NIFI-3765 - Added a 'status' operation to Node Manager

[YolandaMDavis]

The command for status is the following:

./node-manager.sh -d {nifi-installation-dir} -b {nifi-bootstrap-file} -o status [-u {url list}]

NodeManager will print any of the following messages based on the returned response or received exception:

When Site Returns Response Code == 200:
NiFi Node is running and available at {nifi-host-url}

When Site Returns Response Code != 200
Attempt to contact NiFi Node at {nifi-host-url} returned Response Code: {code} with reason {response body}

When exception occurs attempting to connect to the node
Attempt to contact NiFi Node at {nifi-host-url} did not complete due to exception {exception message}

If the -u parameter is used it will check the node hosts provided in the list. format for url list should be {http|https}://{node-host}:{node-port},...

e.g. -u "https://localhost-1:8080,https://localhost-2:8080"

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[mcgilman]

Will review...

[alopresto]

Reviewing...

[brosander]

Tested non-secure standalone instance, secure cluster. Works as expected.

[mcgilman]

Thanks @YolandaMDavis. Verified new capabilities and existing functions of the node-manager tool. This has been merged to master.