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Manage users in Azure Active Directory. Grant access to users using Role based access control (RBAC)

Sql server connection using Azure active directory Access Token

There are few steps you need to follow to successfully connect to sql server database using App authentication access token.

1) Set yourself@domain.com as Admin in Azure Portal
2) Login to SSMS using yourself@domain.com

3) select database that you want to connect and execute below sql command
this will creates a user with Azure Active Directory mapped to the App Service Principal

CREATE USER [yourAppName] FOR EXTERNAL PROVIDER; 

4) In C# app write logic to get access token to open connection to sql server using yourAppName and secrets
Like below code

private string GetConnectionString() { var builder = new SqlConnectionStringBuilder { DataSource = _sqlConfigs.DatabaseServer, InitialCatalog = _sqlConfigs.DatabaseName, ConnectTimeout = _sqlConfigs.ConnectionTimeoutInSeconds, ConnectRetryCount = _sqlConfigs.ConnectionRetryCount //Below both property only in use if you are using System.data.sqlClient version 4.5.1 or lower //,UserID = _sqlConfigs.DbClientId, //Password = _sqlConfigs.DbClientSecret }; return builder.ConnectionString; }

public async Task GetAccessTokenAsync(string clientId, string clientSecret, string authority, string resource, string scope) { var authContext = new AuthenticationContext(authority, TokenCache.DefaultShared); var clientCred = new ClientCredential(clientId, clientSecret); var result = await authContext.AcquireTokenAsync(resource, clientCred); if (result == null) { throw new InvalidOperationException("error"); } return result.AccessToken; }

public async Task GetSqlConnectionAsync(string tenantId, string clientId, string clientSecret, string dbServer, string dbName)
{
    var authority = string.Format("https://login.windows.net/{0}", tenantId);
    var resource = "https://database.windows.net/";
    var scope = "";
    var token = await GetAccessTokenAsync(clientId, clientSecret, authority, resource, scope);

   var connectionString = GetConnectionString();
   var sqlConnection = new SqlConnection(connectionString){ AccessToken = accessToken };
   sqlConnection.Open();
   return sqlConnection;
}


You can now use GetSqlConnectionAsync method and write your logic to play in database.

Happy coding 😊
Please write comment if you like this or want to know more.

Pull data from Azure Data lake Gen 2 and Write data to sql data warehouse using spark and scala

This article will give you the complete working information to pull data from Azure Data lake Gen 2 and write/push that data to azure SQL data warehouse through Azure Spark using Scala language.

Prerequisite:

1. You should have Azure Subscription
2. Azure SQL data warehouse
3. Azure Blob Storage
4. Blob Container
5. Azure Spark 
6. Azure Data Lake Gen 2 with some sample parquet file in blob container
7. Master Key on Database

Step 0:

Create Master Key to Azure SQL Data warehouse

Open SQL server management studio and connect via your 

• Azure SQL data warehouse Server //Fully Qualified name  suffix with ".database.windows.net"
• You should use SQL authentication "username and password"
• Azure SQL data warehouse username //should be suffix with @yourAzureWareHouseServerName
• Azure SQL data warehouse password 

Once you successfully connected to database than select your data warehouse and open new query window and execute below SQL command that will create master key in Database

To execute this query you need control permission on database

CREATE MASTER KEY ENCRYPTION BY PASSWORD = '23987hxJ#KL95234nl0zBe';


Step 1:

Pull Data to Data Frame using Scala

Write Blow code to Spark Notebook.
Note:- First you have to mount your Azure Data Lake Gen 2 Container to Spark Context. In my case it is "/mnt/blobTestContainer/emp"

val pardf = spark.read.parquet("/mnt/blobTestContainer/emp") //load data frame from parquet file

pardf.createOrReplaceTempView("tempEmp") //create temporary view

val dfEmp = spark.sql("select * from tempEmp") //load data frame from sql view

After Executing your Notebook command your data frame "dfEmp" will be ready

Step 2:

Storage Setting to Write Data to Azure SQL warehouse

Write below code to Spark Notebook. Below settings are required to write data 

val blobStorage = "xxxxxx.blob.core.windows.net" //This should be your fully qualified blob storage name

val blobContainer = "test" //Blob container is required to temporary storage of file, after that Data Ware house pulls data from this temp storage

val blobAccessKey = "cH/xxxxxxxxxxxFBEd3878QPZM9EoYPrkSXXXXXXXXXXXX/eg+rh/IfjxxxxxxxxF6A3BA=="

val tempDir = "wasbs://" + blobContainer + "@" + blobStorage + "/tempDirs" //temp dir storage location

val acntInfo = "fs.azure.account.key."+ blobStorage

sc.hadoopConfiguration.set(acntInfo, blobAccessKey)

Step 3:

