Migration.cs supports single-file migration history format

Scans for migration resources in either old-style "scattered" (one file per version)
or new-style "integrated" format (single file "Resources/{StoreName}.migrations[.nnn]") with ":VERSION nnn" sections).
In the new-style migrations it also recognizes ':GO' separators for parts of the SQL script
that must be sent to the server separately.  The old-style migrations are loaded each in one piece
and don't support the ':GO' feature.

Status:  TESTED and works fine in all modes!
soprefactor
AlexRa 2010-05-16 16:22:38 +03:00
parent 3e1f2ddb8e
commit f4450ccf4f
1 changed files with 238 additions and 109 deletions

View File

@ -70,61 +70,111 @@ namespace OpenSim.Data
public class Migration
{
private static readonly ILog m_log = LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType);
protected static readonly ILog m_log = LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType);
private string _type;
private DbConnection _conn;
// private string _subtype;
private Assembly _assem;
private Regex _match;
protected string _type;
protected DbConnection _conn;
protected Assembly _assem;
private static readonly string _migrations_create = "create table migrations(name varchar(100), version int)";
// private static readonly string _migrations_init = "insert into migrations values('migrations', 1)";
// private static readonly string _migrations_find = "select version from migrations where name='migrations'";
private Regex _match_old;
private Regex _match_new;
public Migration(DbConnection conn, Assembly assem, string type)
/// <summary>Have the parameterless constructor just so we can specify it as a generic parameter with the new() constraint.
/// Currently this is only used in the tests. A Migration instance created this way must be then
/// initialized with Initialize(). Regular creation should be through the parameterized constructors.
/// </summary>
public Migration()
{
_type = type;
_conn = conn;
_assem = assem;
_match = new Regex(@"\.(\d\d\d)_" + _type + @"\.sql");
Initialize();
}
public Migration(DbConnection conn, Assembly assem, string subtype, string type)
{
Initialize(conn, assem, type, subtype);
}
public Migration(DbConnection conn, Assembly assem, string type)
{
Initialize(conn, assem, type, "");
}
/// <summary>Must be called after creating with the parameterless constructor.
/// NOTE that the Migration class now doesn't access database in any way during initialization.
/// Specifically, it won't check if the [migrations] table exists. Such checks are done later:
/// automatically on Update(), or you can explicitly call InitMigrationsTable().
/// </summary>
/// <param name="conn"></param>
/// <param name="assem"></param>
/// <param name="subtype"></param>
/// <param name="type"></param>
public void Initialize (DbConnection conn, Assembly assem, string type, string subtype)
{
_type = type;
_conn = conn;
_assem = assem;
_match = new Regex(subtype + @"\.(\d\d\d)_" + _type + @"\.sql");
Initialize();
_match_old = new Regex(subtype + @"\.(\d\d\d)_" + _type + @"\.sql");
string s = String.IsNullOrEmpty(subtype) ? _type : _type + @"\." + subtype;
_match_new = new Regex(@"\." + s + @"\.migrations(?:\.(?<ver>\d+)$|.*)");
}
private void Initialize()
public void InitMigrationsTable()
{
// clever, eh, we figure out which migrations version we are
int migration_version = FindVersion(_conn, "migrations");
if (migration_version > 0)
return;
// If not, create the migration tables
using (DbCommand cmd = _conn.CreateCommand())
// NOTE: normally when the [migrations] table is created, the version record for 'migrations' is
// added immediately. However, if for some reason the table is there but empty, we want to handle that as well.
int ver = FindVersion(_conn, "migrations");
if (ver <= 0) // -1 = no table, 0 = no version record
{
cmd.CommandText = _migrations_create;
cmd.ExecuteNonQuery();
}
if( ver < 0 )
ExecuteScript("create table migrations(name varchar(100), version int)");
InsertVersion("migrations", 1);
}
}
/// <summary>Executes a script, possibly in a database-specific way.
