Thread by @developer_ram

Learning Azure this thread will curate my learning for Az 204. Lets start

We can test the availability of application using the application insights. the famous tool is url ping test. This test check for performance of each request and the response

They also add the ability to set custom success criteria, coupled with more advanced features like parsing dependent requests and allowing for retries

The URL can be any webpage that you want to test, but it must be visible from the public internet

Parse dependent requests- The test requests images, scripts, style files, and other files that are part of the webpage's under test

The test might fail for cases that aren't noticeable from manually browsing through the site

If your URL isn't visible from the public internet, you can choose to selectively open your firewall to allow only the test transactions through.

Microsoft Graph is a RESTful web API that enables you to access Microsoft Cloud service resources

conditional access policies belongs to AAD where we can define who to access the application.

graph.microsoft.com/v1.0/$metadata

The metadata allows you to see and understand the Microsoft Graph data model, including the entity types, complex types, and enumerations that make up the resources represented in the request and response packets

GET graph.microsoft.com/v1.0/users HTTP/1.1

we can get user information from the above call. Each user is found through the id.

Microsoft Graph also lets you view collections by navigating the relationships of one resource with another

Microsoft Rest Api format

Microsoft graph has a concept called batching where multiple requests are joined together using json

microsoft implements oauth 2.0 identity platform. In oAuth 2.0 there permissions are given through scopes.

There are two types of permission:
1. Delegated permission - where a user is signed in and the user will allow the permission to access another resource / application.

2. Application permission - It happens in the background without permission from the user only admin permission is needed.

Azure logic app - Integrated sevice environment : it defines an Integration Service Environment (ISE) as a private and isolated Logic Apps instance within your Azure virtual network

serverless360.com/blog/azure-log…

ISE in logic apps provides alternative approach on cost model where they can have dedicated pricing vs consumption pricing.

Headless authentication means without having popup on login where user can access without provide password.

Azure CDN edge nodes will cache assets until the asset's time-to-live (TTL) expires. After the asset's TTL expires, when a client requests the asset from the edge node, the edge node will retrieve a new updated copy of the asset to serve the client req and store refresh the cache

Note that purging only clears the cached content on the CDN edge servers. Any downstream caches, such as proxy servers and local browser caches, may still hold a cached copy of the file. It's important to remember this when you set a file's time-to-live

Assets to purge the data.

There are three types of event :
Discrete - It provides information about state changes and getting this event we can do an actionable usecase.(Event Grid)

Series - It provides information about time series which can be actionable insights. time ordered and analysable insights.

user notification - where notification is sent to the

event signals something has been changed. publisher has no role in event just get the data and send it to subscriber.

To enable a cdn for web app, Create a new cdn profile. there is a cdn endpoint which will be asked for enabling at the start of creating cdn.

A cdn endpoint connect our web app to cdn. we need to provide origin type from which our cdn get the data it can be anything from storage account, cosmos db or webapp.

Once the propogation of content is moved from web app to cdn then all the request will go to cdn. not to the application.

cdn reduces hosting bandwidth. two types of content in web static and dynamic. In cdn the users get the static content from point of presence nearest cdn region.

THree caching rules:
1. Global
2. Custom caching rules - For example if you want specify cache rules for particular type of file like js.
3. Query string caching - a key value pair caching mechanism default thing is ignore query string. we can also bypass query string.

We can define caching rules if it contains query string then we can bypass them. we should not use the cache rules "cache every unique url" if the url change for each request.

We can set custom rules for particular file extension or particular path.

In redis once u scaled up the princing tier from basic to premium we cannot scale down.

In redis it seems there is no expiration date. it will be cleared when it;s removed.

Calculating cache duration : How to calculate the ideal time to set cache expiration. They are based on following:
1. Rate of change.
2. Risk of Outdated Data.