SQL Data warehouse related settings

Write below code to spark Notebook. make sure username should be fully qualified name meaning it should be suffix with @yourAzureWareHouseServerName

Data warehouse server name should suffix with ".database.windows.net"

val dwDatabase = "dwTestDB" //This is Data ware house database Name

val dwServer = "xxxxx.database.windows.net" //This is Data ware house server name

val dwUser = "dwuser@dwserver" //This is user name to connect to database. You can get this from azure data ware house property

val dwPass = "XXXXX" //This is password to connect to database. You can get username and password while creating azure data warehouse 

val dwJdbcPort = "1433"

val dwJdbcExtraOptions = "encrypt=true;trustServerCertificate=true;hostNameInCertificate=*.database.windows.net;loginTimeout=30"

val sqlDwUrl = "jdbc:sqlserver://" + dwServer + ":" + dwJdbcPort + ";database=" + dwDatabase + ";user=" + dwUser + ";password=" + dwPass + ";$dwJdbcExtraOptions"

val sqlDwUrlSmall = "jdbc:sqlserver://" + dwServer + ":" + dwJdbcPort + ";database=" + dwDatabase + ";user=" + dwUser + ";password=" + dwPass

Step 4:

Code to Write Data to Azure Data warehouse

Write below code to push data to azure data warehouse. In the blow code we are writing data frame "dfEmp" to azure data warehouse. It will create data table "Emp" in database by reading tempDir and it will automatically create polybase connection underneath. 

spark.conf.set("spark.sql.parquet.writeLegacyFormat","true")

dfEmp.write.format("com.databricks.spark.sqldw").option("url", sqlDwUrlSmall).option("dbtable","Emp").option("forward_spark_azure_storage_credentials","True").option("tempdir",tempDir).mode("overwrite").save()

After All these 5 steps you can connect to you azure data warehouse using SSMS "Sql Server Management Studio" and query on Emp table.

Final Code

Follow above all settings and copy below code to spark notebook and execute together

val pardf = spark.read.parquet("/mnt/blobTestContainer/emp") //load data frame from parquet file

pardf.createOrReplaceTempView("tempEmp") //create temporary view

val dfEmp = spark.sql("select * from tempEmp") //load data frame from sql view

val blobStorage = "xxxxxx.blob.core.windows.net" //This should be your blob fully qualified storage name

val blobContainer = "test" //Blob container is required to temporary storage of file, after that Data Ware house pulls data from this temp storage

val blobAccessKey = "cH/xxxxxxxxxxxFBEd3878QPZM9EoYPrkSXXXXXXXXXXXX/eg+rh/IfjxxxxxxxxF6A3BA=="

val tempDir = "wasbs://" + blobContainer + "@" + blobStorage + "/tempDirs" //temp dir storage location

val acntInfo = "fs.azure.account.key."+ blobStorage

sc.hadoopConfiguration.set(acntInfo, blobAccessKey)

val dwDatabase = "dwTestDB" //This is Data ware house database Name

val dwServer = "xxxxx.database.windows.net" //This is Data ware house server name

val dwUser = "dwuser@dwserver" //This is user name to connect to database. You can get this from azure data ware house property

val dwPass = "XXXXX" //This is password to connect to database. You can get username and password while creating azure data warehouse 

val dwJdbcPort = "1433"

val dwJdbcExtraOptions = "encrypt=true;trustServerCertificate=true;hostNameInCertificate=*.database.windows.net;loginTimeout=30"

val sqlDwUrl = "jdbc:sqlserver://" + dwServer + ":" + dwJdbcPort + ";database=" + dwDatabase + ";user=" + dwUser + ";password=" + dwPass + ";$dwJdbcExtraOptions"

val sqlDwUrlSmall = "jdbc:sqlserver://" + dwServer + ":" + dwJdbcPort + ";database=" + dwDatabase + ";user=" + dwUser + ";password=" + dwPass

spark.conf.set("spark.sql.parquet.writeLegacyFormat","true")

dfEmp.write.format("com.databricks.spark.sqldw").option("url", sqlDwUrlSmall).option("dbtable","Emp").option("forward_spark_azure_storage_credentials","True").option("tempdir",tempDir).mode("overwrite").save()

Hope this code will help you. Write comment If you need any help or for any suggestion.

Happy coding. 

Create your own custom ArrayList in c#

As per Microsoft c# team:

Initial capacity of an ArrayList in .NET 1.0 is 16. In 2.0 it was 4, and now - with .NET 3.5 - the initial capacty has been lowered to 0. I don't have an explanation of why, thou. When adding a first element to the list, the capacity will be set to 4. There after, every time when arraylist.Count eq arraylist.Capacity, the capacity will double.

