Properties file in python (similar to Java Properties) - python

Given the following format (.properties or .ini):
propertyName1=propertyValue1
propertyName2=propertyValue2
...
propertyNameN=propertyValueN
For Java there is the Properties class that offers functionality to parse / interact with the above format.
Is there something similar in python's standard library (2.x) ?
If not, what other alternatives do I have ?

I was able to get this to work with ConfigParser, no one showed any examples on how to do this, so here is a simple python reader of a property file and example of the property file. Note that the extension is still .properties, but I had to add a section header similar to what you see in .ini files... a bit of a bastardization, but it works.
The python file: PythonPropertyReader.py
#!/usr/bin/python
import ConfigParser
config = ConfigParser.RawConfigParser()
config.read('ConfigFile.properties')
print config.get('DatabaseSection', 'database.dbname');
The property file: ConfigFile.properties
[DatabaseSection]
database.dbname=unitTest
database.user=root
database.password=
For more functionality, read: https://docs.python.org/2/library/configparser.html

For .ini files there is the configparser module that provides a format compatible with .ini files.
Anyway there's nothing available for parsing complete .properties files, when I have to do that I simply use jython (I'm talking about scripting).

I know that this is a very old question, but I need it just now and I decided to implement my own solution, a pure python solution, that covers most uses cases (not all):
def load_properties(filepath, sep='=', comment_char='#'):
"""
Read the file passed as parameter as a properties file.
"""
props = {}
with open(filepath, "rt") as f:
for line in f:
l = line.strip()
if l and not l.startswith(comment_char):
key_value = l.split(sep)
key = key_value[0].strip()
value = sep.join(key_value[1:]).strip().strip('"')
props[key] = value
return props
You can change the sep to ':' to parse files with format:
key : value
The code parses correctly lines like:
url = "http://my-host.com"
name = Paul = Pablo
# This comment line will be ignored
You'll get a dict with:
{"url": "http://my-host.com", "name": "Paul = Pablo" }

A java properties file is often valid python code as well. You could rename your myconfig.properties file to myconfig.py. Then just import your file, like this
import myconfig
and access the properties directly
print myconfig.propertyName1

if you don't have multi line properties and a very simple need, a few lines of code can solve it for you:
File t.properties:
a=b
c=d
e=f
Python code:
with open("t.properties") as f:
l = [line.split("=") for line in f.readlines()]
d = {key.strip(): value.strip() for key, value in l}

If you have an option of file formats I suggest using .ini and Python's ConfigParser as mentioned. If you need compatibility with Java .properties files I have written a library for it called jprops. We were using pyjavaproperties, but after encountering various limitations I ended up implementing my own. It has full support for the .properties format, including unicode support and better support for escape sequences. Jprops can also parse any file-like object while pyjavaproperties only works with real files on disk.

This is not exactly properties but Python does have a nice library for parsing configuration files. Also see this recipe: A python replacement for java.util.Properties.

i have used this, this library is very useful
from pyjavaproperties import Properties
p = Properties()
p.load(open('test.properties'))
p.list()
print(p)
print(p.items())
print(p['name3'])
p['name3'] = 'changed = value'

Here is link to my project: https://sourceforge.net/projects/pyproperties/. It is a library with methods for working with *.properties files for Python 3.x.
But it is not based on java.util.Properties

This is a one-to-one replacement of java.util.Propeties
From the doc:
def __parse(self, lines):
""" Parse a list of lines and create
an internal property dictionary """
# Every line in the file must consist of either a comment
# or a key-value pair. A key-value pair is a line consisting
# of a key which is a combination of non-white space characters
# The separator character between key-value pairs is a '=',
# ':' or a whitespace character not including the newline.
# If the '=' or ':' characters are found, in the line, even
# keys containing whitespace chars are allowed.
# A line with only a key according to the rules above is also
# fine. In such case, the value is considered as the empty string.
# In order to include characters '=' or ':' in a key or value,
# they have to be properly escaped using the backslash character.
# Some examples of valid key-value pairs:
#
# key value
# key=value
# key:value
# key value1,value2,value3
# key value1,value2,value3 \
# value4, value5
# key
# This key= this value
# key = value1 value2 value3
# Any line that starts with a '#' is considerered a comment
# and skipped. Also any trailing or preceding whitespaces
# are removed from the key/value.
# This is a line parser. It parses the
# contents like by line.