Redis Cache best practices:
1. set expiry time
2. Avoid caching large object - if there is a large object then divide it into small objects.
3. Hosts redis in the same region

Implementing Application caching patterns:
1. Cache aside pattern :
2. Content cache pattern :
3. User session cache pattern : Maintain cache state

Configuring redis cache :
Estimating Cache size :
1. no of concurrent cached objects
2. size of cached objects
3. no of cache requests
4. Cache expiration policy - consider expiry time

Redis benchmarking is the tool which simulates the connection to check whether the redis scale is correctly happening or not. Testing mechanism provided by redis.

Securing redis cache : Encryption at transit.

Cosmos Db:
1. No sql databases.
2. Provides BASE distributed system
3. It has automatic indexing.

#100daysgoals #Day4
1. create a account
2. Create a DB.
3. Create a container.
4. Create items

SQL Api is the default when we are working with cosmos.

1. az cosmosdb create --name xxx --resourcegroup yyy
2. az cosmosdb sql database create --account-name ddd --name sampledb
3. create the container with partition key path
In sql api we create container not table only in cassandra and azure tables we create tables inside the db.

use a partition key to even spread throughput on partitions.
provision throughput at the container for predictable perfromance.

strong consistency - when we do select we will get the most recent data

Bounded staleness - we will get the latest data but the catch is there will be delay in terms of version or in terms of time.

session consistency - for the given client when a client makes the write and the same client do the read then for that case we provide the latest data in the db.

consistent prefix - we will get the data in the same order in which the writes / updates or done.

eventual consistency - we will get the data in some time in future but we dont know when and we are not sure of the order of data. we can use this when order of data is not an issue like blog post.

cosmos db partition - logical partition, physical partition, partition key , replica set.

a logical pattern is a set of items in the container that share the same partition key. logical partitions are managed by cosmos.

A partition key decides where to route to get the correct data.

Microsoft identity uses openid connect for authorization and oauth 2.0 for authentication.

important ad manifest file :

approles
group memeberclaims
optional claims
auth2allow implicit flow
oauth2permissions
signinaudience

approles - it specifies the collection of roles that an app may declare.

groupmemberclaims- configures the groups claims issued in user or auth2.0 access token that the app expects.

Cosmosdb SDk uses :
CloudStorageAccount - retrieve storage account information from connection string.
CloudTableClient - Create a table client for interacting with the table service
CloudTable

Change Feed processor: It simplifies the process of reading the change feed and distribute the event processing across multiple consumers effectively.

There are four components of change feed processor :
Monitored Container - it has the data from which the change feed is generated.

The lease container acts as a state storage and coordinates processing the change feed across multiple workers. it gets the data of the all the workers who works.

Hosts : it will check for any changes in the change feed processor.

The delegate is the action part. it's the developer who decides what to do with the batch of the data generated by the change feed processor.

for registering new application with active directory follow the below steps
1. select the active directory instance.
2. select register the application
3. create the application by providing name, url etc

To enable multi factor authentication in azure active directory we need to upgrade the account to premium.

Cosmos db operator can do all the things with respect to the account but they can't access the data. so they will not have access for the keys to which they can access the data.

stackoverflow.com/questions/4934… the best place to store images are blob storage not cosmos db.

In vm encryption there is a property called volume type which enables us to encrypt both the Operating system and Data in it.

Durable Functions enables you to implement complex stateful functions in a serverless-environment.

Azure Functions operate in a stateless environment, Durable Functions can retain state between function calls

Durable functions allows you to define stateful workflows using an orchestration function

Azure may choose to dehydrate the function and save its state while the function waits and it will rehydrate and restore its state.

durable function types: Client, Orchestrator, and Activity

Durable Functions and Logic Apps are both Azure services that enable serverless workload. Azure Durable Functions is intended as a powerful serverless compute option to run custom logic. Azure Logic Apps is better suited for integrating Azure services and components

azcopy sync- Replicates the source location to the destination location

@UnrollHelper