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When an API is published, a file with its synapse configuration gets created on the API Gateway. If you inspect the This synapse configuration of an API, you will see has a set of handlers as shown in the following example:
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By default, the extension handler is listed at last in the handler chain, and therefore is executed at last. You can configure the API Gateway to execute extension handlers first. To do that, open <APIM_HOME>/repository/conf/api-manager.xml file, uncomment the <ExtensionHandlerPosition> element and provide the value top as follows:
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For more information on Handlers, see Architecture Components.
Allowing publisher to select
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predefined sequences
Publisher is allowed to select the predefined sequences, when he defines the API via publisher webappWhen an API is created using the API Publisher Web interface, you can select its sequences.
User can design all sequences using Dev Studio or any other tool, and store the sequence.xml file in the governance registry. We have introduced a new registry collection to store the sequences file. For sequences, create "customsequences" collection at apimgt governance registry location. The registry path will be like " /_system/governance/apimgt/customsequences".
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