You can use a file-like object in ConfigParser.RawConfigParser.readfp defined here -> https://docs.python.org/2/library/configparser.html#ConfigParser.RawConfigParser.readfp
Define a class that overrides readline that adds a section name before the actual contents of your properties file.
I've packaged it into the class that returns a dict of all the properties defined.
import ConfigParser
class PropertiesReader(object):
def __init__(self, properties_file_name):
self.name = properties_file_name
self.main_section = 'main'
# Add dummy section on top
self.lines = [ '[%s]\n' % self.main_section ]
with open(properties_file_name) as f:
self.lines.extend(f.readlines())
# This makes sure that iterator in readfp stops
self.lines.append('')
def readline(self):
return self.lines.pop(0)
def read_properties(self):
config = ConfigParser.RawConfigParser()
# Without next line the property names will be lowercased
config.optionxform = str
config.readfp(self)
return dict(config.items(self.main_section))
if __name__ == '__main__':
print PropertiesReader('/path/to/file.properties').read_properties()

If you need to read all values from a section in properties file in a simple manner:
Your config.properties file layout :
[SECTION_NAME]
key1 = value1
key2 = value2
You code:
import configparser
config = configparser.RawConfigParser()
config.read('path_to_config.properties file')
details_dict = dict(config.items('SECTION_NAME'))
This will give you a dictionary where keys are same as in config file and their corresponding values.
details_dict is :
{'key1':'value1', 'key2':'value2'}
Now to get key1's value :
details_dict['key1']
Putting it all in a method which reads that section from config file only once(the first time the method is called during a program run).
def get_config_dict():
if not hasattr(get_config_dict, 'config_dict'):
get_config_dict.config_dict = dict(config.items('SECTION_NAME'))
return get_config_dict.config_dict
Now call the above function and get the required key's value :
config_details = get_config_dict()
key_1_value = config_details['key1']
-------------------------------------------------------------
Extending the approach mentioned above, reading section by section automatically and then accessing by section name followed by key name.
def get_config_section():
if not hasattr(get_config_section, 'section_dict'):
get_config_section.section_dict = dict()
for section in config.sections():
get_config_section.section_dict[section] =
dict(config.items(section))
return get_config_section.section_dict
To access:
config_dict = get_config_section()
port = config_dict['DB']['port']
(here 'DB' is a section name in config file
and 'port' is a key under section 'DB'.)

create a dictionary in your python module and store everything into it and access it, for example:
dict = {
'portalPath' : 'www.xyx.com',
'elementID': 'submit'}
Now to access it you can simply do:
submitButton = driver.find_element_by_id(dict['elementID'])

My Java ini files didn't have section headers and I wanted a dict as a result. So i simply injected an "[ini]" section and let the default config library do its job.
Take a version.ini fie of the eclipse IDE .metadata directory as an example:
#Mon Dec 20 07:35:29 CET 2021
org.eclipse.core.runtime=2
org.eclipse.platform=4.19.0.v20210303-1800
# 'injected' ini section
[ini]
#Mon Dec 20 07:35:29 CET 2021
org.eclipse.core.runtime=2
org.eclipse.platform=4.19.0.v20210303-1800
The result is converted to a dict:
from configparser import ConfigParser
#staticmethod
def readPropertyFile(path):
# https://stackoverflow.com/questions/3595363/properties-file-in-python-similar-to-java-properties
config = ConfigParser()
s_config= open(path, 'r').read()
s_config="[ini]\n%s" % s_config
# https://stackoverflow.com/a/36841741/1497139
config.read_string(s_config)
items=config.items('ini')
itemDict={}
for key,value in items:
itemDict[key]=value
return itemDict

This is what I'm doing in my project: I just create another .py file called properties.py which includes all common variables/properties I used in the project, and in any file need to refer to these variables, put
from properties import *(or anything you need)
Used this method to keep svn peace when I was changing dev locations frequently and some common variables were quite relative to local environment. Works fine for me but not sure this method would be suggested for formal dev environment etc.

