chart: proactive to set browser args via container env var

[VietND96]

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Description

Change in Docker image

SE_BROWSER_ARGS_* Add arguments for launching browser

Instead of adding arguments via the browser options from language bindings, for example:

options = ChromeOptions()
options.add_argument('--incognito')
options.add_argument('--disable-dev-shm-usage')
driver = webdriver.Remote(options=options, command_executor="http://localhost:4444/wd/hub")

You also can proactive to force applying arguments directly from (node, standalone or node-docker) container environment variables. Define the environment variable with name starts with SE_BROWSER_ARGS_ and following by config key is up to you (ensure those are unique when you define multiple arguments). For example:

docker run -d -p 4444:4444 \
  -e SE_BROWSER_ARGS_INCOGNITO=--incognito \
  -e SE_BROWSER_ARGS_DISABLE_DSHM=--disable-dev-shm-usage \
  selenium/standalone-chrome:latest

List chromium command-line arguments for your reference.

Note: Currently, this is applicable for node browsers Chrome/Chromium, Edge.

Change in Helm chart

Configuration of shm size limit for browser nodes

By default, node browsers (Chrome/Chromium, Edge) leave the config key dshmVolumeSizeLimit as empty. It means the /dev/shm volume mount is disabled, and argument --disable-dev-shm-usage is passed to the browser via container environment variable (get motivation from this post). You can set another valid value to enable it back. For example:

chromeNode:
    dshmVolumeSizeLimit: "2Gi"
edgeNode:
    dshmVolumeSizeLimit: "2Gi"

For Firefox node, the default value is kept as 2Gi. You can override it via firefoxNode.dshmVolumeSizeLimit.

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, Documentation

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Description

• Added support for setting browser arguments via environment variables prefixed with SE_BROWSER_ARGS_ for Chrome, Chromium, and Edge.
• Updated Helm chart templates to conditionally configure dshm volume mounts and set SE_BROWSER_ARGS_DISABLE_DSHM if dshmVolumeSizeLimit is empty.
• Enhanced documentation to include instructions for using SE_BROWSER_ARGS_* environment variables and configuring dshmVolumeSizeLimit.
• Updated default memory limits for browser nodes in values.yaml.

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Changes walkthrough 📝

	Relevant files
Enhancement	_helpers.tpl Conditional Configuration for Browser Arguments and Volume Mounts charts/selenium-grid/templates/_helpers.tpl Added conditional logic to set SE_BROWSER_ARGS_DISABLE_DSHM environment variable. Modified volume mounts to conditionally include /dev/shm. Updated size limit configuration for dshm volume. +11/-1    wrap_chrome_binary Capture and Apply Browser Arguments from Environment Variables NodeChrome/wrap_chrome_binary Added logic to capture and apply environment variables starting with SE_BROWSER_ARGS_. Appended captured arguments to the Chrome binary execution command. +10/-1    wrap_chromium_binary Capture and Apply Browser Arguments from Environment Variables NodeChromium/wrap_chromium_binary Added logic to capture and apply environment variables starting with SE_BROWSER_ARGS_. Appended captured arguments to the Chromium binary execution command. +25/-1    wrap_edge_binary Capture and Apply Browser Arguments from Environment Variables NodeEdge/wrap_edge_binary Added logic to capture and apply environment variables starting with SE_BROWSER_ARGS_. Appended captured arguments to the Edge binary execution command. +10/-1    values.yaml Update Default Memory Limits and shm Size Configuration    charts/selenium-grid/values.yaml Updated default memory limits for Chrome, Firefox, and Edge nodes. Modified dshmVolumeSizeLimit to be empty by default for Chrome and Edge nodes. +9/-9
Documentation	README.md Document Browser Argument Environment Variables                    README.md Added documentation for SE_BROWSER_ARGS_* environment variables. Provided examples and references for browser arguments. +25/-0    README.md Document Configuration of shm Size Limit for Browser Nodes charts/selenium-grid/README.md Added documentation for configuring dshmVolumeSizeLimit for browser nodes. Provided examples for setting dshmVolumeSizeLimit. +16/-3

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[qodo-merge-pro]

PR Reviewer Guide 🔍

⏱️ Estimated effort to review: 3 🔵🔵🔵⚪⚪

🧪 No relevant tests

🔒 No security concerns identified

⚡ Key issues to review Conditional Logic The conditional logic for setting the SE_BROWSER_ARGS_DISABLE_DSHM environment variable based on .node.dshmVolumeSizeLimit being empty might not be intuitive. Consider adding comments or documentation in the Helm chart to explain why this condition leads to the disabling of shared memory usage, which is a critical aspect for browser stability in container environments. Environment Variable Parsing The script captures and parses environment variables prefixed with SE_BROWSER_ARGS_ to construct browser arguments. Ensure that this approach is secure and robust against potential issues such as environment variable injection or improper handling of special characters in arguments. Script Robustness Similar to the Chrome wrapper, this script also processes SE_BROWSER_ARGS_ prefixed environment variables. It's crucial to validate the robustness and security of this parsing logic, especially in a production environment where incorrect handling can lead to command execution vulnerabilities.

[qodo-merge-pro]

PR Code Suggestions ✨

Category	Suggestion	Score
Possible bug	Ensure correct handling of environment variables containing spaces To avoid potential issues with spaces in the values of environment variables, wrap the value variable in quotes when appending it to SE_BROWSER_ARGS. This ensures that all arguments are correctly passed to the executable even if they contain spaces. NodeChrome/wrap_chrome_binary [30] -SE_BROWSER_ARGS="$SE_BROWSER_ARGS $value" +SE_BROWSER_ARGS="$SE_BROWSER_ARGS '$value'" Apply this suggestion Suggestion importance[1-10]: 9 Why: Wrapping the value variable in quotes ensures that environment variables containing spaces are correctly handled, preventing potential issues when passing arguments to the executable.	9
Enhancement	Improve the condition check for setting the SE_BROWSER_ARGS_DISABLE_DSHM environment variable To ensure that the environment variable SE_BROWSER_ARGS_DISABLE_DSHM is only set when dshmVolumeSizeLimit is explicitly empty, consider using a more explicit check for an empty string rather than using the empty function. This avoids potential issues where dshmVolumeSizeLimit might be set to a value that is considered empty by Helm but is not actually an empty string. charts/selenium-grid/templates/_helpers.tpl [253-255] -{{- if empty .node.dshmVolumeSizeLimit }} +{{- if eq .node.dshmVolumeSizeLimit "" }} - name: SE_BROWSER_ARGS_DISABLE_DSHM value: "--disable-dev-shm-usage" {{- end }} Apply this suggestion Suggestion importance[1-10]: 8 Why: The suggestion improves the robustness of the condition check by explicitly checking for an empty string, which avoids potential issues where dshmVolumeSizeLimit might be set to a value considered empty by Helm but is not actually an empty string.	8
Maintainability	Add error handling to the mapfile command to enhance script robustness To improve the robustness of the script, add error handling for the mapfile command to ensure that the script continues to function correctly even if the grep command fails to find any matches. NodeChromium/wrap_chromium_binary [25] -mapfile -t BROWSER_ARGS_ARRAY < <(printenv | grep ^SE_BROWSER_ARGS_) +mapfile -t BROWSER_ARGS_ARRAY < <(printenv | grep ^SE_BROWSER_ARGS_ || echo "") Apply this suggestion Suggestion importance[1-10]: 7 Why: Adding error handling for the mapfile command ensures that the script continues to function correctly even if the grep command fails to find any matches, improving the script's robustness.	7