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To capture HTTP response headers from the REST plugin, simply create a user defined output for each header you want to save. All response headers from the HTTP request will be returned available to be used as plugin outputs, so they can be easily accessed.
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Next, define the plugin outputs that will store the headers in the workflow variables we just created. Open your REST plugin step in the workflow, then select the “User Output” tab. Here, specify the header name in the “Plugin Output” field, and the workflow variable you want to use in the “Workflow Variable” field. Only headers defined here will be available as plugin outputs.
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Now you can use the workflow variables in subsequent workflow steps.