I was recently helping a company to work through a set of white hat penetration test results for a legacy web application. Among other things, was a note that while the web application did support TLS 1.2, it was still accepting connections via TLS 1.0/1.1. As to why this is a security risk, here is a great article on the subject from Digicert : https://www.digicert.com/blog/depreciating-tls-1-0-and-1-1. But in short, most modern web applications should only accept TLS 1.2, and should actually reject TLS 1.1 and 1.0.

Luckily this is a fairly trivial fix if we are using Azure App Services with no (or minimal) code changes!

Setting The Minimum TLS Version Via Portal

If we are looking to set the minimum TLS version via the portal, we first have to open up our App Service, and look down the left hand menu for TLS/SSL settings.

On this screen we can edit the TLS minimum version, which should really be 1.2 at all times.

And we are done! A very easy setting to change that adds a tonne of security benefits.

Setting The Minimum TLS Version Via ARM Template

While editing this setting via the portal is great, chances are you have an ARM template that you use to automate your deployments.

While it’s hard to show the full ARM template here as it’s rather verbose, inside your template you likely already have a Microsoft.Web/sites/config element, and inside that properties. Adding a minTlsVersion property will allow you to set the minimum TLS version of your web application.

{
	"type": "Microsoft.Web/sites/config",
	"name": "myAppServiceName/web",
	"apiVersion": "2018-11-01",
	[...]
	"properties": {
		[...]
		"minTlsVersion": "1.2",
	}
}

Default TLS Version

It’s important to note that this is mostly a legacy issue. If you create a fresh Azure App Service anytime beyond June 2018, the default minimum TLS version is automatically set to 1.2. However existing App Services are left unchanged and so you may have to do a quick work around of all existing services and upgrade them.

Additionally, if you for whatever reason did need to support TLS 1.0 (Which you really really shouldn’t!), then you would need to downgrade this setting on any new services created.

I’ve recently been reviewing content and training material to help both technical and non-technical people alike pass their AZ-900 Azure Fundamentals exam. The official exam description is :

The exam is intended for candidates who are just beginning to work with cloud-based solutions and services or are new to Azure.

And :

Azure Fundamentals exam is an opportunity to prove knowledge of cloud concepts, Azure services, Azure workloads, security and privacy in Azure, as well as Azure pricing and support. Candidates should be familiar with the general technology concepts, including concepts of networking, storage, compute, application support, and application development.

But what I really found was that the AZ-900 exam is all about your general fundamental knowledge of cloud in general, and a couple of services that you will almost always be using no matter which cloud set up you go for.

As an example, you should have a broad base of knowledge on cloud computing to answer questions like “What is a hybrid cloud model?” or “What is the difference between SAAS, PAAS and IAAS”, but also still be able to handle left field questions such as “What are Azure Availability Zones?” or “Which feature of Azure Active Directory will require users to have their mobile phone in order to be able to log in?”.

Essentially, it’s a very broad intro to Azure for anyone to get the gist of what cloud computing is about, and some general Azure terms and concepts. If you are using Azure in *any* capacity, whether it be sales, software development, infrastructure, security engineer, even a business analyst, it’s a worthwhile exam to take.

Exam Courses / Guides For AZ-900

There’s really only two main source of material for the AZ-900 that I recommend.

The first is actually the official Microsoft learning pathways for Azure Fundamentals.

It’s fairly verbose but it’s extremely content rich. In total, you are looking at 15 and a half hours worth of videos and reading material to get you prepared for the exam. Personally, I think it’s a bit overkill and if you have a bit of experience with Azure and Cloud already, it may be a bit of a slog to get through all 15 hours. But on the flip side, you’re going to be getting a real in-depth look at all things Azure and basically not have to go anywhere else for exam prep. And, it’s free, so no complaints there.

My second recommendation is Scott Duffy’s AZ-900 Microsoft Azure Fundamentals Exam Prep video course available on Udemy.

This course is a much more concise and chopped down version clocking in at just over 5 hours. It also comes with a 50 question practice test, and you can download the audio if you’re on the go as well. There is a cost associated with the course, but like everything on Udemy, you can usually pick it up on sale for $12 bucks or so. It’s had 125k+ students through the door so it must be doing something right! The other benefit is that if you use Scott Duffy for other Microsoft Exam Prep, he often sends out discount counts to get his other courses. So if you are interested in say the Scott Duffy course for the Azure Architecture exam, you can start with him with the fundamentals and use him all the way through your learning path.

