Google Maps API for both localhost & production server, as of April 2019 - google-maps

Question

TLDR
My code works fine on my laptop when accessed as file://<path>/index.html, but neither on my laptop with an Apache server running when accessed as http://<path>/index.html, nor on my real (production) server. I see no errors on the console, but the map is just a grey rectangle.
[Update] I moved to LeafletJS shortly after asking this question, and recommend others to do so too.
It has been a few years since I coded any Google Maps applications.
It seems that, as of last year, it is now necessary to have an API key, by providing it with credit card details, and to provide it with each API call.
Unfortunately, there is a lot of of information about this, much/most of it out of date and/or contradictory.
Can anyone point to the canonical guide, preferably with screenshots, of how to configure this?
I wish to draw a map, and add some makers, which will require reverse geocoding, such that I provide a street address and convert it to lat/long in order to place the markers.
Sounds simple enough, but which of the many thousands of "helpful" site has gotten it right?
For instance, what seems to be the current Google help page speaks of
From the Navigation menu, select APIs & Services > Credentials.
On the Credentials page, click Create credentials > API key
But I can't even see that menu option :-(
[Update] If it helps any, the error message in the developer console said :
Geocoding Service: You must use an API key to authenticate each request to Google Maps Platform APIs. For additional information, please refer to http://g.co/dev/maps-no-account For more information on authentication and Google Maps JavaScript API services please see: https://developers.google.com/maps/documentation/javascript/get-api-key
[Update] I am trying to access the API like this
<script src="maps.google.com/maps/api/…>
and
var url = 'https://maps.googleapis.com/maps/api/geocode/json?address=' + comapnyLocation +'&key=XXXX';
$http.get(url)
[Update++] in the developer console, I see a bunch of errors along the lines of:
aliextension.com/wp-content/uploads/2017/08/JAR.png:1 GET https://aliextension.com/wp-content/uploads/2017/08/JAR.png net::ERR_CONNECTION_TIMED_OUT
I have no idea what aliextension is, nor does it appear in my code (maybe in some minified JS?)
Ok, it is something to do with AliExpress (Ali Baba). I removed it & the timeout messages go away, but I still have problems.
If I load the index.html into Chrome as a file://, then it works just fine. But, if I load it `as http://, where I have a Xampp Apache server running, the map box remains grey, although I see no error messages. The same thing happens on my real server :-(

Answer 1

This page should be your starting point:
https://developers.google.com/maps/documentation/javascript/tutorial
it helps you working with Google map javascript API.
To embedded a google map to your website read the overview page in the above link.
To add markers to your google map read this page:
https://developers.google.com/maps/documentation/javascript/adding-a-google-map
To do reverse geocoding read this page:
https://developers.google.com/maps/documentation/javascript/geocoding
That all i need to work with google map. I think you can do the same too.

Answer 2

The cause for this is quite likely an API key restriction.
In order to permit these host-names or IP addresses, you have to:
a) go to the credentials panel and select the according project, then click on "Api key".
b) there you can loosen the restrictions, for HTTP referrers (for web-sites)
... or for IP addresses (in case these are server-side requests).