add reset function to db backend

backend/db/sql-generic.c

@@ -2145,4 +2145,157 @@ backend_iterate(gpointer _iterator, bson_t* metadata, GError** error)
 	/*something failed very hard*/
 	return FALSE;
 }
+
+static
+gboolean
+backend_reset(gpointer _batch, GError** error)
+{
+	J_TRACE_FUNCTION(NULL);
+
+	JDBType type;
+	JThreadVariables* thread_variables = NULL;
+	void* stmt1;
+	void* stmt2;
+	JSqlBatch* batch = _batch;
+	gboolean found1 = FALSE;
+	gboolean found2 = FALSE;
+	g_autoptr(GArray) arr_types_out1 = NULL;
+	g_autoptr(GArray) arr_types_out2 = NULL;
+	JDBTypeValue value1;
+	JDBTypeValue value2;
+	char sql_strbuf[256];
+	char table_name[128];
+	g_autoptr(GString) error_string = NULL;
+
+	g_return_val_if_fail(_batch != NULL, FALSE);
+	g_return_val_if_fail(error == NULL || *error == NULL, FALSE);
+
+	if (G_UNLIKELY(!(thread_variables = thread_variables_get(error))))
+	{
+		goto _error3;
+	}
+	if (G_UNLIKELY(!_backend_batch_execute(batch, error)))
+	{
+		//no ddl in transaction - most databases wont support that - continue without any open transaction
+		goto _error3;
+	}
+	arr_types_out1 = g_array_new(FALSE, FALSE, sizeof(JDBType));
+	type = J_DB_TYPE_STRING;
+	g_array_append_val(arr_types_out1, type);
+	arr_types_out2 = g_array_new(FALSE, FALSE, sizeof(JDBType));
+	type = J_DB_TYPE_UINT32;
+	g_array_append_val(arr_types_out2, type);
+	do
+	{
+		snprintf(sql_strbuf, sizeof(sql_strbuf), sql_get_table_names, batch->namespace);
+		if (G_UNLIKELY(!j_sql_prepare(thread_variables->sql_backend, sql_strbuf, &stmt1, NULL, arr_types_out1, error)))
+		{
+			goto _error3;
+		}
+		if (G_UNLIKELY(!j_sql_step(thread_variables->sql_backend, stmt1, &found1, error)))
+		{
+			goto _error2;
+		}
+		if (!found1)
+		{
+			break;
+		}
+		value1.val_string = NULL;
+		if (G_UNLIKELY(!j_sql_column(thread_variables->sql_backend, stmt1, 0, J_DB_TYPE_STRING, &value1, error)))
+		{
+			goto _error2;
+		}
+		strncpy(table_name, value1.val_string, sizeof(table_name));
+		if (G_UNLIKELY(!j_sql_reset(thread_variables->sql_backend, stmt1, error)))
+		{
+			goto _error2;
+		}
+		if (G_UNLIKELY(!j_sql_finalize(thread_variables->sql_backend, stmt1, error)))
+		{
+			goto _error3;
+		}
+		snprintf(sql_strbuf, sizeof(sql_strbuf), "SELECT COUNT(*) FROM '%s'", table_name);
+		if (G_UNLIKELY(!j_sql_prepare(thread_variables->sql_backend, sql_strbuf, &stmt2, NULL, arr_types_out2, error)))
+		{
+			goto _error3;
+		}
+		if (G_UNLIKELY(!j_sql_step(thread_variables->sql_backend, stmt2, &found2, error)))
+		{
+			goto _error;
+		}
+		if (!found2)
+		{
+			g_set_error(error, J_BACKEND_DB_ERROR, 0, "reset %s count not found", table_name);
+			goto _error;
+		}
+		if (G_UNLIKELY(!j_sql_column(thread_variables->sql_backend, stmt2, 0, J_DB_TYPE_UINT32, &value2, error)))
+		{
+			goto _error;
+		}
+		if (value2.val_uint32 > 0)
+		{
+			if (!error_string)
+				error_string = g_string_new("reset -- ");
+			g_string_append_printf(error_string, "%s -> %d, ", table_name, value2.val_uint32);
+		}
+		if (G_UNLIKELY(!j_sql_reset(thread_variables->sql_backend, stmt2, error)))
+		{
+			goto _error;
+		}
+		if (G_UNLIKELY(!j_sql_finalize(thread_variables->sql_backend, stmt2, error)))
+		{
+			goto _error3;
+		}
+		snprintf(sql_strbuf, sizeof(sql_strbuf), "DROP TABLE '%s'", table_name);
+		if (G_UNLIKELY(!j_sql_exec(thread_variables->sql_backend, sql_strbuf, error)))
+		{
+			goto _error3;
+		}
+	} while (TRUE);
+	if (G_UNLIKELY(!j_sql_reset(thread_variables->sql_backend, stmt1, error)))
+	{
+		goto _error2;
+	}
+	if (G_UNLIKELY(!j_sql_finalize(thread_variables->sql_backend, stmt1, error)))
+	{
+		goto _error3;
+	}
+	if (error_string)
+	{
+		g_set_error(error, J_BACKEND_DB_ERROR, 0, "%s", error_string->str);
+		goto _error3;
+	}
+	if (G_UNLIKELY(!_backend_batch_start(batch, error)))
+	{
+		goto _error3;
+	}
+	return TRUE;
+_error:
+	if (G_UNLIKELY(!j_sql_finalize(thread_variables->sql_backend, stmt2, NULL)))
+	{
+		goto _error2;
+	}
+	if (G_UNLIKELY(!_backend_batch_start(batch, NULL)))
+	{
+		goto _error;
+	}
+	return FALSE;
+_error2:
+	if (G_UNLIKELY(!j_sql_finalize(thread_variables->sql_backend, stmt1, NULL)))
+	{
+		goto _error3;
+	}
+	if (G_UNLIKELY(!_backend_batch_start(batch, NULL)))
+	{
+		goto _error;
+	}
+	return FALSE;
+_error3:
+	/*something failed very hard*/
+	if (G_UNLIKELY(!_backend_batch_start(batch, NULL)))
+	{
+		goto _error;
+	}
+	return FALSE;
+}
 #endif

