EF 4.3 migrations throwing “Unable to open configSource file”

Question

I'm trying to use EF 4.3 migrations feature. My ASP.NET MVC project stores connection strings in external file:

<connectionStrings configSource="bin\connections.config" />

All runtime procedures (including automatic migrations) work fine. However, no powershell commandlet, connecting to the database, is able to find external file. It throws "Unable to open configSource file" exception. I was trying to place .config file in different places as well as changing configured external file location to no avail. Is there any workaround available?

Update: I've found that EF creates a temporary AppDomain with configuration file located in temp directory. So the only workaround at the moment, it seems, is to place external configuration in the same temp directory. Any other suggestions?

Answer 1

There are unfortunately no easy way to handle external configSource files with the powershell cmd-lets in EF migrations. I've given up on it and moved the connection strings into the config file for the class library that contains the db code. The alternative is, as you've found out yourself to manually copy the file. Unfortunately the copy process doesn't honor the build settings of the project, so setting the external config file to be copied at build doesn't help.

EF 4.3.1 supports configSource.

Answer 2

Using EF 6.1 here.

If like me you were linking to a connectionStrings.config file located in another project than your Entity Framework migrations project (using Add as link), you'll probably need to move the file back to this EF project and link to the moved file from the other projects instead...