enterprise library 3.0: overview. context reusable components are important address common...
TRANSCRIPT
Context
Reusable components are important• Address common development challenges consistently
across applications
Application Blocks are a form factor for reusable components• Reusable, extensible and modifiable source code
Enterprise Library is a set of general purpose application blocks• Not specific to any one application type or architectural
style
Can be used as-is or as a starting point for your own libraries or frameworks
p&p Enterprise Library
Enterprise Library Ecosystem
Partner blocks
Customer blocks
Community blocks
p&p blocks
Partner X library
Customer Y library
Customer Z library
Application Block Software Factory andSpecifications
Enterprise Library
Enterprise Library is…
A library of application blocks which solve common challenges
A set of helper classes which work in any architectural style
Architectural guidance embodied in code which ships with full source allowing you to modify and extend
Available as a free download
Enterprise Library is not…
A part of the .NET Framework
An application framework that imposes an architectural style
A Microsoft product with support, compatibility and localization
For sale
Caching
Security
Data Access
Logging
ExceptionHandling
Enterprise Library 3.0 – Application Blocks
Plug-inConfig
Helpers & Design
Instrumen-tation
ObjectBuilder
Cryptography
Core
Policy InjectionValidation
Goals of Enterprise Library 3.0
Address top feedback received for existing application blocks
Provide new application blocks to support additional development challenges
Support integration with relevant features of .NET Framework 3.0
Improve the experience around key development activities
Simplify the development of new application blocks and extensions
Retain compatibility with Enterprise Library 2.0
Enterprise Library 3.0 – New Features At a Glance New application blocks
• Validation Application Block
• Policy Injection Application Block
Improvements to existing application blocks• Data Access Application
Block
• Logging Application Block
.NET Framework 3.0 integration• Logging, Exception Handling
and Validation Application Blocks
Configuration improvements• Visual Studio-integrated
configuration tool
• Environmental Overrides
• Manageable Configuration Source
Automation• Application Block
Software Factory
• Strong Naming Guidance Package
Caching
Security
Data Access
Logging
ExceptionHandling
Enterprise Library 3.0 – Application Blocks
Plug-inConfig
Helpers & Design
Instrumen-tation
ObjectBuilder
Cryptography
Core
Policy InjectionValidation
Configuration
All Enterprise Library blocks are configurable• Controls how the blocks work in your app
• Specifies which plug-ins you are using
Blocks can be used with or without configuration files• Factories build up block objects using data from the
configuration files
• Objects can be “newed up” directly with primitive data types
Configuration stored in standard XML .config files by default• Alternative “Configuration Sources” can be used
• Ships with System, File, Manageable and SQL configuration sources
Configuration Design & Tooling
Configuration tools eliminate the need to edit the blocks’ XML configuration files • Quickly add default configuration for a block
• Strongly typed properties and providers
• Validate configuration before you save
• Encrypt configuration files
• Specify settings that are unique to different environments (development, test, production, etc.)
