Customize DbContext using connection string from ServiceConfiguration (Azure)

Question

I am using the entity-framework with Code First approach and I have a custom DbContext. My connectionstring is defined in the ServiceConfiguration.Cloud.cscfg and ServiceConfiguration.Local.cscfg files.

 public CustomContext()
                : base("dbActivity")
 {
    ...

When the above code executes, it tries to check my web.config and not the ServiceConfiguration file from an azure solution.

UPDATE: Here is my connectionString in the ServiceConfiguration file:

<ConfigurationSettings>
  <Setting name="Microsoft.WindowsAzure.Plugins.Diagnostics.ConnectionString" value="UseDevelopmentStorage=true" />
  <Setting name="dbActivity" value="Server=tcp:xxx.database.windows.net,1433;Database=ra;User ID=user;Password=password;Trusted_Connection=False;Encrypt=True;Connection Timeout=30;" />
</ConfigurationSettings>

Exception:

No connection string named 'Server=tcp:xxx.database.windows.net,1433;Database=ra;User ID=user;Password=password;Trusted_Connection=False;Encrypt=True;Connection Timeout=30;' could be found in the application config file."

Is it possible to make it check the ServiceConfiguration.Local.cscfg instead?

possible duplicate of [Configure Entity Framework to pick connection strings from Azure CloudConfiguration File?](http://stackoverflow.com/questions/24222862/configure-entity-framework-to-pick-connection-strings-from-azure-cloudconfigurat) — Abhijeet, Oct 10 '14 at 12:52

score 2 · Accepted Answer · answered Nov 03 '14 at 10:47

Finally I found the solution. It's necessary to use the SqlConnectionStringBuilder class.

public RAActivityContext()
    : base((new SqlConnectionStringBuilder(
            CloudConfigurationManager.GetSetting("dbRAActivity")).ToString()))
{            

}

score 0 · Answer 2 · answered Oct 10 '14 at 12:01

0

There is an overloaded constructor that takes an actual connection string.

This should do the trick:

public CustomContext()
                : base(CloudConfigurationManager.GetSetting("dbActivity"))
{
    // stuff here
}

Of course, the setting contains the (full) connection string.

answered Oct 10 '14 at 12:01

Brendan Green

11,676
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1

I tried this solution before, but I still get the same exception. It looks like it is only accepting the connection string name, not the connection string itself – Bonomi Oct 10 '14 at 13:32
What is the exception that is thrown? What version of EF are you using? What does the configuration in your `ServiceConfiguration.Local.cscfg` look like? I am doing the above and it is working fine with EF 6. – Brendan Green Oct 10 '14 at 13:41
WebRole or WorkerRole? Version of EF? – Brendan Green Oct 11 '14 at 03:28
I am using EF6 and WorkerRole – Bonomi Oct 11 '14 at 17:25

score 0 · Answer 3 · answered Oct 10 '14 at 12:01

0

I don't know it you can directly load it from a different config but there is a constructor for dbcontext that takes a connection string as input.

string connectionString = LoadFromConfig();
var context = new CustomContext(connectionString );

answered Oct 10 '14 at 12:01

David Turvey

2,891
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score 0 · Answer 4 · edited May 23 '17 at 12:08

I needed to do this, but wasn't able to change the actual DbContext constructor as it was in a shared library that was also used by projects that used an app.config. I ended out coming up with an alternative solution which was to programatically modify the app.config connection string inside the worker role itself.

See this for a way to do that: Change connection string & reload app.config at run time

The code I used was

string databaseConnectionString = CloudConfigurationManager.GetSetting("dbActivity");
Configuration config = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None);
ConnectionStringsSection connectionStringsSection = (ConnectionStringsSection) config.GetSection("connectionStrings");
connectionStringsSection.ConnectionStrings["dbActivity"].ConnectionString = databaseConnectionString;
config.Save();
ConfigurationManager.RefreshSection("connectionStrings");

For this to work you need to have an empty connection string inside the app.config for which it will overwrite

<connectionStrings>
    <add name="dbActivity" connectionString="" providerName="System.Data.SqlClient" />
</connectionStrings>

Customize DbContext using connection string from ServiceConfiguration (Azure)

4 Answers4