问题
I am building an MVC 4 application, using EF 5. I need to do an audit trail, ie log any changes that end users make.
I have asked this question a few times, but haven't really gotten a satisfying answer before. So I am adding a lot more details in hoping to get somewhere..
currently I have multiple repositories
ie
public class AuditZoneRepository : IAuditZoneRepository
{
private AISDbContext context = new AISDbContext();
public int Save(AuditZone model, ModelStateDictionary modelState)
{
if (model.Id == 0)
{
context.AuditZones.Add(model);
}
else
{
var recordToUpdate = context.AuditZones.FirstOrDefault(x => x.Id == model.Id);
if (recordToUpdate != null)
{
recordToUpdate.Description = model.Description;
recordToUpdate.Valid = model.Valid;
recordToUpdate.ModifiedDate = DateTime.Now;
}
}
try
{
context.SaveChanges();
return 1;
}
catch (Exception ex)
{
modelState.AddModelError("", "Database error has occured. Please try again later");
return -1;
}
}
}
public class PostcodesRepository : IPostcodesRepository
{
private AISDbContext context = new AISDbContext();
public int Save(Postcodes model, ModelStateDictionary modelState)
{
if (model.Id == 0)
{
context.Postcodes.Add(model);
}
else
{
var recordToUpdate = context.Postcodes.FirstOrDefault(x => x.Id == model.Id);
if (recordToUpdate != null)
{
recordToUpdate.Suburb = model.Suburb;
recordToUpdate.State = model.State;
recordToUpdate.Postcode = model.Postcode;
recordToUpdate.AuditZoneId = model.AuditZoneId;
recordToUpdate.ModifiedDate = DateTime.Now;
}
}
try
{
context.SaveChanges();
return 1;
}
catch (Exception ex)
{
modelState.AddModelError("", "Database error has occured. Please try again later");
return -1;
}
}
}
Now I know for me to add the code to check to see if there are any changes i need to add it in the try of the save. Before the context.SaveChanges().
But currently I have 10 repos. I don't really want to add code to 10 different places. As this code will do exactly the same thing. I want to somehow have a baseclass that the repos inherit from.
any help? any sample code? any pointers?
would be appreciated. I am sure other people would have done this before
I am mappying my keys, relationships and tables like so
public class AuditZoneMap : EntityTypeConfiguration<AuditZone>
{
public AuditZoneMap()
{
// Primary Key
HasKey(t => t.Id);
// Properties
Property(t => t.Description)
.HasMaxLength(100);
// Table & Column Mappings
ToTable("AuditZone");
Property(t => t.Id).HasColumnName("Id");
Property(t => t.Description).HasColumnName("Description");
Property(t => t.Valid).HasColumnName("Valid");
Property(t => t.CreatedDate).HasColumnName("CreatedDate");
Property(t => t.CreatedBy).HasColumnName("CreatedBy");
Property(t => t.ModifiedDate).HasColumnName("ModifiedDate");
Property(t => t.ModifiedBy).HasColumnName("ModifiedBy");
// Relationships
HasOptional(t => t.CreatedByUser)
.WithMany(t => t.CreatedByAuditZone)
.HasForeignKey(d => d.CreatedBy);
HasOptional(t => t.ModifiedByUser)
.WithMany(t => t.ModifiedByAuditZone)
.HasForeignKey(d => d.ModifiedBy);
}
}
回答1:
What I recommend you is to use the ChangeTracker property in EF.