import json
f=open('test.json')
x=json.load(f)
f.close()
print(x)
Contents of test.json:
{"host": "127.0.0.1", "user": "jms"}

I have created a python module that is almost similar to the Properties class of Java ( Actually it is like the PropertyPlaceholderConfigurer in spring which lets you use ${variable-reference} to refer to already defined property )
EDIT : You may install this package by running the command(currently tested for python 3).
pip install property
The project is hosted on GitHub
Example : ( Detailed documentation can be found here )
Let's say you have the following properties defined in my_file.properties file
foo = I am awesome
bar = ${chocolate}-bar
chocolate = fudge
Code to load the above properties
from properties.p import Property
prop = Property()
# Simply load it into a dictionary
dic_prop = prop.load_property_files('my_file.properties')

Below 2 lines of code shows how to use Python List Comprehension to load 'java style' property file.
split_properties=[line.split("=") for line in open('/<path_to_property_file>)]
properties={key: value for key,value in split_properties }
Please have a look at below post for details
https://ilearnonlinesite.wordpress.com/2017/07/24/reading-property-file-in-python-using-comprehension-and-generators/

you can use parameter "fromfile_prefix_chars" with argparse to read from config file as below---
temp.py
parser = argparse.ArgumentParser(fromfile_prefix_chars='#')
parser.add_argument('--a')
parser.add_argument('--b')
args = parser.parse_args()
print(args.a)
print(args.b)
config file
--a
hello
--b
hello dear
Run command
python temp.py "#config"

You could use - https://pypi.org/project/property/
eg - my_file.properties
foo = I am awesome
bar = ${chocolate}-bar
chocolate = fudge
long = a very long property that is described in the property file which takes up \
multiple lines can be defined by the escape character as it is done here
url=example.com/api?auth_token=xyz
user_dir=${HOME}/test
unresolved = ${HOME}/files/${id}/${bar}/
fname_template = /opt/myapp/{arch}/ext/{objid}.dat
Code
from properties.p import Property
## set use_env to evaluate properties from shell / os environment
prop = Property(use_env = True)
dic_prop = prop.load_property_files('my_file.properties')
## Read multiple files
## dic_prop = prop.load_property_files('file1', 'file2')
print(dic_prop)
# Output
# {'foo': 'I am awesome', 'bar': 'fudge-bar', 'chocolate': 'fudge',
# 'long': 'a very long property that is described in the property file which takes up multiple lines
# can be defined by the escape character as it is done here', 'url': 'example.com/api?auth_token=xyz',
# 'user_dir': '/home/user/test',
# 'unresolved': '/home/user/files/${id}/fudge-bar/',
# 'fname_template': '/opt/myapp/{arch}/ext/{objid}.dat'}

I did this using ConfigParser as follows. The code assumes that there is a file called config.prop in the same directory where BaseTest is placed:
config.prop
[CredentialSection]
app.name=MyAppName
BaseTest.py:
import unittest
import ConfigParser
class BaseTest(unittest.TestCase):
def setUp(self):
__SECTION = 'CredentialSection'
config = ConfigParser.ConfigParser()
config.readfp(open('config.prop'))
self.__app_name = config.get(__SECTION, 'app.name')
def test1(self):
print self.__app_name % This should print: MyAppName

