Miscellaneous modules¶

utils – utilities¶

Utility functions and classes.

summer.utils.locate_file(path_to_module: str, filename: str) → str[source]¶

Tries to locate the file in module path. Starts the search in current directory and goes up in directory structure until file is found or module namespace is left.

Parameters:	path_to_module (str) – directory path, ususally just pass in __file__ built-in filename (str) – file to look for

FIXME martin.slouf – now it only checks 3 levels up, instead of end of module namespace.

summer.utils.chunks(col: collections.abc.Iterable, chunk_size: int)[source]¶

Yield successive n-sized chunks from iterable.

Thanks to: http://stackoverflow.com/questions/312443/how-do-you-split-a-list-into-evenly-sized-chunks-in-python

Parameters:	col (collections.Iterable) – collection to be chunked chunk_size (int) – chunk size
Returns:	generator over collection of chunks (collection of original elements split into several smaller collections of chunk_size length)
Return type:	types.GeneratorType

class summer.utils.Printable[source]¶

Bases: object

Tries to pretty print object properties into a unicode string.

Suitable for multi-inheritance, see summer.model.Domain.

__str__()[source]¶

Return printable object string representation in unicode.

__bytes__()[source]¶

Return printable object representation in platform specific encoding.

__weakref__¶

list of weak references to the object (if defined)

class summer.utils.FileReader(fin: io.IOBase, enc: str)[source]¶

Bases: object

Simple & handy class for reading text file line by line with specified encoding. Converts line read to unicode. Counts line read. Does no file manipulation (opening, closing) except for reading. If used, you should delegate all reading to this simple class.

__init__(fin: io.IOBase, enc: str)[source]¶

Creates the FileReader instance.

Parameters:	fin (io.IOBase) – file-like object to be read enc (str) – file encoding

readline() → str[source]¶

Read single line from a file.

Returns:	line as unicode string.
Return type:	str

__weakref__¶

list of weak references to the object (if defined)

class summer.utils.ThreadSafeCounter(initial_value=0)[source]¶

Bases: object

Thread safe counter.

__init__(initial_value=0)[source]¶

Creates ThreadSafeCounter instance.

Parameters:	initial_value (int) – initial value

inc() → int[source]¶

Increase counter by 1 and return new value.

dec() → int[source]¶

Decrease counter by 1 and return new value.

__weakref__¶

list of weak references to the object (if defined)

class summer.utils.IdGenerator[source]¶

Bases: object

Thread safe id generator.

gen_id() → int[source]¶

Generates new id.

Returns:	new id
Return type:	int

__weakref__¶

list of weak references to the object (if defined)

class summer.utils.Singleton[source]¶

Bases: type

Metaclass that makes the class producing singleton instance.

class summer.utils.ConfigValue[source]¶

Bases: object

Configuration class that defines a default value while checking the os environment os.environ for a possible override.

convert_value_str(value_str: str, target_class: type) → object[source]¶

Utility method that converts a string value to proper type

Parameters:	value_str (str) – value to be converted target_class (type) – required target type
Returns:	Converted value or original one, if no conversion found.
Return type:	object

__weakref__¶

list of weak references to the object (if defined)

stringutils – string utilities¶

Utility string functions that should be probably part of Python stdlib.

EMPTY_STRING defines an empty string (ie. “”)

This module is not imported into public summer namespace, so you should import it directly:

from summer import stringutils

summer.stringutils.has_text(obj: object, strip: bool = True) → bool[source]¶

Check for text in string.

Parameters:	obj (object) – object to be tested strip (bool) – if True obj is stripped before checking
Returns:	True if obj is string and contains some non-white characters; False otherwise.
Return type:	bool

summer.stringutils.to_unicode(obj: object, encoding: str) → str[source]¶

Return unicode representation of an object.

Returns:	unicoce string object representation
Return type:	str

summer.stringutils.wrap(text: str, width: int) → str[source]¶

A word-wrap function that preserves existing line breaks and most spaces in the text. Expects that existing line breaks are posix newlines (\n).

