Response:
Array
(
    [headers] => Requests_Utility_CaseInsensitiveDictionary Object
        (
            [data:protected] => Array
                (
                    [server] => nginx
                    [date] => Sun, 21 Apr 2019 11:11:17 GMT
                    [content-type] => application/json; charset=utf-8
                    [x-frame-options] => Array
                        (
                            [0] => SAMEORIGIN
                            [1] => DENY
                        )

                    [x-xss-protection] => 1; mode=block
                    [x-content-type-options] => nosniff
                    [access-control-allow-origin] => *
                    [access-control-allow-methods] => POST, OPTIONS
                    [access-control-allow-headers] => X-Requested-With, X-Prototype-Version, Origin, Accept, Content-Type, X-CSRF-Token, X-Pushover-App, Authorization
                    [access-control-max-age] => 1728000
                    [x-limit-app-limit] => 7500
                    [x-limit-app-remaining] => 7500
                    [x-limit-app-reset] => 1556686800
                    [etag] => W/"921ff0608bf7cf04c949d64c3c3332b1"
                    [cache-control] => max-age=0, private, must-revalidate
                    [x-request-id] => f328e47f-a59b-47c2-88e5-8e36ff30b7cd
                    [x-runtime] => 0.016837
                    [strict-transport-security] => max-age=31536000
                )

        )

    [body] => {"info":"no active devices to send to","status":1,"request":"f328e47f-a59b-47c2-88e5-8e36ff30b7cd"}
    [response] => Array
        (
            [code] => 200
            [message] => OK
        )

    [cookies] => Array
        (
        )

    [filename] => 
    [http_response] => WP_HTTP_Requests_Response Object
        (
            [response:protected] => Requests_Response Object
                (
                    [body] => {"info":"no active devices to send to","status":1,"request":"f328e47f-a59b-47c2-88e5-8e36ff30b7cd"}
                    [raw] => HTTP/1.1 200 OK
Server: nginx
Date: Sun, 21 Apr 2019 11:11:17 GMT
Content-Type: application/json; charset=utf-8
Transfer-Encoding: chunked
Connection: close
X-Frame-Options: SAMEORIGIN
X-XSS-Protection: 1; mode=block
X-Content-Type-Options: nosniff
Access-Control-Allow-Origin: *
Access-Control-Allow-Methods: POST, OPTIONS
Access-Control-Allow-Headers: X-Requested-With, X-Prototype-Version, Origin, Accept, Content-Type, X-CSRF-Token, X-Pushover-App, Authorization
Access-Control-Max-Age: 1728000
X-Limit-App-Limit: 7500
X-Limit-App-Remaining: 7500
X-Limit-App-Reset: 1556686800
ETag: W/"921ff0608bf7cf04c949d64c3c3332b1"
Cache-Control: max-age=0, private, must-revalidate
X-Request-Id: f328e47f-a59b-47c2-88e5-8e36ff30b7cd
X-Runtime: 0.016837
X-Frame-Options: DENY
Strict-Transport-Security: max-age=31536000

{"info":"no active devices to send to","status":1,"request":"f328e47f-a59b-47c2-88e5-8e36ff30b7cd"}
                    [headers] => Requests_Response_Headers Object
                        (
                            [data:protected] => Array
                                (
                                    [server] => Array
                                        (
                                            [0] => nginx
                                        )

                                    [date] => Array
                                        (
                                            [0] => Sun, 21 Apr 2019 11:11:17 GMT
                                        )

                                    [content-type] => Array
                                        (
                                            [0] => application/json; charset=utf-8
                                        )

                                    [x-frame-options] => Array
                                        (
                                            [0] => SAMEORIGIN
                                            [1] => DENY
                                        )

                                    [x-xss-protection] => Array
                                        (
                                            [0] => 1; mode=block
                                        )

                                    [x-content-type-options] => Array
                                        (
                                            [0] => nosniff
                                        )

                                    [access-control-allow-origin] => Array
                                        (
                                            [0] => *
                                        )

                                    [access-control-allow-methods] => Array
                                        (
                                            [0] => POST, OPTIONS
                                        )

                                    [access-control-allow-headers] => Array
                                        (
                                            [0] => X-Requested-With, X-Prototype-Version, Origin, Accept, Content-Type, X-CSRF-Token, X-Pushover-App, Authorization
                                        )

                                    [access-control-max-age] => Array
                                        (
                                            [0] => 1728000
                                        )

                                    [x-limit-app-limit] => Array
                                        (
                                            [0] => 7500
                                        )

                                    [x-limit-app-remaining] => Array
                                        (
                                            [0] => 7500
                                        )

                                    [x-limit-app-reset] => Array
                                        (
                                            [0] => 1556686800
                                        )

                                    [etag] => Array
                                        (
                                            [0] => W/"921ff0608bf7cf04c949d64c3c3332b1"
                                        )

                                    [cache-control] => Array
                                        (
                                            [0] => max-age=0, private, must-revalidate
                                        )

                                    [x-request-id] => Array
                                        (
                                            [0] => f328e47f-a59b-47c2-88e5-8e36ff30b7cd
                                        )

                                    [x-runtime] => Array
                                        (
                                            [0] => 0.016837
                                        )

                                    [strict-transport-security] => Array
                                        (
                                            [0] => max-age=31536000
                                        )

                                )

                        )

                    [status_code] => 200
                    [protocol_version] => 1.1
                    [success] => 1
                    [redirects] => 0
                    [url] => https://api.pushover.net/1/messages.json
                    [history] => Array
                        (
                        )

                    [cookies] => Requests_Cookie_Jar Object
                        (
                            [cookies:protected] => Array
                                (
                                )

                        )

                )

            [filename:protected] => 
            [data] => 
            [headers] => 
            [status] => 
        )

)