storage/mozIStorageConnection.idl
author Chris H-C <chutten@mozilla.com>
Mon, 04 Jul 2016 11:16:05 -0400
changeset 312997 df28918fe2361f0b54ca9ce4773a29c4c0675d06
parent 303368 9b5be9da64bafc31baba3bc81c5d42785081e3d9
permissions -rw-r--r--
bug 1218576 - Support remote accumulation via JS histograms. r=gfritzsche The JS histograms, too, need to dispatch their accumulations from child to parent. JSHistograms_Add now only supports histograms that are in gHistogramsMap or that were created in the parent process. After bug 1288745, maybe we'll be able to change this to be less convoluted. MozReview-Commit-ID: 3qTH89YKbGP

/* -*- Mode: idl; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "nsISupports.idl"
#include "mozIStorageAsyncConnection.idl"

%{C++
namespace mozilla {
namespace dom {
namespace quota {
class QuotaObject;
}
}
}

%}

[ptr] native QuotaObject(mozilla::dom::quota::QuotaObject);

interface mozIStorageAggregateFunction;
interface mozIStorageCompletionCallback;
interface mozIStorageFunction;
interface mozIStorageProgressHandler;
interface mozIStorageBaseStatement;
interface mozIStorageStatement;
interface mozIStorageAsyncStatement;
interface mozIStorageStatementCallback;
interface mozIStoragePendingStatement;
interface nsIFile;

/**
 * mozIStorageConnection represents a database connection attached to
 * a specific file or to the in-memory data storage.  It is the
 * primary interface for interacting with a database, including
 * creating prepared statements, executing SQL, and examining database
 * errors.
 *
 * @note From the main thread, you should rather use mozIStorageAsyncConnection.
 *
 * @threadsafe
 */
[scriptable, uuid(4aa2ac47-8d24-4004-9b31-ec0bd85f0cc3)]
interface mozIStorageConnection : mozIStorageAsyncConnection {
  /**
   * Closes a database connection.  Callers must finalize all statements created
   * for this connection prior to calling this method.  It is illegal to use
   * call this method if any asynchronous statements have been executed on this
   * connection.
   *
   * @throws NS_ERROR_UNEXPECTED
   *         If any statement has been executed asynchronously on this object.
   * @throws NS_ERROR_UNEXPECTED
   *         If is called on a thread other than the one that opened it.
   */
  void close();

  /**
   * Clones a database connection and makes the clone read only if needed.
   * SQL Functions and attached on-disk databases are applied to the new clone.
   *
   * @param aReadOnly
   *        If true, the returned database should be put into read-only mode.
   *        Defaults to false.
   * @return the cloned database connection.
   *
   * @throws NS_ERROR_UNEXPECTED
   *         If this connection is a memory database.
   * @note If your connection is already read-only, you will get a read-only
   *       clone.
   * @note Due to a bug in SQLite, if you use the shared cache (openDatabase),
   *       you end up with the same privileges as the first connection opened
   *       regardless of what is specified in aReadOnly.
   * @note The following pragmas are copied over to a read-only clone:
   *        - cache_size
   *        - temp_store
   *       The following pragmas are copied over to a writeable clone:
   *        - cache_size
   *        - temp_store
   *        - foreign_keys
   *        - journal_size_limit
   *        - synchronous
   *        - wal_autocheckpoint
   *
   */
  mozIStorageConnection clone([optional] in boolean aReadOnly);

  /**
   * The default size for SQLite database pages used by mozStorage for new
   * databases.
   */
  readonly attribute long defaultPageSize;

  /**
   * Indicates if the connection is open and ready to use.  This will be false
   * if the connection failed to open, or it has been closed.
   */
  readonly attribute boolean connectionReady;

  /**
   * lastInsertRowID returns the row ID from the last INSERT
   * operation.
   */
  readonly attribute long long lastInsertRowID;

  /**
   * affectedRows returns the number of database rows that were changed or
   * inserted or deleted by last operation.
   */
  readonly attribute long affectedRows;

  /**
   * The last error SQLite error code.
   */
  readonly attribute long lastError;

  /**
   * The last SQLite error as a string (in english, straight from the
   * sqlite library).
   */
  readonly attribute AUTF8String lastErrorString;

  /**
   * The schema version of the database.  This should not be used until the 
   * database is ready.  The schema will be reported as zero if it is not set.
   */
  attribute long schemaVersion;

  //////////////////////////////////////////////////////////////////////////////
  //// Statement creation

