During solution import from the Servoy Admin Page, modules with certain name patterns are handled in a special way. Modules whose names start with "before_import" are handled as pre-import hooks. Their onOpen event handlers are executed before the solution is actually imported. Similarly, modules whose names start with "after_import" are handled as post-import hooks. Their onOpen event handles are executed after the solution is actually imported.
If you have several modules that start with "before_import" or "after_import", they will be all handled in this way, but no handling order is guaranteed. It is recommended that you have at most one pre-import and at most one post-import hook in your exported solutions.
While the onOpen event handlers of pre-import and post-import hooks are being executed, any output printed with application.output will be redirected to the import log, which you can see in the Servoy Admin Page.
Suppose you have a solution called "import_sample_01", with two modules called "before_import_01" and "after_import_01". The "before_import_01" module has the following onOpen event handler:
{{function onBeforeImportSolutionOpen()
{
application.output("Method executed before solution import.");
}}}
The "after_import_01" module has the following onOpen event handler:
{{function onAfterImportSolutionOpen()
{
application.output("Method executed after solution import.");
}}}
If you export this solution together with its two modules, and then you import it throught the Servoy Admin Page, in the import log you should see the lines
{{info Executing pre-import hook module 'before_import_01'.
info Method executed before solution import.}}
before any message related to the actual solution import, and also you should see the lines
{{info Executing post-import hook module 'after_import_01'.
info Method executed after solution import.}}
after all messages related to the actual solution import.