Docker: Update condition to enable tracing to avoid annoying warning messages

[VietND96]

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Description

Fixes #2355
Fixes #2415
Fixes #2423
Fixes #2432
Fixes #2481

By default, SE_ENABLE_TRACING is true to align with CLI option config https://www.selenium.dev/documentation/grid/configuration/cli_options/#logging
It is recommended that the user enable observability for tracing issues if having any. However, by default, it auto config the endpoint to a local OTLP localhost/[0:0:0:0:0:0:0:1]:4317 and raises the warning if endpoint is unreachable.

ERROR (ThrottlingLogger.dolog) Failed to export spans.
  The request could not be executed. Error message: Failed to connect to localhost/[0:0:0:0:0:0:0:1]:4117
  java.net.ConnectException: Failed to connect to localhost/[0:0:0:0:0:0:0:1]:4317 
at okhttp3.internal.connection.RealConnection.connectSocket(RealConnection.kt:297)
at okhttp3.internal.connection. ExchangeFinder.findConnection (Exchangefinder.kt: 226)
at okhttp3.internal.connection.okhttps.internal.connection.RealConnection.connect(RealConnection.kt:207)

This warning might annoy users or cause messed up logs to identify another real issue.

Instead of repetitively asking the user to add env var SE_ENABLE_TRACING=false, updating the condition to enable this feature should be SE_ENABLE_TRACING=true, and users have to input a correct endpoint to env var SE_OTEL_EXPORTER_ENDPOINT. Otherwise, it is disabled.

Motivation and Context

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist

• I have read the contributing document.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• All new and existing tests passed.

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PR Type

Enhancement

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Description

• Enhanced tracing configuration across all Selenium Grid components to prevent unnecessary warning messages
• Modified tracing condition to require both SE_ENABLE_TRACING=true and SE_OTEL_EXPORTER_ENDPOINT to be set
• Removed default SE_ENABLE_TRACING=false from all docker-compose files to simplify configuration
• Updated all component scripts (Hub, Node, Router, etc.) to use consistent tracing condition

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Changes walkthrough 📝

	Relevant files
Enhancement	start-selenium-grid-distributor.sh Update tracing condition in distributor script                      Distributor/start-selenium-grid-distributor.sh Updated tracing condition to require both SE_ENABLE_TRACING=true and SE_OTEL_EXPORTER_ENDPOINT to be set +1/-1      start-selenium-grid-hub.sh Update tracing condition in hub script                                      Hub/start-selenium-grid-hub.sh Modified tracing condition to check for both SE_ENABLE_TRACING and SE_OTEL_EXPORTER_ENDPOINT +1/-1
Configuration changes	docker-compose-v3.yml Remove tracing configuration from compose file                      docker-compose-v3.yml Removed SE_ENABLE_TRACING environment variable from all services +0/-5

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[qodo-merge-pro]

PR Reviewer Guide 🔍

Here are some key observations to aid the review process:

⏱️ Estimated effort to review: 2 🔵🔵⚪⚪⚪

🧪 No relevant tests

🔒 No security concerns identified

⚡ Recommended focus areas for review Validation Check The condition for enabling tracing requires both SE_ENABLE_TRACING=true and SE_OTEL_EXPORTER_ENDPOINT to be set. Verify that tracing is properly disabled when either condition is not met. if [ "${SE_ENABLE_TRACING}" = "true" ] && [ -n "${SE_OTEL_EXPORTER_ENDPOINT}" ]; then

[qodo-merge-pro]

PR Code Suggestions ✨

Explore these optional code suggestions:

Category	Suggestion	Score
General	Improve error handling by providing clear feedback when configuration is incomplete Add error message when tracing is enabled but endpoint is missing, to help users understand why tracing isn't working. EventBus/start-selenium-grid-eventbus.sh [84] -if [ "${SE_ENABLE_TRACING}" = "true" ] && [ -n "${SE_OTEL_EXPORTER_ENDPOINT}" ]; then +if [ "${SE_ENABLE_TRACING}" = "true" ]; then + if [ -z "${SE_OTEL_EXPORTER_ENDPOINT}" ]; then + echo "Warning: Tracing enabled but SE_OTEL_EXPORTER_ENDPOINT not set. Tracing will be disabled." + else Apply this suggestion Suggestion importance[1-10]: 8 Why: Adding an error message when SE_OTEL_EXPORTER_ENDPOINT is missing would significantly improve user experience by providing clear feedback about why tracing is not working, helping with troubleshooting.	8
	Enhance variable existence check to handle special characters and edge cases in shell scripts Add quotes around the variable reference in the condition to handle cases where the variable might contain spaces or special characters. EventBus/start-selenium-grid-eventbus.sh [84] -if [ "${SE_ENABLE_TRACING}" = "true" ] && [ -n "${SE_OTEL_EXPORTER_ENDPOINT}" ]; then +if [ "${SE_ENABLE_TRACING}" = "true" ] && [ -n "${SE_OTEL_EXPORTER_ENDPOINT:+x}" ]; then Apply this suggestion Suggestion importance[1-10]: 3 Why: While the suggestion to use :+x parameter expansion is technically valid for robust shell scripting, the current -n check is sufficient for this use case since the variable is already properly quoted.	3