Visual Studio-integrated editor and standalone console are provided
Configuration Design-time subsystem can be used in your own applications and blocks to provide a similar experience for users of your own blocks and extensions
Instrumentation
All Enterprise Library blocks include instrumentation to assist in development, testing and operations• Event Log events
• Performance Counters
• WMI events
All instrumentation is disabled by default, but each type can be individually enabled using the configuration tool
Installing instrumentation requires admin rights, and can be done using installutil.exe
Instrumentation code contained in Common assembly can be reused in your apps
Object Builder
Shared component used in several p&p deliverables
Responsible for building objects inside the application blocks• Invoking the necessary custom factory using data from
configuration
• Configuring instrumentation for the blocks
Can be leveraged from your own apps, but understanding ObjectBuilder is not required to use Enterprise Library
More information and downloads at http://codeplex.com/objectbuilder
Caching
Security
Data Access
Logging
ExceptionHandling
Enterprise Library 3.0 – Application Blocks
Plug-inConfig
Helpers & Design
Instrumen-tation
ObjectBuilder
Cryptography
Core
Policy InjectionValidation
Exception Handling Scenarios
You need consistent exception handling behavior throughout your application
You need to implement best practice guidance for exception handling• Don’t inadvertently disclose security sensitive information
to remote callers
• Add context to exceptions by wrapping or replacing exceptions with more relevant exceptions
You need to make it simple to add exception management boilerplate code
Exception Handling Application Block Provides simple mechanism that allows you to consistently
deal with exceptions throughout your application
Define “Exception Policies” which link an exception to an action• Exceptions of type ApplicationException should be logged
• Exceptions of type SqlClientException should be caught and wrapped with an exception of type DataLayerException and re-thrown
• Exceptions of type SecurityException should caught and replaced with an AccessDeniedException which will be thrown
Actions provided include• Logging
• Wrapping one exception with another
• Replacing one exception with an other
• Map to WCF Fault Contract
Exception Handling - Example
Try
' some code that may throw
Catch Ex As Exception
If ExceptionPolicy.HandleException(ex, “Data Layer Policy”) Then Throw
End Try
Caching
Security
Data Access
Logging
ExceptionHandling
Enterprise Library 3.0 – Application Blocks
Plug-inConfig
Helpers & Design
Instrumen-tation
ObjectBuilder
Cryptography
Core
Policy InjectionValidation
Logging Scenarios
You need to log business and operations data to various destinations, which are externally configurable
You need to provide tracing to support production debugging
You need to provide auditing for increased security
You need to be able to specify which messages go where, and how they are formatted
You need to be able to log messages to a wide variety of destinations
Logging Application Block
Provides a simple model for logging events• Strongly typed, extensible log schema
Built on top of System.Diagnostics
Configuration driven – you decide what messages are logged where at runtime.
Use any .NET TraceListener, including supplied formatter-aware listeners:• EventLog, Database, Flat File, Rolling Flat File, MSMQ, E-
mail, WMI, XML or create your own
Tracer class lets you time key activities and correlate any enclosed events
Logging - Examples
Dim log As LogEntry = New LogEntry
log.Message = “Your message here…”
log.Priority = 1
log.EventId = 100
log.Categories.Add("UI")
log.Categories.Add("Debug")
Logger.Write(log)
// Or if you prefer one line...
Customer cust = GetCustomer(123);
// Log the customer – will call cust.ToString() for the log entry
Logger.Write(cust, category, priority);
Caching
Security
Data Access
Logging
ExceptionHandling
Enterprise Library 3.0 – Application Blocks
Plug-inConfig
Helpers & Design
Instrumen-tation
ObjectBuilder
Cryptography
Core
Policy InjectionValidation
Data Access Scenarios
You need a simple and efficient way of working with commonly used databases
Transparency when developing for multiple types of databases• SQL Server, SQL Server CE, Oracle, OLE-DB, ODBC, …
A way to place an indirection between a logical database instance and a physical database instance
An easy way to adjust and validate the database configuration settings
Data Access Application Block
Provides simplified access to the most often used features of ADO.NET with applied best practices
Improve Consistency• Write code that works against multiple database brands
(caveats apply!)
