Generalise port implementation for IP comms in addition to serial

[wolffshots]

This is in preparation for being able to run the app on a separate device to the one that actually communicates with the inverter.
The goal is to be able to run this project on my main server with a more beefy system and higher reliability than a Raspberry Pi (which is how it is currently deployed) and replace the Pi with an ESP board running esphome-stream-server powered by the serial port directly rather than having to externally power the Pi.

Long term goal is to Dockerise the project (#59) and then I can work on improving efficiency further and implementing more robust healthchecks which can restart the project properly. Currently it just dispatches a command to restart the systemd service when certain issues are encountered.

[codacy-production]

Coverage summary from Codacy

See diff coverage on Codacy

Coverage variation	Diff coverage
Report missing for 959d4501	✅ 31.10%

Coverage variation details

	Coverable lines	Covered lines	Coverage
Common ancestor commit (959d450)	Report Missing	Report Missing	Report Missing
Head commit (1b0826e)	1051	683	64.99%

Coverage variation is the difference between the coverage for the head and common ancestor commits of the pull request branch: <coverage of head commit> - <coverage of common ancestor commit>

Diff coverage details

	Coverable lines	Covered lines	Diff coverage
Pull request (#60)	328	102	31.10%

Diff coverage is the percentage of lines that are covered by tests out of the coverable lines that the pull request added or modified: <covered lines added or modified>/<coverable lines added or modified> * 100%

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Footnotes

1. Codacy didn't receive coverage data for the commit, or there was an error processing the received data. Check your integration for errors and validate that your coverage setup is correct. ↩

[codecov]

Codecov Report

❌ Patch coverage is 34.53237% with 182 lines in your changes missing coverage. Please review.
✅ Project coverage is 66.49%. Comparing base (959d450) to head (1b0826e).
⚠️ Report is 7 commits behind head on main.

Files with missing lines	Patch %	Lines
diagnostics/diagnostics.go	0.00%	97 Missing ⚠️
main.go	10.90%	48 Missing and 1 partial ⚠️
ip/ip.go	48.83%	20 Missing and 2 partials ⚠️
serial/serial.go	85.71%	4 Missing and 2 partials ⚠️
mqtt/mqtt.go	28.57%	4 Missing and 1 partial ⚠️
api/api.go	25.00%	3 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##             main      #60       +/-   ##
===========================================
- Coverage   79.26%   66.49%   -12.77%     
===========================================
  Files          10       12        +2     
  Lines         786      982      +196     
===========================================
+ Hits          623      653       +30     
- Misses        152      310      +158     
- Partials       11       19        +8     

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[Copilot]

Pull Request Overview

This PR generalizes the port implementation to support both serial and IP communications in preparation for running the app on a separate device from the one communicating with the inverter. The changes introduce a common interface for communication ports and add support for IP-based connections while maintaining backward compatibility with serial communication.

• Introduced a common comms.Port interface to abstract communication methods
• Added IP communication support alongside existing serial communication
• Refactored code to use the new abstracted port interface throughout the application

Reviewed Changes

Copilot reviewed 33 out of 38 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
comms/comms.go	Defines the common Port interface and connection types for both serial and IP communications
ip/ip.go	Implements IP-based communication port with TCP socket connection
serial/serial.go	Refactored to implement the common Port interface while maintaining serial-specific functionality
main.go	Updated configuration parsing and connection setup to support both serial and IP connection types
messages/*.go	Updated to use the common Port interface instead of serial-specific types
config.json.example	Updated configuration structure to support both connection types
diagnostics/diagnostics.go	Added new diagnostics system for error tracking and health monitoring

---

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[Copilot]

The Read function has an infinite loop with no timeout handling. If no carriage return is received, the function will loop forever despite setting a read deadline. Consider adding a check for timeout errors or implementing proper timeout handling.

[Copilot]

Error message inconsistency: This returns 'ip port is not open' while the Write method returns 'ip port is nil on write'. Consider using consistent error messages like 'ip port is nil on read' to match the pattern used in serial implementation.

Suggested change

	if ip.Conn == nil {
	return "", errors.New("ip port is not open")
	return "", errors.New("ip port is nil on read")

[Copilot]

[nitpick] Commented out debug logging should be removed or made configurable rather than left as commented code. Consider using a configuration flag to enable/disable debug logging.

[Copilot]

[nitpick] Inconsistent capitalization in log messages. 'Serial port' should be 'serial port' to match the style of 'IP port' or vice versa for consistency.

Suggested change

	log.Printf("Opening Serial port: %v\n", serialPort)
	log.Printf("Opening serial port: %v\n", serialPort)

[Copilot]

[nitpick] Inconsistent capitalization in log messages. 'Serial port' should be 'serial port' to match the style of 'IP port' or vice versa for consistency.