Practice Exams For AZ-900

Microsoft actually offer a paid practice exam through Mindhub. The only issue is, the practice exam is (depending on your currency) more than the actual exam itself. While the actual exam may cost somewhere in the vicinity of $99USD, the practice exam for a 60 day period is $109USD. In my view, it’s just not worth it. Specifically for the AZ-900 exam, you really don’t need to be cramming for it. It really is a fundamental exam and so spending a tonne of money on practice questions just isn’t needed.

Again, Scott Duffy also has an AZ-900 practice exam on Udemy. This is much more reasonably priced, and usually you can get a bundle deal if you buy the course with the practice questions. I think some people have a worry that buying a third party practice exam won’t be close to the real thing, but if anything, I found people complaining a lot more about the MindHub practice exams than any others. The thing is as well, you can usually get these for around $10, and it comes with 150 practice questions. Overall, these should point you in the right direction of where you need to study more, and for very little cost.

Areas For Free Points

Any time I do an exam, I look for areas that are very easy to memorize, and yet will always come up in the exam. Many many years ago, I remember doing the CompTIA A+ exam which involves memorizing a set of 15 IRQ numbers and their corresponding devices. Just a list of 15 numbers. And every single exam there was atleast 2 questions asking “What IRQ is number 2” for example.

So with that in mind, when I was looking at AZ-900 and doing practice exams, I looked for areas where I knew I could easily memorize and learn the answer for, but were an almost certainty to come up in the exam :

  • Learn about availability sets, regions, update domains, fault domains, and in general know how Azure offers high availability.
  • Know the different levels of feature release (Private preview, Public Preview, General Availability) and their relevant SLAs.
  • Understand how Microsoft offers support and when.
  • Understand the benefits of cloud hosting in general. There is almost always a question about cloud computing being “elastic” or questions about scaling
  • Understand the different network security offerings in Azure, for example Firewall, DDOS Protection, NSG etc and when you would use them
  • Try and understand when you would use Cosmos, Data Lake, SQL Data Warehouse, Azure SQL, Blob Storage or any other storage mechanism that comes up, almost certainly you will be asked something about which is the right data storage mechanism
  • 100% know the difference between hot and cold storage in Azure Blob, you will always be asked something about this.
  • Read a bit on Azure AD. It’s kind of a broad topic but in general as long as you understand what it does, and what it can offer (For example MFA), you should be good.

Overall, the exam is honestly pretty straight forward. There are always curly ones like “What is the maximum amount of VM’s allowed in a scale set”, but overall from the list above, you will get one or two in each of those areas. For example, simply memorizing the difference between hot and cold storage in Azure Blob Storage now gets you an extra mark for about 10 minutes of reading.

Braindumps For AZ-900

I don’t think it would be a tips post for a Microsoft Exam without mentioning the infamous brain dumps. So let’s get this out of the way early. Braindumps are just cheating the exam in a different way. If you’ve never heard of braindumps, it’s essentially buying the questions for the real exam, and studying to be able to answer those specific questions only.

Yes you can use TestKing. Yes you can use Pass4Sure. But let me just say this. If you need braindumps to pass AZ-900, just find a different job. It will be easier that way.

You honestly should not need a braindump for any fundamentals course. I know some people try and justify using exam dumps sometimes by saying that the exam questions are worded poorly. Or the training material is garbage and there is no way you could pass the exam without a braindump. But AZ-900 is not that. It’s a very straight forward simple exam that as long as you do any amount of study, or have been working in IT using Azure (Or any cloud) for any length of time, you can pass. You do not need braindumps for this exam.

This is going to be a nice short and sweet article, but one that I’ve felt the need to write for a while.

Many times when I’ve built small internal applications, hosted in Azure, there has been a need for some level of authentication. Pretty often, this is going to be against the clients Azure AD instance. I’ve seen people wrap themselves up in knots trying to use the “Microsoft Authentication Library (MSAL)” inside their code. Often this comes with many code changes, configuration, and banging your head along the way.

Sometimes that headache is unavoidable, but other times for your simple 5 page website, it’s just way overkill.

Did you know that you can set up Azure Authentication across a web application, from inside the Azure Portal, without any code changes what so ever? It’s really simple! Simply navigate to your Azure App Service and select “Authentication” under settings on the left hand menu

Next add an identity provider, as noted in the screenshot below, this can be Microsoft (Active Directory), Facebook, Google or Twitter.

