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. For more information, 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. For more details, see WSO2 Support.

What are the default ports opened in the API Manager?

For a list of all default ports available, 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. For more details, see API Manager components.

Can I get involved in API-M development activities?

Not only are you allowed, but also encouraged. You can start by subscribing to the 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 community page.

What is the default communication protocol of the API Manager?

The default communication protocol is Thrift.

Does WSO2 API-M support HTTP pipelining?

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

Installation and start up

What are the minimum requirements needed to run WSO2 API Manager?

For a list of system requirements, environment compatibility and required applications, see Installation Prerequisites.

Which MySQL database script should I use?

From Carbon kernel 4.4.6 onward, your product is shipped with two scripts for MySQL (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.

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 <API-M_HOME>/repository/components/lib directory and restart the server.

Can I connect the API Manager directly to an LDAP or Active Directory where corporate identities are stored?

Yes, you can configure the API Manager with multiple user stores. For more details, 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 stored in the <API-M_HOME>/bin/wso2server.sh file.  

How do I start up only selected components of the API Manager?

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. For more information, see Product Profiles.

Deployment

What are the 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.

Is it recommended to run 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 only accepts 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 Configuring the Proxy Server and the Load Balancer.

Functionality

Why can't I see all the APIs that I published on the API Store?

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 the <API-M_HOME>/repository/conf/api-manager.xml file.

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

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

Why are the changes I did to the  Response Content Type  resource parameter of a published API not reflected in the API Store, even 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 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 1.8.*, 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>

How can I extend the default API Manager server by installing new features?

See Working with Features in the WSO2 Admin Guide.

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

Set the javax.xml.stream.isCoalescing property to false in the <API-M_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 to the API Store? I want to engage my own approval mechanism.

To disable the self signup capability, open the API-M management console and click the Resources > Browse menu. The registry opens. Navigate to the /_system/governance/apimgt/applicationdata/sign-up-config.xml file and set the  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 the User Management category) to the API Manager and configure it. For more information, see User Account Locking and Account Disabling in the Identity Server documentation. For more information on installing features, see Working with features in the Admin Guide.

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 the <API-M_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 the /_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 the <API-M_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 authentication headers to messages going out of the API Gateway to the backend?

Uncomment the <RemoveOAuthHeadersFromOutMessage> element in the <API-M_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 can I protect my product server from security attacks caused by weak ciphers?

You can protect your server from attacks such as the Logjam attack (Man-in-the-Middle attack) by disabling weak ciphers. For more details, see Disable weak ciphers in the WSO2 Admin Guide.

Troubleshooting

Why do I get an illegal access attempt error while trying to authenticate APIKeyValidationService?

If you get the following error: org.wso2.carbon.server.admin.module.handler.AuthenticationHandler - Illegal access attempt, it may be due to the following reasons,

• Did you change the default admin password?
  If so, you need to change the credentials stored in the <APIKeyValidator> element of the <API-M_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 a mismatching certificate hostname 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 exception occurs is because the self-signed certificate that is shipped with WSO2 products is configured using the hostname as localhost, and 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:

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

1. 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

2. Specify a preferred KeyStore password when prompted.

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

3. 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

4. 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 generates 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:

1. Copy the generated self-signed keystore, foo.jks, which was created in step 1, into the <PRODUCT_HOME>/repository/resources/security directory.
2. 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

1. 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"/>

2. 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 a fatal alert: unknown_ca error when invoking the methods of an API via the API Console?

The root cause for the javax.net.ssl.SSLException: Received fatal alert: unknown_ca  error 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 get a Hostname verification failed exception when trying to send requests to a secured endpoint. What should I do?

Set the <parameter name="HostnameVerifier"> element to AllowAll in <API-M_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 stating that the 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, a lot of temporary files are created in my server and takes up a lot of space. What should I do?

There might be multiple configuration context objects created per API invocation. Check whether your client creates a configuration context object per API invocation. You can also configure a HouseKeeping task in the <API-M_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 a Gateway Failures error?

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 gateway configurations under <Environments> in the <API-M>/repository/conf/api-manager.xml file. 

Why does a timeout occur between the client and WSO2API-M connection before API Manager sends the response to the client?

The following are two possible reasons behind this timeout.

• The backend not being available.
• The backend may be slow

There are two socket timeouts, connection timeout and read timeout.

The connection timeout is the timeout in making the initial connection (i.e., completing the TCP connection handshake). The read timeout is the timeout on waiting to read the data. A read timeout error occurs if the server fails to send a byte seconds after the last byte.

The http.connection.timeout and http.socket.timeout are two different configurations that are defined in the <API-M_HOME>/repository/conf/passthru-http.properties file to handle the connection timeout and read timeout for sockets respectively.

http.connection.timeout defines a max time period to establish a connection with the remote host, and the http.socket.timeout defines the time waiting period for data after establishing the connection, which relates to the maximum time of inactivity between two data packets.

Therefore, you can maintain a high value for the http.socket.timeout parameter to avoid a connection read timeout related error. Thereby, you can increase the endpoint timeout value accordingly.

Example:
By default the socket timeout value (the socket timeout for the HTTP listener) is 60 seconds. If you observe a socket timeout error in your error logs, it means that the backend is taking longer than 60 seconds to respond.

Therefore, you can increase the socket timeout of the passthrough HTTP transport in the <API-M_HOME>/repository/conf/passthru-http.properties file to 120 seconds (http.socket.timeout=120000).

Usually, you would not need a high value for the HTTP connection timeout (http.connection.timeout), because it is expected to establish a connection with a server within 10 to 20 seconds. However, if it takes longer, you need to work on scaling the backend as it can not handle the current load that you are expecting.

How can I capture the state of a system?

At the time of an error, you can use a tool called 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.

How can I clean up the REG_LOG table?

The REG_LOG table contains all the registry operations performed for all the registry resources in the system. When you clean up this table, you need to keep the latest record from every resource path to maintain at least one resource reference in case of reindexing. Execute the following query to clean this table.

CREATE TABLE reg_log_ids_to_KEEP (
             REG_LOG_ID INTEGER,
             REG_TENANT_ID INTEGER
);

INSERT INTO reg_log_ids_to_KEEP (REG_LOG_ID, REG_TENANT_ID) 
SELECT MAX(REG_LOG_ID) AS REG_LOG_ID, REG_TENANT_ID FROM REG_LOG GROUP BY REG_PATH, REG_TENANT_ID;

DELETE FROM REG_LOG where REG_LOG_ID not in (SELECT REG_LOG_ID from reg_log_ids_to_KEEP);
drop table reg_log_ids_to_KEEP;

DELETE FROM REG_LOG WHERE REG_ACTION = 7;

Cleaning up the REG_LOG table periodically might be required if there is a large amount of data in the table, and as a result it takes a long time to process queries. Executing the query given above helps to improve the performance of the database.