Below code is just for reference  that how we can create custom ArrayList. In the below example I have just increased 1 size at a time. But the default size is 10 

class CArray
    {
        private int[] arr;
        private int upper;
        private int numElements;
        public CArray(int size)
        {
            arr = new int[size];
            upper = size - 1;
            numElements = 0;
        }
        public void Insert(int item)
        {
            if(numElements == arr.Length) //reallocate size
            {
                IncreaseArraySize();
                upper = arr.Length - 1;
            }

            arr[numElements] = item;
            numElements++;
        }
        public void DisplayElements()
        {
            for (int i = 0; i <= upper; i++)
            {
                Console.Write(arr[i] + " ");
                Console.WriteLine();
            }
        }
        public void Clear()
        {
            for (int i = 0; i <= upper; i++)
            {
                arr[i] = 0;
                numElements = 0;
            }
        }

        public void IncreaseArraySize()
        {
            Array.Resize(ref arr, arr.Length + 1);
        }
}

class Program
    {
        static void Main(string[] args)
        {
            CArray nums = new CArray(10);

            Random rnd = new Random(100);

            for (int i = 0; i < 10; i++)
            {
                nums.Insert((int)(rnd.NextDouble() * 100));
            }

            nums.Insert(203); //Dynamic size allocation here
            nums.Insert(2);

            nums.DisplayElements();
         
        }
    }

Note: This is not the exact implementation of ArrayList in C# , this is just a reference 

How to replace kendo grid odata parameter using parametermap

parameterMap: function (data, operations) {
                    var paramMap = kendo.data.transports.odata.parameterMap(data);
                    if (paramMap.$inlinecount) {
                        if (paramMap.$inlinecount == "allpages") {
                            paramMap.$count = true;
                        }
                        delete paramMap.$inlinecount;
                    }
                    if (paramMap.$take) {
                        paramMap.$top = paramMap.$take;
                        delete paramMap.$take;
                    }
                    if (paramMap.$filter) {
                        paramMap.$filter = paramMap.$filter.replace(/substringof\((.+),(.*?)\)/, "contains($2,$1)");
                    }
                    return paramMap;
                }

OData using ODataQueryOptions $count $select $expand $filter without using [EnableQuery] attribute

If you are using OData controller without using [EnableQuery] attribute, Below example help you to get all your odata query

Odata Query

/odata/GetTestData?$format=json&$filter=(Name+eq+'santosh'+AND+Age+eq+30)&$select=Name,Address&$top=50&$count=true

Step 1:

declare temp variable and load data from your repository like below:

IQueryable tempQuery = repo.GetTestData();
IQueryable result = tempQuery;

Step 2:

Add below lines of code to apply your query.
for $count- get count() from temp result variable so that you will get all data count

if (opts.Filter != null){
tempQuery = opts.Filter.ApplyTo(tempQuery, new ODataQuerySettings()) as Queryable;
}
if (opts.Top != null){
tempQuery = opts.Top.ApplyTo(tempQuery, new ODataQuerySettings()) as IQueryable;
}
if (opts.Skip != null){
tempQuery = opts.Skip.ApplyTo(tempQuery, new ODataQuerySettings()) as IQueryable;
}
if (opts.OrderBy != null){
tempQuery = opts.OrderBy.ApplyTo(tempQuery, new ODataQuerySettings()) as Queryable;
}
if (opts.SelectExpand != null){
Request.ODataProperties().SelectExpandClause = opts.SelectExpand.SelectExpandClause;
}
 if (opts.Count != null)
{
Request.ODataProperties().TotalCount = result.Count();
}

Step 3:
Final full Odata Controller code

//Web API Odata Controller

 [HttpGet]
 [ODataRoute("GetTestData")]
public IQueryable GetTestData(ODataQueryOptions opts)
        {
            
            var repo = unitOfWork.TestRepository;

            IQueryable tempQuery = repo.GetTestData();
            IQueryable result = tempQuery;

            if (opts.Filter != null){
                tempQuery = opts.Filter.ApplyTo(tempQuery, new ODataQuerySettings()) as IQueryable;
}
            if (opts.Top != null){
                tempQuery = opts.Top.ApplyTo(tempQuery, new ODataQuerySettings()) as IQueryable;
}
            if (opts.Skip != null){
                tempQuery = opts.Skip.ApplyTo(tempQuery, new ODataQuerySettings()) as IQueryable;
}
            if (opts.OrderBy != null){
                tempQuery = opts.OrderBy.ApplyTo(tempQuery, new ODataQuerySettings()) as IQueryable;
}
            if (opts.SelectExpand != null){
                Request.ODataProperties().SelectExpandClause = opts.SelectExpand.SelectExpandClause;
}
            if (opts.Count != null)
            {
                Request.ODataProperties().TotalCount = result.Count();
            }

            result = tempQuery.ToList().AsQueryable();

            return result;
        }

Happy coding👍