Calculation of statistics of downloads in Google Analytics

Continuing the topic of using the bundle Nginx + Lua decided to share a small instruction on how to calculate the load of static data and taking all this into account in Google Analytics.

We assume that the nginx-lua bundle is already configured and we have the name of the counter. If not, then the network has a lot of instructions, there are also ready assemblies ( openresty.org ).
For accounting, we need a script that will send data to GA. I didn’t want to write my own and in Github-a, an example was found: github.com/wstucco/ssga.lua This script has one track method, which takes the required parameter name of the counter, the host name and the path to be transferred can also be passed . After it is triggered, on the statistics panel in real time we will see our transmitted path.
There are two ways to consider loading:

• take into account the path of the downloaded file;
• consider through events.

The first option is convenient when there is no sense in dividing files into categories / groups, or when there is no way to do this, but you want to keep statistics. The second option is suitable for the case when there is a strict file structure, for example: section-category-type.
Consider both.

Simple track record

The easiest way, which does not require any special manipulation and preparation. Therefore, I will give only the final part of the nginx config.

resolver 8.8.8.8; access_by_lua ' local ssga = require( "ssga" ) ssga.track({ua = "UA-25XXXXXX-1") '; 

Reboot and admire run records in GA.
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Accounting through events

This method requires you to determine how we will qualify the downloaded files. In GA terms, we need to distinguish 3 entities: category, action, label. In his case, I used folder names for this, then the final URL of the uploaded file was: dl.domain.name/category/action/label/filename.ext
It was also necessary to teach the existing script to transfer this information to GA. After minor modifications, an extended version of the script was obtained ( github.com/fuCtor/ssga.lua ).
As a result, we have the following configuration:

 server { listen 80; server_name dl.domain.name; root /var/www/public; error_page 502 /502.html; location / { add_header Cache-Control public; expires max; resolver 8.8.8.8; access_by_lua ' opt = {} index = 0 for value in string.gmatch(ngx.var.uri ,"%w+") do opt [index] = value index = index + 1 end local ssga = require( "ssga" ) ssga.event({ua = "UA-25XXXXXX-1", domain = "dl.domain.name", category = opt[0], action = opt[1], label = opt[2], value = 1}) '; } } 

Save reboot. Now we can keep statistics on downloads in a convenient form, make various cuts.

Performance

We will check how quickly our counter will work, so we will execute HEAD requests, the body does not interest us.

 Concurrency Level: 30 Time taken for tests: 3.223 seconds Complete requests: 1000 Failed requests: 0 Write errors: 0 Total transferred: 348000 bytes HTML transferred: 0 bytes Requests per second: 310.26 [#/sec] (mean) Time per request: 96.694 [ms] (mean) Time per request: 3.223 [ms] (mean, across all concurrent requests) Transfer rate: 105.44 [Kbytes/sec] received Connection Times (ms) min mean[+/-sd] median max Connect: 0 0 0.1 0 1 Processing: 94 95 0.6 95 99 Waiting: 94 95 0.6 95 99 Total: 94 95 0.6 95 99 

 Concurrency Level: 30 Time taken for tests: 0.048 seconds Complete requests: 200 Failed requests: 0 Write errors: 0 Total transferred: 69600 bytes HTML transferred: 0 bytes Requests per second: 4166.58 [#/sec] (mean) Time per request: 7.200 [ms] (mean) Time per request: 0.240 [ms] (mean, across all concurrent requests) Transfer rate: 1415.99 [Kbytes/sec] received Connection Times (ms) min mean[+/-sd] median max Connect: 0 0 0.3 0 1 Processing: 6 6 0.8 6 9 Waiting: 6 6 0.8 6 9 Total: 6 7 0.9 6 10 

The image in the cap is taken from here .