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• Rancher

  • most interesting thing to me in the interface is workers->pods

• Two ways to run stuff

  • via yaml
  • via kubernetes CLI / kubectl

• Via yaml:

  • change docker image and pod name
  • you can use a command in the yaml syntax run in interactive-ish mode, ignoring the Docker command, to execute stuff inside the running docker image.

    - name: podname
     image: "docker/image"
     command:
     - /bin/sh
     - -c
     - while true; do echo $(date) >> /tmp/out; sleep 1; done
    

• Kubernetes Workloads and Pods | Rancher Manager

  • Pods are groups of containrs that share network and storage, usually it’s one container

• Assigning Pods to Nodes | Kubernetes:

  • nodeName is a simple direct way

    metadata:
      name: nginx
    spec:
      containers:
      - name: nginx
        image: nginx
      nodeName: kube-01 
    

• don’t create branches / merge requests until I start working on the ticket - don’t do many at the same time either, harder and then rebasings needed
• delete branches after they get merged to main (automatically) - sometimes I didn’t to play it safe but never needed it and have them locally regardless
• Most of my code is more complex and more layers of abstraction than actually needed, and gets worse with later fixes. Don’t aim for abstraction before abstraction is needed
• When solving complex-er merge conflicts, sometimes this helps: first leave all imports, merge the rest, and then clean up the remaining imports

TIL - when looking how to clean printer heads - that some printers can do it automatically! Can be started both through the OS GUI or the printer itself (if it has buttons and stuff).

Wikihow (lol) as the first result in Google gave me enough to learn about automatic cleaning being a thing: How to Clean Print Heads: Clogged & Dried Up Print Heads; How to Clean a Printhead for Better Ink Efficiency < Tech Takes - HP.com Singapore +

Seen first in 230228-1835 Python Callable Protocols for complex Callable typing.

• As a placeholder (a la pass)
• In type hints: either “arbitrary number of” or relaxing constraintsn
  • See When Do You Use an Ellipsis in Python? – Real Python for examples

If you need to add typing to a complex Callable, with, say, parameter names etc., there are Callback Protocols.

# NB "self" is included!
class Combiner(Protocol):
    def __call__(self, *vals: bytes, maxlen: Optional[int] = None) -> list[bytes]: ...

def batch_proc(data: Iterable[bytes], cb_results: Combiner) -> bytes:
    for item in data:

Python 3.7 needs typing_extensions, 3.8+ support it natively.

See also: python typing signature (typing.Callable) for function with kwargs - Stack Overflow

Was doing a graph-like stucture to easily explain a really complex decision tree that’s not really a tree, but I was really looking for an existing thing: A state machine!

And it’s even an existing programming pattern: StateMachine — Python 3 Patterns, Recipes and Idioms

The book I didn’t know I needed!

Anyway, existing implementations:

• GitHub - fgmacedo/python-statemachine: Python Finite State Machines made easy.
• GitHub - pytransitions/transitions: A lightweight, object-oriented finite state machine implementation in Python with many extensions

I really like how feature-complete and documented transitions is - callbacks etc.

git diff [--options] <commit> <commit> [--] [<path>...]

For example, for ‘between now and 2 commits back’:

$ git diff HEAD^^ HEAD main.c
$ git diff HEAD~2 HEAD -- main.c

Paths need to be relative to the root of the repo.

Another option (can do different files) is:

git diff <revision_1>:<file_1> <revision_2>:<file_2>

Source: git - How do I diff the same file between two different commits on the same branch? - Stack Overflow

(Bonus: the -- makes it work for files with weird names like -p, good for scripts but rarely needed in practice).

Previously: 230221-1406 Gitlab has a git graph and comparisons

From How to use skip and xfail to deal with tests that cannot succeed — pytest documentation on dynamically skipping tests based on a condition:

@pytest.mark.skipif(sys.version_info < (3, 10), reason="requires python3.10 or higher")
def test_function():

Better than my previous approach of if xxx: pytest.skip("...") inside the tests themselves.

Adventures in cross-platform programming: I used fnmatch to basically simulate globs in a place where regexes were overkill, but not for filenames.

On windows, paths are case insensitive and therefore fnmatch is case insensitive too, leading to unexpected behaviour.

fnmatchcase() is case-sensitive regardless of OS.

TIL Gitlab has

• a Graph a la tig / pycharm log /. .., located at “Repository -> Graph”. Really neat
• “compare” right under it to quickly compare different branches/revisions

I should play more with the existing interfaces of things I use often