Migrating From StreamBase 6 to 7

Study the New and Noteworthy sections for earlier 7.x releases.

Studio 7.x includes a new EventFlow Editor with advanced features, as described in EventFlow Editor Differences. All EventFlow files open automatically in the new Editor if you start with a new, blank Studio workspace. If you open an existing 6.x workspace in Studio 7.x, EventFlow files might open in the Legacy EventFlow Editor instead. To prevent this, follow these steps:

The exception is that any EventFlow file you ever opened using the Open With context menu in Studio 6.x might still open in the Legacy EventFlow Editor in 7.x. In this case, close the Editor session and reopen it one time in Studio 7.x using the Open With → EventFlow Editor context menu. Thereafter, that file opens in the new Editor.

The 7.x series adds menu items, views, and editors to the standard StreamBase Studio perspectives. If you are re-using an existing Studio workspace, you must run reset your perspectives in order to see the new features. To reset perspectives, follow these steps:

StreamBase 7.x includes a newer version of the Logback libraries than the release 6.x series, and one section of Logback configuration files was updated to a new format. See Using StreamBase Logging for an overview of StreamBase logging.

If your 6.x projects include a Logback.xml file, migrate the affected section to the new format. In particular, the Logback configuration files appropriate for 6.x use the format shown in the following example for specifying a pattern layout for log messages:

<layout class="ch.qos.logback.classic.PatternLayout">
  <pattern>[LogBack %p] %c{0} - %m%n</pattern>
</layout>

This is replaced in the 7.x version with the <encoder><pattern> format shown in the following example:

<encoder>
  <pattern>[LogBack %level] %logger{0} - %msg%n</pattern>
</encoder>

Because of this format change, Logback configuration files that worked well with a 6.x release will continue to work with StreamBase 7.x, but at the cost of a dozen WARNING messages emitted that urge you to switch to the newer <encoder> format.

The StreamBase Server configuration file's XML syntax has several important changes described next and in the 7.0.0 New and Noteworthy. To take advantage of the new features, StreamBase Systems recommends opening your existing configuration files in Studio 7.x's Configuration File Editor. Add the new namespace declarations to the top <streambase-configuration> element, as described in Upgrading Configuration Files, then correct any typecheck errors detected. As an alternative, you can generate a new skeleton configuration file in Studio, or with sbd -s, then copy the custom settings from your old configuration files to the new file.

Server configuration file attributes documented as deprecated in previous releases were removed as of 7.0.0, and now cause a typecheck error if detected in your .sbconf files. These include:

The <runtime> element's <application> child element of the server configuration file is now deprecated in favor of the same elements in StreamBase deployment files. Your existing server configuration files are still supported, but StreamBase Systems strongly recommends migrating to deployment files.

In the StreamBase expression language, three functions were updated and no longer accept a string length argument. In any application that uses format(), systemproperty(), or systemenv(), adjust the expression to remove the extra argument.

As a consequence of release 7.x's high resolution profiling feature, the system stream on which StreamBase Server emits statistics was renamed to system.statv2 (from system.stat in previous releases).

As a result, any server monitoring utilities compiled with the 6.x Client Library (including StreamBase Manager, sbmonitor, and sbprofile from 6.x) fail to connect to StreamBase Server 7.x. You must use StreamBase Manager, sbmonitor, and sbprofile from 7.x to monitor or profile Server 7.x. Any custom monitoring utilities must be recompiled with the 7.x Client Library to be able to monitor Server 7.x.

Support was added to rename columns in SQL queries in Query operators associated with a JDBC Table data construct. For example, select column1 as field1 now works as expected to return a column named field1 in the results of the query. In previous releases, the AS keyword was accepted, but the returned field was not actually renamed.

In previous releases, when you added a new Aggregate operator to the EventFlow canvas, the grid in the Properties view's Aggregate Functions tab contained a single default entry with these values:

Starting with release 7.0.0, the default expression function is now lastval(*):

When you define or import a named schema, StreamBase automatically adds a function with the same name to the expression language that lets you construct an instance of that schema, as described in the named schema constructor function. In 6.x releases, named schema constructor functions were always called by argument position. In StreamSQL, you were required to include AS clauses to specify field names. In EventFlow modules, field names specified with AS clauses in expressions were accepted but ignored.

Starting with release 7.0.0, named schema constructor functions can now be called either by argument position or by field name. To call by field name, construct the tuple with AS clauses to specify the schema field name for function arguments, which sets values for only the specified fields in the resulting tuple. You do not need to specify all fields; any fields not represented in the arguments are automatically given a null value. As of 7.0.0, it is an error to mix AS-clause and non AS-clause arguments in the same named schema constructor.

There are two ways this change can result in typecheck errors when you open a 6.x application in 7.x:

Studio's EventFlow Editor underwent a major transformation as of StreamBase 7.0.0. The great majority of editing features work the same as before, but with new ease of use and editing efficiency. EventFlow application files from Studio 6.x open in Studio 7.x without requiring a conversion process. EventFlow modules are silently upgraded to take advantage of new features when you next save the module in 7.x.

Notice that the selection outlines around component icons are now automatically sized as wide as the component's name. Data constructs such as Query Tables are also automatically sized to the width of their assigned names. This may result in crowded or overlapping components in some modules that were last saved in StreamBase 6.x. You may prefer to rearrange components on the canvas before saving the first time. You can rearrange automatically by pressing Ctrl+L.

See EventFlow Editor 7.x Differences for a complete list of the differences between the 6.x and 7.x EventFlow Editors.

Using the new EventFlow Editor serializes new values for height, width, and coordinates of components on the EventFlow canvas. If you save an EventFlow module in Studio 7.x, then re-open it with an earlier release's Studio, the placement of components on the canvas may be affected.

As of 7.0.0, Studio is based on Eclipse 3.6, with compatibility for Eclipse 3.5 plug-ins. Studio now ships with the Subversive plug-in to provide support for the Subversion version control system.

Studio 7.x no longer includes a wizard to load and migrate Studio 3.x projects.

If you have custom server monitoring programs compiled with any 6.x release, you must recompile them with the 7.x Client Library to be able to monitor Server 7.x.

By contrast, existing enqueuing and dequeuing client programs compiled with the 6.x Client Library will continue to enqueue to or dequeue from Server 7.x. This is because StreamBase Server, as before, includes automatic proxying of the network protocol versions of previous releases.

However, StreamBase Systems recommends recompiling all 6.x client programs to take advantage of changes in the 7.x API.

The StreamBase Client Library for Java changed in the following ways for the classes listed. Existing code that uses deprecated methods will now have compile errors until adjusted to take into account these updates.

The StreamBase Client Library for C++ changed in the following ways: