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Adding elements to model space the correct way using .NET API

Method One
_AcDb.Line oLine = new _AcDb.Line(ptStart, ptEnd);
AddToModelSpace("PLOT", oLine);
Where AddToModelSpace is:
public static void AddToModelSpace(string strLayer, _AcDb.Entity oEntity)
{
_AcAp.Document acDoc = _AcAp.Application.DocumentManager.MdiActiveDocument;
_AcDb.Database acCurDb = acDoc.Database;
_AcEd.Editor ed = acDoc.Editor;
using (_AcDb.BlockTable bt = acCurDb.BlockTableId.GetObject(_AcDb.OpenMode.ForRead) as _AcDb.BlockTable)
using (_AcDb.BlockTableRecord ms = bt[_AcDb.BlockTableRecord.ModelSpace].GetObject(_AcDb.OpenMode.ForWrite) as _AcDb.BlockTableRecord)
ms.AppendEntity(oEntity);
oEntity.Layer = strLayer;
oEntity.Dispose();
}
Method Two
// Get the current document and database
_AcAp.Document docActive = _AcAp.Application.DocumentManager.MdiActiveDocument;
_AcDb.Database docDB = docActive.Database;
// Start a transaction
using (_AcDb.Transaction acTrans = docDB.TransactionManager.StartTransaction())
{
// Open the Block table for read
_AcDb.BlockTable acBlkTbl;
acBlkTbl = acTrans.GetObject(docDB.BlockTableId,
_AcDb.OpenMode.ForRead) as _AcDb.BlockTable;
// Open the Block table record Model space for write
_AcDb.BlockTableRecord acBlkTblRec;
acBlkTblRec = acTrans.GetObject(acBlkTbl[_AcDb.BlockTableRecord.ModelSpace],
_AcDb.OpenMode.ForWrite) as _AcDb.BlockTableRecord;
// Create line
using (_AcDb.Line acLine = new _AcDb.Line(ptStart, ptEnd))
{
// Add the new object to the block table record and the transaction
acBlkTblRec.AppendEntity(acLine);
acTrans.AddNewlyCreatedDBObject(acLine, true);
}
// Save the new object to the database
acTrans.Commit();
}
I have used AddToModelSpace in my project so I hope it is fine!

Method Two is the way Autodesk recommends in the developer's documentation (you can read this section).
In Method One, you use the ObjectId.GetObject() method to open the BlockTable and the model space 'BlockTableRecord'. This method uses the top transaction to open object which means that there's an active transaction you should use to add the newly created entity. You can get it with Database.TransactionManager.TopTransaction. If you don't want to use a transaction at all, you have to use the "for advanced use only" ObjectId.Open() method.
A Method Three should be using some extension methods to be called from within a transaction. Here's a simplified (non error checking) extract of the ones I use.
static class ExtensionMethods
{
public static T GetObject<T>(
this ObjectId id,
OpenMode mode = OpenMode.ForRead,
bool openErased = false,
bool forceOpenOnLockedLayer = false)
where T : DBObject
{
return (T)id.GetObject(mode, openErased, forceOpenOnLockedLayer);
}
public static BlockTableRecord GetModelSpace(this Database db, OpenMode mode = OpenMode.ForRead)
{
return SymbolUtilityServices.GetBlockModelSpaceId(db).GetObject<BlockTableRecord>(mode);
}
public static ObjectId Add (this BlockTableRecord owner, Entity entity)
{
var tr = owner.Database.TransactionManager.TopTransaction;
var id = owner.AppendEntity(entity);
tr.AddNewlyCreatedDBObject(entity, true);
return id;
}
}
Using example:
using (var tr = db.TransactionManager.StartTransaction())
{
var line = new Line(startPt, endPt) { Layer = layerName };
db.GetModelSpace(OpenMode.ForWrite).Add(line);
tr.Commit();
}

How to configure an oracle database in apache ignite .NET

I'm trying to configure the write-through and read-through properties of apache Ignite with an Oracle database. I searched in many places like the Ignite oficial documentation, also in the ignite examples on GitHub,
but there isn't much information or examples coded in C# that is the lenguaje in which I'm developing my app.
What I want is to retrieve from a persistent store (in this case an Oracle database), an specific data in the cache (Ignite) that is not already loaded. In a similar way, I need all my changes on the cache to be reflected on the database.
I tied to create and spring.xml with the configuration of the database (ip, port, username, pass, database), but I can't make it work if that is the way it should be done.
Thanks in advance and sorry for my english.

1) Implement ICacheStore interface (or inherit CacheStoreAdapter helper class)
public class OracleStore : CacheStoreAdapter
{
public override object Load(object key)
{
using (var con = new OracleConnection
{
ConnectionString = "User Id=<username>;Password=<password>;Data Source=<datasource>"
})
{
con.Open();
var cmd = con.CreateCommand();
cmd.CommandText = "SELECT * FROM MyTable WHERE ID=#id";
cmd.Parameters.Add("#id", OracleType.Int32);
cmd.Parameters["#id"].Value = key;
using (var reader = cmd.ExecuteReader())
{
// Read data, return as object
}
}
}
public override void Write(object key, object val)
{
oracleDb.UpdateRow(key, val);
}
public override void Delete(object key)
{
oracleDb.DeleteRow(key);
}
}
2) Implement store factory:
public class OracleStoreFactory : IFactory<OracleStore>
{
public OracleStore CreateInstance()
{
return new OracleStore();
}
}
3) Configure cache to use store:
using (var ignite = Ignition.Start())
{
var cacheCfg = new CacheConfiguration
{
ReadThrough = true,
WriteThrough = true,
KeepBinaryInStore = false, // Depends on your case
CacheStoreFactory = new OracleStoreFactory()
};
var cache = ignite.CreateCache<int, MyClass>(cacheCfg);
cache.Get(1); // OracleStore.Load is called.
}
Documentation for Ignite.NET (in C#): https://apacheignite-net.readme.io/docs/persistent-store
C# examples are available in a full download package: https://ignite.apache.org/download.cgi#binaries (click apache-ignite-fabric-1.9.0-bin.zip, download, unzip, open platforms\dotnet\examples\Apache.Ignite.Examples.sln)
Blog post explaining cache store implementation in C#:
https://ptupitsyn.github.io/Entity-Framework-Cache-Store/
Working with Oracle DB in .NET: Connecting to Oracle Database through C#?

Get a list of active session from RedisSessionStateProvider

In my Azure ASP.NET MVC website I want to display how many clients are connected to a Redis sessions state provider and how long they are active. I use the aspnet-redis-providers lib on the Azure Github.
In Redis, it creates a {[app_name]_[sessionkey}_Internal key with a SessionTimeout key with the value of the configured session timeout. The EXPIRE for that key is set to that time and when you check to TTL for the key you see the session access.
How can I use the session state provider library to access this information? If that is not possible, is there any other library I can use to query this info safely, without interfering with the session state provider?

Here is what I was able to do. I created my own session object collection and grabbed all keys (which I am putting in DB 1) then I loop through all keys and grab the TTL.
using StackExchange.Redis;
using StackExchange.Redis.Extensions.Newtonsoft;
using StackExchange.Redis.Extensions.Core;
using System.Linq;
private static Lazy<ConnectionMultiplexer> conn = new Lazy<ConnectionMultiplexer>(
() => ConnectionMultiplexer.Connect(ConfigurationManager.AppSettings["RedisServerMaster"]
+ "," + ConfigurationManager.AppSettings["RedisServerSlave"]
+ "," + ConfigurationManager.AppSettings["RedisOptions"])
public class SessionObjects
{
public string SessionId { get; set; }
public TimeSpan? TTL { get; set; }
}
List<SessionObjects> lso = new List<SessionObjects>();
var serializer = new NewtonsoftSerializer();
StackExchangeRedisCacheClient cacheClient;
cacheClient = new StackExchangeRedisCacheClient(rConn, serializer, 1);
IEnumerable<string> keys = cacheClient.SearchKeys("*");
var db = rConn.GetDatabase(1);
foreach (var s in keys)
{
SessionObjects so = new SessionObjects();
so.SessionId = s;
so.TTL = db.KeyTimeToLive(s);
lso.Add(so);
}

