1 liner load config package in Python 3 - python-3.x

I desesperatly searching for 1 liner load config package in Python 3...
In python 2, there is :
https://pypi.python.org/pypi/config/0.3.7
from config import Config; cfg = Config(file('D://config.py', 'r'))
There is
https://pypi.python.org/pypi/loadconfig
but it does not seem loading file...
Main goal is to install this package in all the python envs and load
one big config file for all envs.
Use case:
You have a single piece of python, you want to run on several hardware/OS and python envs (conda,...) without changing the code...
Method 1:
1) Define a generic config files for all Envs needed.
2) At RunTime, determine the environnment (linux, username, ) and
define the absolute path root repository directory with config file.
3) Single piece of code, running in different envs without changing the code, the envs...

From similar functionnalities than config
https://pypi.python.org/pypi/config/0.3.7
Security is not guaranted
config.py should not contains harmful python code.
from attrdict import AttrDict; f= open('USER_ROOT/config.py'); cfg = AttrDict(eval(f.read())); f.close()
cfg.key1
cfg.mykey2
cfg.mykey4

Related

Referencing a YAML config file, from Python, when a softlink is defined

I have the following code;
#!/usr/bin/env python3
import yaml
with open('config.yml', 'r') as config_file:
config = yaml.load(config_file)
The file is called __init__.py which is in the directory ~/bin/myprogram/myprogram/ and in the same directory, I have a file called config.yml
My symlink is as follows;
user$ ls -la /usr/local/bin/
lrwxr-xr-x 1 user admin 55 27 Nov 13:25 myprogram -> /Users/user/bin/myprogram/myprogram/__init__.py
Every time I run myprogram, I get the error FileNotFoundError: [Errno 2] No such file or directory: 'config.yml'. I believe this is because the config.yml is not in /usr/local/bin/. What is the best way to work around this issue?
You can use __file__ to access the location of the __init__.py file when executing code in that file. It returns the full path, but care has to be taken as it may be the .pyc (or .pyo) version. Since you are using Python3 I would use the pathlib module:
import yaml
from pathlib import Path
my_path = Path(__file__).resolve() # resolve to get rid of any symlinks
config_path = my_path.parent / 'config.yaml'
with config_path.open() as config_file:
config = yaml.safe_load(config_file)
Please note:
If you have to use PyYAML, use safe_load(), even PyYAML's own documentation indicates .load() can be unsafe. It almost never necessary to use that. And in the unlikely event that safe_load() cannot load your config, e.g. if it has !!python/... tags, you should explicitly add register the classes that you actually need to the SafeLoader).
Since September 2006 the recommended extension for YAML files has been .yaml

How to add a module folder /tar.gz to nodes in Pyspark

I am running pyspark in Ipython Notebook after doing following configuration
export PYSPARK_DRIVER_PYTHON=/usr/local/bin/jupyter
export PYSPARK_DRIVER_PYTHON_OPTS="notebook--NotebookApp.open_browser=False --NotebookApp.ip='*' --NotebookApp.port=8880"
export PYSPARK_PYTHON=/usr/bin/python
I am having a custom udf function, which makes use of a module called mzgeohash. But, I am getting module not found error, I guess this module might be missing in workers / nodes .I tried to add sc.addpyfile and all. But, what will be the effective way to add a cloned folder or tar.gz python module in this case , from Ipython .
Here is how I do it, basically the idea is to create a zip of all the files in your module and pass it to sc.addPyFile() :
import dictconfig
import zipfile
def ziplib():
libpath = os.path.dirname(__file__) # this should point to your packages directory
zippath = '/tmp/mylib-' + rand_str(6) + '.zip' # some random filename in writable directory
zf = zipfile.PyZipFile(zippath, mode='w')
try:
zf.debug = 3 # making it verbose, good for debugging
zf.writepy(libpath)
return zippath # return path to generated zip archive
finally:
zf.close()
...
zip_path = ziplib() # generate zip archive containing your lib
sc.addPyFile(zip_path) # add the entire archive to SparkContext
...
os.remove(zip_path) # don't forget to remove temporary file, preferably in "finally" clause

Loading python modules in Python 3

How do I load a python module, that is not built in. I'm trying to create a plugin system for a small project im working on. How do I load those "plugins" into python? And, instaed of calling "import module", use a string to reference the module.
Have a look at importlib
Option 1: Import an arbitrary file in an arbiatrary path
Assume there's a module at /path/to/my/custom/module.py containing the following contents:
# /path/to/my/custom/module.py
test_var = 'hello'
def test_func():
print(test_var)
We can import this module using the following code:
import importlib.machinery
myfile = '/path/to/my/custom/module.py'
sfl = importlib.machinery.SourceFileLoader('mymod', myfile)
mymod = sfl.load_module()
The module is imported and assigned to the variable mymod. We can then access the module's contents as:
mymod.test_var
# prints 'hello' to the console
mymod.test_func()
# also prints 'hello' to the console
Option 2: Import a module from a package
Use importlib.import_module
For example, if you want to import settings from a settings.py file in your application root folder, you could use
_settings = importlib.import_module('settings')
The popular task queue package Celery uses this a lot, rather than giving you code examples here, please check out their git repository

