Recently WSO2 launched ESB version 5.0.0 Beta. In my first blog post about what has been changed in WSO2 ESB 5.0.0 I’ve explained what the new things are in this release. In this second part I will summarize the following:
- What has been changed?
- Compatible WSO2 product versions
- Fixed issues
- Known issues
What has changed
Deprecated features and functionalities
With the ESB management console we could override transport configuration at runtime. This can lead to server instability. This feature was deprecated in 4.8.0.
- Configuring Transports.
– Globally configuring transports for the ESB
Using the axis2.xml file on <PRODUCT_HOME>/repository/conf/axis2 directory. The elements <transportReceiver> and <transportSender> are used to configure transport receivers and senders respectively.
Transports to be loaded and activated during server startup.
Using the catalina-server.xml file: <PRODUCT_HOME>/repository/conf/tomcat/catalina-server.xml
– Configuring transports at the service level: Transports configured at the service level affect individual services and not all the services deployed in the ESB.
ESB 4.8.1 ESB 5.0.0
- Mediation libraries were replaced by connectors in 4.8.0.: Mediation Library was a mechanism to group Templates and automatically expose it as a self contained set of function modules.
Skeleton structure of a mediation library.
Execute functions of library using a template invoker.
- A connector is a collection of templates that define operations users can call from their ESB configurations to easily access specific logic for processing messages.Connectors that allow your message flows to connect to and interact with services such as Twitter and Salesforce. You can write your own connector.
- Working with Connectors
Connector Store (https://store.wso2.com:9448)
WSO2 Connector Store via the ESB Tooling Plug-In
Creating a CAR file including connectors
Create a Composite Application (C-App) project including the required artifacts.
- Working with Connectors via the Management Console
- Using a Connector
JIRA connector (in a sequence configuration)
JIRA connector’s getIssue operation and pass in the issue ID.
- Using connectors in Developer Studio
Initializes and establishes the connection to the service. (authentication information for connecting to Google Spreadsheets).
Removed features and functionalities
- To apply security to a proxy service, to enable throttling and caching only through Developer Studio or mediators.
Old version (WSO2 ESB 4.9.0)
New version (WSO2 ESB 5.0.0)
- Applying Security to a Proxy Service.
- Throttle Mediator – Can be used to restrict access to services:
- To avoid heavy loads that can cause performance issues in the system.
- To avoid certain user groups (i.e. IP addresses and domains).
Example – This indicates the maximum number of concurrent requests that can pass through Synapse on a single unit of time, and this value applies to all the IP addresses and domains.
The Throttle policy can be defined within the Throttlemediator configuration.
Throttle policy which is saved in the Registry
The mediation sequence that should be applied when a request is accepted.
The mediation sequence that should be applied when a request is rejected.
- Cache Mediator: When a message comes to the Cache mediator, it checks whether an equivalent message has been seen before based on message hashes.
If such a message has existed before, the Cache mediator executes the onCacheHit sequence (if specified)
Type of the cache mediator:
Finder: If this is selected, the mediator is used to search for the request hash of incoming messages.
Collector: If this is selected, the mediator is used to collect response messages in the cache.
The Cache mediator configured in the Out sequence caches the response to this message.
When a similar message is sent to the second time, the previous response will be directly fetched from the cache and sent to the requester. This happens because no onCacheHit sequence is defined.
- EHcache based implementation has been removed from ESB 4.9.0 due to distributed caching related issues. (http://www.ehcache.org)
- Hazelcast based caching implementation with ESB 4.9.0.
Compatible WSO2 product versions
If you have any questions or want to share your thoughts, contact us.