The settings are fairly explanatory and work much like how you would set up app registrations within Active Directory normally (But this time it’s mostly done for you).

Once added, any access to your application will be forced to authenticate with your chosen identity provider.

Now you’re probably asking, what if I want to limit access to certain groups or users? Unfortunately Azure App Service only provides an “Authentication” service, it does not provide an “Authorization” service. So even though it can force users to login, it simply passes those claims through to your application to then validate if a user should or should not be able to access that page.

What this means in practice is that if you need complicated set up of roles and permissions.. Maybe the built in Authentication with Azure App Service isn’t right for you (Although it is definitely doable) as it somewhat disconnects the authentication and authorization pieces. However, what I’ve found is for small internal applications that we simply want to say “Anyone in an org can use, but not the public”, then this is a great little way of achieving that with zero code changes.

Apologies for the absolute word soup of a title above, but I wasn’t sure how else to describe it! So instead, let me explain the problem I’ve been trying to solve lately.

Like many organizations using Azure Devops, we are slowly switching our pipelines to use YAML instead of the GUI editor. As part of this, I’ve been investigating the best way to conditionally deploy our CI build to environments. Notably, I want our CI build to run for every check in, on every branch, but only move to the “release” stage if we are building the develop branch and/or the main trunk. As we’ll find out later, there also needs to be an override mechanism for this because while it’s a general rule, it’s also something that may need to be flexed at times.

YAML pipelines documentation can be a bit shaky at times, so most of this came from trial and error, but here’s what I found to solve the problem of conditionally deploying Azure Pipelines based on a branch.

Using Environments

Your first option is to use Environments inside Azure Devops. You can add an “Approval and Check” to an environment, and then select Branch Control.

You can then specify a comma seperated list of branches that are allowed to pass this environment gate, and be deployed to the environment :

But here’s the problem I had with this approach. Environment gates such as the above are not in source control. Meaning that it’s hard to roll out across multiple projects at once (Compared to copy and pasting a YAML file). Now that’s a small issue, but the next one is a big one for me.

These checks based on a branch actually *fail* the build, they don’t “skip” it. So for example, if a branch does not match the correct pattern, you will see this :

This can be incredibly frustrating on some screens because it’s unclear whether your build/release pipeline actually failed, or it just failed the “check”. There is also no way to override this check on an adhoc basis. Maybe that’s something you desire, but there are rare cases where I actually need to deploy a feature branch to an environment to test something, and going through the GUI to disable branch control, release, then add it back just doesn’t make sense.

Using Pipeline Variables

A more explicit way I found to control this was to use variables inside the YAML itself. For example, every project of mine currently has the following variables utilized :

variables:
  isPullRequest: $[eq(variables['Build.Reason'], 'PullRequest')]
  isDevelopment: $[eq(variables['Build.SourceBranch'], 'refs/heads/develop')]

Now anywhere in my pipeline, I can use either variables.isPullRequest or variables.isDevelopment and make conditional deployments based on these. For example, I can edit my YAML to read like so for releasing to my development environment :

- stage: Development
  condition: and(succeeded(), eq(variables.isDevelopment, true))

This basically says, the previous steps must have succeeded *and* we must be using the development branch. When these conditions are not met, instead of a failure we see :

This is so much nicer than a failure and actually makes more sense given the context we are adding these gates. I don’t want the CI build to “fail”, I just want it to skip being released.

Adding Overrides

Remember how earlier I said that on occasion, we may want to deploy a feature branch even though it’s not in develop? Well we can actually add an override variable that when set, will push through the release.

First we must go to our YAML pipeline in Azure Devops, and edit it. Up the top right, you should see a button labelled Variables. Click it and add a new variable called “forceRelease” like so :

Unfortunately, we have to do this via the GUI for every build we wish to add this variable. At this time, there is no way to add it in the YAML and have Azure Devops recognize it (But there is hope for the future!).

In our YAML, we don’t need to declare the variable ourselves, instead it’s just available for use immediately. We can just modify our Development stage to look like so :

- stage: Development
  condition: and(succeeded(), or(eq(variables.isDevelopment, true), eq(variables.forceRelease, 'true')))

Now we are saying, if the branch is development or the variable forceRelease is set to true, then push through the release. If we try and kick off a build, we can now set the runtime variable at build time to push things through, no matter the branch.

