Ankit ankitml

Internet Scale Services Checklist

A checklist for designing and developing internet scale services, inspired by James Hamilton's 2007 paper "On Desgining and Deploying Internet-Scale Services."

http://mvdirona.com/jrh/talksandpapers/jamesrh_lisa.pdf

Basic tenets

Does the design expect failures to happen regularly and handle them gracefully?
Have we kept things as simple as possible?

underscore

Underscorejs port for python

Highlights

Works with python 3.
All methods are lazy and return generators (well almost all)

Why

Partially persistent Data Structures are the ones where we can go back and look at how the data looked like in history.

For this assignment, you have to implement Partially persistent Data structure (dictionary) in python, with any data store (redis, mongoDB, etc) with the following features.

A way to get latest state of dictionary. Or latest value of any key in dictionary.
A way to get historical version of dictionary.
History of any key in the dictionary.
Update the dictionary to a new version.

DevOps started out as "Agile Systems Administration". In 2008, Andrew Shafer did a talk called "Agile Infrastucture" addressing issues around involving more of the company in the same disciplines as programmers.

In 2009, Patrick Debois created "DevOpsDays" conference to help to bring it to light. However, it wouldn't begin to trend until about 2010, when people would begin to describe it as a standalone discipline.

Today, DevOps goes beyond just developers, systems administration and infrastructure, its about [dev, ops, agile, cloud, open source and business](https://blogs.the451group.com/opensource/2010/03/03/devops-mixing-dev-ops-agile-cloud-open-source-and-busi

	<?

	/**
	*
	* Connect to the database defined in config file.
	* @return - mysqli link object, Flase if error.
	*
	*/
	function connect_db() {
	global $CFG;

	from real_type import get_type
	#real type can be taken from https://github.com/ankitml/real_type or https://pypi.python.org/pypi/real_type/0.1

	def read_multiple_csv(files, key_header):
	"""
	takes a list of filesnames and a key_header string to merge the files.
	Can merge if there are different columns in the files, different records in
	the files.
	Assumption - all the files should have the column named key_header
	example : files = ['grades.csv', 'previous_grades.csv']

	from true_type import get_type
	import csv

	def get_percentile(data_list, score, kind='weak'):
	"""
	The percentile rank of a score relative to a list of scores.
	A percentile of, for example, 80 percent means that 80 percent of the
	scores in the data_list are below the given score.

	In the case of gaps or ties, the exact definition depends on the type

	Accompanies (http://iank.it/pluggable-filters-for-django-rest-framework/)


	class FiltersBackendBase:
	"""
	Base class to create FilterBackends
	FilterBackends are complementary classes that can be
	used with GenericFilterMixin
	"""

	3 def get_or_create_lti_user(tool_provider):
	2 email = tool_provider.get_param('lis_person_contact_email_primary')
	1 name = tool_provider.get_param('lis_person_name_full')
	4 userid = tool_provider.get_param('user_id')
	1 if userid is None or userid == "" :
	2 raise InvalidLTIRequestError('USERID NOT SENT BY CANVAS')
	3 if email is None or email == "":
	4 raise InvalidLTIRequestError('EMAIL NOT SENT BY CANVAS')
	5
	6

	from django.core.management.base import BaseCommand, CommandError
	from django_redis import get_redis_connection
	from django.db import DEFAULT_DB_ALIAS, connections
	from django.db.migrations.loader import MigrationLoader
	from django.core.management import call_command


	class Command(BaseCommand):
	help = """Interactive Django migrations. Supports +1/-1 interface for django migrations,
	similar to Alembic for SQLAlchemy. Also supports fast forward and fast rewind