Line interpolation changes

[7Adrian]

This disscussion is connected to #60.

@tigerblue77 I’ve locally merged the code with the current state of the master branch, incorporating all changes from my pull request. I really like the improvements you’ve made—they align with many of my ideas, and they enhance the overall solution. Great work! 😃

Here are some additional suggestions that I think could further improve the code and its functionality:

1. functions.sh

• Use a parameterized method to set the fan speed and create a handler for it. This way, a single method handles setting the fan speed, while the handler interprets and processes the inputs (e.g., strings and fan speeds).
  This would make the fan speed-setting function essentially “untouchable” in the future, while the handler remains open for extensions, such as adding a PID control option.

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2. Dell_iDRAC_fan_controller.sh

• Add a feature at startup to display a chart illustrating the behavior of fan speed in response to temperature. This would look similar to the graph shown in the README (CPU temperature vs. fan speed).
• Move the interpolation and mathematical calculations to functions.sh or a new calculations.sh file. This could help clean up the main loop, making it easier to read and maintain. I’ll discuss main loop cleanup further below.

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3. tests.sh (Unit Tests)

• Add unit tests for the line interpolation calculations (as referenced in Add automated tests before generating a new Docker image to avoid pushing non-working code on master branch #79). These tests will ensure the interpolation logic remains accurate and reliable.

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4. Other Proposals

While not directly related to line interpolation, here are some additional ideas that could enhance the project:

• Main Loop Refactor: Break the main loop into smaller, dedicated functions, such as:
  apply_overheat, apply_fan_speed, apply_fan_interpolated_speed, print_temperatures, etc.
  This would improve code readability and modularity.

• Optimize Fan Speed Changes: Only overwrite the fan speed if the value changes. Although I haven’t measured the exact impact, it’s likely that establishing a connection and processing data via iDRAC could be slightly costly.

• Enhanced Console Output: Add color and styling to the console output using ANSI codes. This could improve visibility and make the output more user-friendly. However, keep in mind that this might require additional maintenance, and the printing-related code could become slightly harder to read.

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What are your thoughts on these changes? I’m happy to discuss further and collaborate on implementing them!

[tigerblue77]

Please marry me.

Joke aside...

@tigerblue77 I’ve locally merged the code with the current state of the master branch, incorporating all changes from my pull request. I really like the improvements you’ve made—they align with many of my ideas, and they enhance the overall solution. Great work! 😃

Thanks a lot, you made me happy.

Overall, they're good ideas. Some of them I've already had, and some others require thought and discussion. I'm currently working on my homelab to deploy a new Docker application (no link with this repository) and will get back to you later tonight or this week. Thanks for your work.

[7Adrian]

Update on Implementation

I've completed the first three points of the proposed changes. Here's a summary of what has been implemented:

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1. Handler for Applying Fan Speed

I’ve added a handler function for applying user-defined fan speed. This function supports both static and dynamic fan control and can handle decimal or hexadecimal inputs for fan speed. Below is the function implementation:

# Apply user-defined fan control settings
#
# This function applies user-defined fan control settings based on the specified mode and fan speed.
# It handles both decimal and hexadecimal fan speed inputs, converting between them as needed.
# The function then applies the fan control and updates the current fan control profile.
#
# Parameters:
#   $1 (MODE): The fan control mode.
#              1 for static fan speed, 2 for dynamic (interpolated) fan control.
#   $2 (LOCAL_FAN_SPEED): The desired fan speed. Can be in decimal (0-100) or hexadecimal (0x00-0x64) format.
#
function apply_user_fan_control() {
  local MODE=$1
  local LOCAL_FAN_SPEED=$2

2. Interpolation Welcome Chart

A table with calculated parameters based on the set values is displayed on startup:

The calculation of line interpolation has been moved to functions.sh and can be used by:

calculate_interpolated_fan_speed "$temp" "$lower_threshold" "$upper_threshold" "$min_speed" "$max_speed"

This method returns the calculated interpolated fan speed as a decimal percentage (0-100).

3. Unit Tests for Interpolation Calculation

Unit tests for the interpolation calculation have been added using the bats-core library. (I didn’t create additional files required by their license.)

To run tests, use:

./tests.sh

4. Next Steps

I think this part should be completed after merging the current changes and setting up CI/CD.