/// <summary>
/// Generates C# Migrations that Create tables Migrations
/// </summary>
/// <param name="context">The context that define how parts of the C# will be formatted</param>
/// <param name="schemaDumper">The schema dump to use as the source of the schema migration</param>
public void GenerateMigrations(SchemaMigrationContext context, ISchemaDumper schemaDumper)
{
_announcer.Say("Reading database schema");
var defs = schemaDumper.ReadDbSchema();
if (context.PreMigrationTableUpdate != null)
context.PreMigrationTableUpdate(defs);
SetupMigrationsDirectory(context);
var migrations = 0;
var foreignkeyTables = new List<TableDefinition>();
foreach (var table in defs)
{
// Check if we want to exclude this table
if ( context.ExcludeTables.Contains(table.Name))
{
_announcer.Say("Exluding table " + table.Name);
continue;
}
if (context.MigrationRequired(MigrationType.Tables) || (context.MigrationRequired(MigrationType.Indexes) && table.Indexes.Count > 0))
{
migrations++;
var migrationsFolder = Path.Combine(context.WorkingDirectory, context.MigrationsDirectory);
var csFilename = Path.Combine(migrationsFolder, context.MigrationClassNamer(context.MigrationIndex + migrations, table) + ".cs");
_announcer.Say("Creating migration " + Path.GetFileName(csFilename));
using (var writer = new StreamWriter(csFilename))
{
WriteToStream(context, table, context.MigrationIndex + migrations, writer);
}
}
if (context.MigrationRequired(MigrationType.Data))
{
var data = schemaDumper.ReadTableData(table.SchemaName, table.Name);
if (data != null && data.Tables.Count > 0 && data.Tables[0].Rows.Count > 0)
{
var dataDirectory = Path.Combine(context.WorkingDirectory, context.DataDirectory);
if (!Directory.Exists(dataDirectory))
Directory.CreateDirectory(dataDirectory);
data.Tables[0].WriteXmlSchema(Path.Combine(dataDirectory, table.Name + ".xsd"));
using (var writer = new XmlTextWriter(Path.Combine(dataDirectory, table.Name + ".xml"), context.MigrationEncoding))
{
data.Tables[0].WriteXml(writer);
}
}
}
if (context.MigrationRequired(MigrationType.ForeignKeys) && table.ForeignKeys.Count > 0)
{
// Add to list of tables to apply foreign key
// ... done as two part process as may me interdepdancies between tables
foreignkeyTables.Add(table);
}
}
context.MigrationIndex += migrations;
if (context.MigrationRequired(MigrationType.ForeignKeys))
GenerateForeignKeyMigrations(context, foreignkeyTables);
}
/// <summary>
/// Writes the Migration Up() and Down()
/// </summary>
/// <param name="context">The context that controls how the column should be generated</param>
/// <param name="table">the table to generate the migration for</param>
/// <param name="migration">The migration index to apply</param>
/// <param name="output">The output stream to append the C# code to</param>
private void WriteToStream(SchemaMigrationContext context, TableDefinition table, int migration, StreamWriter output)
{
WriteMigration(output, context, migration
, () => context.MigrationClassNamer(migration, table)
,() => WriteTable(context, table, output)
, () => WriteDeleteTable(context, table, output));
}
private void GenerateForeignKeyMigrations(SchemaMigrationContext context, List<TableDefinition> tables)
{
if (!context.MigrationRequired(MigrationType.ForeignKeys) || tables.Count <= 0)
{
return;
}
_announcer.Say(string.Format("Found {0} tables with foreign keys", tables.Count));
var migrations = 0;
foreach (var foreignkeyTable in tables)
{
var migrationsFolder = Path.Combine(context.WorkingDirectory, context.MigrationsDirectory);
migrations++;
var migrationIndex = context.MigrationIndex+ migrations;
var table = foreignkeyTable;
var csFilename = Path.Combine(migrationsFolder,
context.MigrationClassNamer(migrationIndex, table) + "ForeignKey.cs");
_announcer.Say("Creating migration " + Path.GetFileName(csFilename));
using (var writer = new StreamWriter(csFilename))
{
WriteMigration(writer, context, migrationIndex
, () => context.MigrationClassNamer(migrationIndex, table) + "ForeignKey"
, () => WriteForeignKey(table, writer)
, () => WriteDeleteForeignKey(table, writer));
}
}
context.MigrationIndex += migrations;
}