Use Biml to Build SSIS Tasks to Replicate Google Cloud Storage Data to SQL Server

Jerod Johnson
Director, Technology Evangelism

Use Biml to dynamically build SSIS tasks using CData SSIS Components to replicate Google Cloud Storage data to SQL Server.

Using SQL Server as a backup for critical business data provides an essential safety net against loss and enables business users to more easily connect that data with features like reporting, analytics, and more. Biml is an XML dialect that can be used to create Microsoft SQL Server BI objects, like SSIS packages. Pairing CData SSIS Components with Biml empowers you to easily build SSIS packages with access to Google Cloud Storage data. Key benefits include:

Built-in metadata discovery — CData SSIS components expose metadata just like working with SQL Server, even dynamically generating schema for schema-less data sources
Dynamic SSIS task generation — Use code nuggets in Biml to build SSIS tasks by iterating over discovered metadata
Read from Google Cloud Storage — Native source components make Google Cloud Storage look just like a database

This article demonstrates how to use Biml with the CData SSIS Components for Google Cloud Storage to dynamically build SSIS tasks (one for each Google Cloud Storage entity) to replicate Google Cloud Storage data to a Microsoft SQL Server database. We step through the Biml file one section at a time but have included the complete Biml file at the end of the article.

In order to use Biml in an SSIS Project in Visual Studio, install BimlExpress. Once you install BimlExpress, open Visual Studio, create a new Integration Services project, and add a new Biml file.

👁 Add a new Biml file to the SSIS project

Building the Biml File

With Biml, you can write scripting to dynamically generate SSIS projects, packages, and tasks. To see the Biml file for an existing project (and gain insights on using Biml with CData SSIS Tasks), simply create your tasks and then right-click the project and select Convert SSIS Packages to Biml.

C# Code

Use directives <#@ .. #> to import necessary namespaces and the assembly for the CData SSIS Components for Google Cloud Storage.

<#@ template language="C#" hostspecific="true"#>
<#@ import namespace="System.Data"#>
<#@ import namespace="System.IO"#>
<#@ import namespace="System.Collections"#>
<#@ import namespace="System.Data.CData.GoogleCloudStorage"#>
<#@ assembly name="C:\Program Files\CData[product_name] 2018\lib\CData.SSIS2017.GoogleCloudStorage.dll"#>

In a new control nugget <# ... #>, create variables for values that will be used throughout the Biml script, including a connection string for Google Cloud Storage and structures to store the Google Cloud Storage metadata.

Authenticate with a User Account

You can connect without setting any connection properties for your user credentials. After setting InitiateOAuth to GETANDREFRESH, you are ready to connect.

When you connect, the Google Cloud Storage OAuth endpoint opens in your default browser. Log in and grant permissions, then the OAuth process completes

Authenticate with a Service Account

Service accounts have silent authentication, without user authentication in the browser. You can also use a service account to delegate enterprise-wide access scopes.
You need to create an OAuth application in this flow. See the Help documentation for more information. After setting the following connection properties, you are ready to connect:
- InitiateOAuth: Set this to GETANDREFRESH.
- OAuthJWTCertType: Set this to "PFXFILE".
- OAuthJWTCert: Set this to the path to the .p12 file you generated.
- OAuthJWTCertPassword: Set this to the password of the .p12 file.
- OAuthJWTCertSubject: Set this to "*" to pick the first certificate in the certificate store.
- OAuthJWTIssuer: In the service accounts section, click Manage Service Accounts and set this field to the email address displayed in the service account Id field.
- OAuthJWTSubject: Set this to your enterprise Id if your subject type is set to "enterprise" or your app user Id if your subject type is set to "user".
- ProjectId: Set this to the Id of the project you want to connect to.
The OAuth flow for a service account then completes.
```
var googlecloudstorageConnectionString = "ProjectId='project1';InitiateOAuth=GETANDREFRESH;";
var replicationServer = "SERVER";
var replicationCatalog = "CATALOG";
var replicationUserID = "sqluser";
var replicationPassword = "sqlpassword";

List<string> allEntityNames = new List<string>();
Hashtable entitySchema = new Hashtable();
```

