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@lecram
Last active August 27, 2021 07:05
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This is a toy one-file application to manage persistent key-value string data. The file is *both* the application and its data. When you run any of the commands described in `escher.py --help`, the file will be executed and, after data change, it will rewrite itself with updated data. You can copy the file with whatever name to create multiple d…
#! /usr/bin/env python
"""{escher} -- one-file key-value storage.
What?
This is a toy application to manage persistent key-value string data.
The file {escher} is *both* the application and its data.
When you run any of the commands below, the file will be executed and,
after data change, it will rewrite itself with updated data.
You can copy the file with whatever name to create multiple datasets.
Remember that the data will be copied with the file. Each file must
be readable, writable, and executable.
Why?
I don't know; this is probably useless.
Usage:
Listing current keys:
$ {escher}
Getting the value of the foo key:
$ {escher} foo
(NOTE: If foo is not in the dataset, exit code will be 1.)
Setting the value of foo to bar:
$ {escher} foo bar
Removing the key foo:
$ {escher} foo ""
(NOTE: If foo is not in the dataset, exit code will be 1.)
Removing everything:
$ {escher} --clean
Printing this help message:
$ {escher} --help
"""
from __future__ import print_function
import sys
import os
import pickle
import zlib
import base64
__doc__ = __doc__.format(escher=os.path.basename(__file__))
sep = "--//--"
f = open(__file__, "r")
esc, her = f.read().split(repr(sep), 1)
f.close()
data = pickle.loads(zlib.decompress(base64.b64decode(her[1:].strip())))
args = sys.argv[1:]
print([
lambda : "\n".join(sorted(data.keys())) if data else
sys.exit(),
lambda key : __doc__ if key == "--help" else
not data.clear() and "X *" if key == "--clean" else
data.get(key, False) or
sys.exit("Error: key not found."),
lambda key, value : not data.update([(key, value)]) and
" ".join([key, "<-", value]) if value else
data.pop(key, True) and "X " + key if key in data else
sys.exit("Error: key not found."),
lambda fu, ti, le : print("Error: invalid argument list.") or sys.exit(2)
][min(len(args), 3)](*args[:3]))
her = base64.b64encode(zlib.compress(pickle.dumps(data, 2))).decode('ascii')
out = repr(sep).join([esc, "\n#" + her + "\n"])
with open(__file__, "w") as f: f.write(out)
'--//--'
#eJxrYKotZNADAAaFAZ8=
@shenanigans
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I thought you were just supposed to say "Hadoop" three times and drop your wallet on the floor?

@shabda
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shabda commented Dec 14, 2012

@chewxy

, chuck redis in and mongodb or something.

Chuck Norris in and mongodb or something.

@Ivanca
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Ivanca commented Dec 14, 2012

I can see why you are programmers and not comedians.

@kennethreitz
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Haha, I wrote one of these myself, several years ago:

https://gist.github.com/477550

@lecram
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lecram commented Dec 14, 2012

@mdda
I couldn't reproduce any problem with '}' characters. Perhaps your shell uses then for substitution? Did you try enclosing the arguments in quotes? Can you show an example that doesn't work so I can try to fix it?

@saml
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saml commented Dec 15, 2012

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