by Santosh Yadav
on May 21, 2019
Microservice is an architectural pattern, or we could say a system design pattern. It is based on Service Oriented Architecture.
Service Oriented architecture (SOA)
Service based architecture is a way of designing your system or applications in such a way that whole system is divided into small individual components where each provide different services to each other component over standard communication protocol shared by all the components, and together they are a complete system providing a useful service to other system/end user.
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by Ramesh Natarajan
on April 16, 2019
In AWS, whether you perform an action from Console, use AWS CLI, use AWS SDK, or when a AWS service does an action on your behalf, all of those API activities are logged in AWS CloudTrail.
This tutorials explains the following 7 essential AWS Cloudtrail best practices with examples on how to do it from both Console and using AWS CloudTrail CLI command.
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by Santosh Yadav
on April 10, 2019
REST stands for Representational State Transfer.
It is an architectural style, set of rules to standardize the web, to maintain uniformity across web applications worldwide. It intends to enhance maintainability, scalability, reliability and portability of web applications.
Main idea behind REST is resources. Everything you want to access in a web application is a resource, whether it is a media or documents you want to download, update, delete. REST defines a way to access, transfer, and modify these resources.
This tutorial covers the following three high-level concepts:
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by Ramesh Natarajan
on April 9, 2019
It is easier to manager AWS S3 buckets and objects from CLI. This tutorial explains the basics of how to manage S3 buckets and its objects using aws s3 cli using the following examples:
For quick reference, here are the commands. For details on how these commands work, read the rest of the tutorial.
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by Santosh Yadav
on April 4, 2019
Sets are basically collection of certain items that are unordered. There is no specific order in which they are stored. In Python sets are same, but there are few differences with basic sets.
- The elements in python sets are unique, there can’t be duplicate items in python sets. If duplicate items entered, it will be ignored and final set will always contain unique elements.
- Python sets are mutable. But, its elements are immutable. Once entered items cannot be modified.
- Python set’s item cannot be accessed using indexes. There is no index attached to set items.
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by Santosh Yadav
on April 2, 2019
What is Elasticsearch? In simple terms, we could possibly say elastic search is a NoSQL database. Since there are so many NoSQL databases, let us understand how Elasticsearch is different from them.
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by Santosh Yadav
on March 27, 2019
Tuple is similar to List in python language, both are sequential, index based data structure.
The main difference between tuples and list is that tuples are immutable i.e. we cannot modify a tuple’s content but List is mutable data structure. Also, tuples uses parenthesis and list uses square brackets.
This article will discuss about following in Tuples:
- Create an Empty Tuple
- Create Tuple with Homogeneous Elements
- Create Tuple with Heterogeneous Elements
- Create Tuple with Single Element
- Modify Elements of Tuple
- Accessing Elements of Tuple – From the Front
- Accessing Elements of Tuple – From the Back
- Search Within a Tuple
- Add Elements to a Tuple
- Delete an Element from a Tuple
- Iterate Over a Tuple
- Concatenation of Tuples
- Identify Length of a Tuple
- Slice a Tuple
- Count the Number of Elements in a Tuple
- Identify the Index of an Element in a Tuple
- All Tuple Examples in one Example tuples.py Program
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by Ramesh Natarajan
on March 26, 2019
In your AWS environment, for configuration management, you can use AWS OpsWorks which provides managed instances of either Chef or Puppet. You have the following three options when using AWS OpsWorks.
- AWS Opsworks for Chef Automate
- AWS OpsWorks for Puppet Enterprise
- AWS OpsWorks Stacks – This is for application modeling and management. You can model your app as a stack with different layers (e.g: web layer, db layer, etc.). This uses Chef solo in the backend to configure nodes.
This tutorial provides the following examples on how you can manage your AWS OpsWorks servers from CLI using aws opsworks-cm command.
- Create OpsWorks Server (Chef or Puppet) using create-server
- View OpsWorks Server Details using describe-servers
- Delete an OpsWorks Server using delete-server
- View Account Attributes and Server Events of a Server
- Update Server Maintenance and Backup Window using update-server
- Disable or Enable Automated Backups
- Specify Backup Retention Count
- Reset Chef Server’s Private Key (or) Update Puppet Admin Password
- Take a Backup of OpsWorks Server using backup-server
- View Available Backups using describe-backups
- Delete an OpsWorks Backup using delete-backup
- Restore OpsWorks Server from a Backup using restore-server
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