t.rast.list: Add CSV, JSON, YAML outputs

[wenzeslaus]

• This adds CSV, JSON, and YAML output and generalizes the other outputs.
• Method is now meant only for different data gathering methods, not for the output formatting. method=cols and method=comma are now obsolete.
• All formatting is available with all methods.
• Most code is shared between the two main branches of code (simple list versus delta/gran methods code).
• Columns can be now specified for any option (previously only for cols/list and partially for comma/line output).
• The change is backwards compatible both on module interface level and on Python API level.

There is no performance penalty for the more general, step-by-step code (at least with smaller data; several tests with perf give all times around 1.7s with the 6 map test).

Binder link

[wenzeslaus]

New usage: Load JSON

import json

import grass.script as gs

result = json.loads(
    gs.read_command("t.rast.list", method="gran", input="precip_abs0", format="json")
)
names = [item["name"] for item in result["data"]]
dates = [item["start_time"] for item in result["data"]]
print(names)
print(dates)

Classic usage: Custom parsing

import grass.script as gs

rows = gs.read_command("t.rast.list", method="gran", input="precip_abs0").splitlines()

new_rows = [row.split("|") for row in rows]
new_array = [list(row) for row in zip(*new_rows)]

for column in new_array:
    if column[0] == "name":
        names = column[1:]
    if column[0] == "start_time":
        dates = column[1:]
print(names)
print(dates)

Both take approximately same time, approx 3.33s, with variations bigger than the difference.

[wenzeslaus]

This has tests, it doesn't change default behavior, and doesn't seem to have any performance issues, I plan to merge this soon still to be included to 8.2. Comments welcome.

[veroandreo]

I'd like to test it, but I can during the weekend only. Is that still good timing @wenzeslaus ?

[wenzeslaus]

That would be great. Thank you!

[veroandreo]

I've been testing different combinations of methods, columns and format options. I really like that method refers now to data gathering and format to printing.

I found however, that not all column possibilities can go with all methods, eg., columns min and max are not available for method gran or delta given the type of gathering I assume. Maybe document that (if not yet there) saying something like: columns can be specified for all methods and formats, but note that depending on the method some columns might not be available.

[wenzeslaus]

So, it actually needed fix for the checking, some valid columns were rejected and some other caused a traceback (relevant exception from the underlying function, just not appropriate in the module context). I added the fix, doc, and tests.