This is what i had written to parse file and set it as env variables which skips comments and non key value lines added switches to specify
hg:d
-h or --help print usage summary
-c Specify char that identifies comment
-s Separator between key and value in prop file
and specify properties file that needs to be parsed eg : python
EnvParamSet.py -c # -s = env.properties
import pipes
import sys , getopt
import os.path
class Parsing :
def __init__(self , seprator , commentChar , propFile):
self.seprator = seprator
self.commentChar = commentChar
self.propFile = propFile
def parseProp(self):
prop = open(self.propFile,'rU')
for line in prop :
if line.startswith(self.commentChar)==False and line.find(self.seprator) != -1 :
keyValue = line.split(self.seprator)
key = keyValue[0].strip()
value = keyValue[1].strip()
print("export %s=%s" % (str (key),pipes.quote(str(value))))
class EnvParamSet:
def main (argv):
seprator = '='
comment = '#'
if len(argv) is 0:
print "Please Specify properties file to be parsed "
sys.exit()
propFile=argv[-1]
try :
opts, args = getopt.getopt(argv, "hs:c:f:", ["help", "seprator=","comment=", "file="])
except getopt.GetoptError,e:
print str(e)
print " possible arguments -s <key value sperator > -c < comment char > <file> \n Try -h or --help "
sys.exit(2)
if os.path.isfile(args[0])==False:
print "File doesnt exist "
sys.exit()
for opt , arg in opts :
if opt in ("-h" , "--help"):
print " hg:d \n -h or --help print usage summary \n -c Specify char that idetifes comment \n -s Sperator between key and value in prop file \n specify file "
sys.exit()
elif opt in ("-s" , "--seprator"):
seprator = arg
elif opt in ("-c" , "--comment"):
comment = arg
p = Parsing( seprator, comment , propFile)
p.parseProp()
if __name__ == "__main__":
main(sys.argv[1:])

Lightbend has released the Typesafe Config library, which parses properties files and also some JSON-based extensions. Lightbend's library is only for the JVM, but it seems to be widely adopted and there are now ports in many languages, including Python: https://github.com/chimpler/pyhocon

You can use the following function, which is the modified code of #mvallebr. It respects the properties file comments, ignores empty new lines, and allows retrieving a single key value.
def getProperties(propertiesFile ="/home/memin/.config/customMemin/conf.properties", key=''):
"""
Reads a .properties file and returns the key value pairs as dictionary.
if key value is specified, then it will return its value alone.
"""
with open(propertiesFile) as f:
l = [line.strip().split("=") for line in f.readlines() if not line.startswith('#') and line.strip()]
d = {key.strip(): value.strip() for key, value in l}
if key:
return d[key]
else:
return d

this works for me.
from pyjavaproperties import Properties
p = Properties()
p.load(open('test.properties'))
p.list()
print p
print p.items()
print p['name3']

I followed configparser approach and it worked quite well for me. Created one PropertyReader file and used config parser there to ready property to corresponding to each section.
**Used Python 2.7
Content of PropertyReader.py file:
#!/usr/bin/python
import ConfigParser
class PropertyReader:
def readProperty(self, strSection, strKey):
config = ConfigParser.RawConfigParser()
config.read('ConfigFile.properties')
strValue = config.get(strSection,strKey);
print "Value captured for "+strKey+" :"+strValue
return strValue
Content of read schema file:
from PropertyReader import *
class ReadSchema:
print PropertyReader().readProperty('source1_section','source_name1')
print PropertyReader().readProperty('source2_section','sn2_sc1_tb')
Content of .properties file:
[source1_section]
source_name1:module1
sn1_schema:schema1,schema2,schema3
sn1_sc1_tb:employee,department,location
sn1_sc2_tb:student,college,country
[source2_section]
source_name1:module2
sn2_schema:schema4,schema5,schema6
sn2_sc1_tb:employee,department,location
sn2_sc2_tb:student,college,country

You can try the python-dotenv library. This library reads key-value pairs from a .env (so not exactly a .properties file though) file and can set them as environment variables.
Here's a sample usage from the official documentation:
from dotenv import load_dotenv
load_dotenv() # take environment variables from .env.
# Code of your application, which uses environment variables (e.g. from `os.environ` or
# `os.getenv`) as if they came from the actual environment.

