Allow Expression Language for "Trusted Hostname" attribute in the InvokeHTTP processor

To whom it may concern,
I have the following issue: I use Nifi to retrieve some values from different REST endpoints (HTTPS).

Well, in order to have something easily configurable, I have placed the URL of each REST Service I need to access in a configuration file (one file per endpoint). When it comes to configure the InvokeHTTPProcessor there is no way to have the TrustedHostname varying depending on the configuration file as I cannot use expression language.

In such a way I should need to duplicate the InvokeHTTP processor for a number of times that is equal to all the endpoints from which I would need to retrieve data from (as in the following example):

endpoint 1 ----------------- IP of URL1 ---------------- 1st InvokeHttp - TrsustedHostname for IP of URL1
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endpoint N ----------------- IP of URLN ---------------- Nth InvokeHttp - TrsustedHostname for IP of URLN

I would rather have only one single InvokeHTTP processor istantiated:
endpoint 1 ----------------- IP of URL1 ---------------- InvokeHttp - TrustedHostname = ${property}
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....................................................................................................
endpoint N ----------------- IP of URLN ---------------- InvokeHttp - TrustedHostname = ${property}

Hope I have been clear,

Regards,

Massimiliano