In the same control nugget used to defined variables, use ADO.NET code to programmatically query the Google Cloud Storage entities (tables) and fields (columns).

using (GoogleCloudStorageConnection connection = new GoogleCloudStorageConnection(googlecloudstorageConnectionString)) {
 connection.Open();
 var entities = connection.GetSchema("Tables").Rows;
 foreach (DataRow entity in entities)
 {
 allEntityNames.Add(entity["TABLE_NAME"].ToString());
 }
 foreach (string entity in allEntityNames){
 var columns = connection.GetSchema("Columns", new string [] {entity}).Rows;
 entitySchema.Add(entity,columns);
 }
}

Class Nugget

In our Biml script to create the replication tasks, there are several places where repeated XML elements are created dynamically (mostly for columns in SSIS tasks). Instead of repeating the code, add a class nugget <#+ ... #> and create a helper class with methods to consolidate repeated code (full code at the end of the article).

Add public static variables to determine which type of XML element to create.

public static int OUTPUT_WITH_ERROR = 0;
public static int EXTERNAL = 1;
public static int OUTPUT = 2;
public static int DATAOVERRIDE_COLUMN = 4;

Add a public method to build a SQL statement for use in the ExecuteSQL task used to drop existing tables and create a new table for the replicated data.

// Dynamically builds a DROP TABLE and CREATE statement
// for each entity (table) in Google Cloud Storage using the table name and metadata.
public static string GetDeleteAndCreateStatement(string tableName, DataRowCollection columns) {
 ...
}

Add a public method to build the collection of column-based XML elements.

 
// Dynamically build various column-based XML elements
// for each entity (table) in Google Cloud Storage based on the column 
// metadata and the parent element
public static string GetColumnDefs(DataRowCollection columns, int columnType){
 ...
}

Biml Script

Now that you have the table metadata and a Helper class to reduce repeated code, write the Biml script to dynamically create your replication packages.

Start by adding a CustomSsisConnection element for the CData SSIS Tasks. Note that the ObjectData attribute must be XML encoded. A typical connecting string looks similar to the following (note the use of the googlecloudstorageConnectionString variable for the ConnectionString property:

<GoogleCloudStorageConnectionManager>
 <Property Name="ConnectionString"><#=googlecloudstorageConnectionString#></Property>
</GoogleCloudStorageConnectionManager>

After configuring the connection to the CData SSIS Task, configure a connection to the replication database. The completed Connections element looks like the following (note the use of text nuggets <#= ... #> to add variables for connection string values):

<Connections>
 <CustomSsisConnection Name="CData GoogleCloudStorage Connection Manager" CreationName = "CDATA_GOOGLECLOUDSTORAGE" ObjectData = "&lt;GoogleCloudStorageConnectionManager&gt; &lt;Property Name=&quot;ConnectionString&quot;&gt; <#=googlecloudstorageConnectionString#>&lt;/Property&gt; &lt;/GoogleCloudStorageConnectionManager&gt;" />
 <Connection Name="Destination" ConnectionString="Data Source=<#=replicationServer#>;User ID=<#=replicationUserID#>;Password=<#=replicationPassword#>;Initial Catalog=<#=replicationCatalog#>;Provider=SQLNCLI11.1;"/>
</Connections>

With the Connections element configured, you are ready to build our replication package. In the package, the Biml script create an ExecuteSQL task and a Dataflow task for each table to be replicated.

To build each set of tasks, use a while loop in a control nugget to iterate through the entity (table) names:

int entityCounter = 0; while(entityCounter < allEntityNames.Count){
var tableName = allEntityNames[entityCounter].ToString();
DataRowCollection columns = ((DataRowCollection)entitySchema[tableName]);

ExecuteSQL Task
In the ExecuteSQL task, execute a SQL query to drop any existing tables that have the same name as our Google Cloud Storage entity (table) and create a new table based on the metadata discovered using the CData SSIS Component.

