Is it possible to get the connection string from an AppService? I want to use Dapper directly as below:
using (IDbConnection db = new SqlConnection(_connString))
{
//My code here
}
Can I get _connString from AppService?
there's a Dapper integration of ABP.
install Dapper from Nuget
https://www.nuget.org/packages/Abp.Dapper
And read the doc https://aspnetboilerplate.com/Pages/Documents/Dapper-Integration
if you still want to get a connection string you can get from config
ConfigurationManager.ConnectionStrings["Default"];
or you can create a custom repository and get it from DbContext
Related
I'm having a lot of trouble getting a basic proof-of-concept working, in which I am accessing an Oracle DB (11g) through Azure Functions via Entity Framework (6.2).
Prerequisites:
ODT For Visual Studio 2017 is installed, as well as Azure Functions CLI/Core Tools. Everything mentioned below is done entirely via Visual Studio 2017, not through Azure portal.
Take 1:
Created a new project with the Azure Functions template.
Installed NuGet packages EntityFramework (6.2.0), Oracle.ManagedDataAccess (12.2.1100) and Oracle.ManagedDataAccess.EntityFramework (12.2.1100). Note: When installing NuGet packages in projects using the Azure Functions template, the packages are added under Dependencies -> NuGet, rather than under References.
Added ADO.NET Entity Data Model to project.
Problem: After setting my connection string, choosing Entity Framework 6.x is unavailable, with the following error message:
An Entity Framework database provider compatible with the latest
version of Entity Framework could not be found for your data
connection. If you have already installed a compatible provider,
ensure you have rebuilt your project before performing this action.
Otherwise, exit this wizard, install a comaptible provider, and
rebuild your project befre performing this action.
As the simplest of workarounds, I have tried to just go ahead with EF5, but it throws an exception while creating the DB model (after selecting the objects to include in model, including some stored procedures).
Take 2:
Created project and installed NuGet packages as above.
Created class library project to facilitate the Oracle interactions.
Installed the same NuGet packages as above in the class library project.
Added ADO.NET Entity Data Model to class library project and added some database objects to the database model. Also added custom constructor to the model for specific connection string, because managing connection strings in Azure Functions was a seperate set of headaches that I'll deal with later.
Added a simple wrapper method to the class library project that calls a stored procedure from the database model:
public static string NameByEmpNo(int empNo)
{
string result;
MyEntities entities = new MyEntities("metadata=res://*/MyEntities.csdl|res://*/MyEntities.ssdl|res://*/MyEntities.msl;provider=Oracle.ManagedDataAccess.Client;provider connection string='DATA SOURCE=127.0.0.1:1521/ORCL;PASSWORD=tiger;USER ID=SCOTT'");
ObjectParameter name = new ObjectParameter("o_empname", typeof(string));
entities.GET_EMP_NAME_PROC(empNo, name);
result = (string)name.Value;
return result;
}
Added reference to the class library in the Azure Functions project.
Added function that calls NameByEmpNo:
[FunctionName("GetNameByEmpNo")]
public static async Task<HttpResponseMessage> GetNameByEmpNo([HttpTrigger(AuthorizationLevel.Function, "get", Route = null)]HttpRequestMessage req, TraceWriter log)
{
int empNo = Int32.Parse(req.GetQueryNameValuePairs()
.FirstOrDefault(q => string.Compare(q.Key, "empno", true) == 0)
.Value);
string empName = ScottAccess.NameByEmpNo(empNo);
return req.CreateResponse(HttpStatusCode.OK, "Employee name: " + empName);
}
Problem: At runtime, calling the function fails with this error
message:
Exception while executing function: GetNameByEmpNo -> The ADO.NET
provider with invariant name 'Oracle.ManagedDataAccess.Client' is
either not registered in the machine or application config file, or
could not be loaded. See the inner exception for details. -> Unable to
find the requested .Net Framework Data Provider. It may not be
installed.
Bonus info: My class library works perfectly when called through a console application. Also, my Azure Functions app works perfectly when calling functions that do not use my class library...
I am stumped. Has anyone got experience with getting this combination of techs working together and can offer some insight into where I'm going wrong / provide steps to get a basic connection working?
Entity Framework within Azure Functions defaults the providers to System.Data.SqlClient so SQL connections will work without any configuration changes, but that means you have to do something special for Oracle connections. The problem seems to come from the config values that the Oracle.ManagedDataAccess.Client library assumes are available within the App.Config or Web.Config file in the project, which are inserted whenever you install the Oracle.ManagedDataAcess.EntityFramework Nuget package. Azure Functions don't have config files, and I wasn't able to find any way to specify the Oracle provider in the settings json files.
