somutils 1.8.2

Tools we use at Somenergia and can be useful

somenergia-utils

This module includes different Python modules and scripts ubiquiously used on scripts in SomEnergia cooperative but with no entity by themselves to have their own repository.

• venv: script to run a command under a Python virtual enviroment
• sql2csv.py: script to run parametrized sql queries and get the result as (tab separated) csv.
• tsv: module for quick TSV serialization (csv with tabs as separators) of yamlns.namespace and dict like objects
  • tsvread: provides TSV rows as yamlns.namespaces (dict specialization)
  • tsvwrite: writes a TSV from a sequence of dicts
• dbutils.py: module with db related functions
  • runsql: runs a file with a sql and returns the objects as yamlns namespaces
  • runsql_cached: like runsql but cache the results in a tsv file to avoid second runs
  • fetchNs: a generator that wraps db cursors to fetch objects with attributes instead of psycopg arrays
  • nsList: uses the former to build a list of such object (slower but maybe convinient)
  • csvTable: turns the results of a query into a tab separated table with proper header names
• isodates: String to time/date/datetime objects with naive/timezoned handling
• sheetfetcher.py: convenience class to retrieve data from gdrive spreadshets
• trace: quickly enable and disable tracing function calling by decorating them with @trace
• testutils: module with common test utilities
  • testutils.destructiveTest: decorator to avoid running destructive tests in production
  • testutils.temp_path: context manager that provides a selfdestructing temporary directory for tests
  • testutils.working_dir: context manager that changes the current working directory and restores it afterwards
  • testutils.sandbox_dir: context manager that combines temp_path and working_dir
• erptree: extracts an object and its children from the erp (erppeek, odoo) with controlled recursion

venv script

Simplifies running a Python script under a given virtual environtment. This is specially useful to run Python scripts from crontab lines.

usage: venv /PATH/TO/PYTHON/VIRTUALENV COMMAND [PARAM1 [PARAM2...]]

sql2csv.py script

Runs an SQL file and outputs the result of the query as tabulator separated csv.a

A local config.py file is required, or you should provide it as -C file.py It should contain a dict named pyscopg with the keyword parameters to psycopg2.connect.

You can provide query parameters either as yamlfile or as commandline options.

 sql2csv.py <sqlfile> [<yamlfile>] [--<var1> <value1> [--<var2> <value2> ..] ]

dbutils Python module

Convenient database access

Having a query in a file.

params = dict(
   param1='value',
   param2=[1,3,4,5], # Useful for the IN clause
)
for item in runsql('myquery.sql', **params):
   print(item.id, item.description) # id and description should be columns in the query

Like sql2csv there must exist a config.py file or provide it with the config keyword parameter

Parameters are inserted as specified in psycopg2 documentation

TODO: db and cursor parameters to reuse existing ones.

If you know the results will be always the same, you can use runsql_cache instead. It will generate a tsv file name like the sql file with the results, and will use it instead of the query for next executions.

The usage of runsql_cache is quite similar to runsql to be exchangeable. runsql_cache just adds a couple of keyword arguments.

• cachefile: to override the default cache file (a name, a path or a file like object)
• force: to force the query execution even if the cache exists

Cursor wrappers

Convenient cursor wrappers to make the database access code more readable.

Example:

import psycopg2, dbutils
db = psycopg2.connect(**dbconfiguration)
with db.cursor() as cursor :
	cursor.execute("SELECT name, age FROM people")
	for person as dbutils.fetchNs(cursor):
		if person.age < 21: continue
		print("{name} is {age} years old".format(person))

sheetfetcher Python module

Convenient wraper for gdrive.

from sheetfetcher import SheetFetcher

fetcher = SheetFetcher(
	documentName='My Document',
	credentialFilename='drive-certificate.json',
	)
table = fetcher.get_range("My Sheet", "A2:F12")
fulltable = fetcher.get_fullsheet("My Sheet")

• Document selectors can be either an uri or the title
• Sheet selectors can be either an index, a name or an id.
• Range selectors can be either a named range, index tuple or a "A2:F5" coordinates.
• You should Create a certificate and grant it access to the document

trace

This decorator is a fast helper to trace calls to functions and methods. It will show the name of the functions the values of the parameters and the returned values.

from trace import trace

@trace
def factorial(n):
    if n<1: return 1
    return n*factorial(n-1)

factorial(6)

('> factorial', (6,))
('> factorial', (5,))
('> factorial', (4,))
('> factorial', (3,))
('> factorial', (2,))
('> factorial', (1,))
('> factorial', (0,))
('< factorial', (0,), '->', 1)
('< factorial', (1,), '->', 1)
('< factorial', (2,), '->', 2)
('< factorial', (3,), '->', 6)
('< factorial', (4,), '->', 24)
('< factorial', (5,), '->', 120)
('< factorial', (6,), '->', 720)

testutils.assertNsEqual

Allows to assert equality on json/yaml like structures combining dicts, lists, numbers, strings, dates... The comparision is done on the YAML output so that differences are spoted as text diffs. Also keys in dicts are alphabetically sorted.

testutils.destructiveTest

An utility to avoid running destrutive tests in production. It is a decorator that checks wheter the erp configured in dbconfig has the testing flag and skips the test if it doesn't.

The script enable_destructive_test.py is also provided to set/unset that testing flag which is not defined by default.

isodates

Module for simplified isodate parsing and timezone handling.

sequence

Interprets strings like the ones the standard Print Dialog uses to specify pages to be printed. ie. "2,4,6-9,13" means "2, 4, from 6 to 9 and 13"

erptree

Creates an structure from ERP objects that you can navigate or dump as yaml. You can select fields to expand, taking just the name or the id, anonymize or removing. You can use dot notation to specify fields in related objects. For multiple relations, a subfield refers to the subfield in all related objects.

from somutils.erptree import erptree

O = Client(....)

partner = erptree(partnerAddress_id, O.ResPartnerAddress,
	expand = {
		'partner_id': O.ResPartner,
		'partner_id.company': O.ResPartner,
	},
	pickName = [
		'partner_id.state_id',
		'partner_id.country_id',
	],
	anonymize = [
		'email',
	],
	remove = [
		'superfluous_field',
	],
)