When a page for a request cannot be found, the portal will check if there are custom redirects configured, and if the URL that caused the _404 Not Found error has an entry in this map, the client will be redirected accordingly.
Whether those redirects will send a 301 Moved Permanently or a 303 See Other is controlled by the
redirects.custom.permanentRedirects setting.
Data about redirects can be loaded from Mesh by the RedirectHandler itself, or by the
DataProviderVerticle.
When the RedirectHandler should load the page containing redirects itself, the value of the
redirects.custom.source setting is the path to the page. The redirects.custom.reload setting controls whether
this page is loaded every time the RedirectHandler is activated (when set to true), or if the redirects are only
loaded once (when set to false).
To use data loaded by the DataProviderVerticle the value for redirects.custom.source must begin with
dataProvider: and after that a valid data key must be specified.
The page loaded either by the RedirectHandler or the DataProviderVerticle is a normal node from Mesh with the
[schemaPrefix]_content schema.[1]
The actual mapping from old URL to new URL will be extracted by an implementation of the RedirectHelper interface,
which convertData() method gets a JsonObject with the loaded Mesh node, is must return a mapping between URLs.
Which implementation is to be used, is configured by specifying the fully qualified class name of the implementation
in redirects.custom.helperClass.
When the RedirectHandler is initialized, the settings from redirects.custom.helperConfig will be passed to the
used RedirectHelpers init() method.
schemaPrefix being either the value of meshSchemaPrefix, or if that is not set the meshProjectName.