[DOCS] Add Docs for GitLab telemetry using the GitLab receiver

[Calm-Rock]

Scope of Task

We need documentation that explains how to use the GitLab Receiver to collect and send GitLab pipeline traces to SigNoz for both SigNoz Cloud and Self‑Hosted SigNoz.

The document should include:

• Configuring the GitLab Receiver as a webhook endpoint for pipeline and job events
• Setting up GitLab webhooks (project or group level)
• Routing telemetry data to SigNoz via the OpenTelemetry Collector
• Validating output on the SigNoz UI (traces view)

Note: This receiver currently supports traces only (in development phase) — see the GitLab Receiver README.

---

Tasks

1. Traces Documentation
   • Describe how to configure the webhook block in the GitLab Receiver (endpoint, path, health_path, secret, etc.).
   • Include steps to create a GitLab “Pipeline Hook” and “Job Hook” webhook, with required headers and secret.
   • Provide an OpenTelemetry Collector YAML snippet that routes GitLab webhook events into the collector and exports them to SigNoz.
   • Show example pipeline and job spans in the SigNoz UI (screenshots of the traces view).

---

Where Should the Docs Go?

• File Path: docs/cicd/gitlab.mdx
• Metadata ID: gitlab
• Title: GitLab Observability
• Sidebar Name: GitLab under a new top‑level section CICD

---

Resources

• GitLab Receiver README
• GitLab Webhooks Documentation
• GitLab receiver issue

[soumyajyotiii]

ACK. You can assign this to me.

[soumyajyotiii]

Should I add screenshots? I mean they are something that makes life a bit easy.
In that case would you guys be able to provide the Gitlab access? For Signoz I can spin up a standalone container.

[soumyajyotiii]

Just wanted to update on where I’m at with the GitLab Receiver:

• I’ve spun up a self-hosted SigNoz instance and built a custom OTEL Collector including the GitLab receiver.
• The collector’s health endpoint (GET /health) responds correctly, and I’ve successfully exposed it via ngrok to receive GitLab webhooks.
• However, any POST /events calls (including real pipeline and job payloads) still return HTTP 404, because the trace-generation handlers for /events aren’t implemented in the current GitLab receiver. Which is also mentioned in the README attaching the screenshot below

This is a hard blocker and we’ll need to wait for the upstream merge of full pipeline-to-trace support in the receiver.