Taken from: http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/148061/index_txt

Parameters:	text (str) – text to be wrapped width (int) – max number of characters in single line
Returns:	wrapped original text
Return type:	str

ipythonutils – ipython debugging support¶

Support for embedded IPython invocation.

This module is not imported into public summer namespace, so you should import it directly:

from summer import ipythonutils

summer.ipythonutils.run_ipshell(banner: str = None, local_variables: dict = None)[source]¶

Runs an embedded IPython interpretter at the place of your call.

To invoke the interpreter at the place of your choice:

from summer.ipythonutils import run_ipshell
run_ipshell()

Parameters:	banner (str) – banner (greeting) to be used local_variables (dict) – dictionary of variables accessible through l variable in invoked shell, defaults to current locals()

ass – assert¶

Provides various pre-implemented simple tests (ie. asserts) suitable for input argument testing.

This module is not imported into public summer namespace, so you should import it directly:

from summer import ass

exception summer.ass.AssertException(message: str = None, **kwargs)[source]¶

Bases: summer.ex.ApplicationException

Raised when some of the assertions methods in this module fails.

summer.ass.is_none(obj: object, msg: str = None, **kwargs) → bool[source]¶

Parameters:	obj (object) – object instance to be tested msg (str) – message in exception if test fails kwargs – arguments forwarded to exceptions (usually context values that are presented in stacktrace alongside the message.
Returns:	True if obj is None, False otherwise.
Return type:	bool

summer.ass.is_not_none(obj: object, msg: str = None, **kwargs) → bool[source]¶

Parameters:	obj (object) – object instance to be tested msg (str) – message in exception if test fails kwargs – arguments forwarded to exceptions (usually context values that are presented in stacktrace alongside the message.
Returns:	True if obj is not None, False otherwise.
Return type:	bool

summer.ass.is_true(expr: bool, msg: str = None, **kwargs) → bool[source]¶

Parameters:	expr (bool) – object instance to be tested msg (str) – message in exception if test fails kwargs – arguments forwarded to exceptions (usually context values that are presented in stacktrace alongside the message.
Returns:	True if expr is True, False otherwise.
Return type:	bool

summer.ass.is_false(expr: bool, msg: str = None, **kwargs) → bool[source]¶

Parameters:	expr (bool) – object instance to be tested msg (str) – message in exception if test fails kwargs – arguments forwarded to exceptions (usually context values that are presented in stacktrace alongside the message.
Returns:	True if expr is False, False otherwise.
Return type:	bool

summer.ass.has_text(obj: str, msg: str = None, **kwargs) → bool[source]¶

Parameters:	obj (str) – object instance to be tested msg (str) – message in exception if test fails kwargs – arguments forwarded to exceptions (usually context values that are presented in stacktrace alongside the message.
Returns:	True if obj is str and is not empty, False otherwise.
Return type:	bool

lod – list of dictionaries¶

List of dictionaries (lod) – simple yet powerfull in memory data structure, ie. grid.

Thanks to: http://stackoverflow.com/questions/1038160/python-data-structure-for-maintaing-tabular-data-in-memory

This module is not imported into public summer namespace, so you should import it directly:

from summer import lod

summer.lod.lod_populate(lod: list, fin: io.IOBase)[source]¶

Populate lod using CSV file.

Parameters:	lod (list) – list to be extended with data fin (io.IOBase) – file-like object in CSV format

summer.lod.lod_query(lod: list, filter_obj=None, sort_keys=None)[source]¶

Lookup in lod based on query.

Parameters:	lod (list) – lod to be used filter_obj – filter to be used sort_keys – sort criteria
Returns:	collection of matching rows
Return type:	list

summer.lod.lod_lookup(lod: list, **kw)[source]¶

Lookup in lod by attribute values.

Parameters:	lod (list) – lod to be used **kw (dict) – use keyword arguments. keys are column names, their value is attribute value
Returns:	first matching row
Return type:	list