""" History related magics and functionality """ #----------------------------------------------------------------------------- # Copyright (C) 2010 The IPython Development Team. # # Distributed under the terms of the BSD License. # # The full license is in the file COPYING.txt, distributed with this software. #----------------------------------------------------------------------------- #----------------------------------------------------------------------------- # Imports #----------------------------------------------------------------------------- from __future__ import print_function # Stdlib imports import atexit import datetime import os import re import sqlite3 import threading # Our own packages from IPython.config.configurable import Configurable from IPython.testing.skipdoctest import skip_doctest from IPython.utils import io from IPython.utils.traitlets import Bool, Dict, Instance, Int, List, Unicode from IPython.utils.warn import warn #----------------------------------------------------------------------------- # Classes and functions #----------------------------------------------------------------------------- class HistoryManager(Configurable): """A class to organize all history-related functionality in one place. """ # Public interface # An instance of the IPython shell we are attached to shell = Instance('IPython.core.interactiveshell.InteractiveShellABC') # Lists to hold processed and raw history. These start with a blank entry # so that we can index them starting from 1 input_hist_parsed = List([""]) input_hist_raw = List([""]) # A list of directories visited during session dir_hist = List() def _dir_hist_default(self): try: return [os.getcwdu()] except OSError: return [] # A dict of output history, keyed with ints from the shell's # execution count. output_hist = Dict() # The text/plain repr of outputs. output_hist_reprs = Dict() # String holding the path to the history file hist_file = Unicode(config=True) # The SQLite database db = Instance(sqlite3.Connection) # The number of the current session in the history database session_number = Int() # Should we log output to the database? (default no) db_log_output = Bool(False, config=True) # Write to database every x commands (higher values save disk access & power) # Values of 1 or less effectively disable caching. db_cache_size = Int(0, config=True) # The input and output caches db_input_cache = List() db_output_cache = List() # History saving in separate thread save_thread = Instance('IPython.core.history.HistorySavingThread') # N.B. Event is a function returning an instance of _Event. save_flag = Instance(threading._Event) # Private interface # Variables used to store the three last inputs from the user. On each new # history update, we populate the user's namespace with these, shifted as # necessary. _i00 = Unicode(u'') _i = Unicode(u'') _ii = Unicode(u'') _iii = Unicode(u'') # A regex matching all forms of the exit command, so that we don't store # them in the history (it's annoying to rewind the first entry and land on # an exit call). _exit_re = re.compile(r"(exit|quit)(\s*\(.*\))?$") def __init__(self, shell, config=None, **traits): """Create a new history manager associated with a shell instance. """ # We need a pointer back to the shell for various tasks. super(HistoryManager, self).__init__(shell=shell, config=config, **traits) if self.hist_file == u'': # No one has set the hist_file, yet. histfname = 'history' self.hist_file = os.path.join(shell.profile_dir.location, histfname + '.sqlite') try: self.init_db() except sqlite3.DatabaseError: if os.path.isfile(self.hist_file): # Try to move the file out of the way. newpath = os.path.join(self.shell.profile_dir.location, "hist-corrupt.sqlite") os.rename(self.hist_file, newpath) print("ERROR! History file wasn't a valid SQLite database.", "It was moved to %s" % newpath, "and a new file created.") self.init_db() else: # The hist_file is probably :memory: or something else. raise self.save_flag = threading.Event() self.db_input_cache_lock = threading.Lock() self.db_output_cache_lock = threading.Lock() self.save_thread = HistorySavingThread(self) self.save_thread.start() self.new_session() def init_db(self): """Connect to the database, and create tables if necessary.""" self.db = sqlite3.connect(self.hist_file) self.db.execute("""CREATE TABLE IF NOT EXISTS sessions (session integer primary key autoincrement, start timestamp, end timestamp, num_cmds integer, remark text)""") self.db.execute("""CREATE TABLE IF NOT EXISTS history (session integer, line integer, source text, source_raw text, PRIMARY KEY (session, line))""") # Output history is optional, but ensure the table's there so it can be # enabled later. self.db.execute("""CREATE TABLE IF NOT EXISTS output_history (session integer, line integer, output text, PRIMARY KEY (session, line))""") self.db.commit() def new_session(self, conn=None): """Get a new session number.""" if conn is None: conn = self.db with conn: cur = conn.execute("""INSERT INTO sessions VALUES (NULL, ?, NULL, NULL, "") """, (datetime.datetime.now(),)) self.session_number = cur.lastrowid def end_session(self): """Close the database session, filling in the end time and line count.""" self.writeout_cache() with self.db: self.db.execute("""UPDATE sessions SET end=?, num_cmds=? WHERE session==?""", (datetime.datetime.now(), len(self.input_hist_parsed)-1, self.session_number)) self.session_number = 0 def name_session(self, name): """Give the current session a name in the history database.""" with self.db: self.db.execute("UPDATE sessions SET remark=? WHERE session==?", (name, self.session_number)) def reset(self, new_session=True): """Clear the session history, releasing all object references, and optionally open a new session.""" self.output_hist.clear() # The directory history can't be completely empty self.dir_hist[:] = [os.getcwdu()] if new_session: if self.session_number: self.end_session() self.input_hist_parsed[:] = [""] self.input_hist_raw[:] = [""] self.new_session() ## ------------------------------- ## Methods for retrieving history: ## ------------------------------- def _run_sql(self, sql, params, raw=True, output=False): """Prepares and runs an SQL query for the history database. Parameters ---------- sql : str Any filtering expressions to go after SELECT ... FROM ... params : tuple Parameters passed to the SQL query (to replace "?") raw, output : bool See :meth:`get_range` Returns ------- Tuples as :meth:`get_range` """ toget = 'source_raw' if raw else 'source' sqlfrom = "history" if output: sqlfrom = "history LEFT JOIN output_history USING (session, line)" toget = "history.