Explore topic-wise InterviewSolutions in .

Django framework has a number of significant advantages for DEVELOPMENT majority of them are

• Django provides auto-generated web admin to help developers BUILD website administration simple.
• It also provides prepackaged API which helps in general user tasks.
• Under this framework, business logic can be segmented from HTML
• It can divide the code module into simpler logical groups to make the process flexible for modifications
• In this framework, a template SYSTEM is provided for defining an HTML template to avoid code duplication.

This is most REPEATEDLY ASKED Django interview questions.

Django as a web DEVELOPMENT framework is extremely BENEFICIAL for developers to build effective web applications. Written in python it is an open-source and free web application framework which was built to deal with intensive designing. LATER it was used by the developers to build supreme quality web applications as it strictly FOLLOWS the DRY principle and only focuses on AUTOMATION.

In order to create a constant in DJANGO, we have to OPEN the settings.py FILE and then a VARIABLE has to be added into it, for example: MY_CONST = "MY_VALUE". In order to utilize it constantly in VIEWS you just have to import the settings "import settings in views.py" and use it- Settings.MY_CONST

• SAP SQL Anywhere
• IBM DB2
• Microsoft SQL Server
• Firebird
• ODBC

OFFICIALLY DJANGO SUPPORTS for DATABASE BACKENDS which are-

• PostgreSQL
• MySQL
• SQLite
• Oracle

Django was created in the YEAR 2003 when web programmers ADRIAN Holovaty and Simon Willison were USING python for APPLICATION development. Because of its popularity, it got publicly released in the year 2005 under the BSD.

Middleware is a function which transforms a USER request or response as it passes through the view layer.

Its UTILIZATION is-

• Can be USED for session management
• For user authentication
• It also HELPS in cross-site request forgery production
• Content Gzipping.

The most recommended way to install the Django FRAMEWORK in your system is by USING pip.

The follows the steps as-

• Firstly install pip
• Now configure virtualenv and virtualenvwrapper

As you have created and activated the virtual ENVIRONMENT now you have to enter the COMMAND - pip installs Django.

Iterators are mostly USED for TRAVELERS in the object in python framework implementing ITERATOR protocol.

This comprises of TWO methods which are-

• __iter__()
• next ()

To GET the URI in DJANGO TEMPLATE we will USE
{{ request.path }} then {{ request.get_full_path }}

Context refers to a DICTIONARY containing multiple variable names which are in the form of key or VALUE. When this context is passed to the temperature render METHOD the variable gets replaced with TEMPLATES.

Mixins refer to SPECIAL multiple inheritances SUPPORTED and developed by Python.

It is mainly used under two circumstances-

• When you have to provide a number of features for any class
• To utilize any ONE SPECIFIC number of DIFFERENT classes.

The Django framework is based upon MVC- MVT architecture where MVT stands for the model VIEW TEMPLATE design pattern while MVC stands for model view controller pattern.

RESTFUL APIs are extremely beneficial for WEB developers to build web applications as they consume the lowest bandwidth and their design in such a WAY to communicate well with the INTERNET mainly like PUT, POST, GET, etc.

Django Rest Framework (DRF) is an efficient framework which allows the developer to CREATE RESTful APIs QUICKLY. A number of BIG ENTERPRISES have supported its funding and the reason for its popularity is features like serialization, web browsable API and authentication policies.

As Django follows MTV ARCHITECTURE it is CALLED LOOSELY coupled framework by the developers. It is based on the architecture which is a suitable VARIANT of MVC framework and MTV is beneficial as it provides a separate server code from the third person's machine. The component in industry work is different from each other and that's why front end or backend developers work simultaneously for any tasks.

This is a majorly asked Django interview question.

DJANGO admin interface easily supports the customization and developer can DOWNLOAD various other third-party applications and install them in a completely different view. Also, if the developer wants overall control over their admin then they can make their own admin application. The admin site can also be customized for example CHANGING the PROPERTIES of admin.site.object. this admin interface also supports the changes in modifications in MODELS and to apply them in Django admin for specific applications. The Django admin interface supports customization exact from the lowest level and the developer can also create new admin interfaces.