Back in the day, Microsoft SQL Server Tuning Wizard along with the SQL Server Profiler was the best way to track performance of SQL queries. In production, you might even add in custom perfmon metrics to the mix. But these days, Azure SQL has you covered with an extremely powerful query performance insights tool that does all of the heavy lifting for you.

Accessing Query Performance Insights

On an Azure SQL Database, simply access the Query Performance Insight tool under the Intelligent Performance sub-heading. Note that this is at the database level, not the server level. While some metrics (Such as DTU/CPU) can be tracked at the server level, when looking at individual queries, we have to look at each database individually.

From here, we can access :

  • Resource Consuming Queries – These are queries that cost the most resource (CPU, Data) as a *sum* of all queries. That means even if a query is performant, but is executed often, it may appear in this list.
  • Long Running Queries – These are queries that take the most time to execute, but again are the *sum* of all queries. So even if a query returns fast, if it’s called often, it will appear in this list.
  • Custom – This is where we can create custom reports to better drill down into poorly performing SQL queries. This is generally our best bet at finding bad queries.

Selecting any query allows you to view the actual query text :

As well as the average CPU, Data, Duration and execution count over the time period :

Importantly, there is also a chart below which allows you to track during hour intervals the same metrics. This can help you pinpoint certain times of day that may be more problematic for certian SQL queries :

Overall, utilizing this data can go a long way to giving you very simple metrics to act upon, all with very digestible queries, charts, and graphs.

The thing to note with all of these graphs, is that there isn’t one single metric that will be able to tell you the exact performance issues with your application. For example, a SQL query may run 100 times across 100 different users in your application, but is only non-performant on a single user (Maybe they have far more data than all the others). If you look at the average of all of these queries, it may look perfectly fine, whereas sorting by “max” may pinpoint that at times, this query is non performant.

Custom Queries To Utilize

Earlier, we talked a little bit about how using Custom queries were the best way to diagnose performance issues. Here’s some of the queries that I utilize to better understand the performance of my Azure SQL Databases, and what I’m looking for when running them.

Execution Count Metrics

I utilize the Execution Count metric to understand if there are additional caching needs for my application. A good example is if every page load requires you to return how many “unread notifications” a user has in your system. Or maybe every page load, we check the current logged in user in the database.

For the former (notifications), maybe we can cache this value so we don’t hit the database so often for something that isn’t *too* important. For example, if a user gets a notification, does their notification count really need to increase in real time, or is it OK to be cached every 30 seconds?

For the latter, sometimes there isn’t anything you can do. Checking whether someone’s JWT/Authentication Cookie corresponds with a valid user in the database is probably unavoidable.

But what I try to look for is outliers and things that really don’t need to happening in real time.

Duration/CPU Average

I utilize both CPU and Duration average to find queries that have the slowest average time of executing. But we need to be careful here, because sometimes the queries in these reports truly are slow, but are unavoidable. A good example might be generating an admin report that happens once per week. Sure, we could offload this to something better at number crunching, but if it’s getting ran once a week, it’s probably not a big issue.

The real gold finds are when we can take a query that appears on the slowest average duration and on the execution count report. This means not only is it one of the slowest queries overall, but it’s also getting executed often. Sometimes the “sum” query aggregation can help you here, but not always, so I often run the two independently.

Duration/CPU Max

Finally, I utilize the Duration and CPU max to find outliers in queries that may not on average be slow, but are slow under certain conditions. Often these can be a bit of a guess. When looking at a query within the Azure Portal, you won’t be able to see the query parameters. Therefore you can’t always know the exact conditions that caused the query to slow down, but often you can start making educated guesses, and from there do test scenarios locally.

Really, what you look for out of queries from this panel are queries you wouldn’t expect to be slow, but could under certain conditions be loading a lot of data. A good example might be a user on an ecommerce site who buys things regularly. They may have hundreds or even thousands of “orders” attached to their user, but the average user may only have a couple. Here we may see the query show up here due to the max duration being extremely long for that one customer, but not show up on the average report.