To create the query dynamically, use the Helper.GetDeleteAndCreateStatement() helper function.

Dataflow Task

Within the Dataflow use a CustomComponent as the source component and an OleDbDestination as the destination.

CustomComponent Element

The CustomComponent element uses the CData SSIS Source component to retrieve Google Cloud Storage data. Start by configuring the component to use with the CData component.

<CustomComponent Name="CData Google Cloud Storage Source" ComponentTypeName="CData.SSIS.GoogleCloudStorage.GoogleCloudStorageSource" Version="18" ContactInfo="[email protected]" UsesDispositions="true">
...
</CustomComponent>

DataflowOverrides and OutputPaths Elements

The next step after configuring the connection is to add Columns elements to the OutputPath child element of the DataflowOverrides element. To do so, call the Helper.GetColumnDefs() helper function.

Use the same Helper class to add columns to the OutputColumns and ExternalColumns child elements of the various OutputPaths elements.

The definitions created provide information about the input, output, and error information for the SSIS component.

<DataflowOverrides>
 <OutputPath OutputPathName="CData GoogleCloudStorage Source Output">
 <Columns>
<#=HelperClass.GetColumnDefs(columns,HelperClass.DATAOVERRIDE_COLUMN) #>
 </Columns>
 </OutputPath>
</DataflowOverrides>
...
<OutputPaths>
 <OutputPath Name="CData GoogleCloudStorage Source Output">
 <OutputColumns>
<#=HelperClass.GetColumnDefs(columns,HelperClass.OUTPUT_WITH_ERROR) #>
 </OutputColumns>
 <ExternalColumns>
<#=HelperClass.GetColumnDefs(columns,HelperClass.EXTERNAL) #>
 </ExternalColumns>
 </OutputPath>
 <OutputPath Name="CData GoogleCloudStorage Source Error Output" IsErrorOutput="true">
 <OutputColumns>
<#=HelperClass.GetColumnDefs(columns,HelperClass.OUTPUT) # 
 </OutputColumns>
 </OutputPath>
</OutputPaths>

CustomProperties Element

The CData SSIS tasks are surfaced in SSIS as custom components with a series of required CustomProperties:

<CustomProperties>
 <CustomProperty Name="SQLStatement" DataType="Null" UITypeEditor="Microsoft.DataTransformationServices.Controls.ModalMultilineStringEditor, Microsoft.DataTransformationServices.Controls, Version= 10.0.0.0, Culture=neutral, PublicKeyToken=89845dcd8080cc91" SupportsExpression="true"></CustomProperty>
 <CustomProperty Name="AccessMode" DataType="Int32" TypeConverter="CData.SSIS.GoogleCloudStorage.AccessModeToStringConverter">0</CustomProperty>
 <CustomProperty Name="TableOrView" DataType="String" UITypeEditor="Microsoft.DataTransformationServices.Controls.ModalMultilineStringEditor, Microsoft.DataTransformationServices.Controls, Version= 10.0.0.0, Culture=neutral, PublicKeyToken=89845dcd8080cc91" SupportsExpression="true">[<#=tableName#>]</CustomProperty>
 <CustomProperty Name="ExecStoredProcedure" DataType="Boolean">false</CustomProperty>
</CustomProperties>

Connections Element

The last element to add to the CustomComponent element is a Connections element, attaching the previously defined connection to the task:

<Connections>
 <Connection Name="GoogleCloudStorage 2018 Connection" ConnectionName="CData GoogleCloudStorage Connection Manager" />
</Connections>

OleDbDestination Element

The final piece of the Dataflow task is the OleDbDestination element. Attach the previously defined OleDbConnection to the element, set the InputPath and ExternalTableOutput:

<OleDbDestination Name="OLE DB Destination" ConnectionName="Destination" CheckConstraints="false">
 <InputPath OutputPathName="CData GoogleCloudStorage Source.CData GoogleCloudStorage Source Output" />
 <ExternalTableOutput Table="[<#=tableName#>]" />
</OleDbDestination>

Use a control nugget to increment the counter used to iterate over the collection of entity (table) names. Do this within the Tasks element, after the end of the Dataflow element:
```
...
 </Dataflow> 
<# entityCounter++;}#>
 </Tasks>
 </Package>
 </Packages>
</Biml>
```

Build the SSIS Project

Once the Biml file is written, right-click on the Biml file in Server Explorer and select Generate SSIS Packages. At this point, Visual Studio and BimlExpress will translate the Biml file into SSIS package(s), ready to be run.