Entity Framework + MySQL: BLOB/TEXT column 'Hash' used in key specification without a key length

I'm trying to use Entity Framework with MySQL. I've just installed MySQL Installer for Windows which includes MySQL Connector for .NET.
I can't find any documentation on how to actually use this thing, so I've been cobbling pieces together from various tutorials. It appears I need the references for MySql.Data and MySql.Data.Entity for EF6 (screenshot).
Then I stole this source code from some random project which is the only reference I could find to MySqlConnectionFactory:
class ImgSigDbConfig : DbConfiguration
{
public ImgSigDbConfig()
{
base.AddDependencyResolver(new MySqlDependencyResolver());
base.SetProviderFactory(MySqlProviderInvariantName.ProviderName, new MySqlClientFactory());
base.SetProviderServices(MySqlProviderInvariantName.ProviderName, new MySqlProviderServices());
base.SetDefaultConnectionFactory(new MySqlConnectionFactory());
base.SetMigrationSqlGenerator(MySqlProviderInvariantName.ProviderName, () => new MySqlMigrationSqlGenerator());
base.SetProviderFactoryResolver(new MySqlProviderFactoryResolver());
base.SetManifestTokenResolver(new MySqlManifestTokenResolver());
}
}
I couldn't figure out how to set my database credentials anywher ein there, but apparently you can pass them in when constructing the DbContext:
Database.SetInitializer(new DropCreateDatabaseIfModelChanges<ImgSimContext>());
var conn = new MySqlConnectionStringBuilder
{
Server = "localhost",
UserID = "root",
Password = "pass",
Database = "ImgSig"
};
using (var db = new ImgSimContext(conn.ToString()))
{
SqlConnection.ClearAllPools();
db.Database.Initialize(force: true);
Now I've created a very simple POCO:
internal class ImgSig
{
[Key, Required]
public int Id { get; set; }
[Index, StringLength(16), Required]
public byte[] Hash { get; set; }
}
But when it hits db.Database.Initialize an exception is thrown:
BLOB/TEXT column 'Hash' used in key specification without a key length
Which makes perfect sense because in MySQL you have to set the key length for any blob/text fields (although it would be nice to see what SQL it's trying to run).
So my questions are:
How can I change the data type of Hash to a fixed length binary(16)?
How can I set the key length (preferably using attributes)?

How to change db connection programmatically c# Entity Framework

I've built my project and named the db connection "VMaxEntities"
The connection string exists in web.config.
I have another connection string "Development_VMaxEntities"
Whenever I call the db, I use the code using (VMaxEntities db = new VMaxEntities())
This calls:
public partial class VMaxEntities : DbContext
{
public VMaxEntities()
: base("name=VMaxEntities")
{
}
What I want to do is connect to a development database instead of the live one, IF the current URI contains localhost.
So - thanks to cgotberg's answer below, here's what I used to get it working: (note, I add the password here instead of in web.config)
public VMaxEntities()
: base("name=Secure_VMaxEntities")
{
if (System.Web.HttpContext.Current.Request.Url.Host == "localhost")
{
var connectionString = this.Database.Connection.ConnectionString + ";password=***********";
this.Database.Connection.ConnectionString = connectionString.Replace("catalog=VMax", "catalog=DEV_VMax");
}
else
{
this.Database.Connection.ConnectionString += ";password=************";
}
}

I've done something like this in the past
using(var db = new VMaxEntities())
{
var connectionString = context.Database.Connection.ConnectionString;
var datasource = context.Database.Connection.DataSource;
var databaseServer = "yourDevDatabaseServerName"
db.Database.Connection.ConnectionString = connectionString.Replace(datasource, databaseServer);
}