Inside your DBContext.cs you will have this:
public class DBContext : DbContext
{
public DBContext () : base("DatabaseName")
{
}
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
}
public DbSet<YourPocoModelNameHere > YourPocoModelNameHere { get; set; }
// This is overridden to prevent someone from calling SaveChanges without specifying the user making the change
public override int SaveChanges()
{
throw new InvalidOperationException("User ID must be provided");
}
public int SaveChanges(int userId)
{
// Get all Added/Deleted/Modified entities (not Unmodified or Detached)
foreach (var ent in this.ChangeTracker.Entries().Where(p => p.State == System.Data.EntityState.Added || p.State == System.Data.EntityState.Deleted || p.State == System.Data.EntityState.Modified))
{
// For each changed record, get the audit record entries and add them
foreach (AuditLog x in GetAuditRecordsForChange(ent, userId))
{
this.AuditLogs.Add(x);
}
}
// Call the original SaveChanges(), which will save both the changes made and the audit records
return base.SaveChanges();
}
private List<AuditLog> GetAuditRecordsForChange(DbEntityEntry dbEntry, int userId)
{
List<AuditLog> result = new List<AuditLog>();
DateTime changeTime = DateTime.UtcNow;
// Get the Table() attribute, if one exists
//TableAttribute tableAttr = dbEntry.Entity.GetType().GetCustomAttributes(typeof(TableAttribute), false).SingleOrDefault() as TableAttribute;
TableAttribute tableAttr = dbEntry.Entity.GetType().GetCustomAttributes(typeof(TableAttribute), true).SingleOrDefault() as TableAttribute;
// Get table name (if it has a Table attribute, use that, otherwise get the pluralized name)
string tableName = tableAttr != null ? tableAttr.Name : dbEntry.Entity.GetType().Name;
// Get primary key value (If you have more than one key column, this will need to be adjusted)
var keyNames = dbEntry.Entity.GetType().GetProperties().Where(p => p.GetCustomAttributes(typeof(KeyAttribute), false).Count() > 0).ToList();
string keyName = keyNames[0].Name; //dbEntry.Entity.GetType().GetProperties().Single(p => p.GetCustomAttributes(typeof(KeyAttribute), false).Count() > 0).Name;
if (dbEntry.State == System.Data.EntityState.Added)
{
// For Inserts, just add the whole record
// If the entity implements IDescribableEntity, use the description from Describe(), otherwise use ToString()
foreach (string propertyName in dbEntry.CurrentValues.PropertyNames)
{
result.Add(new AuditLog()
{
AuditLogId = Guid.NewGuid(),
UserId = userId,
EventDateUTC = changeTime,
EventType = "A", // Added
TableName = tableName,
RecordId = dbEntry.CurrentValues.GetValue<object>(keyName).ToString(),
ColumnName = propertyName,
NewValue = dbEntry.CurrentValues.GetValue<object>(propertyName) == null ? null : dbEntry.CurrentValues.GetValue<object>(propertyName).ToString()
}
);
}
}
else if (dbEntry.State == System.Data.EntityState.Deleted)
{
// Same with deletes, do the whole record, and use either the description from Describe() or ToString()
result.Add(new AuditLog()
{
AuditLogId = Guid.NewGuid(),
UserId = userId,
EventDateUTC = changeTime,
EventType = "D", // Deleted
TableName = tableName,
RecordId = dbEntry.OriginalValues.GetValue<object>(keyName).ToString(),
ColumnName = "*ALL",
NewValue = (dbEntry.OriginalValues.ToObject() is IDescribableEntity) ? (dbEntry.OriginalValues.ToObject() as IDescribableEntity).Describe() : dbEntry.OriginalValues.ToObject().ToString()
}
);
}
else if (dbEntry.State == System.Data.EntityState.Modified)
{
foreach (string propertyName in dbEntry.OriginalValues.PropertyNames)
{
// For updates, we only want to capture the columns that actually changed
if (!object.Equals(dbEntry.OriginalValues.GetValue<object>(propertyName), dbEntry.CurrentValues.GetValue<object>(propertyName)))
{
result.Add(new AuditLog()
{
AuditLogId = Guid.NewGuid(),
UserId = userId,
EventDateUTC = changeTime,
EventType = "M", // Modified
TableName = tableName,
RecordId = dbEntry.OriginalValues.GetValue<object>(keyName).ToString(),
ColumnName = propertyName,
OriginalValue = dbEntry.OriginalValues.GetValue<object>(propertyName) == null ? null : dbEntry.OriginalValues.GetValue<object>(propertyName).ToString(),
NewValue = dbEntry.CurrentValues.GetValue<object>(propertyName) == null ? null : dbEntry.CurrentValues.GetValue<object>(propertyName).ToString()
}
);
}
}
}
// Otherwise, don't do anything, we don't care about Unchanged or Detached entities
return result;
}
}
This will use the following table in your DB:
USE [databasename]
GO
/****** Object: Table [dbo].[auditlog] Script Date: 06/01/2014 05:56:49 p. m. ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
SET ANSI_PADDING ON
GO
CREATE TABLE [dbo].[auditlog](
[auditlogid] [uniqueidentifier] NOT NULL,
[userid] [int] NOT NULL,
[eventdateutc] [datetime] NOT NULL,
[eventtype] [char](1) NOT NULL,
[tablename] [nvarchar](100) NOT NULL,
[recordid] [nvarchar](100) NOT NULL,
[columnname] [nvarchar](100) NOT NULL,
[originalvalue] [nvarchar](max) NULL,
[newvalue] [nvarchar](max) NULL,
CONSTRAINT [PK_AuditLog] PRIMARY KEY NONCLUSTERED
(
[auditlogid] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY] TEXTIMAGE_ON [PRIMARY]
GO
SET ANSI_PADDING OFF
GO
ALTER TABLE [dbo].[auditlog] WITH CHECK ADD CONSTRAINT [FK_auditlog_users] FOREIGN KEY([userid])
REFERENCES [dbo].[users] ([userid])
GO
ALTER TABLE [dbo].[auditlog] CHECK CONSTRAINT [FK_auditlog_users]
GO
With this all set then you will just need to call your dbContext.SaveChanges(here the userId);
Hope this will work for you... I use it in all my applications and works great!