• Integrate with System.Transactions functionality
Improve ease of use• Easily call a stored procedure with one line of code
• Let the block manage the lifetime of database connections
• Work with database connection strings stored in configuration or specified in code
Data Access - Examples
Public Function GetProductsInCategory(ByVal Category As Integer) As DataSet ' Create the Database object, using the database instance with the ' specified logical name. This is mapped to a connection string in ' the configuration file Dim db As Database = DatabaseFactory.CreateDatabase("Sales")
' Invoke the stored procedure with one line of code! return db.ExecuteDataSet("GetProductsByCategory", Category)
' Note: connection was closed by ExecuteDataSet method call End Functionpublic Dataset GetProductsInCategory(string connectionString, int
category) { // Create the Database object, using the specified connection string SqlDatabase db = new SqlDatabase(connectionString);
// Invoke the stored procedure with one line of code! return db.ExecuteDataSet("GetProductsByCategory", category);
// Note: connection was closed by ExecuteDataSet method call }
Caching
Security
Data Access
Logging
ExceptionHandling
Enterprise Library 3.0 – Application Blocks
Plug-inConfig
Helpers & Design
Instrumen-tation
ObjectBuilder
Cryptography
Core
Policy InjectionValidation
Caching Scenarios
You are creating a smart client application that uses locally cached reference data to create requests and support offline operations
You are building an application that requires cache data to be durable across application restarts
Note: ASP.NET cache (System.Web.Caching) can be used across multiple application types and is generally a better choice for applications that don’t require the cache to be persisted
Caching Application Block
Provides a flexible and extensible caching mechanism that can be used at all layers of an application
Supports backing stores that persist cache data into a database or isolated storage, so the data can survive app restarts
Thread-safe• Ensures that the states of the in-memory cache and the
backing store remain synchronized.
Caching
Security
Data Access
Logging
ExceptionHandling
Enterprise Library 3.0 – Application Blocks
Plug-inConfig
Helpers & Design
Instrumen-tation
ObjectBuilder
Cryptography
Core
Policy InjectionValidation
Cryptography Scenarios
You need to encrypt sensitive data using a symmetric key before storing in the database and decrypt when reading
You need to encrypt information (without using keys) for use on a single machine
You need to create a hash of a password to store in a database and be able to compare that hash with a user supplied hash to see if you have a match without storing the user password
Cryptography Application Block
Improves Security• Provides a simplified approach to implementing common
cryptography scenarios
Improves Ease Of Use• Provides operations on both strings and byte streams
CreateHash, CompareHash, EncryptSymmetric, DecryptSymmetric
Improves Integration• Supports all .NET crypto algorithms out of the box, or
implement your own
• Supports DPAPI for keyless crypto on a single machine
• Algorithms and keys can be managed through the configuration tool
Caching
Security
Data Access
Logging
ExceptionHandling
Enterprise Library 3.0 – Application Blocks
Plug-inConfig
Helpers & Design
Instrumen-tation
ObjectBuilder
Cryptography
Core
Policy InjectionValidation
Security Scenarios
You need to authorize users• Using one or more security systems or mechanisms
You need to cache authentication or authorization data for the duration of a logon session
Note: The original release of the Enterprise Library Security Application Block also supported Authentication, Profile and Roles. This is now supported by the .NET Membership and Profile class, so this functionality has been removed from the block.
ASP.NET
Security Application Block + ASP.NET
Encapsulate common application security tasks
Present a standard, provider model for common security tasks
Minimize the need for custom security-related code
Incorporate best practices for application security
ClientCode
Security Application Block
Membership
Profile
MembershipProvider
ProfileProvider
AuthorizationFactory
SecurityCache
Factory
IAuthorizationProvider
ISecurityCache
Provider
AuthorizationRule
Provider
CachingStore
Provider
AzManAuthorization
Provider
ActiveDirectoryMembership
Provider
SqlMembership
Provider
SqlProfile
Provider
CachingApplication
Block
Caching
Security
Data Access
Logging
ExceptionHandling
Enterprise Library 3.0 – Application Blocks
Plug-inConfig
Helpers & Design
Instrumen-tation
ObjectBuilder
Cryptography
Core
Policy InjectionValidation
Validation Scenarios
You need to check if data is valid before processing it• Input from end users or untrusted systems
• Improve security and system responsiveness
