Username>
   <Password>newpassword</Password>
</AuthManager>

<APIGateway>
   <Username>admin</Username>
   <Password>newpassword</Password>
</APIGateway>

<APIKeyManager>
   <Username>admin</Username>
   <Password>newpassword</Password>
</APIKeyManager>

Go to the Resources -> Browse menu in the management console to open the registry and update the credentials in /_system/governance/apimgt/applicationdata/sign-up-config.xml registry location.

How can I recover the admin password used to log in to the management console?

Use <APIM_HOME>/bin/chpasswd.sh script.

How can I manage session timeouts for the management console?

To configure session timeouts, see Configuring the session time-out.

How can I add the authentication headers to the message going out of the API Gateway to the backend?

Uncomment the <RemoveOAuthHeadersFromOutMessage> element in the <APIM_HOME>/repository/conf/api-manager.xml file and set its value to false.

Can I give special characters in the passwords that appear in the configuration files?

If the config file is in XML, take care when giving special characters in the user names and passwords. According to XML specification (http://www.w3.org/TR/xml/), some special characters can disrupt the configuration. For example, the ampersand character (&) must not appear in the literal form in XML files. It can cause a Java Null Pointer exception. You must wrap it with CDATA (http://www.w3schools.com/xml/xml_cdata.asp) as shown below or remove the character:

<Password>
    <![CDATA[xnvYh?@VHAkc?qZ%Jv855&A4a,%M8B@h]]>
</Password>

How to protect my product server from security attacks caused by weak ciphers such as the Logjam attack (Man-in-the-Middle attack)?

You can disable weak ciphers as described in Disable weak ciphers in the WSO2 Carbon documentation.

Troubleshooting

Why do I get the following warning: org.wso2.carbon.server.admin.module.handler.AuthenticationHandler - Illegal access attempt while trying to authenticate APIKeyValidationService?

Did you change the default admin password?
If so, you need to change the credentials stored in the <APIKeyValidator> element of the <APIM_HOME>/repository/conf/api-manager.xml file of the API Gateway node/s.

Have you set the priority of the SAML2SSOAuthenticator handler higher than that of the BasicAuthenticator handler in the authenticators.xml file?
If so, the SAML2SSOAuthenticator handler tries to manage the basic authentication requests as well. Set a lower priority to the SAML2SSOAuthenticator than the BasicAuthenticator handler as follows:

<Authenticator name="SAML2SSOAuthenticator" disabled="false">
   <Priority>0</Priority>
   <Config>
      <Parameter name="LoginPage">/carbon/admin/login.jsp</Parameter>
      <Parameter name="ServiceProviderID">carbonServer</Parameter>
      <Parameter name="IdentityProviderSSOServiceURL">https://localhost:9444/samlsso</Parameter>
      <Parameter name="NameIDPolicyFormat">urn:oasis:names:tc:SAML:1.1:nameid-format:unspecified</Parameter>
      <Parameter name="ISAuthnReqSigned">false</Parameter>
      <!-<Parameter name="AssetionConsumerServiceURL">https://localhost:9443/acs</Parameter>->
   </Config>
</Authenticator>

How can I fix the javax.net.ssl.SSLException: hostname in certificate didn't match: <ip addrees> != <localhost> exception?

Reason for occurrence

The javax.net.ssl.SSLException: hostname in certificate didn't match: <ip addrees> != <localhost> exception is a very common exception that occurs whenever the WSO2 product server is accessed using a different IP address (e.g., https://10.100.0.77:9443/publisher) except localhost (e.g., https://localhost:9443/publisher).

The reason that the latter mentioned exception occurs is because the self-signed certificate that is shipped with WSO2 products is configured using the hostname as localhost, as a result, Apache Shindig does not allow any other HTTP requests that originate from other hostnames/IP addresses other than localhost.

Overcoming the issue

You have to create and add a certificate for the IP/domain name in order to overcome this issue. Follow the instructions below:

In the following instructions, assume that you are attempting to add a self-signed certificate for the domain 'foo.com'.

Step 1 - Create a self-signed Java KeyStore file and include your domain as the Common Name (CN)

Open a terminal and type the following command to generate a KeyStore.

keytool -genkey -alias test.foo.com -keyalg RSA -keystore foo.jks -keysize 2048

Specify a preferred KeyStore password when prompted.

Enter keystore password: <keystore_password>
Re-enter new password: <keystore_password>

Enter the first name and last name as *.foo.com and fill out the other information accordingly when prompted.