Enjoy it.
Full code found here: https://jmdority.wordpress.com/2011/07/20/using-entity-framework-4-1-dbcontext-change-tracking-for-audit-logging/
回答2:
I found this NuGet package (TrackerEnabledDbContext) and followed these 4 steps:
Install package TrackerEnabledDbContext
Inherit my DbContext from TrackerContext in TrackerEnabledDbContext namespace
public class ApplicationDbContext : TrackerContext { public ApplicationDbContext() : base("DefaultConnection") { }
Add a migration and update my database. Two new tables were created for recording changes (AuditLog and AuditLogDetails).
Decide which tables you want to track and apply
[TrackChanges]attribute to the classes. In case you want to skip tracking for some specific columns, you can apply[SkipTracking]attribute to those columns (properties).Whenever you make a change in database, you call
DbContext.SaveChanges(). Now you have an overload available for that which takes an integer. This should be the logged-in person's user ID. If you don't pass the user ID, this change will not be recorded into the tracking table.databaseContext.SaveChanges(userId);
And that's all. Later you can retrieve the logs with this:
var AuditLogs = db.GetLogs<Proyecto>(id).ToList();
回答3:
Disclaimer: I'm the owner of the project Entity Framework Plus
EF+ has auditing features which support EF5, EF6, and EF Core.
// using Z.EntityFramework.Plus; // Don't forget to include this.
var ctx = new EntityContext();
// ... ctx changes ...
var audit = new Audit();
audit.CreatedBy = "ZZZ Projects"; // Optional
ctx.SaveChanges(audit);
// Access to all auditing information
var entries = audit.Entries;
foreach(var entry in entries)
{
foreach(var property in entry.Properties)
{
}
}
A lot of options are available like an AutoSave in the database.
Documentation: EF+ Audit
回答4:
In Generic repository pattern, we can write a generic event handler for db context savechanges event.
I googled it and gathered few many information.
- I dont want to write a sql server trigger
- I dont want to handle savechanges method in each entity.
So i am planning to write generic single method
Db structure that I am using
audit table
CREATE TABLE [dbo].[Audit](
[Id] [BIGINT] IDENTITY(1,1) NOT NULL,
[TableName] [nvarchar](250) NULL,
[Updated By] [nvarchar](100) NULL,
[Actions] [nvarchar](25) NULL,
[OldData] [text] NULL,
[NewData] [text] NULL,
[Created For] varchar(200) NULL,
[Updated Date] [datetime] NULL,
CONSTRAINT [PK_DBAudit] PRIMARY KEY CLUSTERED
(
[Id] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY] TEXTIMAGE_ON [PRIMARY]
2.Update your dbcontext with Audit table entity.