Azure SQL Performance Recommendations

Spend any time using Azure SQL and you’re going to run across it’s own “Performance recommendations” engine. These are performance recommendations (generally indexes), that Azure recommends periodically to improve your applications performance. Personally, I don’t utilize them that much, and here’s why :

  • Generally speaking, Azure Performance Recommendations mostly end up recommending you create indexes. While this can be helpful, for the most part if you are watching your slow running queries using the Query Performance Insights tool, you’re going to find them yourself anyway and probably have a better understanding of the actual issue.
  • The recommendation engine also can update your database behind the scenes without you having to lift a finger. This is bad. In most scenarios, you’re going to want to add that missing index in your own source control. It’s very rare that I accept a chance via this performance recommendation engine, and let Azure implement it for me.
  • The performance recommendations don’t take into business logic, or domain knowledge into account. There may be specific reasons why queries are acceptably slow, and/or it may only be slow in some use cases which you are happy with.

In general, I think that the performance recommendations are a helpful tool for any developer, but maybe not as automated as it appears on the surface. Generally, I’ve had to go away and validate it’s findings and then implement the changes myself rather than the one click tool.

I recently ran into an issue where I wanted to test out a couple of the new pieces of functionality that Microsoft Teams apps can do (Notably, things around creating custom tabs within Teams). To test this out, I figured the easiest way would be to create a free teams account under my personal Microsoft account (So, not using Office 365), so I could play around with various test applications. What I found was that it is extremely hard to follow any guide to upload custom sideloaded apps to a free teams account, but it is possible!

If you want to skip right to the end to “What does work”, then I will forgive you, however first I want to outlay what exactly doesn’t work, and why this took me so long to figure out!

What Doesn’t Work

When guides out there (including Microsoft’s own documentation) describe uploading custom apps to Microsoft Teams, they talk about using the custom app “App Studio”. This is essentially an app, within Teams, that allows you to upload your own custom apps. That’s maybe a bit confusing, but in simple terms, it allows you to build a manifest file, upload logos, set privacy page URL’s all within a WYSIWYG editor, instead of editing JSON manually.

Once you’ve filled out all options, you’ll hit this step to start distributing your application.

The first option you are going to try is “Install”. Makes sense to try and install it for testing right? Then you’re probably likely to get this :

Or in text form :

Permissions needed. Ask your IT admin to add XYZ to this team.

Interestingly.. I am the IT admin since I created this teams account. This will lead you on a wild goose chase, notably to find either the “Teams Admin Center” or the “Office 365 Enterprise Admin Portal”. The problem is.. You aren’t an Office 365 customer. If you follow any of these links you find on the web to enable side loading applications, you’ll pretty often get the following.

You can’t sign in here with a personal account. Use your work or school account instead.

Very. Very. Frustrating.

Knowing that I couldn’t get around this limitation. Instead I decided to select the option to “Publish” from this same screen within App Studio. It looked promising until I got to a screen that said my “IT Admin would review my application and approve it”. Well.. I’m the IT admin so I guess I should receive an email soon with a nice link to approve everything? Nope! Nothing.

Doing this seems to just send it out into the ether. I never saw any link, option, or email to approve this app. Another dead end.

What Did Work

Finally, I saw another poor soul with the same issue and the usual unhelpful advice of logging into your non-existent Office 365 admin account. Then someone left a nothing comment.

You can still just upload the custom app normally.

What did “normally” mean in this context? Well I went back to App Studio and this time around selected the option to download my app to a zip.

Then at the very bottom of the Apps screen inside Teams, I selected the option to “Upload a customised app” (Note, *not* “Submit to app catalogue”).

And by magic, after a long wait of the screen doing nothing, it worked!

So what’s going on here? At a guess. I have a feeling that Free Teams Accounts have the option to sideload apps into the account, but they have other restrictions that cause the “App Studio” to report that the IT Admin will need to enable settings. It’s essentially bombing out and blaming a setting that it shouldn’t!

But there you have it. If you need to sideload custom apps into Free Teams, you *can* do it, you just can’t do it via App Studio.

For a long time now, Azure QnA Maker has been a staple of any Microsoft Bot Framework integration. At it’s simplest, QnA Maker is an extremely easy to use key/value pair knowledgebase. Where an incoming chat is best matched with a question inside QnA and that answer returned. Unfortunately, it’s rather basic and for a while has been relegated to only answering questions in a one question to one answer fashion. Essentially, QnA Maker lacked the ability to “follow up” questions to better drill down to an answer.

As an example, imagine the following question and answer.

Question : Where can I park?

Answer : If you are in Seattle, then you have to park around the back of the building using code 1234. If you are on the San Francisco campus, then unfortunately you will have to park on the street. Usually there are parks available on Smith Street. 