Let's assume a USER ENTERING any of the URLs in a browser, the same request will be received on the Django server. Once the request is generated, the server will find for the match of the corresponding URL in its URL-config. If the URL matches from the request then it will return the same findings for corresponding view function. Right after the return of the URL, a request is SENT to the model of application for data. If the data is required then it will pass the corresponding template for further rendering in the browser. In case this doesn't happen then it will SHOW 404 server errors.

The Django framework of the complicated project includes a collection of a number of web applications which mutually co-ordinate to serve the user request. These applications have their own corresponding features which are REQUIRED to be completed by the same.

• Manage.py
• Settings.py
• __init___.py
• Urls.py
• Wsgi.py

This QUESTION is one of the most important Django INTERVIEW QUESTIONS.

DJANGO offers maximum code reusability to the developers as compared to other frameworks. This framework is also a collection of various applications including login APPLICATION or signup application. With the help of this framework, a LARGE number of applications can directly be copied from ONE directory to the next following some of the settings.py files. With this framework, developers can easily WORK over the application without writing the new sign up application. This is the reason which supports the rapid development framework in Django and there are no other compatible frameworks supporting this level of code reusability.

Django is actually of preloaded interface designed to fulfill the requirement of web developers. Basically, it INDICATES any requirements for the web developer to make other admin because the whole process is time-consuming and costly. Django admin interface SUPPORTS user authentication and follows most of the INCLUDED features. The application Django admin is imported from the Django.contrib package. This imported application is also expected to get control by the corresponding organization hence it does not require an ADDITIONAL front end.

The Django admin interface provides a number of ADVANCED features like-

• Authorization access
• Managing multiple models
• Content management system

Django is an EXTREME level web APPLICATION framework which is entirely BASED over python. As it is written in python, it is also an open-source web application framework which makes web application development quick and efficient. It is one of the most preferred web application development frameworks in the industry. Django also SUPPORTS less coding and it is suitable for faster development and pragmatic design.

• Admin interface
• ORM
• A large number of third party application
• Number of security features
• CDN integration
• Admin interface

• Playbook: playbook is REFERRED to as a code file that is written in YAML format. It contains the essential tasks REQUIRES to be implemented.
• TASK: Task represents a single procedure that is REQUIRED to be executed.
• Play: Play refers to a task is executed from beginning to end or EXECUTION of a playbook.

Ansible fact is a WAY for tools to get DATA and complete information about a host and store them in the variables for their easy access. This information is stored in predefined variables that are available for use in the playbook. To generate the facts and simple techniques the setup module is as-

$ Ansible- m setup hostname

As soon as the statement gets executed it will print out a list of a dictionary of the facts which are available for a particular host. This is the way to access the list of available Ansible_variables. These facts can be seen as-

$ Ansible all- m setup

If a user wants to extract any particular part of the available information then the "set up" model can be used where an option is available to filter out the output and the facts which are required can behold.

The Ansible files can be made reusable in following ways-

• Include
• Role
• Import

In order to break or create the number of smaller files of any huge playbook imports and includes are used. Rolls are used to organize and manage multiple tasks following a package including plugin, variables, handlers and other MODULES. By using Ansible galaxy they can also be uploaded and shared directly.

Ansible modules are idempotent which means it professionals can perform the task of RESTful service standpoint for idempotent OPERATIONS. In this condition various identical requests became a single request end-user can create its own modules in Ansible.

• Core modules: This type of module is managed by the Ansible TEAM and they always ship with its software. The highest priority is given to this module as compared to other modules.
• Extras modules: CURRENTLY these models are bundled with Ansible but maybe they will be AVAILABLE separately in the future. Mostly they are managed and organized by the Ansible community.

It is a standard rule to FOLLOW: always USE {{ }} except when. In order to RESOLVE the expression, conditionals are run through Jinja 2 hence when: failed_when: and changed_when: ATTEMPTED we must avoid adding {{ }}.

The web-based solution which makes Ansible an easy task for the IT professionals or teams associated with any PROJECT an easy task to OPERATE is Ansible TOWER. Ansible tower is DESIGNED to act as half for the automation tasks and it is free for its uses up to 10 nodes.

This Ansible interview question comes under the ADVANCED segment.

Ansible playbook is the actual BUILDING block supporting all of the use cases of the Ansible tool. The variety in YAML TAGS are DIVIDED into four major types which are known as-

• Declaration
• Vars
• Tasks
• Handlers

Ansible playbooks are also a combined set of commands that has the CAPABILITY to PERFORM huge tasks and they are also written in YAML file format.

