fix(zipkin) include connect time in balancer span

CHANGELOG.md

@@ -64,8 +64,6 @@
 
 ## Unreleased
 
-### Fixes
-
 ### Breaking Changes
 
 - Blue-green deployment from Kong earlier than `2.1.0` is not supported, upgrade to
@@ -278,17 +276,20 @@ a restart (e.g., upon a plugin server crash).
 #### Plugins
 
 - **ACME**: `auth_method` default value is set to `token`
-[#8565](https://github.com/Kong/kong/pull/8565)
+  [#8565](https://github.com/Kong/kong/pull/8565)
 - **serverless-functions**: Removed deprecated `config.functions` from schema
-[#8559](https://github.com/Kong/kong/pull/8559)
+  [#8559](https://github.com/Kong/kong/pull/8559)
 - **syslog**: `conf.facility` default value is now set to `user`
-[#8564](https://github.com/Kong/kong/pull/8564)
+  [#8564](https://github.com/Kong/kong/pull/8564)
 - **AWS-Lambda**: Removed `proxy_scheme` field from schema
-[#8566](https://github.com/Kong/kong/pull/8566)
+  [#8566](https://github.com/Kong/kong/pull/8566)
 - **hmac-auth**: Removed deprecated signature format using `ngx.var.uri`
-[#8558](https://github.com/Kong/kong/pull/8558)
+  [#8558](https://github.com/Kong/kong/pull/8558)
 - Remove deprecated `blacklist`/`whitelist` config fields from bot-detection, ip-restriction and ACL plugins.
-[#8560](https://github.com/Kong/kong/pull/8560)
+  [#8560](https://github.com/Kong/kong/pull/8560)
+- **Zipkin**: Correct the balancer spans' duration to include the connection time
+  from Nginx to the upstream.
+  [#8848](https://github.com/Kong/kong/pull/8848)
 
 #### Clustering
 

kong/plugins/zipkin/handler.lua

@@ -4,8 +4,12 @@ local utils = require "kong.tools.utils"
 local propagation = require "kong.tracing.propagation"
 local request_tags = require "kong.plugins.zipkin.request_tags"
 local kong_meta = require "kong.meta"
+local ngx_re = require "ngx.re"
 
 
+local ngx = ngx
+local ngx_var = ngx.var
+local split = ngx_re.split
 local subsystem = ngx.config.subsystem
 local fmt = string.format
 local rand_bytes = utils.get_rand_bytes
@@ -331,6 +335,7 @@ function ZipkinLogHandler:log(conf) -- luacheck: ignore 212
   local balancer_data = ngx_ctx.balancer_data
   if balancer_data then
     local balancer_tries = balancer_data.tries
+    local upstream_connect_time = split(ngx_var.upstream_connect_time, ", ", "jo")
     for i = 1, balancer_data.try_count do
       local try = balancer_tries[i]
       local name = fmt("%s (balancer try %d)", request_span.name, i)
@@ -348,7 +353,8 @@ function ZipkinLogHandler:log(conf) -- luacheck: ignore 212
       tag_with_service_and_route(span)
 
       if try.balancer_latency ~= nil then
-        span:finish((try.balancer_start + try.balancer_latency) * 1000)
+        local try_connect_time = (tonumber(upstream_connect_time[i]) or 0) * 1000 -- ms
+        span:finish((try.balancer_start + try.balancer_latency + try_connect_time) * 1000)
       else
         span:finish(now_mu)
       end