While we have answered the user’s question, we had to combine two different answers, one for parking in Seattle, the other for San Francisco. Maybe we add another campus, or we want to elaborate further on a particular location, things can get confusing for the user fast. It would be much better if a user asks where they can park, the first response is asking where they are located.

Thankfully, QnA Maker have recently released “Follow Up Prompts” which allows a bot to have a “Multi-Turn” conversation to better drill down an answer. There are a couple of gotcha’s with the interface at the moment, but for the most part it’s rather simple. Let’s take our example from above and see how it works.

Adding Follow Up Prompts To QnA Maker

The first thing we need to do is head to our KB Editor at https://www.qnamaker.ai/. This interface is generally fine as-is, but this time around we actually want to add one additional column. Select View options and select “Show Context”. This won’t immediately be evident what this does, but is super important as we add Follow Up Prompts.

Next, I’ll add the question “Where can I park?” like so :

Notice how our “answer” is actually the follow up question. Also notice that “Add follow-up prompt”. Clicking it, we need to fill out the the resulting popup like so :

The options are as follows :

Display Text is what our follow up button text will show. In our case, because our drill down question is asking the user which campus they are located at, we want to display a simple option of “Seattle”.

Link to QnA will actually be the initial answer. So we can fill this out as to how it will be answered if a user selects Seattle.

Importantly, we select “Context-Only” as this enforces that the only way someone can reach this, is by following the prompts from parking. Otherwise, a user can simply type “Seattle” even without first asking about parking.

After hitting save, because earlier we turned on the option to “Show context”, we will be shown a tree view of our conversation flow :

Let’s Save and Train, then Test.

Perfect! And if we ask “Seattle” out of the blue, we also see that it doesn’t return our parking answer out of the blue!

We can of course go back and add other options to the original question as often as we want.

Linking Existing QnA

One final thing I want to mention is that if you have QnA options that are somewhat close to each other, and you want to link between them, you can now also use Follow Up Prompts to do this. Most notably, I created a QnA answer to handle bad answers. I then can add it as a follow up question by typing the start of the question “Bad Answer”, and selecting the existing QnA question.

Obviously this is a great way to have a common method for handling bad answers, but you can also use this as a way to show “Related” QnA within the QnA Maker, and not have to handle conversation flow within your bot at all!

For some time now, Azure Cognitive Services has offered a “Text Analytics” feature, which can be used for finding topics within a piece of text, or even sentiment analysis to see if the overall sentiment of the text was positive or negative.

In early 2020, Azure released an additional feature to this API called “Opinion Mining”. Opinion mining is almost the cross between topic discovery and sentiment analysis. Instead of finding the overall sentiment of a piece of text, instead it finds the sentiment of individual topics. For example, in a piece of text such as :

The food here was terrible!

We would expect it to understand that not only is this a negative sentence, but specifically, we are talking negatively about the food. Being able to understand not just whether something is overall positive or negative, but also what is being talked about in that light can be invaluable in machine learning scenarios.

So let’s jump right in!

Setting Up Azure Cognitive Services For Testing

For the purposes of this article, we’re not going to get into individual SDK’s for Python, C#, Java, or any other language (Although these are available). Instead, we’re just going to use a simple Postman example of calling the API, with our key as a header, and retrieving results. This should be enough for us to see how the API works, and what sort of results we can get from it.

The first thing we need to do is head to our Cognitive Services account in the Azure Portal (Or go ahead and make one if you need to, the first 5000 requests are free so there is no immediate cost to creating the account!).

Under Keys and Endpoint, copy out your endpoint and one of your keys from this screen :

For our test, we are going to call a POST URL in the format of :

https://ABC.cognitiveservices.azure.com/text/analytics/v3.1-preview.3/sentiment?opinionmining=true

Where ABC is replaced with your cognitive endpoint taken from the above screenshot.

Additionally, we will sending a header of “Ocp-Apim-Subscription-Key” which will be our key, again taken from the screenshot above. In Postman it will end up looking like so :

The body of our request will always look like the following :

{
  "documents": [
  {
    "language": "en",
    "id": "1",
    "text": "Horrible location as it's right next to a construction site. But the food was amazing! Really friendly waiter too!"
  }]
}

Documents is actually an array because you can send multiple documents at once to the API to have them all mined at once. You still pay per document, so it isn’t a cost saver, but sending multiple documents at once can save time over sending them one by one.

