Use UCanAccess with IKVM with C# from an Azure Function

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 I need to read an MS-Access file from an Azure Function and Access Database Engine does not work in this scenario. I've found UCanAccess library, and I tried all the suggestions from UCanAccess, IKVM and C#, and my current code looks like this:

internal string QueryData(string tableName)
        {
            Properties props = new Properties();
            props.setProperty("user.language", "en");
            props.setProperty("user.country", "US");
            props.setProperty("locale", "en_US");
            props.setProperty("hsqldb.reconfig_logging", "false");
            string connString = "jdbc:ucanaccess://D:\\path to\\mdb file\\myfile.mdb";
            ikvm.runtime.Startup.addBootClassPathAssembly(System.Reflection.Assembly.Load("ucanaccess-5.0.1"));
            java.sql.Driver v_driver = (java.sql.Driver)java.lang.Class.forName("net.ucanaccess.jdbc.UcanaccessDriver, ucanaccess-5.0.1, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null").newInstance();
            java.sql.Connection v_con = v_driver.connect(connString, props);
            v_con.setReadOnly(true);
            v_con.clearWarnings();
            java.sql.Statement v_st = v_con.createStatement();
            java.sql.ResultSet v_res = v_st.executeQuery(string.Format("select top 10 * from {0}", tableName));
            java.sql.ResultSetMetaData v_resmd = v_res.getMetaData();
            StringBuilder stringBuilder = new();
            for (int i = 1; i <= v_resmd.getColumnCount(); i++)
                stringBuilder.AppendLine(v_resmd.getColumnLabel(i) + "|");

            while (v_res.next())
            {
                for (int i = 1; i <= v_resmd.getColumnCount(); i++)
                    stringBuilder.AppendLine(v_res.getString(i) + "|");
            }
            return stringBuilder.ToString();

}

The code above is in a separate class called from the function method which is invoked with a "get" operation. If I try the code in a console program, it works, but if I try to use the same code in the azure function, I'm getting the following error:

System.Private.CoreLib: Exception while executing function: myFunctionName. ucanaccess-5.0.1: java.util.MissingResourceException: Can't find bundle for base name net.ucanaccess.util.logger_messages, locale es_CO

As the message seemed to be related to locale configuration, I tried to change locale and languague properties through an instance of Properties class as shown above and using it as a parameter to instance the driver with no luck. Also, all the properties set were for trial/error tests.

As for why I'm trying to do this in an Azure Function, the reason is I have several mdb files in a shared folder, accesible through a VPN. the VPN is configured in Azure with a VNet and is accesible from the Function, and the goal is to read the files, transform the data and return it in json format. The function will be called from a Logic App.

The error message you received indicates that the UCanAccess library is unable to find the resource bundle for the specified locale. This error can occur when the library is not able to locate the required files or dependencies.

To troubleshoot this issue, you can try the following:

  1. Check if all the required dependencies are included in your project. You can try copying the required files to the bin folder of your Azure Function.

  2. Make sure that the IKVM library is properly configured in your Azure Function. You can try loading the required assemblies explicitly using the Assembly.LoadFrom method.

  3. Verify that the mdb file is accessible from the Azure Function. You can try accessing the file from the Function using the File.Exists method.

  4. Check if the UCanAccess library requires any specific permissions or configurations to work in an Azure Function. You can try running the Azure Function in an elevated environment to see if it resolves the issue.

  5. Try changing the locale and language properties to a valid value for your system. You can try using the "en_US" locale and "en" language for testing purposes.

If none of these solutions work, you can try using an alternative library or approach to access the mdb file in your Azure Function. For example, you can try using the OleDB provider to access the mdb file or consider migrating the data to a different format that is better supported by Azure Functions.



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