Receiving Email Alerts


This application demonstrates how to send a single event via Single Simulation, and to generate alerts using filters when the threshold value is exceeded. Furthermore, it shows how to configure WSO2 Streaming Integrator Tooling to publish an alerts via e-mail. An alert is generated as an email when a high value transaction (i.e., where the value is over 5000) takes place.

Before you begin:

  • Enable access to less secure apps in the gmail account you are using for this example via the Less SecureApps link.
  • In the sample application, change the values for the following parameters in the @sink annotation as follows.
    • username -> business.rules.manager (This is the sender's username.)
    • password -> business-rules (This is the sender's password.)
    • address-> [email protected] (This is the sender's address.)
    • to -> [email protected] (This is the receiver's address.)
    • subject -> Alert for large value transaction: cardNo: (This is the subject of the email.)
      Once you update the values for the above parameters, save the sample Siddhib application.

Executing the Sample

To execute the sample open the saved Siddhi application in Streaming Integrator Tooling, and start it by clicking the Start button (shown below) or by clicking Run => Run.

Start button

If the Siddhi application starts successfully, the following message appears in the console.

AlertsAndThresholds.siddhi - Started Successfully!.

Testing the Sample

To test the sample Siddhi application, simulate a single event for it via the Streaming Integrator Tooling as follows:

  1. To open the Event Simulator, click the Event Simulator icon.

    Event Simulator Icon

    This opens the event simulation panel.

  2. To simulate events for the TransactionStream stream of the AlertsAndThresholds Siddhi application, enter information in the Single Simulation tab of the event simulation panel as follows.

    Select Siddhi Application and Stream

    Field Value
    Siddhi App Name AlertsAndThresholds
    StreamName TransactionStream

    As a result, the attributes of the Transactiontream stream appear as marked in the image above.

  3. Enter values for the attributes as follows:

    Enter Attribute Values

    Attribute Value
    creditCardNo 1234567898765432
    country SL
    item mobile
    quantity 100
    price 5000


    To generate an email alert, you need to simulate an event where the transaction value (i.e., quantity * price) exceeds 5000. This is indicated by the [quantity * price > 5000] filter connected to the TransactionStream input stream.

  4. Click Send.

Viewing the Results

To view the results, check the receiver gmail inbox (i.e., gmail specified via the to parameter in the sink configuration). The following is displayed.

Subject: Alert for large value transaction: cardNo:1234567898765432
Click here to view the sample Siddhi application.
@App:description('Simulate a single event and receive alerts as e-mail when a predefined threshold value is exceeded')

define stream TransactionStream(creditCardNo string, country string, item string, quantity int, price double);

      username ='business.rules.manager',
      address ='[email protected]',
      password= 'business-rules',
      subject='Alert for large value transaction: cardNo:',
      to='[email protected], [email protected]',
      port = '465',
      host = '',
      ssl.enable = 'true',
      auth = 'true',
define stream AlertStream(creditCardNo string, country string, item string, quantity int, price double);

--Filter events when quantity * price > 5000 condition is satisfied
from TransactionStream[quantity * price  > 5000]
select *
insert into AlertStream;