// write given buffer to db
// displays form to user to please wait
// could make use of BackgroundWorker to prevent lockup, or async
public void Write(WatcherEventBuffer buffer)
{
// get lock on db
lock (lockObj) {
// ensure the connection is alive first
if (!AliveCheck())
{
return;
}
// get buffer as new queue (to avoid having to keep is locked during DB write)
Queue <WatcherEventArgs> queue = buffer.DequeueToQueue();
// form to display to user while writing to db
FormWriteWait waitForm = new FormWriteWait();
waitForm.Show();
waitForm.Refresh();
try {
// create command obj
SQLiteCommand com = sqlite_connection.CreateCommand();
while (queue.Count > 0)
{
// dequque
WatcherEventArgs args = queue.Dequeue();
// generate insert and execute
com.CommandText = GenerateInsert(args);
com.ExecuteNonQuery();
}
} catch (Exception e) {
// check if is an SQLite exception
// just to avoid having to do 2 of almost the same catch blocks
if (e is SQLiteException)
{
System.Windows.Forms.MessageBox.Show(string.Format("Failed to write to database\nSQLite Exception: {0}", e.Message));
}
else
{
System.Windows.Forms.MessageBox.Show(string.Format("Failed to write to database\nException: {0}", e.Message));
}
}
// close form
waitForm.Close();
// pass remaining queue back to buffer (if there was an error)
while (queue.Count > 0)
{
buffer.Enqueue(queue.Dequeue());
}
}
}
// methods
// log method, compiles event message, reports to screen/log file
// string fullPath, absolute path to item changed
// string change, change that occurred
private static void Event(string fullPath, string change)
{
// determine if item was file or directory for message
// cannot use DirectoryInfo/FileInfo because if created file is changed/renames right after they will not function properly
// various other edge cases like that
// also does not work with deletes
string itemType = "unknown";
string itemName = fullPath;
// tokenize by '\'
string[] toks = fullPath.Split('\\');
// grab last token as itemName
itemName = toks[toks.Length - 1];
// treat as, if contains '.' then is a file - else directory
if (itemName.Contains("."))
{
// get extension name
toks = itemName.Split('.');
itemType = toks[toks.Length - 1];
}
else
{
itemType = "Directory";
}
// ignore updates on "unknown" or "directory" types
if (itemType == "unknown" || itemType == "Directory")
{
return;
}
// check if item type is filtered
if (filters.Filtered(itemType))
{
return;
}
// Build arguments for event
WatcherEventArgs args = new WatcherEventArgs(itemType, itemName, fullPath, change, DateTime.Now);
// Invoke event for Form
// ? to check for null, in case of race conditions
// but shouldn't happen as long as Monitor sets up the event fnc before path and watching variable
watcherEvent?.Invoke(args);
}
// generates Insert statement for args
private string GenerateInsert(WatcherEventArgs args)
{
// convert DateTime from args to unix time (in seconds)
DateTimeOffset offset = args.EventDateTime;
long unixTimeStamp = offset.ToUnixTimeSeconds();
// doesn't save UTC offset of machine, so on db query conversion will use current UTC machine to convert
// generate and return insert
return(string.Format("INSERT INTO '{0}' {1} VALUES ('{2}','{3}','{4}','{5}',{6});",
currentTableName,
TableSchema(),
args.ItemName,
args.ItemType,
args.Path,
args.EventName,
unixTimeStamp));
}
// Watcher event
public void EH_MonitorEvent(WatcherEventArgs args)
{
if (DataGridViewEvents.InvokeRequired)
{
// Need to invoke so is on main thread
WatcherEventHandler handler = EH_MonitorEvent;
Invoke(handler, args);
}
else
{
// add to data grid
DataGridViewEvents.Rows.Add(args.ItemName, args.ItemType, args.Path, args.EventName, args.EventDateTime);
// only push to buffer if db is active
if (eventDB.Active)
{
// push to buffer
eventBuffer.Enqueue(args);
}
}
}
// query for list of extensions
public List <WatcherEventArgs> QueryFor(List <string> extList)
{
// get lock on db
lock (lockObj) {
List <WatcherEventArgs> queryResults = new List <WatcherEventArgs>();
// ensure the connection is alive first
if (!AliveCheck())
{
return(queryResults);
}
// sqlite command obj
SQLiteCommand com = null;
// sqlite reader obj
SQLiteDataReader reader = null;
try {
// create command
com = sqlite_connection.CreateCommand();
// build query
com.CommandText = GenerateQuery(extList);
// create data reader
reader = com.ExecuteReader();
// loop through reader
while (reader.Read())
{
// retrieve info, build new args, add to list
WatcherEventArgs parsed = ParseRead(reader);
if (parsed != null)
{
queryResults.Add(parsed);
}
}
} catch (Exception e) {
// check if is an SQLite exception
// just to avoid having to do 2 of almost the same catch blocks
if (e is SQLiteException)
{
System.Windows.Forms.MessageBox.Show(string.Format("Failed to query database\nSQLite Exception: {0}", e.Message));
}
else
{
System.Windows.Forms.MessageBox.Show(string.Format("Failed to query database\nException: {0}", e.Message));
}
} finally {
// cleanup
if (com != null)
{
if (reader != null)
{
reader.Dispose();
}
com.Dispose();
}
}
return(queryResults);
}
}
// Enqueue
public void Enqueue(WatcherEventArgs watcherEvent)
{
lock (lockObj) {
buffer.Enqueue(watcherEvent);
}
}