backend/db/sqlite.c

@@ -40,6 +40,7 @@
 
 #define sql_autoincrement_string " "
 #define sql_last_insert_id_string " SELECT last_insert_rowid() "
+#define sql_get_table_names "SELECT name FROM sqlite_master WHERE type='table' AND name LIKE '%s_%%'"
 
 static gchar* path;
 
@@ -418,6 +419,7 @@ static
 JBackend sqlite_backend = {
 	.type = J_BACKEND_TYPE_DB,
 	.component = J_BACKEND_COMPONENT_SERVER,
+	.backend_reset = backend_reset,
 	.db = {
 		.backend_init = backend_init,
 		.backend_fini = backend_fini,

include/core/jbackend-operation.h

@@ -108,6 +108,8 @@ gboolean j_backend_operation_unwrap_db_update (JBackend*, gpointer, JBackendOper
 gboolean j_backend_operation_unwrap_db_delete (JBackend*, gpointer, JBackendOperation*);
 gboolean j_backend_operation_unwrap_db_query (JBackend*, gpointer, JBackendOperation*);
 
+gboolean j_backend_operation_unwrap_reset(JBackend* backend, gpointer, JBackendOperation*);
+
 gboolean j_backend_operation_to_message (JMessage* message, JBackendOperationParam* data, guint len);
 gboolean j_backend_operation_from_message (JMessage* message, JBackendOperationParam* data, guint len);
 gboolean j_backend_operation_from_message_static (JMessage* message, JBackendOperationParam* data, guint len);
@@ -241,6 +243,22 @@ static const JBackendOperation j_backend_operation_db_query = {
 	},
 };
 
+static const JBackendOperation j_backend_operation_reset = {
+	.backend_func = j_backend_operation_unwrap_reset,
+	.in_param_count = 1,
+	.out_param_count = 1,
+	.in_param = {
+		{
+			.type = J_BACKEND_OPERATION_PARAM_TYPE_STR,
+		},
+	},
+	.out_param = {
+		{
+			.type = J_BACKEND_OPERATION_PARAM_TYPE_ERROR,
+		},
+	},
+};
+
 G_END_DECLS
 
 #endif

include/core/jbackend.h

@@ -126,6 +126,13 @@ struct JBackend
 	JBackendType type;
 	JBackendComponent component;
 
+	/**
+	 * delete everything in the backend
+	 * \param[in] which namespace to delete
+	 * \param[out] how many "things" are deleted within the specified namespace
+	 */
+	gboolean (*backend_reset)(gpointer, GError**);
+
 	union
 	{
 		struct
@@ -431,6 +438,7 @@ gboolean j_backend_db_delete (JBackend*, gpointer, gchar const*, bson_t const*,
 gboolean j_backend_db_query (JBackend*, gpointer, gchar const*, bson_t const*, gpointer*, GError**);
 gboolean j_backend_db_iterate (JBackend*, gpointer, bson_t*, GError**);
 