I found a solution in this post
It suggests bypassing this mechanism and creating a DbConfiguration for Oracle, then using DbConfigurationType to tell the DbContext which configuration you're using.
public class OracleDbConfiguration : DbConfiguration
{
public OracleDbConfiguration()
{
SetDefaultConnectionFactory(new OracleConnectionFactory());
SetProviderServices("Oracle.ManagedDataAccess.Client", EFOracleProviderServices.Instance);
SetProviderFactory("Oracle.ManagedDataAccess.Client", new OracleClientFactory());
}
}
[DbConfigurationType(typeof(OracleDbConfiguration))]
public partial class MyEntities : IGISContext
{
//Expose Connection String Constructor
public MyEntities(string connectionString, int commandTimeoutInSeconds = 30) : base(connectionString)
{
this.Database.CommandTimeout = commandTimeoutInSeconds;
}
}
Note: I used EF 6 Database First to generate my EDMX; MyEntities here is a partial class for providing a constructor that takes in a connection string.
The oracle connection wil use the specified DbConfiguration class, and any SQL database connections will continue to work using the defaults.
My solution is using the Nuget Packages:
EntityFramework 6.2.0
Oracle.ManagedDataAccess 12.2.1100
Oracle.ManagedDataAccess.EntityFramework 12.2.1100
I'd like to connect to Oracle Database using Sahi 5.0 OS API:
var $db = _getDB($driver, $jdbcurl, $username, $password)
or
var $db = _getDB("oracle.jdbc.driver.OracleDriver",
"jdbc:oracle:thin:#dbserver:1521:sid",
"username", "password");
I have downloaded classes12.jar and ojdbc14.jar and put it in C:\Users\Username\sahi\extlib\db
I've also already added in dashboard.bat:
set SAHI_CLASS_PATH=%SAHI_HOME%\lib\sahi.jar;
%SAHI_HOME%\extlib\rhino\js.jar;%SAHI_HOME%\extlib\apc\commons-codec-1.3.jar;
%SAHI_HOME%\extlib\db\ojdbc14.jar;%SAHI_HOME%\extlib\db\classes12.jar
and in dashboard.sh:
SAHI_CLASS_PATH=$SAHI_HOME/lib/sahi.jar:$SAHI_HOME/extlib/rhino/js.jar:
$SAHI_HOME/extlib/apc/commons-codec-1.3.jar:
$SAHI_HOME/extlib/db/ojdbc14.jar:$SAHI_HOME/extlib/db/classes12.jar
However if I try use 1st method to use _getDB i've following result:
Java constructor for "net.sf.sahi.plugin.DBClient"
with arguments "string,string,string,string" not found.
When I use second one I have this:
Java constructor for "net.sf.sahi.plugin.DBClient"
with arguments "string,string,java.util.Properties" not found.
How connect I connect to Oracle DB and use methods like $db.select and $db.update?
I'm working on Windows 7 with JDK 1.8
I think I can help you.
Was also getting errors when trying to connect to a database with Sahi OS.
The examples shown in https://sahipro.com/docs/sahi-apis/database-apis.html page are useful, but I believe there is more to the SAHI Pro.
Because I said it above?
I tried a number of ways and was not loading the database. Another problem is that I was trying to insert and not recover data.
I began to analyze the obtained error (same as yours) and then found that the SAHI API, this class 'net.sf.sahi.plugin.DBClient', there is the constructor method in the class, the _getDb function () calls to start the object.
Concludes that it found the SAHI API available on Github and checked by the class.
There is no method builder, this function does not work for SAHI OS.
So we have to do this using functions of the JAVA language, as is the example: https://sahipro.com/docs/sahi-apis/database-apis.html#Accessing%20databases%20directly
I modified this function (as I said, I was entering in the database) to my need, which was inserted into the database and vualá !!!! It worked!
I used SQLite (the SAHI documentation contains no example)
To clarify, the function I created would be this:
function setRawDB(driverName, jdbcurl, sqlQuery) {
java.lang.Class.forName(driverName);
var connection = java.sql.DriverManager.getConnection(jdbcurl);
var stmt = connection.createStatement();
var query = stmt.executeUpdate(sqlQuery);
stmt.close();
//sahi auto commit
//connection.commit();
connection.close();
}
and then I got to use automated scripts (before I was just getting used testing directly on the page), saving directly in the local database.
Only in this way could use.