👁 Generate SSIS Package(s) from Biml

Run the package to begin replicating your Google Cloud Storage data to a SQL Server database (or any other destination you choose).

Free Trial & More Information

With the CData SSIS Components for Google Cloud Storage, you get SQL access to your Google Cloud Storage data directly from SSIS packages. And with Biml, you can automatically generate those packages. For more information about the CData SSIS Components for Google Cloud Storage, refer to the product page. You can always get started with a free, 30-day trial. As always, our world-class CData Support Team is available if you have any questions.

Complete Biml File

<#@ template language="C#" hostspecific="true"#>
<#@ import namespace="System.Data"#>
<#@ import namespace="System.IO"#>
<#@ import namespace="System.Collections"#>
<#@ import namespace="System.Data.CData.GoogleCloudStorage"#>
<#@ assembly name="C:\Program Files\CData\CData SSIS Components for GoogleCloudStorage 2018\lib\CData.SSIS2017.GoogleCloudStorage.dll"#>
<#
var googlecloudstorageConnectionString = "ProjectId='project1';InitiateOAuth=GETANDREFRESH;";
var replicationServer = "JDG";
var replicationCatalog = "BIML";
var replicationUserID = "sqltest";
var replicationPassword = "sqltest";

List<string> allEntityNames = new List<string>();
Hashtable entitySchema = new Hashtable();
using (GoogleCloudStorageConnection connection = new GoogleCloudStorageConnection(googlecloudstorageConnectionString)) {
 connection.Open();
 var entities = connection.GetSchema("Tables").Rows;
 foreach (DataRow entity in entities)
 {
 allEntityNames.Add(entity["TABLE_NAME"].ToString());
 }
 foreach (string entity in allEntityNames){
 var columns = connection.GetSchema("Columns", new string [] {entity}).Rows;
 entitySchema.Add(entity,columns);
 }
}#>
<Biml xmlns="http://schemas.varigence.com/biml.xsd">
 <Connections>
 <CustomSsisConnection Name="CData GoogleCloudStorage Connection Manager" CreationName="CDATA_GOOGLECLOUDSTORAGE" ObjectData="&lt;GoogleCloudStorageConnectionManager&gt;&lt;Property Name=&quot;ConnectionString"&gt;<#=googlecloudstorageConnectionString#>&lt;/Property&gt;&lt;/GoogleCloudStorageConnectionManager&gt;"/>
 <Connection Name="Destination" ConnectionString="Data Source=<#=replicationServer#>;User ID=<#=replicationUserID#>;Password=<#=replicationPassword#>;Initial Catalog=<#=replicationCatalog#>;Provider=SQLNCLI11.1;"/>
 </Connections>
 <Packages>
 <Package Name="Replicate GoogleCloudStorage Package" Language="None" ConstraintMode="LinearOnCompletion" ProtectionLevel="EncryptSensitiveWithUserKey">
 <Tasks>
<# int entityCounter = 0; while(entityCounter < allEntityNames.Count){
 var tableName = allEntityNames[entityCounter].ToString();
 if (tableName.Equals("IdpEventLog")) break;
 DataRowCollection columns = ((DataRowCollection)entitySchema[tableName]);#>