  /**
   * Create a mozIStorageStatement for the given SQL expression.  The
   * expression may use ? to indicate sequential numbered arguments,
   * ?1, ?2 etc. to indicate specific numbered arguments or :name and 
   * $var to indicate named arguments.
   *
   * @param aSQLStatement
   *        The SQL statement to execute.
   * @return a new mozIStorageStatement
   */
  mozIStorageStatement createStatement(in AUTF8String aSQLStatement);

  /**
   * Execute a SQL expression, expecting no arguments.
   *
   * @param aSQLStatement  The SQL statement to execute
   */
  void executeSimpleSQL(in AUTF8String aSQLStatement);

  /**
   * Check if the given table exists.
   *
   * @param aTableName
   *        The table to check
   * @return TRUE if table exists, FALSE otherwise.
   */
  boolean tableExists(in AUTF8String aTableName);

  /**
   * Check if the given index exists.
   *
   * @param aIndexName   The index to check
   * @return TRUE if the index exists, FALSE otherwise.
   */
  boolean indexExists(in AUTF8String aIndexName);

  //////////////////////////////////////////////////////////////////////////////
  //// Transactions

  /**
   * Returns true if a transaction is active on this connection.
   */
  readonly attribute boolean transactionInProgress;

  /**
   * Begin a new transaction.  sqlite default transactions are deferred.
   * If a transaction is active, throws an error.
   */
  void beginTransaction();

  /**
   * Begins a new transaction with the given type.
   */
  const int32_t TRANSACTION_DEFERRED = 0;
  const int32_t TRANSACTION_IMMEDIATE = 1;
  const int32_t TRANSACTION_EXCLUSIVE = 2;
  void beginTransactionAs(in int32_t transactionType);

  /**
   * Commits the current transaction.  If no transaction is active,
   * @throws NS_ERROR_UNEXPECTED.
   * @throws NS_ERROR_NOT_INITIALIZED.
   */
  void commitTransaction();

  /**
   * Rolls back the current transaction.  If no transaction is active,
   * @throws NS_ERROR_UNEXPECTED.
   * @throws NS_ERROR_NOT_INITIALIZED.
   */
  void rollbackTransaction();

  //////////////////////////////////////////////////////////////////////////////
  //// Tables

  /**
   * Create the table with the given name and schema.
   *
   * If the table already exists, NS_ERROR_FAILURE is thrown.
   * (XXX at some point in the future it will check if the schema is
   * the same as what is specified, but that doesn't happen currently.)
   *
   * @param aTableName
   *        The table name to be created, consisting of [A-Za-z0-9_], and
   *        beginning with a letter.
   * @param aTableSchema
   *        The schema of the table; what would normally go between the parens
   *        in a CREATE TABLE statement: e.g., "foo  INTEGER, bar STRING".
   *
   * @throws NS_ERROR_FAILURE
   *         If the table already exists or could not be created for any other
   *         reason.
   */
  void createTable(in string aTableName,
                   in string aTableSchema);

  /**
   * Controls SQLITE_FCNTL_CHUNK_SIZE setting in sqlite. This helps avoid fragmentation
   * by growing/shrinking the database file in SQLITE_FCNTL_CHUNK_SIZE increments. To
   * conserve memory on systems short on storage space, this function will have no effect
   * on mobile devices or if less than 500MiB of space is left available.
   *
   * @param aIncrement
   *        The database file will grow in multiples of chunkSize.
   * @param aDatabaseName
   *        Sqlite database name. "" means pass NULL for zDbName to sqlite3_file_control.
   *        See http://sqlite.org/c3ref/file_control.html for more details.
   * @throws NS_ERROR_FILE_TOO_BIG
   *         If the system is short on storage space.
   */
  void setGrowthIncrement(in int32_t aIncrement, in AUTF8String aDatabaseName);

  /**
   * Enable a predefined virtual table implementation.
   *
   * @param aModuleName
   *        The module to enable. Only "filesystem" is currently supported.
   *
   * @throws NS_ERROR_FAILURE
   *         For unknown module names.
   */
  [noscript] void enableModule(in ACString aModuleName);

  /**
   * Get quota objects.
   *
   * @param[out] aDatabaseQuotaObject
   *             The QuotaObject associated with the database file.
   * @param[out] aJournalQuotaObject
   *             The QuotaObject associated with the journal file.
   *
   * @throws NS_ERROR_NOT_INITIALIZED.
   */
  [noscript] void getQuotaObjects(out QuotaObject aDatabaseQuotaObject,
                                  out QuotaObject aJournalQuotaObject);
};