Chandana Napagoda's Blog

There are many ways to secure a Service/API using different Authentication mechanisms. Mutual Certificate authentication(AKA: Client Certificate Authentication) is one of the ways to secure Service or API. Recently I was trying to integrate with an API which is secured using Mutual Certificate Authentication. In this scenario, the backend service team gave me their certificate-based on PKCS#12. When integrating this backend system with WSO2 Platform, we have to use 'Multi-HTTPS transport'. With this 'Multi-HTTPS transport', it will grant great flexibility to define different SSL profiles with separate trust stores and key stores for different IPs or hosts. This custom SSL profile can be implemented for Client to Synapse Runtime(Client --> ESB) or Synapse Runtime to Backend(ESB --> Backend). If it is Client to ESB, then you have to define custom SSL Profiles in the transportReceiver section. In my use-case, it was for ESB to Backend. So I had to add custom SSL prof

Smook Mediator available in WSO2 EI/ESB can be used to do various message transformations. For an example read CSV file and transform to XML . I had a requirement where I wanted to load a CSV file content into the database. So, my initial idea was to convert CSV content into XML, then use the XSLT mediator to generate a data service request. But it will be a costly operation with lots of resource consumption. Therefore, instead of generating a data service request via XSLT, I tried to use the options available in Smooks. Smooks provides FreeMaker based templating support that can be used to convert CSV to SOAP. Here, first I have created a sample input CSV file and expected Data Service sample request message. With this, it will be very easy to generate data mapping. Below are the examples of CSV and Data Service models Sample.csv: UserId,NameFirst,NameLast 1,Chandana,Napagoda 2,John,Tester SampleOut.xml :  <au:addUsers_batch_req xmlns:au="https://blo

As you know, Kerberos can be used to authenticate System or users reside on a none secured network. In my use case, I have Windows AD and MSSQL server and I have a couple of WSO2 Servers running on Linux systems. In my initial setup I have configured, WSO2 servers has to use SQL users. But instead of using SQL users, I prefer to use AD users. So I have started configuring Kerberos and faced a lot of troubles. If you are starting from scratch, I would recommend writing a Java class to connect MSSQL server using Kerberos. Then You can identify all small mistakes such as character case issues, typos, JDBC driver compatibility issues, etc.  Below are a few issues I have faced: 1) CASE is significant in krb5.conf file 2) I found that we need to use MSSQL JDBC 6.4 version in order to get new tickets. But if you are just planning use pre-generated tickets, you can use the older version as well. Here are the steps you need follow when configuring Kerberos with WSO2 Enterp

Think about an integration scenario, where you are getting a list of data from a service endpoint(Data 1) and you want to exclude or match this response against the data returned by another service endpoint(Data 2). In such a situation, first, you need to have a unique attribute in both data set to exclude or match elements. So in my use case, list of data and matching content is as below <CodeLists> <CodeList> <Id> O </Id> <Name> Open </Name> </CodeList> <CodeList> <Id> C </Id> <Name> Cancelled </Name> </CodeList> <CodeList> <Id> X </Id> <Name> Denied </Name> </CodeList> <CodeList> <Id> P </Id> <Name> Pending </Name> </CodeList> <CodeList> <Id> D </Id> <Name> Duplicate </Name>

If you want to perform date and time related opertions with XSLT 'date' or 'dateTime' values, you can use 'xs:yearMonthDuration' or 'xs:dayTimeDuration' function to achieve this. You can add or reduce years, months, date, hours or even minutes through those functions.  xs:yearMonthDuration For this function input value is year month duration and it should be passed in  ISO_8601 format n- the [n] is replaced by the value for each of the date and time elements P - The duration designator(for period). nY- the number of years. nM- the number of months. ex: xs:yearMonthDuration('P1Y2M') - 1 Year and 2 Months ex:  xs:yearMonthDuration('-P1Y2M')  - Negative 1 Year and 2 Months xs:dayTimeDuration For this function input value is day time duration and it also needs to be passed in  ISO_8601 format n- the [n] is replaced by the value for each of the date and time elements P - The duration designator(for period). nD- the

With WSO2 Enterprise Integrator or Enterprise Service Bus servers, if you want to change the backend server response code, you can set custom status status code as below:  <property name="HTTP_SC" scope="axis2" type="STRING" value="403"/> If you are getting 'HTTP/1.1 202 Accepted' response from your backend, you need to set "SC_ACCEPTED" as false by setting a custom SC_ACCEPTED Ex:  Receiving 202 from backend and change it to 200 <filter regex="202" source="$axis2:HTTP_SC">         <then>             <property action="remove" name="HTTP_SC" scope="axis2"/>             <property name="SC_ACCEPTED" scope="axis2" value="false"/>             <property name="HTTP_SC" scope="axis2" type="STRING" value="200"/>         </then>         <else/>