 <ExecuteSQL Name="Create <#=tableName#> Replication Table" ConnectionName="Destination">
 <DirectInput>
<#=HelperClass.GetDeleteAndCreateStatement(tableName,columns)#>
 </DirectInput>
 </ExecuteSQL>
 <Dataflow Name="Replicate <#=tableName#>">
 <Transformations>
 <CustomComponent Name="CData GoogleCloudStorage Source" ComponentTypeName="CData.SSIS.GoogleCloudStorage.GoogleCloudStorageSource" Version="18" ContactInfo="[email protected]" UsesDispositions="true">
 <DataflowOverrides>
 <OutputPath OutputPathName="CData GoogleCloudStorage Source Output">
 <Columns>
<#=HelperClass.GetColumnDefs(columns,HelperClass.DATAOVERRIDE_COLUMN) #>
 </Columns>
 </OutputPath>
 </DataflowOverrides>
 <CustomProperties>
 <CustomProperty Name="SQLStatement" DataType="Null" UITypeEditor="Microsoft.DataTransformationServices.Controls.ModalMultilineStringEditor, Microsoft.DataTransformationServices.Controls, Version= 10.0.0.0, Culture=neutral, PublicKeyToken=89845dcd8080cc91" SupportsExpression="true"></CustomProperty>
 <CustomProperty Name="AccessMode" DataType="Int32" TypeConverter="CData.SSIS.GoogleCloudStorage.AccessModeToStringConverter">0</CustomProperty>
 <CustomProperty Name="TableOrView" DataType="String" UITypeEditor="Microsoft.DataTransformationServices.Controls.ModalMultilineStringEditor, Microsoft.DataTransformationServices.Controls, Version= 10.0.0.0, Culture=neutral, PublicKeyToken=89845dcd8080cc91" SupportsExpression="true">[<#=tableName#>]</CustomProperty>
 <CustomProperty Name="ExecStoredProcedure" DataType="Boolean">false</CustomProperty>
 </CustomProperties>
 <OutputPaths>
 <OutputPath Name="CData GoogleCloudStorage Source Output">
 <OutputColumns>
<#=HelperClass.GetColumnDefs(columns,HelperClass.OUTPUT_WITH_ERROR) #>
 </OutputColumns>
 <ExternalColumns>
<#=HelperClass.GetColumnDefs(columns,HelperClass.EXTERNAL) #>
 </ExternalColumns>
 </OutputPath>
 <OutputPath Name="CData GoogleCloudStorage Source Error Output" IsErrorOutput="true">
 <OutputColumns>
<#=HelperClass.GetColumnDefs(columns,HelperClass.OUTPUT) #> 
 </OutputColumns>
 </OutputPath>
 </OutputPaths>
 <Connections>
 <Connection Name="GoogleCloudStorage 2018 Connection" ConnectionName="CData GoogleCloudStorage Connection Manager" />
 </Connections>
 </CustomComponent>
 <OleDbDestination Name="OLE DB Destination" ConnectionName="Destination" CheckConstraints="false">
 <InputPath OutputPathName="CData GoogleCloudStorage Source.CData GoogleCloudStorage Source Output" />
 <ExternalTableOutput Table="[<#=tableName#>]" />
 </OleDbDestination>
 </Transformations>
 </Dataflow> 
<# entityCounter++;}#>
 </Tasks>
 </Package>
 </Packages>
</Biml>

<#+
public static class HelperClass {
 
 public static int OUTPUT_WITH_ERROR = 0;
 public static int EXTERNAL = 1;
 public static int OUTPUT = 2;
 public static int DATAOVERRIDE_COLUMN = 4;
 