scons environment setup

Is there a way to tell scons to use a particular file to setup the default environment? I am using TI DSPs and the compiler is something different than cc; I'd like to have one "environment file" that defines where the compiler is, and what the default flags are, and then be able to use this for several projects.
Any suggestions?
You can use the normal python utilities to read a file or process XML and then import it into your env. If you don't have some external file that you need to import into SCons, then you can simply encode the environment in the scons file. If, for some reason, your environment is defined in a Perl dictionary ( as in my case...) you can either try to use PyPerl or convert the Perl dictionary into YAML and then read the YAML into python. ( I was able to do the later, but not the former).
Let's say you simply have a file that you need to read which has environment variables in the form:
ENV_VAR1 ENV_VAL1
ENV_VAR2 ENV_VAL2
...
You could import this into your SConstruct.py file like:
import os
env_file = open('PATH_TO_ENV_FILE','r')
lines = env.file.readlines()
split_regex = re.compile('^(?P<env_var>[\w_]+) *(?P<env_val>.*)')
for line in lines:
regex_search = split_regex.search(line)
if regex_search:
env_var = regex_search.group('env_var')
env_val = regex_search.group('env_val').strip()
os.environ[env_var] = env_val
base_env = Environment(ENV=os.environ)
# even though the below lines seem redundant, it was necessary in my build
# flow...
for key in os.environ.iterkeys():
base_env[key] = os.environ[key]
If you want to stick this ugliness inside a different file and then import it from your main SConstruct.py file, you can add the following to enable access to the 'Environment' class from your other file:
from SCons.Environment import *
Then in your main SConstruct.py file, import the env file like:
from env_loader import *
SInclusion file:
...
myenv = Environment(...)
...
SConstruct file:
...
execfile('SInclusion')
...
myenv.Object(...)
...

Py2exe: Embed static files in exe file itself and access them

I found a solution to add files in library.zip via: Extend py2exe to copy files to the zipfile where pkg_resources can load them.
I can access to my file when library.zip is not include the exe.
I add a file : text.txt in directory: foo/media in library.zip.
And I use this code:
import pkg_resources
import zipfile
from cStringIO import StringIO
my_data = pkg_resources.resource_string(__name__,"library.zip")
filezip = StringIO(my_data)
zip = zipfile.ZipFile(filezip)
data = zip.read("foo/media/text.txt")
I try to use pkg_resources but I think that I don't understand something because I could open directly "library.zip".
My question is how can I do this when library.zip is embed in exe?
Best Regards
Jean-Michel
I cobbled together a reasonably neat solution to this, but it doesn't use pkg_resources.
I need to distribute productivity tools as standalone EXEs, that is, all bundled into the one .exe file. I also need to send out notifications when these tools are used, which I do via the Logging API, using file-based configuration. I emded the logging.cfg fileto make it harder to effectively switch-off these notifications i.e. by deleting the loose file... which would probably break the app anyway.
So the following is the interesting bits from my setup.py:
LOGGING_CFG = open('main/resources/logging.cfg').read()
setup(
name='productivity-tool',
...
# py2exe extras
console=[{'script': productivity_tool.__file__.replace('.pyc', '.py'),
'other_resources': [(u'LOGGINGCFG', 1, LOGGING_CFG)]}],
zipfile=None,
options={'py2exe': {'bundle_files': 1, 'dll_excludes': ['w9xpopen.exe']}},
)
Then in the startup code for productivity_tool.py:
from win32api import LoadResource
from StringIO import StringIO
from logging.config import fileConfig
...
if __name__ == '__main__':
if is_exe():
logging_cfg = StringIO(LoadResource(0, u'LOGGINGCFG', 1))
else:
logging_cfg = 'main/resources/logging.cfg'
fileConfig(logging_cfg)
...
Works a treat!!!
Thank you but I found the solution
my_data = pkg_resources.resource_stream("__main__",sys.executable) # get lib.zip file
zip = zipfile.ZipFile(my_data)
data = zip.read("foo/media/doc.pdf") # get my data on lib.zip
file = open(output_name, 'wb')
file.write(data) # write it on a file
file.close()
Best Regards
You shouldn't be using pkg_resources to retrieve the library.zip file. You should use it to retrieve the added resource.
Suppose you have the following project structure:
setup.py
foo/
__init__.py
bar.py
media/
image.jpg
You would use resource_string (or, preferably, resource_stream) to access image.jpg:
img = pkg_resources.resource_string(__name__, 'media/image.jpg')
That should "just work". At least it did when I bundled my media files in the EXE. (Sorry, I've since left the company where I was using py2exe, so don't have a working example to draw on.)
You could also try using pkg_resources.resource_filename(), but I don't think that works under py2exe.

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