/// It can be redefined for a specific DBMS, if necessary. Specifically,
/// to avoid problems with proc definitions in MySQL, we must use
/// MySqlScript class instead of just DbCommand. We don't want to bring
/// MySQL references here, so instead define a MySQLMigration class
/// in OpenSim.Data.MySQL
/// </summary>
/// <param name="conn"></param>
/// <param name="script">Array of strings, one-per-batch (often just one)</param>
protected virtual void ExecuteScript(DbConnection conn, string[] script)
{
using (DbCommand cmd = conn.CreateCommand())
{
cmd.CommandTimeout = 0;
foreach (string sql in script)
{
cmd.CommandText = sql;
cmd.ExecuteNonQuery();
}
}
}
protected void ExecuteScript(DbConnection conn, string sql)
{
ExecuteScript(conn, new string[]{sql});
}
protected void ExecuteScript(string sql)
{
ExecuteScript(_conn, sql);
}
protected void ExecuteScript(string[] script)
{
ExecuteScript(_conn, script);
}
public void Update()
{
int version = 0;
version = FindVersion(_conn, _type);
InitMigrationsTable();
SortedList<int, string> migrations = GetMigrationsAfter(version);
int version = FindVersion(_conn, _type);
SortedList<int, string[]> migrations = GetMigrationsAfter(version);
if (migrations.Count < 1)
return;
@ -132,24 +182,27 @@ namespace OpenSim.Data
m_log.InfoFormat("[MIGRATIONS] Upgrading {0} to latest revision {1}.", _type, migrations.Keys[migrations.Count - 1]);
m_log.Info("[MIGRATIONS] NOTE: this may take a while, don't interupt this process!");
using (DbCommand cmd = _conn.CreateCommand())
{
foreach (KeyValuePair<int, string> kvp in migrations)
foreach (KeyValuePair<int, string[]> kvp in migrations)
{
int newversion = kvp.Key;
cmd.CommandText = kvp.Value;
// we need to up the command timeout to infinite as we might be doing long migrations.
cmd.CommandTimeout = 0;
/* [AlexRa 01-May-10]: We can't always just run any SQL in a single batch (= ExecuteNonQuery()). Things like
* stored proc definitions might have to be sent to the server each in a separate batch.
* This is certainly so for MS SQL; not sure how the MySQL connector sorts out the mess
* with 'delimiter @@'/'delimiter ;' around procs. So each "script" this code executes now is not
* a single string, but an array of strings, executed separately.
*/
try
{
cmd.ExecuteNonQuery();
ExecuteScript(kvp.Value);
}
catch (Exception e)
{
m_log.DebugFormat("[MIGRATIONS] Cmd was {0}", cmd.CommandText);
m_log.DebugFormat("[MIGRATIONS]: An error has occurred in the migration {0}.\n This may mean you could see errors trying to run OpenSim. If you see database related errors, you will need to fix the issue manually. Continuing.", e.Message);
cmd.CommandText = "ROLLBACK;";
cmd.ExecuteNonQuery();
m_log.DebugFormat("[MIGRATIONS] Cmd was {0}", kvp.Value.ToString());
m_log.DebugFormat("[MIGRATIONS]: An error has occurred in the migration {0}.\n This may mean you could see errors trying to run OpenSim. If you see database related errors, you will need to fix the issue manually. Migration aborted.", e.Message);
ExecuteScript("ROLLBACK;");
return;
}
if (version == 0)
@ -163,25 +216,6 @@ namespace OpenSim.Data
version = newversion;
}
}
}
// private int MaxVersion()
// {
// int max = 0;
// string[] names = _assem.GetManifestResourceNames();
// foreach (string s in names)
// {
// Match m = _match.Match(s);
// if (m.Success)
// {
// int MigrationVersion = int.Parse(m.Groups[1].ToString());
// if (MigrationVersion > max)
// max = MigrationVersion;
// }
// }
// return max;
// }
public int Version
{
@ -206,7 +240,7 @@ namespace OpenSim.Data
try
{
cmd.CommandText = "select version from migrations where name='" + type + "' order by version desc";
using (IDataReader reader = cmd.ExecuteReader())
using (DbDataReader reader = cmd.ExecuteReader())
{
if (reader.Read())
{
@ -217,7 +251,8 @@ namespace OpenSim.Data
}
catch
{
// Something went wrong, so we're version 0
// Something went wrong (probably no table), so we're at version -1
version = -1;
}
}
return version;
@ -225,57 +260,151 @@ namespace OpenSim.Data
private void InsertVersion(string type, int version)
{
using (DbCommand cmd = _conn.CreateCommand())
{
cmd.CommandText = "insert into migrations(name, version) values('" + type + "', " + version + ")";
m_log.InfoFormat("[MIGRATIONS]: Creating {0} at version {1}", type, version);
cmd.ExecuteNonQuery();
}
ExecuteScript("insert into migrations(name, version) values('" + type + "', " + version + ")");
}
private void UpdateVersion(string type, int version)
{
using (DbCommand cmd = _conn.CreateCommand())
{
cmd.CommandText = "update migrations set version=" + version + " where name='" + type + "'";
m_log.InfoFormat("[MIGRATIONS]: Updating {0} to version {1}", type, version);
cmd.ExecuteNonQuery();
}
ExecuteScript("update migrations set version=" + version + " where name='" + type + "'");
}
// private SortedList<int, string> GetAllMigrations()
// {
// return GetMigrationsAfter(0);
// }
private delegate void FlushProc();
private SortedList<int, string> GetMigrationsAfter(int after)
/// <summary>Scans for migration resources in either old-style "scattered" (one file per version)
/// or new-style "integrated" format (single file with ":VERSION nnn" sections).
