DAL/Node: initial support for Opentelemetry

What

Rewrite !15821 (closed) using the PPX Profiler

Why

Allows tracing shards using Opentelemetry, and make the profiler opt-in thanks to the PPX.

How

• See !18340 (merged) for a prerequisite
• Manifest shenanigans to add the dependency
• To make traces consistent, derive trace ids from slot ids
• Trace publish and verifying shards

Manually testing the MR

The simplest way to test it is using the sandbox mode (adding jeager to tezt-cloud should be a follow-up):

1. Let's build the node with the instrumentation

TEZOS_PPX_PROFILER=opentelemetry make octez-dal-node

2. Start jeager, to witness the traces:

docker run --rm --name jaeger \
  -e COLLECTOR_ZIPKIN_HOST_PORT=:9411 \
  -p 16686:16686 \
  -p 4317:4317 \
  -p 4318:4318 \
  -p 14250:14250 \
  -p 14268:14268 \
  -p 14269:14269 \
  -p 9411:9411 \
  jaegertracing/all-in-one:1.63.0

3. Start the sandbox (thanks to the DAL extension):

In different shells:

./src/bin_node/octez-sandboxed-node.sh 1 --connections 1

eval `./src/bin_client/octez-init-sandboxed-client.sh 1`
octez-activate-alpha
PROFILING=Debug PROFILING_BACKENDS=opentelemetry ./src/bin_dal_node/octez-sandboxed-dal-node.sh 1 --producer 0

Now that you have the full setup, you can produce data (in another shell):

eval `./src/bin_client/octez-init-sandboxed-client.sh 1`
src/bin_client/publish_dal_slot.sh bootstrap1 1 abc
octez-client bake for --minimal-timestamp --dal-node http://localhost:$DAL_NODE_RPC_PORT --count 3

If everything went right, in Jaeger you should be able to witness the trace:

• Go to http://localhost:16686
• Select the DAL node in Service (you should see that it is identified by its peer id, to be able to discriminate between different nodes).
• Click on Find Traces

Then when clicking on the trace:

Checklist

• Document the interface of any function added or modified (see the coding guidelines)
• Document any change to the user interface, including configuration parameters (see node configuration)
• Provide automatic testing (see the testing guide).
• For new features and bug fixes, add an item in the appropriate changelog (docs/protocols/alpha.rst for the protocol and the environment, CHANGES.rst at the root of the repository for everything else).
• Select suitable reviewers using the Reviewers field below.
• Select as Assignee the next person who should take action on that MR