Ansible tower PROVIDED by Red Hat or Ansible, both are in the N2 and automation platform which has the capability to provide a number of features.

• Provision of components
• Deploying the APPLICATIONS
• Orchestrating workflow
• Managing its SYSTEMS and infrastructure
• Configuration of systems
• Networking and other applications

By DEFAULT, Ansible has a file on /etc/Ansible/hosts containing a hostname or IP address of the TARGETED system. The inventory file can be specified with the help of -I OPTION on the command line. Ansible actively selects the segment of hosts to WORK from this inventory file. This file can be in YAML or INI format. In the inventory file host and group, variables are defined and it is easy to assign these variables to host for later utilization.

NOTE: This is one of the frequently asked Ansible interview questions.

There is a feature named Vault in Ansible which HELPS IT professionals, to keep their sensitive data in encrypted files. The passwords or keys are secured extensively rather than in the form of plaintexts in Playbooks. A command-line tool named Ansible- vault tab is present in Ansible which is USED to edit the files. Few common flexes are also used along with these command-line TOOLS as ask-vault-pass or vault-password-file. In ORDER to PROCESS the playbook containing vault encrypted files, you have to pass any of the two flags.

Let us learn about the procedures in detail:

1. It can be INSTALLED using Linux's best installation architecture.

• In order to serve the purpose first add the repository to APT by using the command on terminal 'sudo apt-add-repository -y PPA: Ansible/Ansible'
• Now update the repository by using the command 'sudo apt-get update'
• Using the command 'sudo apt-get install -y Ansible' Ansible can be installed

2. with the help of Python installer:

• First of all, install python on your local machine
• Using the command 'sudo PIP install Ansible' on terminal install Ansible.
• This can be updated with the command 'sudo pip install --upgrade Ansible'.

As soon as sensible that's installed on your system you can verify it with the help of command 'Ansible --version. This Ansible interview question has proved to be a tiebreaker in many conditions.

The major constituent of Ansible are nodes and controlling machines where Ansible is installed on controlling machine and nodes are used to manage these controlling machines with the help of SSH offering no downtime. With the help of inventory files, the controlling machine specifies the location of nodes.

Ansible also deploys modules to nodes with the help of SSH protocol and these modules get stored temporarily in remote nodes. These models can also COMMUNICATE with the Ansible machines with the help of the JSON connection over the standard output.

• It has LOW overheads and can be EXECUTED with minimal RESOURCE utilization.
• The only DEPENDENCY of Ansible is python.
• All of its tasks are written in YAML syntax.
• Ansible is extremely easy to LEARN and understand.

Using two DIFFERENT METHODS, it is easy to INSTALL Ansible.

• Install it from a DISTRIBUTION package repository.
• Build from source code.
• Install Ansible using python package management tools for example pip.

Ansible offers a number of benefits, like-

• No agent required: For the setting of the Ansible deployment tool, no specific agent is required. Also if Box has a tendency to support SSH and Python then there is no need to set up Ansible.
• Idempotent: Ansible is structured in such a way to follow the overall concept of idempotency. Its FUNDAMENTAL idea is to add only those things which are actually "required" and these things can be repeated.
• Declarative but not procedural: The majority of configuration tools follow through a complicated process of doing ONE thing then next, then next and so on. Ansible as an efficient configuration and deployment tool ALLOWS the IT professional to write the description of the STATE of the machine simply and MENTION the requirements and right after the description, it starts taking steps towards it.

Being an open-source deployment tool Ansible offers communication with configured lines initiating from the command line with the help of Ansible command. This PHENOMENON allows IT professionals to automate the configuration using any ansible-playbook command and in order to create any BASE directory structure, one has to use tool bundled with Ansible.

This structure is known as Ansible-galaxy. This is one of the most commonly asked Ansible interview questions.

Ansible is a widely-used open source IT CONFIGURATION management and deployment tool. This orchestration tool helps to provide maximum productivity gains for the majority of automation platforms also it helps in the setup and management of INFRASTRUCTURE and associated applications. Ansible is UTILIZED to manage IT infrastructure and to deploy software applications directly to remote nodes.

Chef RESOURCE defines a small SEGMENT of the operating system in its desired state. It also refers to a configuration policy statement that is utilized to represent the desired state of any node and then to the current configuration. All together it helps resource providers and developers.

