StructureMap 2.5.3 in .Net 4.5.2 Lazy Loading Question - c#

We are stuck back in StructureMap 2.5.3, running on .Net 4.5.2. I'm writing an app using our Libs that
needs to startup and login using local data, and not hit the DB.
In our BootStrap StructureMap Calls, we Create a named object for the DB access classes like this
// need one for ADO for JCDC
x.BuildInstancesOf()
.AddInstances( z => z
.OfConcreteType()
.WithName( "JCDC" )
.SetProperty( y => y.ConnectStringName = "SybaseDB" )
.SetProperty( y => y.TimeOutStringName = "SybaseDBCommandTimeout" )
);
How do I Make this load Lazily?
I know there is in .net 4 and Func before that, and I've found simple examples
of how to use it, but I haven't wrapped my head around how to get the above code to load lazily
(When structure map inits it , it immediately connect to the DB, which fails offline)

Related

PostgreSQL Log - parameter details [duplicate]

Is there a way to dump the generated sql to the Debug log or something? I'm using it in a winforms solution so the mini-profiler idea won't work for me.
I got the same issue and implemented some code after doing some search but having no ready-to-use stuff. There is a package on nuget MiniProfiler.Integrations I would like to share.
Update V2: it supports to work with other database servers, for MySQL it requires to have MiniProfiler.Integrations.MySql
Below are steps to work with SQL Server:
1.Instantiate the connection
var factory = new SqlServerDbConnectionFactory(_connectionString);
using (var connection = ProfiledDbConnectionFactory.New(factory, CustomDbProfiler.Current))
{
// your code
}
2.After all works done, write all commands to a file if you want
File.WriteAllText("SqlScripts.txt", CustomDbProfiler.Current.ProfilerContext.BuildCommands());
Dapper does not currently have an instrumentation point here. This is perhaps due, as you note, to the fact that we (as the authors) use mini-profiler to handle this. However, if it helps, the core parts of mini-profiler are actually designed to be architecture neutral, and I know of other people using it with winforms, wpf, wcf, etc - which would give you access to the profiling / tracing connection wrapper.
In theory, it would be perfectly possible to add some blanket capture-point, but I'm concerned about two things:
(primarily) security: since dapper doesn't have a concept of a context, it would be really really easy for malign code to attach quietly to sniff all sql traffic that goes via dapper; I really don't like the sound of that (this isn't an issue with the "decorator" approach, as the caller owns the connection, hence the logging context)
(secondary) performance: but... in truth, it is hard to say that a simple delegate-check (which would presumably be null in most cases) would have much impact
Of course, the other thing you could do is: steal the connection wrapper code from mini-profiler, and replace the profiler-context stuff with just: Debug.WriteLine etc.
You should consider using SQL profiler located in the menu of SQL Management Studio → Extras → SQL Server Profiler (no Dapper extensions needed - may work with other RDBMS when they got a SQL profiler tool too).
Then, start a new session.
You'll get something like this for example (you see all parameters and the complete SQL string):
exec sp_executesql N'SELECT * FROM Updates WHERE CAST(Product_ID as VARCHAR(50)) = #appId AND (Blocked IS NULL OR Blocked = 0)
AND (Beta IS NULL OR Beta = 0 OR #includeBeta = 1) AND (LangCode IS NULL OR LangCode IN (SELECT * FROM STRING_SPLIT(#langCode, '','')))',N'#appId nvarchar(4000),#includeBeta bit,#langCode nvarchar(4000)',#appId=N'fea5b0a7-1da6-4394-b8c8-05e7cb979161',#includeBeta=0,#langCode=N'de'
Try Dapper.Logging.
You can get it from NuGet. The way it works is you pass your code that creates your actual database connection into a factory that creates wrapped connections. Whenever a wrapped connection is opened or closed or you run a query against it, it will be logged. You can configure the logging message templates and other settings like whether SQL parameters are saved. Elapsed time is also saved.
In my opinion, the only downside is that the documentation is sparse, but I think that's just because it's a new project (as of this writing). I had to dig through the repo for a bit to understand it and to get it configured to my liking, but now it's working great.
From the documentation:
The tool consists of simple decorators for the DbConnection and
DbCommand which track the execution time and write messages to the
ILogger<T>. The ILogger<T> can be handled by any logging framework
(e.g. Serilog). The result is similar to the default EF Core logging
behavior.
The lib declares a helper method for registering the
IDbConnectionFactory in the IoC container. The connection factory is
SQL Provider agnostic. That's why you have to specify the real factory
method:
services.AddDbConnectionFactory(prv => new SqlConnection(conStr));
After registration, the IDbConnectionFactory can be injected into
classes that need a SQL connection.
private readonly IDbConnectionFactory _connectionFactory;
public GetProductsHandler(IDbConnectionFactory connectionFactory)
{
_connectionFactory = connectionFactory;
}
The IDbConnectionFactory.CreateConnection will return a decorated
version that logs the activity.
using (DbConnection db = _connectionFactory.CreateConnection())
{
//...
}
This is not exhaustive and is essentially a bit of hack, but if you have your SQL and you want to initialize your parameters, it's useful for basic debugging. Set up this extension method, then call it anywhere as desired.
public static class DapperExtensions
{
public static string ArgsAsSql(this DynamicParameters args)
{
if (args is null) throw new ArgumentNullException(nameof(args));
var sb = new StringBuilder();
foreach (var name in args.ParameterNames)
{
var pValue = args.Get<dynamic>(name);
var type = pValue.GetType();
if (type == typeof(DateTime))
sb.AppendFormat("DECLARE #{0} DATETIME ='{1}'\n", name, pValue.ToString("yyyy-MM-dd HH:mm:ss.fff"));
else if (type == typeof(bool))
sb.AppendFormat("DECLARE #{0} BIT = {1}\n", name, (bool)pValue ? 1 : 0);
else if (type == typeof(int))
sb.AppendFormat("DECLARE #{0} INT = {1}\n", name, pValue);
else if (type == typeof(List<int>))
sb.AppendFormat("-- REPLACE #{0} IN SQL: ({1})\n", name, string.Join(",", (List<int>)pValue));
else
sb.AppendFormat("DECLARE #{0} NVARCHAR(MAX) = '{1}'\n", name, pValue.ToString());
}
return sb.ToString();
}
}
You can then just use this in the immediate or watch windows to grab the SQL.
Just to add an update here since I see this question still get's quite a few hits - these days I use either Glimpse (seems it's dead now) or Stackify Prefix which both have sql command trace capabilities.
It's not exactly what I was looking for when I asked the original question but solve the same problem.

