hochfrequenz / mako_time_converter

Go Package to Convert German "Gastag" to regular "Tag" and Inclusive↔Exclusive End Dates

mako_time_converter (go)

This is a Go module to convert between German "Gastag" and "Stromtag", between inclusive and exclusive end dates and combinations of all them. This is relevant for German Marktkommunikation ("MaKo").

This is a Golang port of the mako_datetime_converter for .NET.

Rationale

The German Marktkommunikation ("MaKo") defines some rules regarding date times:

• you shall communicate end dates as exclusive (which is generally a good idea)
• you shall use UTC date times with a specified UTC offset (which is a good idea)
• and you shall always use UTC-offset 0 (a rule with good intentions)
• in electricity all days (and contracts) start and end at midnight of German local time
• but in gas all days (and contracts) start and end at 6am German local time ("Gas-Tag")

Now imagine there is an interface between two systems:

• one of your systems obeys all of the above rules
• but another one works differently (e.g. models end dates inclusively or is unaware of the differences between electricity and gas)

Then you need a conversion logic for your time.Times. This library does the conversion for you.

How To Use

See Go Playground for a minimal working example.

Note that this library only modifies timestamps, that are 06:00 German local time (if we're dealing with Gas) or 00:00 German local time (if we're not dealing with Gas). It won't shift arbitrary timestamps, so in most cases in your application you don't have to manually check if the conversion shall be applied to specific data constellations but only generally think about whether a time.Time is interpreted differently by different systems.

Code Quality / Production Readiness

• The code has 95% unit test coverage. ✔️
• The package has only one dependency itself (except for testing frameworks) ✔️:
  • go-playground/validator ️
• The code has no linter warnings in the default golangci-lint configuration. ✔️

Implicit Requirements

The package requires your relevant timezone data to be present on the system on which you're using it. It does not include timezone data itself and will panic if the local timezone data is not found. Please import the time/tzdata package from the std library, if necessary.

The package does not include any workarounds to actual timezone data (e.g. in the case of Germany calculating the last Sunday in March or October.) You can do it but you probably shouldn't.

mako_time_converter's Issues

Rationale clarification

The current "Rationale" section in README states:

and you shall always use UTC-offset 0 (which makes things unnecessary complicated)

Currently it reads like I shall use UTC offset 0 to make things unnecessary complicated, I guess that's not the intention.