/// In the new-style migrations it also recognizes ':GO' separators for parts of the SQL script
/// that must be sent to the server separately. The old-style migrations are loaded each in one piece
/// and don't support the ':GO' feature.
/// </summary>
/// <param name="after">The version we are currently at. Scan for any higher versions</param>
/// <returns>A list of string arrays, representing the scripts.</returns>
private SortedList<int, string[]> GetMigrationsAfter(int after)
{
string[] names = _assem.GetManifestResourceNames();
SortedList<int, string> migrations = new SortedList<int, string>();
// because life is funny if we don't
Array.Sort(names);
SortedList<int, string[]> migrations = new SortedList<int, string[]>();
string[] names = _assem.GetManifestResourceNames();
if( names.Length == 0 ) // should never happen
return migrations;
Array.Sort(names); // we want all the migrations ordered
int nLastVerFound = 0;
Match m = null;
string sFile = Array.FindLast(names, nm => { m = _match_new.Match(nm); return m.Success; }); // ; nm.StartsWith(sPrefix, StringComparison.InvariantCultureIgnoreCase
if( (m != null) && !String.IsNullOrEmpty(sFile) )
{
/* The filename should be '<StoreName>.migrations[.NNN]' where NNN
* is the last version number defined in the file. If the '.NNN' part is recognized, the code can skip
* the file without looking inside if we have a higher version already. Without the suffix we read
* the file anyway and use the version numbers inside. Any unrecognized suffix (such as '.sql')
* is valid but ignored.
*
* NOTE that we expect only one 'merged' migration file. If there are several, we take the last one.
* If you are numbering them, leave only the latest one in the project or at least make sure they numbered
* to come up in the correct order (e.g. 'SomeStore.migrations.001' rather than 'SomeStore.migrations.1')
*/
if (m.Groups.Count > 1 && int.TryParse(m.Groups[1].Value, out nLastVerFound))
{
if( nLastVerFound <= after )
goto scan_old_style;
}
System.Text.StringBuilder sb = new System.Text.StringBuilder(4096);
int nVersion = -1;
List<string> script = new List<string>();
FlushProc flush = delegate()
{
if (sb.Length > 0) // last SQL stmt to script list
{
script.Add(sb.ToString());
sb.Length = 0;
}
if ( (nVersion > 0) && (nVersion > after) && (script.Count > 0) && !migrations.ContainsKey(nVersion)) // script to the versioned script list
{
migrations[nVersion] = script.ToArray();
}
script.Clear();
};
using (Stream resource = _assem.GetManifestResourceStream(sFile))
using (StreamReader resourceReader = new StreamReader(resource))
{
int nLineNo = 0;
while (!resourceReader.EndOfStream)
{
string sLine = resourceReader.ReadLine();
nLineNo++;
if( String.IsNullOrEmpty(sLine) || sLine.StartsWith("#") ) // ignore a comment or empty line
continue;
if (sLine.Trim().Equals(":GO", StringComparison.InvariantCultureIgnoreCase))
{
if (sb.Length == 0) continue;
if (nVersion > after)
script.Add(sb.ToString());
sb.Length = 0;
continue;
}
if (sLine.StartsWith(":VERSION ", StringComparison.InvariantCultureIgnoreCase)) // ":VERSION nnn"
{
flush();
int n = sLine.IndexOf('#'); // Comment is allowed in version sections, ignored
if (n >= 0)
sLine = sLine.Substring(0, n);
if (!int.TryParse(sLine.Substring(9).Trim(), out nVersion))
{
m_log.ErrorFormat("[MIGRATIONS]: invalid version marker at {0}: line {1}. Migration failed!", sFile, nLineNo);
break;
}
}
else
{
sb.AppendLine(sLine);
}
}
flush();
// If there are scattered migration files as well, only look for those with higher version numbers.
if (after < nVersion)
after = nVersion;
}
}
scan_old_style:
// scan "old style" migration pieces anyway, ignore any versions already filled from the single file
foreach (string s in names)
{
Match m = _match.Match(s);
m = _match_old.Match(s);
if (m.Success)
{
int version = int.Parse(m.Groups[1].ToString());
if (version > after)
if ( (version > after) && !migrations.ContainsKey(version) )
{
using (Stream resource = _assem.GetManifestResourceStream(s))
{
using (StreamReader resourceReader = new StreamReader(resource))
{
string resourceString = resourceReader.ReadToEnd();
migrations.Add(version, resourceString);
string sql = resourceReader.ReadToEnd();
migrations.Add(version, new string[]{sql});
}
}
}
}
}
if (migrations.Count < 1) {
if (migrations.Count < 1)
{
m_log.InfoFormat("[MIGRATIONS]: {0} up to date, no migrations to apply", _type);
}
return migrations;