Connecting to mongodb sing C# quick tour not creating db or collection

I'm going through the mongoDB Driver Documentation Quick Tour for the first time. Specifically the 2.4 version.
I've created a fresh mongodb instance at the 192.168.1.50 address, and it appears to be running correctly.
The MongoDB documentation gives the following example:
var client = new MongoClient("mongodb://192.168.1.50:27017");
#It's ok if the database doesn't yet exist. It will be created upon first use
var database = client.GetDatabase("testDB");
#It’s ok if the collection doesn’t yet exist. It will be created upon first use.
var collection = database.GetCollection<BsonDocument>("testCollection");
However, when I go on my server, and I enter the mongo console
mongo
And I list the databases using
show dbs
The output is only
admin 0.000GB
local 0.000GB
Is there anything else I should have done to make this work? I'm getting no errors on try/catch, and it appears to be running fine.
Troubleshooting
So far I've confirmed that mongodb is running by using the following:
netstat -plntu
Shows mongod running on 27017 in the LISTEN state.
I'd also be interested in knowing if there's a way on the mongodb server to view live connections, so I could see if it were actually successfully connecting.
Well the problem is that you need to create almost one collection in order to persist the created database (weird right?) i tested it with robomongo and works in that way.
The problem is that GetCollection method is not creating the target collection, you can try with this code:
static void Main(string[] args)
{
var client = new MongoClient("mongodb://192.168.1.50:27017");
//# It's ok if the database doesn't yet exist. It will be created upon first use
var database = client.GetDatabase("test");
//# It’s ok if the collection doesn’t yet exist. It will be created upon first use.
string targetCollection = "testCollection";
bool alreadyExists = database.ListCollections().ToList().Any(x => x.GetElement("name").Value.ToString() == targetCollection);
if (!alreadyExists)
{
database.CreateCollection(targetCollection);
}
var collection = database.GetCollection<BsonDocument>(targetCollection);
}
It turns out that a method I had found on how to set multiple bindIp's was incorrect. The problem wasn't with the C# at all. I found the solution here
In case that ever goes away, here's the current settings I had to follow for multiple ip's
edit file /etc/mongod.conf
Wrap the comma-separated-Ips with brackets
bindIp = [127.0.0.1, 192.168.184.155, 96.88.169.145]
My original code worked fine, I just didn't have the brackets on the bindIp.