Now we’re all set up, let’s get mining!

Testing Opinion Mining Out

First let’s try out a typical restaurant review :

Horrible location as it’s right next to a construction site. But the food was amazing! Really friendly waiter too!

So what we are looking for here is that it identifies that the location is negative, but that the food and waiter were positive. And what do you know (Note that the full API response is much more verbose, I’m just cutting it down to see what we need!)

{
  "sentiment": "negative",
  "confidenceScores": {
    "positive": 0.0,
    "negative": 1.0
  },
  "text": "location"
}
{
  "sentiment": "positive",
  "confidenceScores": {
    "positive": 1.0,
    "negative": 0.0
  },
  "text": "food"
}, 
{
  "sentiment": "positive",
  "confidenceScores": {
    "positive": 1.0,
    "negative": 0.0
  },
  "text": "waiter"
}

So as we can see it’s actually identified the noun that we are trying to describe, and whether our opinion was positive or negative.

Let’s try something slightly harder. What I noticed was that the opinion mining spotted the adjectives of “Horrible” and “Amazing” which should be fairly easy to spot. But how about this sentence :

I felt the food was bland. The music was also very loud so we couldn’t hear anything anyone said.

So again we are leaving a review, but specifically we are saying that the food is “bland” and the music was “loud”. There’s are very specific to the sentence and aren’t common adjectives you might use to describe something. But again :

{
  "sentiment": "negative",
  "confidenceScores": {
    "positive": 0.01,
    "negative": 0.99
  },
  "text": "food"
}
{
  "sentiment": "negative",
  "confidenceScores": {
    "positive": 0.04,
    "negative": 0.96
  },
  "text": "music"
}

And more importantly we see that it even picked up that the food being bland and the music being loud is why the opinion is negative.

"opinions": [
  {
    "sentiment": "negative",
    "confidenceScores": {
      "positive": 0.01,
      "negative": 0.99
    },
    "text": "bland",
  }
]

Really impressive stuff! Does that mean it always gets it right? Absolutely not. Using sentences with colloquial terms (For example, “The food here is the bees knees!”) just returns neutral scores, but for out of the box opinion mining with no training required at all (And very little developer legwork), opinion mining with Azure Cognitive Services is pretty impressive!

A very common query I get when storing files in Azure Cloud, is “Why are we using Blob Storage instead of File Storage. After all, aren’t we storing files?”. And it’s actually a pretty good question. And luckily, it has a very simple answer.

When To Use Azure File Storage

Azure File Storage is specifically used when storing files to be used like a managed file share. For example, if you are currently using a network share within your company on an old PC sitting under someone’s desk, you can move these files to the cloud using Azure File Storage, and have it act exactly the same as your current networked file share. Importantly, it supports both “Server Message Block (SMB)” and “Network File System (NFS)” protocols, so can be used across Windows, Mac and Linux operating systems.

While a company wide network share is obviously a good use case, another very common example is when you have an existing application (Such as a Windows Service) that you simply lift and shift onto a VM in Azure. If this application requires the use of a network share, instead of having to create a tunnel back into your office network, you can lift and shift the network share into Azure File Storage. Meaning minimal code rewrites, and making it a true lift and shift approach.

When To Use Azure Blob Storage

Azure Blob Storage is best used when storing unstructured or binary data in the cloud, and you don’t need access to it via Windows Explorer or other SMB protocols. Realistically, this means if you are storing files for your application, that are then read back via that same application, Azure Blob Storage will suffice.

It should be noted that there are Windows applications and addons that will make a blob storage account act like a file share, but it’s not recommended as some features that are available on Azure File Storage are not available on Blob and vice versa. If your main use case for moving files into Azure is to have them act as a network file share, you should use Azure File Storage instead of Blob.

File vs Blob Pricing

The other very important thing to note is that there are pricing differences between Azure File Storage and Azure Blob Storage. Sometimes it can be in the cents per GB, but often the transaction costs are vastly different on the File Storage side. For example write operations will cost you 30% more on Azure File Storage.

While it does pay to check pricing, your use case should dictate which option you go for rather than any cost difference.

While many things in Azure have straight forward “Spin this up, pay this per hour” type pricing models, Azure SQL is not one of them! While it does have the option of paying per hour, per database, per machine size, that’s only one of many ways to use Azure SQL. So I thought it would be worth talking through how pricing works with Azure SQL, and hopefully make it a little simpler to find the right option for you.

