[Doc] add http proxy example (#207)

Co-authored-by: Karen Metts <[email protected]>

Author: kaisecheng

CHANGELOG.md

@@ -1,7 +1,10 @@
+## 7.2.12
+  - [DOC] Add `http_proxy` environment variable for GeoIP service endpoint. The feature is included in 8.1.0, and was back-ported to 7.17.2 [#207](https://github.com/logstash-plugins/logstash-filter-geoip/pull/207) 
+
 ## 7.2.11
- - Improved compatibility with the Elastic Common Schema [#206](https://github.com/logstash-plugins/logstash-filter-geoip/pull/206)
-   - Added support for ECS's composite `region_iso_code` (`US-WA`), which _replaces_ the non-ECS `region_code` (`WA`) as a default field with City databases. To get the stand-alone `region_code` in ECS mode, you must include it in the `fields` directive. 
-   - [DOC] Improve ECS-related documentation
+  - Improved compatibility with the Elastic Common Schema [#206](https://github.com/logstash-plugins/logstash-filter-geoip/pull/206)
+    - Added support for ECS's composite `region_iso_code` (`US-WA`), which _replaces_ the non-ECS `region_code` (`WA`) as a default field with City databases. To get the stand-alone `region_code` in ECS mode, you must include it in the `fields` directive. 
+    - [DOC] Improve ECS-related documentation
 
 ## 7.2.10
   - [DOC] Air-gapped environment requires both ASN and City databases [#204](https://github.com/logstash-plugins/logstash-filter-geoip/pull/204)

docs/index.asciidoc

@@ -75,11 +75,15 @@ TIP: When possible, allow Logstash to access the internet to download databases
 [id="plugins-{type}s-{plugin}-manage_update"]
 ==== Manage your own database updates
 
-**Use a proxy endpoint**
+**Use an HTTP proxy**
 
 If you can't connect directly to the Elastic GeoIP endpoint, consider setting up
-a secure proxy. You can then specify the proxy endpoint URL in the
-`xpack.geoip.download.endpoint` setting in `logstash.yml` file.
+an HTTP proxy server. You can then specify the proxy with `http_proxy` environment variable.
+
+[source,sh]
+----
+export http_proxy="http://PROXY_IP:PROXY_PORT"
+----
 
 **Use a custom endpoint (air-gapped environments)**
 

logstash-filter-geoip.gemspec

@@ -1,7 +1,7 @@
 Gem::Specification.new do |s|
 
   s.name            = 'logstash-filter-geoip'
-  s.version         = '7.2.11'
+  s.version         = '7.2.12'
   s.licenses        = ['Apache License (2.0)']
   s.summary         = "Adds geographical information about an IP address"
   s.description     = "This gem is a Logstash plugin required to be installed on top of the Logstash core pipeline using $LS_HOME/bin/logstash-plugin install gemname. This gem is not a stand-alone program"