 public static string GetDeleteAndCreateStatement(string tableName, DataRowCollection columns) {
 var dropAndCreateStatement = 
 "IF EXISTS (SELECT * FROM sys.objects WHERE object_id = OBJECT_ID(N'[{0}]') AND type IN (N'U'))\r\n" + 
 "DROP TABLE [{0}];\r\n" + 
 "CREATE TABLE [{0}]\r\n" + 
 "(\r\n" + 
 "{1}\r\n" + 
 ")\r\n" + 
 "ON \"default\";";
 string columnDefs = "";
 foreach (DataRow column in columns){
 string columnDef = " [{0}] {1}";
 string dataType = column["DATA_TYPE"].ToString();
 if (dataType.ToLower().StartsWith("bool")) {
 dataType = "bit";
 } else if (dataType.ToLower().Equals("real")) {
 dataType = "float";
 } else if (dataType.ToLower().Contains("varchar")) {
 var columnLength = column["CHARACTER_MAXIMUM_LENGTH"];
 dataType = "nvarchar(" + ((int)columnLength > 4000 ? "MAX" : columnLength) + ")"; 
 } 
 columnDefs += String.Format(columnDef,column["COLUMN_NAME"],dataType) + ",\r\n";
 
 }
 columnDefs = columnDefs.Remove(columnDefs.LastIndexOf(",\r\n"),",\r\n".Length);
 return String.Format(dropAndCreateStatement,tableName,columnDefs);
 }
 
 public static string GetColumnDefs(DataRowCollection columns, int columnType){
 var columnDefTemplate = "";
 var columnElements = "";
 
 if (columnType == DATAOVERRIDE_COLUMN) {
 columnDefTemplate = " <Column ErrorRowDisposition=\"FailComponent\" TruncationRowDisposition=\"FailComponent\" ColumnName=\"{0}\" />\r\n";
 foreach(DataRow column in columns) {
 var columnName = column["COLUMN_NAME"];
 columnElements += String.Format(columnDefTemplate,columnName);
 }
 return columnElements;
 } 
 if (columnType == OUTPUT_WITH_ERROR)
 columnDefTemplate = " <OutputColumn Name=\"{0}\" {1} ExternalMetadataColumnName=\"{0}\" ErrorRowDisposition=\"FailComponent\" TruncationRowDisposition=\"FailComponent\" />\r\n";
 else if (columnType == EXTERNAL)
 columnDefTemplate = " <ExternalColumn Name=\"{0}\" {1} />\r\n";
 else if (columnType == OUTPUT)
 columnDefTemplate = " <OutputColumn Name=\"{0}\" {1} />\r\n";
 
 foreach(DataRow column in columns){ 
 var columnName = column["COLUMN_NAME"];
 var dataTypeRaw = column["DATA_TYPE"].ToString().ToLower();
 var typeAndRelatedInfo = "";
 if (dataTypeRaw.Equals("bool")) {
 typeAndRelatedInfo = "DataType=\"Boolean\"";
 } else if (dataTypeRaw.Equals("date")) {
 typeAndRelatedInfo = "DataType=\"Date\" SsisDataTypeOverride=\"DT_DBDATE\"";
 } else if (dataTypeRaw.Equals("datetime")) {
 typeAndRelatedInfo = "DataType=\"DateTime\"";
 } else if (dataTypeRaw.Equals("real")) {
 typeAndRelatedInfo = ((int)column["NumericPrecision"] > 0 ? "Precision=\"18\" " : " ") + ((int)column["NumericScale"] > 0 ? "Scale=\"15\" " : " ") + "DataType=\"Decimal\"";
 } else if (dataTypeRaw.Equals("varchar")) {
 var columnLength = column["CHARACTER_MAXIMUM_LENGTH"];
 if ((int)columnLength > 4000) {
 typeAndRelatedInfo = "DataType=\"String\"";
 } else {
 typeAndRelatedInfo = "Length=\"" + columnLength + "\" DataType=\"String\" CodePage=\"1252\"";
 }
 }
 columnElements += String.Format(columnDefTemplate,columnName,typeAndRelatedInfo);
 }
 return columnElements;
 }
}
#>

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Google Cloud Storage SSIS Components

Powerful SSIS Source & Destination Components that allows you to easily connect SQL Server with Google Cloud Storage through SSIS Workflows.

Use the Google Cloud Storage Data Flow Components to synchronize with Google Cloud Storage Buckets, Objects, and more. Perfect for data synchronization, local back-ups, workflow automation, and more!

URL: https://www.cdata.com/kb/tech/googlecloudstorage-ssis-biml-replication.rst