• The present status of the TARGET machine can be known for its help
• it also defines the STEPS which are required to perform to get the target machines
• It also specifies the RESOURCES for example templates, services, files or packages.

CONTINUOUS monitoring HELPS the developer to DETECT and analyze the security implications to get a better view of planned or unplanned changes. Continuous monitoring also helps to assess the vulnerabilities for ERRORS that are in a space of threat. To deliver the information based on application performance and the patterns of usage it works better.

Some of the best continuous monitoring TOOLS are-

• Nagios
• Tenable
• Solarwinds
• Lansweeper
• Spiceworks
• Snorts

Containers in DevOps refers to the OPERATING systems' virtualizations. A SINGLE container can be utilized to run everything including from staging the environment into production. This also CONSISTS of the entire runtime environment for example libraries, necessary executables, configuration files, BINARY code and many more. Containers are streamlined in order to create, deploy, redeploy and test the applications in various environments.

• Reduction in the overheads.
• Improve productivity.
• Consistency with operational tasks.
• Application development is also enhanced.
• Extreme efficiency.

It is a general question asked in DevOps INTERVIEW questions.

The most common and popularly used deployment PATTERNS are Blue-Green deployment and CANARY release. In blue-green deployment, two different and identical environments are present where the green environment refers to the initial production system. Actual deployment takes place in the blue environment. It is ALSO responsible to monitor for in error fault and once everything starts WORKING fine then the load balancing and another component instantly switch the green environment to blue.

Canary RELEASES have the efficiency to roll out any specific feature to a subset for a developer. This release helps the developer to reduce the risk factor involved in the release of new features.

Trunk based development SIGNIFIES a source control branching model to organize software development. In this procedure, DEVELOPERS are engaged in code under a SINGLE branch which is known as strong and UTILIZES document techniques in order to create long-lived development execution. Trunk based development is a key enabler for a number of INTEGRATIONS.

Git refers to a distributed version control system that is used for recording the CHANGES in SOURCE code during the time of development. It ALSO monitors the set of project overtime and stores the required information in a structure called repository.

• Git config- for global username
• Git init- for the repository name
• Git clone- for clone
• Git add- to add the file

Continuous monitoring is required when the application is developed and deployed in order to check for its performance. With its help, it is possible to find the LOOPHOLES or defects which might have been missed by the team earlier. Continuous testing is utilized to MAKE the application out to REACH the end-users. Without sufficient continuous testing or unit testing and automation, it is not possible to GET the DESIRED results. To validate the code and integrate them with developers it is essentially required.

One of the core ADVANTAGES of DEVOPS automation is that it MANAGES the ROLE of human error out of the CD EQUATION.

When it comes to DEVOPS continuous delivery and continuous INTEGRATION are very important to consider and understand. Both of them are critical steps where continuous integration refers to an automated build-up that results as a generation. It is a software development PRACTICE in which members of the teams frequently line up and INTEGRATE their code which later undergoes the generation process. It is then verified carefully ALONG with the code written by the members. Each of these integrations is then verified daily and tested as a significant part of the development process.

Pair programming is an engineering practice of the WELL defined and extreme programming rules. In these, two different programmers WORK simultaneously on one computer, on the same design, algorithm, code or test. Where one PROGRAMMER acts as an "observer" while others act as a "driver", it is their shared responsibility to monitor the errors. Without any handoff, their roles can be exchanged or shifted at any point in the process.

Its significant advantage is that it helps in RAISING the theory among different points of view which can eventually help to increase our understanding of the same CONCEPT considering the code, algorithm or design.

Git is basically a source code MANAGEMENT tool that can handle multiple projects with efficiency and perfection. It is utilized to store the repositories for remote servers.

It is almost ALWAYS asked in the DevOps interview QUESTIONS.

The most recognizable adoption of DevOps seen in the industry involves the utilization of agile and various developmental processes and METHODOLOGIES. It also involves the demand for an INCREASE in production release from a business POINT of view. Its other adoptions involve-

• Large AVAILABILITY of cloud infrastructure for external as well as INTERNAL providers
• increase in data center configuration management tools
• Improvisation in automation
• Increased focus on test automation and continuous integration process
• Enhanced practices over critical issues