3.Hook generic event handler for Dbcontext savechanges
c# code
namespace ARMS.Domain
{
using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Data;
using System.Data.Objects;
using System.Linq;
using System.Text;
using System.ComponentModel.DataAnnotations;
public partial class ARMSContext
{
Collection<Audit> auditTrailList = new Collection<Audit>();
partial void OnContextCreated()
{
this.SavingChanges += new EventHandler(ArmsEntities_SavingChanges);
}
public enum AuditActions
{
Added,
Modified,
Deleted
}
void ArmsEntities_SavingChanges(object sender, EventArgs e)
{
auditTrailList.Clear();
IEnumerable<ObjectStateEntry> changes =
this.ObjectStateManager.GetObjectStateEntries(
EntityState.Added | EntityState.Deleted | EntityState.Modified);
foreach (ObjectStateEntry stateEntryEntity in changes)
{
if (!stateEntryEntity.IsRelationship && stateEntryEntity.Entity != null && !(stateEntryEntity.Entity is Audit))
{
Audit audit = this.GetAudit(stateEntryEntity);
auditTrailList.Add(audit);
}
}
if (auditTrailList.Count > 0)
{
foreach (var audit in auditTrailList)
{
this.Audits.AddObject(audit);
}
}
}
public Audit GetAudit(ObjectStateEntry entry)
{
Audit audit = new Audit();
audit.Updated_By ="Test";
audit.TableName = entry.EntitySet.ToString();
audit.Updated_Date = DateTime.Now;
audit.Created_For = Convert.ToString(entry.Entity);
audit.Actions = Enum.Parse(typeof(AuditActions),entry.State.ToString(), true).ToString();
StringBuilder newValues = new StringBuilder();
StringBuilder oldValues = new StringBuilder();
if (entry.State == EntityState.Added)
{
SetAddedProperties(entry, newValues);
audit.NewData = newValues.ToString();
}
else if (entry.State == EntityState.Deleted)
{ SetDeletedProperties(entry, oldValues);
audit.OldData = oldValues.ToString();
}
else if (entry.State == EntityState.Modified)
{
SetModifiedProperties(entry, oldValues, newValues);
audit.OldData = oldValues.ToString();
audit.NewData = newValues.ToString();
}
return audit;
}
private void SetAddedProperties(ObjectStateEntry entry, StringBuilder newData)
{
CurrentValueRecord currentValues = entry.CurrentValues;
for (int i = 0; i < currentValues.FieldCount; i++)
{
newData.AppendFormat("{0}={1} || ", currentValues.GetName(i), currentValues.GetValue(i));
}
}
private void SetDeletedProperties(ObjectStateEntry entry, StringBuilder oldData)
{
foreach (var propertyName in entry.GetModifiedProperties())
{
var oldVal = entry.OriginalValues[propertyName];
if (oldVal != null)
{
oldData.AppendFormat("{0}={1} || ", propertyName, oldVal);
}
}
}
private void SetModifiedProperties(ObjectStateEntry entry, StringBuilder oldData, StringBuilder newData)
{
foreach (var propertyName in entry.GetModifiedProperties())
{
var oldVal = entry.OriginalValues[propertyName];
var newVal = entry.CurrentValues[propertyName];
if (oldVal != null && newVal != null && !Equals(oldVal, newVal))
{
newData.AppendFormat("{0}={1} || ", propertyName, newVal);
oldData.AppendFormat("{0}={1} || ", propertyName, oldVal);
}
}
}
}
}
回答5:
Create a class for capture the changes or track the changes when entity added, modifies or deleted.
using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations.Schema;
using System.Data.Entity;
using System.Data.Entity.Infrastructure;
using System.Linq;
using System.Text;
using System.Web;
namespace MVC_AuditTrail.Models
{
public class AuditTrailFactory
{
private DbContext context;
public AuditTrailFactory(DbContext context)
{
this.context = context;
}
public Audit GetAudit(DbEntityEntry entry)
{
Audit audit = new Audit();
// var user = (User)HttpContext.Current.Session[":user"];
audit.UserId = "swapnil";// user.UserName;
audit.TableName = GetTableName(entry);
audit.UpdateDate = DateTime.Now;
audit.TableIdValue = GetKeyValue(entry);
//entry is Added
if (entry.State == EntityState.Added)
{
var newValues = new StringBuilder();
SetAddedProperties(entry, newValues);
audit.NewData = newValues.ToString();
audit.Actions = AuditActions.I.ToString();
}
//entry in deleted
else if (entry.State == EntityState.Deleted)
{
var oldValues = new StringBuilder();
SetDeletedProperties(entry, oldValues);
audit.OldData = oldValues.ToString();
audit.Actions = AuditActions.D.ToString();
}
//entry is modified
else if (entry.State == EntityState.Modified)
{
var oldValues = new StringBuilder();
var newValues = new StringBuilder();
SetModifiedProperties(entry, oldValues, newValues);
audit.OldData = oldValues.ToString();
audit.NewData = newValues.ToString();
audit.Actions = AuditActions.U.ToString();
}
return audit;
}
private void SetAddedProperties(DbEntityEntry entry, StringBuilder newData)
{