+gboolean j_backend_reset (JBackend* backend, gpointer, GError**);
 G_END_DECLS
 
 #endif

include/core/jmessage.h

@@ -53,7 +53,8 @@ enum JMessageType
 	J_MESSAGE_DB_INSERT,
 	J_MESSAGE_DB_UPDATE,
 	J_MESSAGE_DB_DELETE,
-	J_MESSAGE_DB_QUERY
+	J_MESSAGE_DB_QUERY,
+	J_MESSAGE_RESET
 };
 
 typedef enum JMessageType JMessageType;

include/db/jdb-internal.h

@@ -114,6 +114,8 @@ gboolean j_db_internal_delete (gchar const* namespace, gchar const* name, bson_t
 gboolean j_db_internal_query (gchar const* namespace, gchar const* name, bson_t const* selector, gpointer* iterator, JBatch* batch, GError** error);
 gboolean j_db_internal_iterate (gpointer iterator, bson_t* metadata, GError** error);
 
+gboolean j_internal_reset (gchar const* namespace, JBatch* batch, GError** error);
+
 // Client-side additional internal functions
 bson_t* j_db_selector_get_bson (JDBSelector* selector);
 

lib/core/jbackend-operation.c

@@ -38,6 +38,15 @@
  * @{
  **/
 
+gboolean
+j_backend_operation_unwrap_reset(JBackend* backend, gpointer batch, JBackendOperation* data)
+{
+	J_TRACE_FUNCTION(NULL);
+
+	return j_backend_reset(backend, batch, data->out_param[0].ptr);
+}
+
+
 gboolean
 j_backend_operation_unwrap_db_schema_create (JBackend* backend, gpointer batch, JBackendOperation* data)
 {

lib/core/jbackend.c

@@ -897,6 +897,22 @@ j_backend_db_iterate (JBackend* backend, gpointer iterator, bson_t* metadata, GE
 	return ret;
 }
 
+gboolean
+j_backend_reset(JBackend* backend, gpointer batch, GError** error)
+{
+	J_TRACE_FUNCTION(NULL);
+
+	g_return_val_if_fail(backend != NULL, FALSE);
+	g_return_val_if_fail(batch != NULL, FALSE);
+	g_return_val_if_fail(error == NULL || *error == NULL, FALSE);
+
+	if (backend->backend_reset)
+	{
+		return backend->backend_reset(batch, error);
+	}
+	return TRUE;
+}
+
 /**
  * @}
  **/

lib/db/jdb-internal.c

@@ -153,6 +153,36 @@ j_backend_db_func_free (gpointer _data)
 	}
 }
 
+static
+gboolean
+j_reset_exec(JList* operations, JSemantics* semantics)
+{
+	J_TRACE_FUNCTION(NULL);
+
+	//FIXME call this on EVERY backend(type)
+	return j_backend_db_func_exec(operations, semantics, J_MESSAGE_RESET);
+}
+gboolean
+j_internal_reset(gchar const* namespace, JBatch* batch, GError** error)
+{
+	J_TRACE_FUNCTION(NULL);
+
+	JOperation* op;
+	JBackendOperation* data;
+
+	data = g_slice_new(JBackendOperation);
+	memcpy(data, &j_backend_operation_reset, sizeof(JBackendOperation));
+	data->in_param[0].ptr_const = namespace;
+	data->out_param[0].ptr_const = error;
+	op = j_operation_new();
+	op->key = namespace;
+	op->data = data;
+	op->exec_func = j_reset_exec;
+	op->free_func = j_backend_db_func_free;
+	j_batch_add(batch, op);
+	return TRUE;
+}
+
 static
 gboolean
 j_db_schema_create_exec (JList* operations, JSemantics* semantics)

server/loop.c

@@ -553,6 +553,13 @@ jd_handle_message (JMessage* message, GSocketConnection* connection, JMemoryChun
 				j_message_send(reply, connection);
 			}
 			break;
+	case J_MESSAGE_RESET:
+		if (!message_matched)
+		{
+			memcpy(&backend_operation, &j_backend_operation_reset, sizeof(JBackendOperation));
+			message_matched = TRUE;
+		}
+		// fallthrough
 		case J_MESSAGE_DB_SCHEMA_CREATE:
 			if (!message_matched)
 			{