Related

Expanding a Scribunto module that doesn't have a function

I want to get the return value of this Wikimedia Scribunto module in Python. Its source code is roughly like this:
local Languages = {}
Languages = {
["aa"] = {
name = "afarština",
dir = "ltr",
name_attr_gen_pl = "afarských"
},
-- More languages...
["zza"] = {
name = "zazaki",
dir = "ltr"
}
}
return Languages
In the Wiktextract library, there is already Python code to accomplish similar tasks:
def expand_template(sub_domain: str, text: str) -> str:
import requests
# https://www.mediawiki.org/wiki/API:Expandtemplates
params = {
"action": "expandtemplates",
"format": "json",
"text": text,
"prop": "wikitext",
"formatversion": "2",
}
r = requests.get(f"https://{sub_domain}.wiktionary.org/w/api.php",
params=params)
data = r.json()
return data["expandtemplates"]["wikitext"]
This works for languages like French because there the Scribunto module has a well-defined function that returns a value, as an example here:
Scribunto module:
p = {}
function p.affiche_langues_python(frame)
-- returns the needed stuff here
end
The associated Python function:
def get_fr_languages():
# https://fr.wiktionary.org/wiki/Module:langues/analyse
json_text = expand_template(
"fr", "{{#invoke:langues/analyse|affiche_langues_python}}"
)
json_text = json_text[json_text.index("{") : json_text.index("}") + 1]
json_text = json_text.replace(",\r\n}", "}") # remove tailing comma
data = json.loads(json_text)
lang_data = {}
for lang_code, lang_name in data.items():
lang_data[lang_code] = [lang_name[0].upper() + lang_name[1:]]
save_json_file(lang_data, "fr")
But in our case we don't have a function to call.
So if we try:
def get_cs_languages():
# https://cs.wiktionary.org/wiki/Modul:Languages
json_text = expand_template(
"cs", "{{#invoke:Languages}}"
)
print(json_text)
we get <strong class="error"><span class="scribunto-error" id="mw-scribunto-error-0">Chyba skriptu: Musíte uvést funkci, která se má zavolat.</span></strong> usage: get_languages.py [-h] sub_domain lang_code get_languages.py: error: the following arguments are required: sub_domain, lang_code. (Translated as "You have to specify a function you want to call. But when you enter a function name as a parameter like in the French example, it complains that that function does not exist.)
What could be a way to solve this?
The easiest and most general way is to get the return value of the module as JSON and parse it in Python.
Make another module that exports a function dump_as_json that takes the name of the first module as a frame argument and returns the first module as JSON. In Python, expand {{#invoke:json module|dump_as_json|Module:module to dump}} using the expandtemplates API and parse the return value of the module invocation as JSON with json.loads(data["expandtemplates"]["wikitext"]).
Text of Module:json module (call it what you want):
return {
dump_as_json = function(frame)
local module_name = frame.args[0]
local json_encode = mw.text.jsonEncode
-- json_encode = require "Module:JSON".toJSON
return json_encode(require(module_name))
end
}
With pywikibot:
from pywikibot import Site
site = Site(code="cs", fam="wiktionary")
languages = json.loads(site.expand_text("{{#invoke:json module|dump_as_json|Module:module to dump}}")
If you get the error Lua error: Cannot pass circular reference to PHP, this means that at least one of the tables in Module:module to dump is referenced by another table more than once, like if the module was
local t = {}
return { t, t }
To handle these tables, you will have to get a pure-Lua JSON encoder function to replace mw.text.jsonEncode, like the toJSON function from Module:JSON on English Wiktionary.
One warning about this method that is not relevant for the module you are trying to get: string values in the JSON will only be accurate if they were NFC-normalized valid UTF-8 with no special ASCII control codes (U+0000-U+001F excluding tab U+0009 and LF U+000A) when they were returned from Module:module to dump. As on a wiki page, the expandtemplates API will replace ASCII control codes and invalid UTF-8 with the U+FFFD character, and will NFC-normalize everything else. That is, "\1\128e" .. mw.ustring.char(0x0301) would be modified to the equivalent of mw.ustring.char(0xFFFD, 0xFFFD, 0x00E9). This doesn't matter in most cases (like if the table contains readable text), but if it did matter, the JSON-encoding module would have to output JSON escapes for non-NFC character sequences and ASCII control codes and find some way to encode invalid UTF-8.
If, like the module you are dumping, Module:module to dump is a pure table of literal values with no references to other modules or to Scribunto-only global values, you could also get its raw wikitext with the Revisions API and parse it in Lua on your machine and pass it to Python. I think there is a Python extension that allows you to directly use a Lua state in Python.
Running a module with dependencies on the local machine is not possible unless you go to the trouble of setting up the full Scribunto environment on your machine, and figuring out a way to download the module dependencies and make them available to the Lua state. I have sort of done this myself, but it isn't necessary for your use case.