In my gwt web-app i'm using Mondrian. I have a method:
private Result executeMdxQuery(String queryString, Schema schema) throws InterruptedException {
CatalogLocatorImpl locator = new CatalogLocatorImpl();
Connection mdxConnection = DriverManager.getConnection(createConnectString(schema), locator);
return executeMdxQuery(queryString, mdxConnection);
}
result of createConnectString(schema) is
Provider=mondrian;Jdbc=jdbc:mysql://localhost/dds?user=root&password=qwerty;Catalog=/home/vskovalenko/schemas/air_new_zealand_monthly_traffic.xml;JdbcDrivers=com.mysql.jdbc.Driver;
all data within it is seems to be correct (at least db credentials and path to the file), this method throws no exception, it just silently dies and doesn't tell anything. Where should i loock to?
You should use the olap4j API to get a connection. This will allow you to let the application server manage and pool the connections to Mondrian.
If you require more control on the Mondrian server instance, you should take a look at the class MondrianServer.
add the following snippet to your code and try again:
Class.forName("mondrian.olap4j.MondrianOlap4jDriver");
My scenario is this:
I have a custom RavenDB membership provider that is implemented in a class library (DLL). This provider needs to access a database to store and retrieve User and Role information. I'd like to use the same app database to store membership information to avoid having one more database.
I don't know how to get a reference to the already initialized database (app database) inside the class library code. I think I'm going the wrong way here... :)
Some code:
bool embeddedStore = Convert.ToBoolean(config["enableEmbeddableDocumentStore"]);
if (embeddedStore)
{
_documentStore = new EmbeddableDocumentStore()
{
// Here I'm using the same connection string used by the app.
// This gives me an error when I try to open a session in the DocumentStore.
ConnectionStringName =
config["connectionStringName"]
};
}
else
{
_documentStore = new DocumentStore()
{
ConnectionStringName =
config["connectionStringName"]
};
}
This is the connection string present in Web.config:
<add name="RavenDB" connectionString="DataDir = ~\App_Data\Database" />
How can I reuse the same database within the custom membership provider? Any ideas?
I thought about moving the class library code files to the Web project. This way I could get a reference to the DocumentStore easily, but the code wouldn't be as organized as I'd like.
I also tried to use 2 RavenDB databases: 1 for the app and 1 for the membership provider, but as I'm running RavenDB in its embeddable fashion I couldn't get it working.
These are the errors I got during my attempts so far:
RavenDB Could not open transactional storage.
Temp path already used by another database instance.
You need to pass the instance of the opened document store to your dll.
You can do that using a container or by providing an API call to do that.
You can't have two instance using the same db.
I've set up a db4o server and client. My client calls are not working.
What's puzzling to me is that the db4o examples show how the client can close the server, but not how to get and save data. See: http://community.versant.com/Documentation/Reference/db4o-7.12/java/reference/Content/client-server/networked/simple_db4o_server.htm
If I start the db4o server, and run netstat, I can see that the port is open. And on the client, I can do things like this:
Debug.WriteLine(db.Ext().IsClosed().ToString());
And that returns False, which is good.
But when I try to get or save data, it doesn't work. When saving data, it appears to work, but I don't see the data in the DB. When trying to retrieve the object, I get this error:
Db4objects.Db4o.Ext.Db4oException: Exception of type 'Db4objects.Db4o.Ext.Db4oException' was thrown. ---> System.ArgumentException: Field '_delegateType' defined on type 'Db4objects.Db4o.Internal.Query.DelegateEnvelope' is not a field on the target object which is of type 'Db4objects.Db4o.Reflect.Generic.GenericObject'.
Here are the client calls to save, then get:
Server server = new Server() { Name = "AppServerFoo" };
IObjectContainer db = GetDatabase();
db.Store(server);
db.Close();
Here's the only line in the GetDatabase() method:
return Db4oClientServer.OpenClient(Db4oClientServer.NewClientConfiguration(), "DellXps", 8484, "user", "password");
And here's the call to get from the DB:
IObjectContainer db = GetDatabase();
Server testServer = db.Query<Server>(server => server.Name == "AppServerFoo").FirstOrDefault();
db.Close();
What am I missing?
Well a server without a reference the persisted classes is a 'risky' thing. A lot of functionally doesn't work and the error which occur are cryptic. I highly recommend to always reference the assembly with the persisted classes on the server.
Another tip: Use LINQ instead of native queries. It works better and has less problems.
A ha! I got it. It took some googling, but the problem was that the server didn't have a reference to the entities. As soon as my server project referenced my client project, it worked. So, it looks like I just need to move my entities to a common project that both the client and server can reference.
Thanks to this link:
http://www.gamlor.info/wordpress/2009/11/db4o-client-server-and-concurrency/
This link looks like a gateway to having the server work without referencing the entities:
http://community.versant.com/Documentation/Reference/db4o-7.12/net2/reference/html/reference/client-server/server_without_persistent_classes_deployed.html