"Executing invalid Datadog script" errors with every request

[toadjaune]

Description

For every request, 2 error log lines are generated, like those :

2024/07/24 12:48:07 [error] 216792#216792: *120 Executing invalid Datadog script, client: 10.2.3.178, server: , request: "GET /health/ HTTP/1.1", host: "10.2.1.156"
2024/07/24 12:48:07 [error] 216792#216792: *120 Executing invalid Datadog script while logging request, client: 10.2.3.178, server: , request: "GET /health/ HTTP/1.1", host: "10.2.1.156"

Please note that despite the presence of those logs, the traces are correctly sent.

System info

• Operating system : Ubuntu 24.04 LTS
• Kernel : Linux <hostname> 6.8.0-1011-aws #12-Ubuntu SMP Fri Jun 21 18:30:21 UTC 2024 x86_64 x86_64 x86_64 GNU/Linux
• Nginx : nginx/1.24.0 (Ubuntu) / 1.24.0-2ubuntu7
• nginx-datadog : 1.2.1
• datadog agent version : Agent 7.55.1 - Commit: 8ec9dff - Serialization version: v5.0.119 - Go version: go1.21.11

Minimal reproducing configuration

• Start with a fresh ubuntu 24.04 system
• Install the datadog agent with the one-liner here
• apt install nginx
• Install the nginx-datadog module in /usr/lib/nginx/modules/
• Set the following in nginx.conf :

  
  load_module modules/ngx_http_datadog_module.so;

user www-data; worker_processes auto; pid /run/nginx.pid; error_log /var/log/nginx/error.log;

events { worker_connections 768; }

http { server { listen 80 default_server; listen [::]:80 default_server;

stub_status; # triggers the extraneous log lines
# return 204; # does not trigger the issue

} }

* `systemctl restart nginx`
* `curl -v localhost`
* See the error log lines in `/var/log/nginx/error.log`

I suspect that the reason why the `return` config line does not exhibit the bug is because of https://github.com/DataDog/nginx-datadog/issues/58 (they aren't traced and don't trigger this module's code)

[toadjaune]

After further testing, this seems to be a regression introduced by version 1.2.0 ; 1.1.0 does not exhibit the bug.

[skomp]

I guess this is the same issue. We receive these logs since upgrade to version 1.2.0 and 1.2.1, respectively.

2024/07/25 11:43:58 [error] 42#42: *141704 Executing invalid Datadog script while sending to client, client: 10.0.38.226, server: localhost, ...
2024/07/25 11:43:58 [error] 42#42: *141704 Condition expression for  directive at :0 evaluated to unexpected value "". Expected "on" or "off". Proceeding as if the value were "off". while sending to client

Tested on nginx 1.25.4 for 1.1.0 dd plugin, 1.26.0 for 1.1.0, 1.27.0 for dd plugin version 1.2.1.

[obukhov]

Observing same exact issue in version 1.2.0

[kneufeld-pbp]

It looks similar to my issue #94, which has been merged and will be part of the next release. In the meantime, we have built the module ourselves from the master branch, and it appears to work without issue in our pre-production environments.

[toadjaune]

Indeed it does. Sorry for the duplicate !