How to Make Use of Azure Cognitive Services

Azure Cognitive Services is a service that is available from your Azure portal which allows you to set-up accounts that enable the use of Microsoft’s pre-built algorithms and models for common advanced analytical functions such as Text Analytics, Recommendation Engines, speech and vision recognition as well as many more service-oriented APIs. These models have been trained and are ready for you to use and consume in your solutions, such as Power BI business intelligence solutions.

There is a very common use case emerging that I’m finding in the Cloud Analytics space that relates specifically to a portion of the Text Analytics function where there are a number of solutions that can take advantage of the Sentiment Analysis capabilities that Azure Cognitive Services provides. By sending in a text string to the API service, you can leverage the existing Microsoft sentiment engine to determine if the message that you sent in is positive, negative or neutral based upon a score.

The best way to demonstrate this is with Power BI. I am going to briefly touch on 2 of the most common social media sources to pull real-time data from and core the messages for sentiment analysis: Twitter & Facebook.

First, the easiest with Power BI (PBI) is Facebook. There is an out-of-the-box connector for Facebook included with PBI, so you can use Get Data to bring data directly into a Power BI model from Facebook very easily:


Now, to hook into the Microsoft Sentiment Analysis, follow the method described very well on this PBI community page and from the associated PASS Virtual Chapter presentation on this very topic by Gil from DataChant: His full working sample is awesome and you can play around with it here:

To download and use a similar sample in the PBI Desktop, just download the PBIX from my Github. I recommend going into the detailed PBI Community link from Gil above, it rocks and gives you the background you need to customize this for yourself with step-by-step instructions on how this was made.

For the demo above that I uploaded to Github, I included Gil’s Trump & Clinton Facebook election sentiment analysis data on Tab 2 of the report view on PBI. Tab 1 has Microsoft BI Facebook sentiment data where I used the Microsoft BI Facebook page as the data source. Each of those datasets is run through the Cognitive Services API for Sentiment Analysis, part of the Text Analytics suite.

To make it work for you, follow Gil’s instructions on getting an API key from Cognitive Services and plug in your API Key in the GetSentimentResults function in the Power Query / Edit query tool. You can use the free limited service for Sentiment Analysis or go to the Azure Portal and create a full-use Cognitive Services account. The code for calling out to the API and saving the sentiment score in the PBI model is in a Power Query function call in the PBIX and looks like this:

(Source as table) as any =>
JsonRecords = Text.FromBinary(Json.FromValue(Source)),
JsonRequest = “{“”documents””: ” & JsonRecords & “}”,

JsonContent = Text.ToBinary(JsonRequest, TextEncoding.Ascii),
Response =
Headers = [#”Ocp-Apim-Subscription-Key”= “your api key here”,
#”Content-Type”=”application/json”, Accept=”application/json”],
JsonResponse = Json.Document(Response,1252)

As you can tell from my sample Sentiment Facebook dashboard below, I did not put as much time into the report as Gil did. So take the PBIX and add your own visuals to make it better!


Now onto the 2nd example, using Twitter data. There is no out-of-the-box connector directly into PBI for live Twitter feeds, so I used the Solution Template for Twitter (Marketing use case) from the Power BI Solution Template site:

That site provides you with a “wizard” that walks through the set-up of an Azure SQL Database, your Cognitive Services API as I mentioned above (free or the Azure account) and the Twitter handles/keywords that you want to use as a filter. This creates a much more robust solution to grab the Twitter data in that the solution template with spin-up Logic Apps, App Service and API connectors to Twitter and Sentiment Analysis on the backend instead of directly from Power BI as the first example with Facebook above.

So, essentially Power BI will just connect to your Azure SQL DB that you’ve chosen from the template and that SQL DB will get populated from the Azure App that is built automatically for you. This separates the data from the business logic and from the presentation layer in PBI. The code to call Twitter and Cognitive Services are all in the “middle tier” on the App Service in Azure, which you can open directly from your Azure Portal. Modify the API calls, strings and sentiment bins in that code:

//Sentiment analysis – Cognitive APIs
string sentiment = await MakeSentimentRequest(tweet);
sentiment = (double.Parse(sentiment) * 2 – 1).ToString(CultureInfo.InvariantCulture);
string sentimentBin = (Math.Floor(double.Parse(sentiment) * 10) / 10).ToString(CultureInfo.InvariantCulture);
string sentimentPosNeg = String.Empty;
if (double.Parse(sentimentBin) > 0)
sentimentPosNeg = “Positive”;
else if (double.Parse(sentimentBin) < 0)
sentimentPosNeg = “Negative”;
sentimentPosNeg = “Neutral”;

The out-of-the-box reports from these Power BI templates are quite good with a social graph visualization and a number of report tabs for different pivots of the Twitter data and sentiment scores.