You need your validation logic to be easy to maintain• During development and after deployment
You need to validate the same data in different layers of an application• Using consistent validation logic
You need to integrate validation seamlessly into different layers of your application• User interface and web service interface layers
Validation Application Block
Specify your validation rules once• In configuration, Using attributes, Programmatically
Easily validate data from anywhere in your application• Programmatically
• Integrated into Windows Forms, ASP.NET or WCF
Composable validation logic• Built-in library of common primitive validation rules
• Combine validation rules on type members and using Boolean logic
• Apply multiple validation rule sets to the same types
Validation Example[StringLengthValidator(1, 50, Ruleset="RuleSetA", MessageTemplate="Last Name must be 1-50 characters")]public string LastName{ get { return lastName; } set { lastName = value; }}
[RegexValidator(@"\w+([-+.']\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*", MessageTemplate="Invalid e-mail address", Ruleset="RuleSetA")]public string Email{ get { return email; } set { email = value; }}
Validator<Customer> validator = ValidationFactory.CreateValidator<Customer>("Ruleset");ValidationResults results = validator.Validate(customer);if (!results.IsValid){ foreach (ValidationResult result in results) { Console.WriteLine("Message={0}, Key={1}, "Tag={2}", result.Message, result.Key.ToString(), result.Tag == null ? "null" : "\"" + result.Tag.ToString() + "\""); }}
Specify validation rules in attributes…
…or in configuration
Validate objects and process results
Caching
Security
Data Access
Logging
ExceptionHandling
Enterprise Library 3.0 – Application Blocks
Plug-inConfig
Helpers & Design
Instrumen-tation
ObjectBuilder
Cryptography
Core
Policy InjectionValidation
Policy Injection Scenarios
Separate cross-cutting concerns from business logic• Use interception and injection to apply policies at runtime
• Provide a declarative way of specifying which policies are applied where
• Allow policies to be defined using configuration or attributes
Integrate Enterprise Library Application Blocks into applications without the need to write code• Validation, Logging, Authorization, Exception Handling,
Caching, Performance Counters
Policy Injection Application Block
Policy Injection Application Block provides a factory for creating or wrapping policy-enabled objects
If policies are defined in attributes or configuration, a proxy is returned in lieu of the real object
When calling policy-enabled members, a handler pipeline is executed before and after the real member is called
Each handler can read and manipulate the data going in and out of the call
Policy Injection Examplepublic class BankAccount : MarshalByRefObject{ // Constructors and fields omitted
[ValidationCallHandler] public void Deposit([RangeValidator(typeof(Decimal), "0.0", RangeBoundaryType.Exclusive, "0.0", RangeBoundaryType.Ignore)] decimal depositAmount) { balance += depositAmount; }}
BankAccount account = PolicyInjection.Create<BankAccount>(customerId);account.Deposit(1234.56M);
Write classes that extend MBRO or
implement an interface
Apply Handlers using attributes if desired
Apply Policies using configuration if desired
Create objects using PolicyInjection class
Call your methods the usual way
Application Block Software Factory
Enterprise Library 3.0 includes a new software factory for building your own application blocks and extensions to existing application blocks
Features include:• Code generation in either C# or Visual Basic .NET
• Solution templates for Application Blocks and Provider Libraries
• Recipes to create custom providers for Enterprise Library application blocks
Including Validators, Trace Listeners, Exception Handlers and Authorization Providers
Strongly-typed or property bag-based configuration
• Recipes to create new factories, provider bases and providers for your own blocks
• Recipes to create design-time configuration code from runtime configuration classes
Strong Naming Guidance Package
Strong-naming Enterprise Library is recommended, but complex• 90+ projects, including design-time and tests
• Use of [InternalsVisibleTo] attribute for testing
Strong Naming Guidance Package automates:• Generating strong-name key pairs
• Specifying that projects should be strong-named
• Updating [InternalsVisibleTo] to include public key
Can be run on Enterprise Library or any other solution
Enterprise Library 3.0 also ships with pre-built, strong-named assemblies which you can use if you don’t want to modify the code.
Resources
Download Enterprise Library and related resources from:• http://msdn.microsoft.com/practices
Join the Enterprise Library Community at:• http://codeplex.com/entlib
Read blogs from the Enterprise Library team at:• http://msdn.microsoft.com/practices/Comm/EntLibBlogs/