Example

What is your first and last name?
  [Unknown]:  <new_host_name>
What is the name of your organizational unit?
  [Unknown]:  
What is the name of your organization?
  [Unknown]:  WSO2
What is the name of your City or Locality?
  [Unknown]:  Mountain View
What is the name of your State or Province?
  [Unknown]:  CA
What is the two-letter country code for this unit?
  [Unknown]:  US
Is CN=*.foo.com, OU=Unknown, O=WSO2, L=Mountain View, ST=CA, C=US correct?
  [no]:  yes

Specify a preferred private Key password when prompted.
```
Enter key password for <keystore_password>
    (RETURN if same as keystore password):  <key_password>
Re-enter new password: <key_password>
```
- <key_password> - Enter the key password that you provided in step 1.2.
This will generate a KeyStore with a private key and a public certificate with CN as *.foo.com

Step 2 - Configure the SSL KeyStore

Follow the instructions to configure the WSO2 product with the generated KeyStore:

Copy the generated self-signed keystore, namely foo.jks, which was created in step 1, into the <PRODUCT_HOME>/repository/resources/security directory.
Export the public certificate from the keystore and import that certificate to the client-truststore.jks file.
1. Navigate to the <API-M_HOME>/repository/resources/security directory.
2. Export the public certificate from the primary KeyStore.
```
keytool -export -alias test.foo.com -file test.foo.com -keystore foo.jks -storepass <KEYSTORE_PASSWORD_GIVEN_ABOVE>
```
3. Import the certificate to the client-truststore.jks file.
```
keytool -import -alias test.foo.com -file test.foo.com -keystore client-truststore.jks -storepass wso2carbon
```

Step 3 - Update the KeyStoreFile and KeyStorePass parameters of the Tomcat HTTPS connector

Change the keystoreFile and keystorePass parameter of the Server.Service.Connector configuration with regard to port 9443 in the <API-M_HOME>/repository/conf/tomcat/catalinaserver.xml file as follows, in order to locate the new SSL KeyStore.

<Connector protocol=”org.apache.coyote.http11.Http11NioProtocol”
 port=”9443"
 bindOnInit=”false”
 sslProtocol=”TLS”
 sslEnabledProtocols=”TLSv1,TLSv1.1,TLSv1.2"
 maxHttpHeaderSize=”8192"
 acceptorThreadCount=”2"
 maxThreads=”250"
 minSpareThreads=”50"
 disableUploadTimeout=”false”
 enableLookups=”false”
 connectionUploadTimeout=”120000"
 maxKeepAliveRequests=”200"
 acceptCount=”200"
 server=”WSO2 Carbon Server”
 clientAuth=”false”
 compression=”on”
 scheme=”https”
 secure=”true”
 SSLEnabled=”true”
 compressionMinSize=”2048"
 noCompressionUserAgents=”gozilla, traviata”
 compressableMimeType=”text/html,text/javascript,application/x- javascript,application/javascript,application/xml,text/css,application/xslt+xml,text/xsl,image/gif,image/jpg,image/jpeg”
 keystoreFile=”${carbon.home}/repository/resources/security/foo.jks”
 keystorePass=”<KEYSTORE_PASSWORD_GIVEN_ABOVE>”
 URIEncoding=”UTF-8"/>

Restart the server for the changes to be applicable.

Step 4 - Configure the new key store

Update the <Password>, <KeyAlias>, <KeyPassword> values under the <KeyStore> field in the <API-M_HOME>/repository/conf/carbon.xml file based on your new key store configuration.

<KeyStore>
            <!-- Keystore file location-->
            <Location>${carbon.home}/repository/resources/security/foo.jks</Location>
            <!-- Keystore type (JKS/PKCS12 etc.)-->
            <Type>JKS</Type>
            <!-- Keystore password-->
            <Password><KEYSTORE_PASSWORD></Password>
            <!-- Private Key alias-->
            <KeyAlias><NAME_OF_THE_ALIAS></KeyAlias>
            <!-- Private Key password-->
            <KeyPassword><KEY_PASSWORD></KeyPassword>
        </KeyStore>

How can I fix the javax.net.ssl.SSLException: Received fatal alert: unknown_ca error that I get when invoking the methods of an API via the API Console?