JINT - Unable to "console.log"

I am new to JINT, and trying to just do some basic tests to kind of learn the ropes. My first attempt was to just store some javascript in my database, load it, and execute it in a unit test. So that looks essentially like this....
[Fact]
public void can_use_jint_engine() {
using (var database = DocumentStore()) {
using (var session = database.OpenSession()) {
var source = session.Load<Statistic>("statistics/1");
// join the list of strings into a single script
var script = String.Join("\n", source.Scripting);
// this will create the script
// console.log("this is a test from jint.");
//
var engine = new Jint.Engine();
// attempt to execute the script
engine.Execute(script);
}
}
}
And it doesn't work, I get this error, which makes absolutely no sense to me, and I cannot find any documentation on.
Jint.Runtime.JavaScriptExceptionconsole is not defined at
Jint.Engine.Execute(Program program) at
Jint.Engine.Execute(String source) at
SampleProject.Installers.Instanced.__testing_installer.can_use_jint_engine()
in _testing_installer.cs: line 318
Can anyone assist in shedding some light on this? I'm pretty confused at this point.
With JavaScript there are three entities - we care about. The host (browser, your application etc), the engine (JINT in this case) and the script ("console.log(...)") in this case.
JavaScript defines a bunch of functions and object as part of the language, but console is not one of them. By convention, browsers define a console object that can be used in the manner you describe. However, since your app is not a browser (and JINT does not do this by itself), there's no console object defined in your namespace (globals).
What you need to do is add a console object that will be accessible in JINT. You can find how to do this in the docs, but here's a simple example of how to add a log function to the engine so it can be used from the JS code (example taken from github).
var engine = new Engine()
.SetValue("log", new Action<object>(Console.WriteLine))
;
engine.Execute(#"
function hello() {
log('Hello World');
};
hello();
");

Entity Framework, SQLite and Lazy loading

Hi I had developed a C# Budget application using SQL Compact and EF4, I created the EF model through the VS2010 Entity Data Model template. It is all working very well. However I am considering developing a iPhone app to support cash transactions and thought it would be better to have the back end DB supported on both platforms. After creating the SQLite DB and creating a new model I have come across a problem when trying to access referenced data via the Navigation properties in my model. I am getting a NullReferenceException when trying to display a property of a referenced table.
When using the following code I get the exception on the last line:
BudgetEntities budget = new BudgetEntities();
var accounts = budget.BankAccounts.ToList();
foreach (BankAccount a in accounts)
{
Console.WriteLine("Name:" + a.Description);
Console.WriteLine("Number:" + a.AccountNumber);
Console.WriteLine("Type:" + a.BankAccountType.AccountType); //Exception occurs here.
}
Strange thing is that the exception doesn't occur in this example. I'm not sure what is going on?
BudgetEntities budget = new BudgetEntities();
var accoutTypes = budget.BankAccountTypes;
var account = new BankAccount();
account.ID = Guid.NewGuid();
account.AccountTypeID = accoutTypes.First(t => t.AccountType.StartsWith("Credit")).ID;
account.BSB = "3434";
account.AccountNumber = "32323";
account.Description = "Test";
account.TrackingAccount = true;
budget.AddObject("BankAccounts", account);
budget.SaveChanges();
var accounts = budget.BankAccounts.ToList();
foreach (BankAccount a in accounts)
{
Console.WriteLine("Name:" + a.Description);
Console.WriteLine("Number:" + a.AccountNumber);
Console.WriteLine("Type:" + a.BankAccountType.AccountType); //Exception doesn't happen.
}
This is only a simple example and I know I could fix it by adding .Include("BankAccountTypes") to the query however I have other queries that are quite complex that are creating object which include properties from referenced object with in the query and I am not quite sure how to get around this issue for them.
EDIT:
After having a break between projects I have come back to this problem and I have finally resolved my problem. it had nothing to do with the code. It was with the data. I had converted a SQL Compact database to SQLite via a dump and load and had the syntax wrong for my Guid column data. I was inserting the Guid as '7cee3e1c-7a2b-462d-8c3d-82dd6ae62fb4' when it should have been x'7cee3e1c7a2b462d8c3d82dd6ae62fb4'
Hopefully the hair I pulled out working through this problem will grow back :)
Thanks everyone for your input.
In second example your code snippet begins with:
var accoutTypes = budget.BankAccountTypes;
This loads all bank account types to your application and you don't need lazy loading anymore (EF will automatically recognize that these entities were already loaded and fix relations with bank accounts).
First check if your account class is dynamic proxy (just check type of a in the debugger). If it is not you made some mistake in the class definition and lazy loading will not work. Next check if lazy loading is enabled on your context instance (budget.ContextOptions.LazyLoadingEnabled property).
Make sure the BankAccountType property is declared virtual in BudgetEntities.

