Enhance RabbitMQ receiver to support full set of node-level metrics from /api/nodes

[VenuEmmadi]

Component(s)

receiver/rabbitmq

Is your feature request related to a problem? Please describe.

The current rabbitmqreceiver implementation supports only a limited set of RabbitMQ node metrics. To improve observability, we propose extending the receiver to parse and emit all available metrics from the /api/nodes endpoint. This includes:

• Memory metrics (e.g., mem_used, mem_limit, mem_alarm)
• Disk metrics (e.g., disk_free, disk_free_limit, disk_free_alarm)
• File descriptors (fd_used, fd_total, rates)
• Socket metrics (sockets_used, sockets_total, rates)
• Process usage (proc_used, proc_total, rates)
• Garbage collection stats (gc_num, gc_bytes_reclaimed)
• I/O stats (io_read_avg_time, io_write_avg_time, io_read_count, etc.)
• Context switches
• Runtime environment info (processors, uptime, run_queue, etc.)
• Cluster & node metadata (node_type, enabled_plugins, applications, partitions, etc.)

This enhancement will ensure more complete observability for RabbitMQ clusters when using OpenTelemetry.

Describe the solution you'd like

• Update the receiver to parse additional fields from the /api/nodes response.
• Emit new metrics with appropriate semantic conventions (name, unit, type, attributes).
• Group metrics logically under appropriate metric categories.
• Update documentation and add unit tests.

Describe alternatives you've considered

No response

Additional context

No response

[github-actions]

Pinging code owners:

• receiver/rabbitmq: @VenuEmmadi

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