Before we get started, I just want to note that when I say Azure SQL, I am referring specifically to Microsoft SQL Server in the cloud. Things like Postgres on Azure are named “Postgres for Azure SQL”, but if you see Azure SQL on it’s lonesome, it means that it’s referring to SQL Server. Easy!

With that out of the way, let’s get started!

Single Database vs Elastic Pool

The first decision you are going to have to make is whether you are going to use a Single Database (Or many Single Databases), or use an Elastic Pool.

Single Database is exactly how it sounds, it’s a price per single database you spin up. It’s important to note this is *not* a single server, but a single database. So if your application uses two databases, for example one for transactional data and another just used for logging, then you will pay for two different AzureSQL databases. The benefit however is that each database has it’s own resources dedicated to it, and therefore they are isolated from one another. A downside is that if your application uses multiple databases (For example a single tenant SAAS application that uses a database per customer), then your costs are going to sky rocket.

Elastic Pools are a collection of SQL databases that share computing power, and pay for a “pool” of resources. Elastic Pools do start with higher pricing than Single Databases (e.g. The minimum spend is much larger than that of a single database), but if you have a data model that requires spinning up multiple databases (And possibly spinning them down), then Elastic Pools are for you. I would note that Elastic Pools also have other factors to consider (e.g. Max DTU sizes), and the shared resources can sometimes be more of a hindrance than a help. For that reason, I only recommend using Elastic Pools when you truly do have a “pool” of databases, like that of a single tenant SAAS application, and to not use Elastic Pools to save a few dollars on hosting costs for your 3 databases in production.

DTU Pricing Model

DTU stands for “Database Transaction Unit”. It’s taking measures of CPU, Memory and IO and combining them into a single metric. That makes it hard to talk about because the first question I usually get fired back when talking about DTU’s is “So how many CPU’s is that? How much memory?”. And the answer is… We don’t know. Or more so, because it’s a blended metric, 1DTU could be comprised of almost all memory and very little CPU, or it could be completely vice versa!

That’s actually one of the benefits of DTU. It’s a single “processing power” metric without having to juggle exact memory or CPU sizes. If you’ve ever had to grab a VM that has a huge amount of memory, but very little CPU, and it’s left you saying “Well.. I just want to increase the CPU, but not the memory, but the next VM class up doubles the memory!”, then that’s why DTUs are in some ways very powerful.

However, clearly a blended metric hides exactly what you are purchasing and for some people that’s a deal breaker. It makes it hard to understand initial provisioning sizes because at first, you will have nothing to compare it to. However, vertical scaling is absolutely no issue with Azure SQL, and so starting low and working your way up is always an option.

vCore Pricing Model

As an alternative to DTU pricing, you can still purchase Azure SQL using the vCore Pricing Model. vCore is your standard Azure SQL on hardware pricing where you know exactly how many CPU Cores and Memory you are being given. It’s great if you know exactly the computing power you need, or prefer the transparency of resourcing over the DTU pricing model.

Under vCore, there is actually two additional options. There is a price per core model, that is great for unpredictable workloads that may need to scale multiple times per day. Under this model, you simply pay per CPU core, per hour. And that’s it!

As an alternative, there is a “standard” set of machines available that are essentially built into your standard “tier” sizes. e.g.  2 Core 10GB, 4 Core 20GB vCore machines. These are great if you know the computing power you need and it won’t need to scale vertically that often.

DTU vs vCore

Unfortunately, after reading all of this you may come to the conclusion that you want to use vCore for it’s transparency, so that you know exactly what you’re getting. And Microsoft knows it, that’s why they’ve put the minimum provisioned vCore Azure SQL prices at around $400 USD per month (depending on region)! There is no lightweight entry into using the vCore pricing model, it’s almost an all or nothing approach.

On the DTU side of things, pricing can start for as little as $15 USD per month (depending on region), and the price step ups are much more granular, making it a much more viable solution for small start-ups and small businesses that just need a single database in the cloud.

Other options include using a DTU pricing model for Dev/Test workloads, and using a vCore model for Production. Again, this works great but only if you are happy with the minimum spend per month for (possibly) far more computing power than you need.

In the end, DTU vs vCore is less about pricing models and how resources are allocated, and more about the minimum level of pricing. In the majority of cases, DTU pricing is the way to go simply so you can start smaller, and ramp up over time.