ConfigObj change key=value to key = value which I don't want to

I have conf file with content:
key1=value1
key2=value2
font="\"Font\""
and it's used like values in bash script.
When I change some value with cgi+python3 and ConfigObj 4.7.0:
def set_conf_values(filename, param, value):
config = ConfigObj(filename)
config['%s' % param] = value
config.write()
the conf file is rewriten and the format is new:
key1 = value1
key2 = value2
font = `\"Font\"`
Event for values which is untouched.
That's break my Bash script it takes keys as commands...
I hope there is option to avoid that but can't find such thing in docs.
There does not seem to be any meaningful way to control the output of ConfigObj. ConfigParser, though, has a space_around_delimiters=False keyword argument that you can pass to write.
config.conf:
[section1]
key1=value1
key2=value2
font="\"Font\""
code:
import configparser
from validate import Validator
def set_conf_values(filename, section, param, value):
config = configparser.ConfigParser()
config.read(filename)
print({section: dict(config[section]) for section in config.sections()})
config[section]['%s' % param] = value
with open('config2.conf', 'w') as fid:
config.write(fid, space_around_delimiters=False)
filename = 'config.conf'
set_conf_values(filename, 'section1', 'key2','value2_modified')
config2.conf (output):
[section1]
key1=value1
key2=value2_modified
font="\"Font\""
The dreadful thing about ConfigParser is that it REALLY wants section names. There are elaborate workarounds for this, but this code will get you started.

Self-Updating Code?

I have a module that needs to update new variable values from the web, about once a week. I could place those variable values in a file & load those values on startup. Or, a simpler solution would be to simply auto-update the code.
Is this possible in Python?
Something like this...
def self_updating_module_template():
dynamic_var1 = {'dynamic var1'} # some kind of place holder tag
dynamic_var2 = {'dynamic var2'} # some kind of place holder tag
return
def self_updating_module():
dynamic_var1 = 'old data'
dynamic_var2 = 'old data'
return
def updater():
new_data_from_web = ''
new_dynamic_var1 = new_data_from_web # Makes API call. gets values.
new_dynamic_var2 = new_data_from_web
# loads self_updating_module_template
dynamic_var1 = new_dynamic_var1
dynamic_var2 = new_dynamic_var2
# replace module place holders with new values.
# overwrite self_updating_module.py.
return
I would recommend that you use configparser and a set of default values located in an ini-style file.
The ConfigParser class implements a basic configuration file parser
language which provides a structure similar to what you would find on
Microsoft Windows INI files. You can use this to write Python programs
which can be customized by end users easily.
Whenever the configuration values are updated from the web api endpoint, configparser also lets us write those back out to the configuration file. That said, be careful! The reason that most people recommend that configuration files be included at build/deploy time and not at run time is for security/stability. You have to lock down the endpoint that allows updates to your running configuration in production and have some way to verify any configuration value updates before they are retrieved by your application:
import configparser
filename = 'config.ini'
def load_config():
config = configparser.ConfigParser()
config.read(filename)
if 'WEB_DATA' not in config:
config['WEB_DATA'] = {'dynamic_var1': 'dynamic var1', # some kind of place holder tag
'dynamic_var2': 'dynamic var2'} # some kind of place holder tag
return config
def update_config(config):
new_data_from_web = ''
new_dynamic_var1 = new_data_from_web # Makes API call. gets values.
new_dynamic_var2 = new_data_from_web
config['WEB_DATA']['dynamic_var1'] = new_dynamic_var1
config['WEB_DATA']['dynamic_var2'] = new_dynamic_var2
def save_config(config):
with open(filename, 'w') as configfile:
config.write(configfile)
Example usage::
# Load the configuration
config = load_config()
# Get new data from the web
update_config(config)
# Save the newly updated configuration back to the file
save_config(config)

