Introduction to Azure Logic Apps
Azure Logic Apps is a cloud service that allows developers to schedule, automate, and orchestrate tasks business processes, and workflows that articulate intent via a trigger and series of steps, each invoking an App Service API app whilst securely taking care of authentication and best practices like durable execution.
Every logic app workflow starts with a trigger, which fires when a specific event happens, or when new available data meets specific criteria. Each time when the trigger fires, the Logic Apps engine creates a logic app instance that runs the actions in the workflow.
Lets create a logic apps following below steps.
Login to you Azure Account (https://portal.azure.com), In Home Page, Click on Create a resource button.
After clicking, a New Page appears, Search for Logic App in search bar and you will see a Logic app appears in auto search list, select Logic App.
Once you select Logic app, AÂ Logic App template opens. Click on Create button
After that, a Logic App page appears. Provide details about your logic app.
Select your azure subscription plan, select an existing resource group if not you can create new.
After that you need to specify name for logic app, select location, the region where to store your logic app information. Leave the log Analytics as default set to off.
Finally click on Review + Create button.
After clicking, you can see details for logic app. You can validate and confirm the details that you provided, if all details are correct then you can click on Create button.
Once you click on Create button, You will be getting a message once deployment is done successfully as shown below. Now click on Go To resource.
After clicking, it navigates you on Logic Apps Designer page, there you can see an introduction video and commonly used triggers. You can also choose blank templates for creating a logic apps.
Lets create a logic app for scenario where user sends a Https request and get a response.
Click on Blank Logic App tab.
Once you click, a Logic Apps Designer page opens.
Now we will create a web request, search for a request in search bar and you will see a Request tab appears in lists, click on that as shown in below screenshot.
Now, you need to specify the type for request, select ‘When a Http request is received’ under triggers tab as shown in below screenshot.
After clicking, a When a HTTP request is received page opens.
Here you can see a HTTP POST URL, but we will make it GET URL that will be generated automatically once we save this configuration.
Now for GET URL click on add a new parameter dropdown and select Method.
Once you click on Method, another dropdown box appears that suggest you a various request options such as GET, POST, PUT, DELETE so on.., you need to select GET request.
Once you select GET from dropdown, it is configured successfully.
Now we will create a Response. For this we need to create one more step.
Before that you can hide this request step by clicking on header as shown in below.
Click on New Step.
After clicking, you see a new step added named as choose an operation.
Search for response in search bar, and select a Response in search lists.
In response, leave status code as default to 200 that indicates for success, provide body content.
and Save this configuration.
Once you save this configuration, a HTTP GET URL is generated, just click on ‘When a HTTP request is received header‘ to expand it, there you can see the URL.
Copy the URL and paste it on separate browser window and hit enter button for testing.
You can see, for web request you get a response ‘Response to Request’, that means everything that Logic apps working fine.
Add Parameters in Request URL
You can also add a parameters or you can also call it path parameters in request URL. For adding parameters in request URL, you need go back to Logic app designer.
In Request Step, Click on Add new parameter dropdown box, and check Relative Path as shown below.
After that, specify parameter name in Relative Path that you want to add in Request URL.
Format for parameter will be /{ paramerter_name} as shown below. Here we have added parameters ‘RequestBy’.
After that click on Save button.
Once you save the configuration, a parameter name is added into Request URL that you can check the URL, just scroll on URL to right as shown in below screenshot.
Lets make some changes in response to returning the parameter values on user request.
Now in Response Step, Select body content then you can see right side a pop window opens that suggests you a lists of available dynamic contents, and expression. Also you can there a parameter that you added in your request.
Select that parameter – RequestBy, as we want to return the value of that parameter in response.
Once you select parameter, you can see it is combined with text given in body. Lets save this configuration by clicking on save button.
Now copy the URL as shown below.
Now modify URL, by replacing parameter RequestBy with value that you want to be returned with response text.
After providing a value to parameter in URL, Hit the modified URL in browser.
Once you hit URL on browser, it returns a text with parameter value as shown below.
If you do not want to show curly braces in parameter value, you can remove it from URL when provides a value for parameter.
Also Read.
Create Azure Data Factory Account
Azure Data Factory ETL – Load Blob Storage to Azure SQL Table
