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client.geo.latitude

FLOAT, read-only.

Available inall subroutines.

Latitude, in units of degrees from the equator. Values range from -90 to +90 inclusive, with the exception of the special value 999.9 used to indicate absent data.

The latitude given is based on the WGS 84 coordinate reference system.

Example

An example showing construction of a geo URI as specified by RFC 5870 in VCL:

declare local var.geouri STRING;
set var.geouri = "geo:" + client.geo.latitude + "," + client.geo.longitude;

This produces a URI of the form geo:37.786971,-122.399677 (where WGS 84 is the default CRS).

Example

Here's an example showing classification to the five main Geographical zones in VCL (latitude values as of Oct 2018):

sub client_geo_zone STRING {
  declare local var.zone STRING;
  
  if (client.geo.latitude == 999.9) {
    set var.zone = "";
  } else if (client.geo.latitude >=  66.5) { # Arctic circle
    set var.zone = "North frigid";
  } else if (client.geo.latitude >=  23.5) { # Topic of Cancer
    set var.zone = "North temperate";
  } else if (client.geo.latitude <= -66.5) { # Antarctic Circle
    set var.zone = "South frigid";
  } else if (client.geo.latitude <= -23.5) { # Tropic of Capricorn
    set var.zone = "South temperate";
  } else {
    set var.zone = "Torrid";
  }


  return var.zone;
}

You can use VCL to convert to degrees, minutes and seconds:

declare local var.deg INTEGER;
declare local var.min INTEGER;
declare local var.sec FLOAT;


declare local var.angle FLOAT;
declare local var.whole FLOAT;
declare local var.frac FLOAT;


set var.angle = client.geo.latitude; # input
if (var.angle < 0.0) {
  set var.angle *= -1;
}


set var.frac = var.angle;
set var.whole = var.frac;
set var.frac %= 1.0;
set var.whole -= var.frac;
set var.deg = var.whole; # truncated, integer by rounding


set var.frac *= 60.0;
set var.whole = var.frac;
set var.frac %= 1.0;
set var.whole -= var.frac;
set var.min = var.whole; # truncated, integer by rounding


set var.sec = var.frac;
set var.sec *= 60.0; # floating seconds


log client.geo.latitude + " = " + var.deg "° " var.min "′ " var.sec "″ "
  + if (client.geo.latitude < 0.0, "S", "N");

For example, a latitude of 59.926 produces 59° 55′ 33.600″ N. The ′ and ″ symbols are Unicode prime symbols, not quotes.

Try it out

client.geo.latitude is used in the following code examples. Examples apply VCL to real-world use cases and can be deployed as they are, or adapted for your own service. See the full list of code examples for more inspiration.

Click RUN on a sample below to provision a Fastly service, execute the code on Fastly, and see how the function behaves.

Tag requests with geolocation data

Add geolocation data about the client browser as extra headers in any requests from Fastly to your origin.

Geofence / block access to content by region

Group countries to cache content by custom regions or reject requests from some regions entirely.

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