Python- how can I set the value for params from another file

I am new to Python. I have to edit some test I have.
I have a file which inclused all the details for a test I have to execute. The file name for example is "test 1"
In this file there are few global params:
LINK_IP_ADDR = "10.8.22.89"
STABILITY_SLEEP = 5
MAIN_STATE_SLEEP = 30
For making the tests automaticly and generic I want to set the the value from the params from another python file (for example config_file). How should I do it?
You should probably use configuration files for this. The ConfigParser package would do the job.
If you want a quick and dirty version, the following could be for you.
In your 'test files', write the following:
class Params:
LINK_IP_ADDR = "10.8.22.89"
STABILITY_SLEEP = 5
MAIN_STATE_SLEEP = 30
Then in your main program you import the parameters you want and just use them:
from test1 import Params
# from test2 import Params
print Params.LINK_IP_ADDR
You can then switch your import statements to the file you want to use. I would use a normal .ini file with different sections though.
Here is a quick n' dirty way from a plain file:
params = dict()
with open('config_file') as f:
for line in f:
param, value = line.split("=")
params[param.strip()] = value.strip()
print(params)
config_file:
LINK_IP_ADDR = "10.8.22.89"
STABILITY_SLEEP = 5
MAIN_STATE_SLEEP = 30
for config file i used .yaml file. This format stores your config like json or python-dict. U can store complex structure (array, hashmap, ...) very good
config.yaml
LINK_IP_ADDR: 10.8.22.89
STABILITY_SLEEP: 5
MAIN_STATE_SLEEP: 30
another.py
import yaml
configs = yaml.safe_load(file("path_to_config.yaml"))
# to use you configs:
configs['LINK_IP_ADDR']
#.....

Python config parser that supports section inheritance?

I'm looking for an ini style config parser in Python that supports section inheritance similar to what Zend_Config_Ini does in PHP.
Does such a module exist or will I need to roll my own?
Python's ConfigParser can load multiple files. Files read later on can
override settings from the first file.
For example, my application has database settings in its internal default
configuration file:
[database]
server = 127.0.0.1
port = 1234
...
I override these on a different server with a "environment.ini" file containing
the same section but different values:
[database]
server = 192.168.0.12
port = 2345
...
In Python:
import os
from ConfigParser import ConfigParser
dbconf = ConfigParser()
dbconf.readfp(open('default.ini'))
if os.path.exists('environment.ini'):
dbconf.readfp(open('environment.ini'))
dbconf.get('database', 'server') # Returns 192.168.0.12
Here's what I used. extended_get method is what you need - it supports hierarchical sections.
import re
import io
import ConfigParser
class ZendConfigParser(ConfigParser.ConfigParser):
def extended_get(self, section, key):
if self.has_option(section, key):
return self.get(section, key)
else:
orig_section, parent_section = self._get_orig_section(section)
if orig_section != None:
if self.has_option(orig_section,key):
return self.get(orig_section,key)
else:
return self.extended_get(parent_section,key)
else:
return None
def _get_orig_section(self, zend_section):
orig_section = None
parent_section = None
for section in self.sections():
if re.search(r'^[ \t]*' + zend_section + '\\b', section) != None:
orig_section = section
#look for a parent section
match = re.match(r'\w+[ \t]*:[ \t]*(\w+)$', section)
if match != None:
parent_section = match.groups()[0]
break
return (orig_section, parent_section)
config = ZendConfigParser()
config.read(file)
print(config.extended_get('production', 'database.params.host'))
I also did not find any ready solution. To solve it, I adapted the get function of ConfigParser to search in the child section and afterwards in the parent section:
config = SafeConfigParser()
config.read(filenames)
required_environment = "mysection"
# determine fallback requirement in case parameter is not found in required environment
fallback_environment = "default"
# loop through all sections of config files
for environment in config.sections():
# check whether we find an inheritance based on the required section
if re.search(required_environment + " *: *\w+", environment):
# found inheritance, take parent as fallback section
fallback_environment = re.sub(required_environment + r" : (\w+)", r"\1", environment)
# take this name as requested section
required_environment = environment
# override get method
_config_parser_get = config.get
def myConfigParserGet(id):
# check different sections for desired value
if config.has_option(required_environment, id):
return _config_parser_get(required_environment, id)
else:
return _config_parser_get(fallback_environment, id)
config.get = myConfigParserGet
Restrictions:
only read-only access to config supported
only one level of inheritance

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