The root cause of this issue is because the default pack is not shipped with a CA-signed certificate. When using the API Console, the web browser sends an HTTPs request to the API Gateway. As the certificate on the Gateway is not CA-signed, the browser does not accept it.

To resolve this issue, first access the Gateway URL via a new browser tab of the same browser and accept the certificate from the browser.

I hit the `DentityExpansionLimit` and it gives an error as {org.wso2.carbon.apimgt.hostobjects.APIStoreHostObject} - Error while getting Recently Added APIs Information. What is the cause of this?

This error occurs in JDK 1.7.0_45 and is fixed in JDK 1.7.0_51 onwards. See here for details of the bug.

In JDK 1.7.0_45, all XML readers share the same XMLSecurityManager and XMLLimitAnalyzer. When the total count of all readers hits the entity expansion limit, which is 64000 by default, the XMLLimitanalyzer's total counter is accumulated and the XMLInputFactory cannot create more readers. If you still want to use update 45 of the JDK, try restarting the server with a higher value assigned to the DentityExpansionLimit.

I get a `Hostname verfiication failed` exception when trying to send requests to a secured endpoint. What should I do?

Set the <parameter name="HostnameVerifier"> element to AllowAll in <APIM_HOME>/repository/conf/axis2/axis2.xml file's HTTPS transport sender configuration. For example, <parameter name="HostnameVerifier">AllowAll</parameter>.

This parameter verifies the hostname of the certificate of a server when the API Manager acts as a client and does outbound service calls.

When I add new users or roles, I get an error message as 'Entered user name is not conforming to policy'. What should I do?

This is because your user name or password length or any other parameter is not conforming to the RegEx configurations of the user store. See Managing Users and Roles.

When I call a REST API, I find that a lot of temporary files are created in my server and they are not cleared. This takes up a lot of space. What should I do?

There might be multiple configuration context objects created per each API invocation. Please check whether your client is creating a configuration context object per each API invocation. Also, configure a HouseKeeping task in the <APIM_HOME>/repository/conf/carbon.xml file to clear the temporary folders. For example.

<HouseKeeping> 
        <AutoStart>true</AutoStart> 
        
        <!-- The interval in *minutes*, between house-keeping runs --> 
        <Interval>10</Interval> 

        <!-- The maximum time in *minutes*, temp files are allowed to live in the system. Files/directories which were modified more than 
         "MaxTempFileLifetime" minutes ago will be removed by the house-keeping task --> 
        <MaxTempFileLifetime>30</MaxTempFileLifetime>
</HouseKeeping>

Why do I get the following error: Gateway Failures?

The Gateway Failures UI error occurs when the ServerURL, username, password and/or GatewayEndpoint is incorrect. This can be rectified by checking and correcting the latter mentioned gateway configurations under <Environments> in the <API-M>/repository/conf/api-manager.xml file.

If you are using the API-M instance, which you used as the first instance in this tutorial - Publish through Multiple API Gateways, to tryout other tutorials, you will face the above mentioned error, because you updated the environments configurations in that pack by adding two API Gateway environments under the <Environments> element, and commenting the <environment> element that comes by default. To overcome this error in the latter mentioned API-M pack, simply, uncomment the default configuration and delete the newly added configuration under <Environments> in the <API-M>/repository/conf/api-manager.xml file.

How can I capture the state of a system?

You can use the tool named Carbon Dump. At the time of an error you can use Carbon Dump (carbondump.sh) to collect all the necessary data (i.e., heap and thread dumps) from a running WSO2 API Manager instance in order to carryout a head dump and thread stack analysis. For more information on using this tool, see Capturing the state of the system in the Administration guide.

General questions

Can I implement an API facade with the API Manager?

You can use the API Manager and WSO2 ESB to implement an API facade architecture pattern. WSO2 recommends this architecture if you are performing heavy mediation in your setup. For implementation details of an API facade, see implementing an API facade with WSO2 API management platform.

As the API Manager does not have the ESB's GUI to perform mediation functions, you need to use the XML-based source view for configuration. Alternatively, you can create the necessary mediation sequences using the GUI of the ESB, and copy them from the ESB to the API Manager.

In addition, see the following use cases in WSO2 ESB documentation for more information on REST to SOAP conversion.

How can I write automated test scripts for the API Manager?

Use WSO2 Test Automation Framework (TAF) as explained in Writing a Test Case for API Manager.

Does WSO2 API-M support HTTP pipelining?

No, currently WSO2 API-M does not support HTTP pipelining.

FAQ