foreach (var propertyName in entry.CurrentValues.PropertyNames)
{
var newVal = entry.CurrentValues[propertyName];
if (newVal != null)
{
newData.AppendFormat("{0}={1} || ", propertyName, newVal);
}
}
if (newData.Length > 0)
newData = newData.Remove(newData.Length - 3, 3);
}
private void SetDeletedProperties(DbEntityEntry entry, StringBuilder oldData)
{
DbPropertyValues dbValues = entry.GetDatabaseValues();
foreach (var propertyName in dbValues.PropertyNames)
{
var oldVal = dbValues[propertyName];
if (oldVal != null)
{
oldData.AppendFormat("{0}={1} || ", propertyName, oldVal);
}
}
if (oldData.Length > 0)
oldData = oldData.Remove(oldData.Length - 3, 3);
}
private void SetModifiedProperties(DbEntityEntry entry, StringBuilder oldData, StringBuilder newData)
{
DbPropertyValues dbValues = entry.GetDatabaseValues();
foreach (var propertyName in entry.OriginalValues.PropertyNames)
{
var oldVal = dbValues[propertyName];
var newVal = entry.CurrentValues[propertyName];
if (oldVal != null && newVal != null && !Equals(oldVal, newVal))
{
newData.AppendFormat("{0}={1} || ", propertyName, newVal);
oldData.AppendFormat("{0}={1} || ", propertyName, oldVal);
}
}
if (oldData.Length > 0)
oldData = oldData.Remove(oldData.Length - 3, 3);
if (newData.Length > 0)
newData = newData.Remove(newData.Length - 3, 3);
}
public long? GetKeyValue(DbEntityEntry entry)
{
var objectStateEntry = ((IObjectContextAdapter)context).ObjectContext.ObjectStateManager.GetObjectStateEntry(entry.Entity);
long id = 0;
if (objectStateEntry.EntityKey.EntityKeyValues != null)
id = Convert.ToInt64(objectStateEntry.EntityKey.EntityKeyValues[0].Value);
return id;
}
private string GetTableName(DbEntityEntry dbEntry)
{
TableAttribute tableAttr = dbEntry.Entity.GetType().GetCustomAttributes(typeof(TableAttribute), false).SingleOrDefault() as TableAttribute;
string tableName = tableAttr != null ? tableAttr.Name : dbEntry.Entity.GetType().Name;
return tableName;
}
}
public enum AuditActions
{
I,
U,
D
}
}
Then create audit table entity and context class.
And Override savechanges method in this method get audit changes and save before base entity saved.
using System;
using System.Collections.Generic;
using System.Data.Entity;
using System.Data.Entity.Infrastructure;
using System.Linq;
using System.Web;
namespace MVC_AuditTrail.Models
{
public class Student
{
public int StudentID { get; set; }
public string Name { get; set; }
public string mobile { get; set; }
}
public class Audit
{
public long Id { get; set; }
public string TableName { get; set; }
public string UserId { get; set; }
public string Actions { get; set; }
public string OldData { get; set; }
public string NewData { get; set; }
public Nullable<long> TableIdValue { get; set; }
public Nullable<System.DateTime> UpdateDate { get; set; }
}
public class StdContext : DbContext
{
private AuditTrailFactory auditFactory;
private List<Audit> auditList = new List<Audit>();
private List<DbEntityEntry> objectList = new List<DbEntityEntry>();
public StdContext() : base("stdConnection")
{
Database.SetInitializer<StdContext>(new CreateDatabaseIfNotExists<StdContext>());
}
public DbSet<Student> Student { get; set; }
public DbSet<Audit> Audit { get; set; }
public override int SaveChanges()
{
auditList.Clear();
objectList.Clear();
auditFactory = new AuditTrailFactory(this);
var entityList = ChangeTracker.Entries().Where(p => p.State == EntityState.Added || p.State == EntityState.Deleted || p.State == EntityState.Modified);
foreach (var entity in entityList)
{
Audit audit = auditFactory.GetAudit(entity);
bool isValid = true;
if (entity.State == EntityState.Modified && string.IsNullOrWhiteSpace(audit.NewData) && string.IsNullOrWhiteSpace(audit.OldData))
{
isValid = false;
}
if (isValid)
{
auditList.Add(audit);
objectList.Add(entity);
}
}
var retVal = base.SaveChanges();
if (auditList.Count > 0)
{
int i = 0;
foreach (var audit in auditList)
{
if (audit.Actions == AuditActions.I.ToString())
audit.TableIdValue = auditFactory.GetKeyValue(objectList[i]);
this.Audit.Add(audit);
i++;
}
base.SaveChanges();
}
return retVal;
}
}
}
回答6:
Another option is to create an audit action attribute to allow methods to be decorated with an attribute describing the audit operation. Just inherit from Attribute and list the information you want to capture in the constructor, then create an interceptor (inherit from castle) to intercept request to a method. The interceptor will invoke the audit service (which is just a simple class that will write the audit message to the database).
来源：https://stackoverflow.com/questions/20961489/how-to-create-an-audit-trail-with-entity-framework-5-and-mvc-4