Migration scripts not found when using Azure App Service

[ld0614]

Configuration:
C# .Net 4.6.2
Azure SQL Server V12
Azure App Service

Migration Launcher:

try
{
	string connectionString = Settings.GetSettings().DatabaseConnectionString;
	SqlConnection cnx = new SqlConnection(connectionString);
	Evolve.Evolve evolve = new Evolve.Evolve(cnx, msg => Trace.TraceInformation(msg))
	{
		Driver = "SqlClient", //Connect to SQL Server
		Locations = new List<string> { "db/migrations" },
		IsEraseDisabled = true, //Do not allow Erasing of schema
		EnableClusterMode = true //Ensure that no other instances also attempt to migrate the database as the same time
	};

	evolve.Migrate();
}
catch (Exception ex)
{
	Trace.TraceError("Database migration failed.", ex);
	throw;
}
}

SQL files have been written and are uploaded to the web server:

During start the following logs are provided

Application: 2018-08-30T14:46:57  PID[5928] Information Executing Migrate...
Application: 2018-08-30T14:46:57  PID[5928] Information Evolve initialized.
Application: 2018-08-30T14:46:57  PID[5928] Information No metadata found.
Application: 2018-08-30T14:46:57  PID[5928] Information Database is up to date. No migration needed.

And a single blank changelog table has been created:

As far as I can tell I've followed all the requirements for using Evolve but I'm unsure of how to troubleshoot this issue further, any assistance would be greatly appreciated.

[lecaillon]

Hi @ld0614

Since the changelog table has been created, it means that Evolve is able to connect to your database.
Your migration scripts seem to be well named.
So I think it does not find any of your sql migration files.
Have you set the property Copy to output directory to Copy always on each of your sql file ?

I realize the doc might not be specific about this point when you use the In-app mode ... ?

[ld0614]

Hi @lecaillon, thanks for getting back so soon, the screenshot above is a view of the web server file structure showing the files on the web server. The below screenshot if the file configuration.

The only thing I really stray from your example is in the code launch, in Global.asax.cs I have the following line:

UpdateDatabase.UpdateDatabaseUsingEvolve();

This then calls the updateDatabase class which is saved in App_Start\UpdateDatabase.cs file. The db\migration path is at the root of the directory.

I have also attempted to place the files at /bin/App_Start/db/migrations as the dlls for the website are at /bin. After updating the file locations to either bin/App_Start/db/migrations or Add_Start/db/migrations nither returned a different log message.

[lecaillon]

ok, in fact Evolve searches migration files in the current app directory combine with the value of the Locations parameter. Or in the Locations parameter only if you have define a full path.
So in our case I see the db folder is next the bin folder.
Thus I would try:

Locations = new List { "../db/migrations" },

[ld0614]

Thanks for all your assistance, after a few experiments I discovered that the working directory on an Azure App Service is fixed to D:\Windows\System32. thus all uses of DirectoryInfo where branching off of there. using ../db/migrations" didn't help either as this returned to the root of the D drive. To fix I added the following code:

string currentPath = System.Web.HttpContext.Current.Server.MapPath("~");
Locations = new List<string> { currentPath + "db\\migrations" },

This maps to the correct root folder which can then be changed to the correct relative folder.

To assist with future debugging may I suggest a branch from here:

Evolve/src/Evolve/Migration/FileMigrationLoader.cs

Line 29 in 25dab78

if(!dirToScan.Exists) continue;

which would write a message if it was unable to locate the directory (ideally with the offending path)?

[lecaillon]

Nice, i did not know.
I will think about a way of logging locations that do not exist.

Can I change your title issue to something like: "Scripts not found in Azure App Service" ?