vmware .net api help vmware.vim.dll problems

Vmware's .net api reference is somewhat confusing and hard to follow. I have been able to connect to my vcenter host then get a list of esxi hosts. Then I have been able get all the running modules on the host using HostKernelModuleSystem, and probe the properties on the variable "mod"... but I am not able to figure out how to get license info, I tried creating an object lic below, trying all different kinds of "types" from vmware with the word license in the type. but, it never works it has a problem converting the line with LicenseManagerLicenseInfo lic = .... I always get the following:
"Cannot convert type 'Vmware.Vim.Viewbase' to
'Vmware.Vim.LicenseManagerLicenseInfo'"
but the declaration above it for "mod" works fine.
I have also tried:
HostLicenseConnectInfo
LicenseAssignmentManagerLicenseAssignment
LicenseManager
I am hoping someone who has worked with vmware .net api can shed some light on what i am doing wrong? I am new to C# about 1 year :) but these VMware APIs are somewhat confusing to me.
esxList = client.FindEntityViews(typeof(HostSystem), null, null, null);
foreach (HostSystem host in esxList)
{
HostKernelModuleSystem mod = (HostKernelModuleSystem)client.GetView(host.ConfigManager.KernelModuleSystem, null);
LicenseManagerLicenseInfo lic = (LicenseManagerLicenseInfo)client.GetView(host.ConfigManager.LicenseManager, null);
string name = lic.Name;
}
I'll have to go to work tomorrow to look at this ( don't have ESX and VMWare SDK for .NET at home ) but I've done a bit of this work.
I wrote a generics method that wraps FindEntityViews and takes a filter as an argument. That makes it easy to search for anything. Also I've noticed that searches come back as ManagedObjectReferences and can't be cast to the subclasses. You have to construct them passing the ManagedObjectReference as an argument.
Also I find searching for PowerCLI examples and watching the classes in the immeadiate window very help in navigating this API. It's a fairly decent SDK but they put all of the classes in a single namespace and there's lots of little style inconsistencies ( Device instead of Devices and properties that take strings instead of enums when an enum exists ).
i figured out how to do it :) , by using http://vcenter_hostname/mob I was able to walk through api better. here is what I did, plus instead of of using "host" which was type HostSystem I jused my instance of my vCenter host "client"
VMware.Vim.LicenseManager lic_manager = (VMware.Vim.LicenseManager)client.GetView(client.ServiceContent.LicenseManager, null);
LicenseManagerLicenseInfo[] lic_found = lic_manager.Licenses;
foreach (LicenseManagerLicenseInfo lic in lic_found)
{
string test = lic.Name.ToString();
string test2 = lic.LicenseKey.ToString();
}

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