%s, output_history.output" % toget cur = self.db.execute("SELECT session, line, %s FROM %s " %\ (toget, sqlfrom) + sql, params) if output: # Regroup into 3-tuples, and parse JSON return ((ses, lin, (inp, out)) for ses, lin, inp, out in cur) return cur def get_tail(self, n=10, raw=True, output=False, include_latest=False): """Get the last n lines from the history database. Parameters ---------- n : int The number of lines to get raw, output : bool See :meth:`get_range` include_latest : bool If False (default), n+1 lines are fetched, and the latest one is discarded. This is intended to be used where the function is called by a user command, which it should not return. Returns ------- Tuples as :meth:`get_range` """ self.writeout_cache() if not include_latest: n += 1 cur = self._run_sql("ORDER BY session DESC, line DESC LIMIT ?", (n,), raw=raw, output=output) if not include_latest: return reversed(list(cur)[1:]) return reversed(list(cur)) def search(self, pattern="*", raw=True, search_raw=True, output=False): """Search the database using unix glob-style matching (wildcards * and ?). Parameters ---------- pattern : str The wildcarded pattern to match when searching search_raw : bool If True, search the raw input, otherwise, the parsed input raw, output : bool See :meth:`get_range` Returns ------- Tuples as :meth:`get_range` """ tosearch = "source_raw" if search_raw else "source" if output: tosearch = "history." + tosearch self.writeout_cache() return self._run_sql("WHERE %s GLOB ?" % tosearch, (pattern,), raw=raw, output=output) def _get_range_session(self, start=1, stop=None, raw=True, output=False): """Get input and output history from the current session. Called by get_range, and takes similar parameters.""" input_hist = self.input_hist_raw if raw else self.input_hist_parsed n = len(input_hist) if start < 0: start += n if not stop: stop = n elif stop < 0: stop += n for i in range(start, stop): if output: line = (input_hist[i], self.output_hist_reprs.get(i)) else: line = input_hist[i] yield (0, i, line) def get_range(self, session=0, start=1, stop=None, raw=True,output=False): """Retrieve input by session. Parameters ---------- session : int Session number to retrieve. The current session is 0, and negative numbers count back from current session, so -1 is previous session. start : int First line to retrieve. stop : int End of line range (excluded from output itself). If None, retrieve to the end of the session. raw : bool If True, return untranslated input output : bool If True, attempt to include output. This will be 'real' Python objects for the current session, or text reprs from previous sessions if db_log_output was enabled at the time. Where no output is found, None is used. Returns ------- An iterator over the desired lines. Each line is a 3-tuple, either (session, line, input) if output is False, or (session, line, (input, output)) if output is True. """ if session == 0 or session==self.session_number: # Current session return self._get_range_session(start, stop, raw, output) if session < 0: session += self.session_number if stop: lineclause = "line >= ? AND line < ?" params = (session, start, stop) else: lineclause = "line>=?" params = (session, start) return self._run_sql("WHERE session==? AND %s""" % lineclause, params, raw=raw, output=output) def get_range_by_str(self, rangestr, raw=True, output=False): """Get lines of history from a string of ranges, as used by magic commands %hist, %save, %macro, etc. Parameters ---------- rangestr : str A string specifying ranges, e.g. "5 ~2/1-4". See :func:`magic_history` for full details. raw, output : bool As :meth:`get_range` Returns ------- Tuples as :meth:`get_range` """ for sess, s, e in extract_hist_ranges(rangestr): for line in self.get_range(sess, s, e, raw=raw, output=output): yield line ## ---------------------------- ## Methods for storing history: ## ---------------------------- def store_inputs(self, line_num, source, source_raw=None): """Store source and raw input in history and create input cache variables _i*. Parameters ---------- line_num : int The prompt number of this input. source : str Python input. source_raw : str, optional If given, this is the raw input without any IPython transformations applied to it. If not given, ``source`` is used. """ if source_raw is None: source_raw = source source = source.rstrip('\n') source_raw = source_raw.rstrip('\n') # do not store exit/quit commands if self._exit_re.match(source_raw.strip()): return self.input_hist_parsed.append(source) self.input_hist_raw.append(source_raw) with self.db_input_cache_lock: self.db_input_cache.append((line_num, source, source_raw)) # Trigger to flush cache and write to DB. if len(self.db_input_cache) >= self.db_cache_size: self.save_flag.set() # update the auto _i variables self._iii = self._ii self._ii = self._i self._i = self._i00 self._i00 = source_raw # hackish access to user namespace to create _i1,_i2... dynamically new_i = '_i%s' % line_num to_main = {'_i': self._i, '_ii': self._ii, '_iii': self._iii, new_i : self._i00 } self.shell.user_ns.update(to_main) def store_output(self, line_num): """If database output logging is enabled, this saves all the outputs from the indicated prompt number to the database. It's called by run_cell after code has been executed. Parameters ---------- line_num : int The line number from which to save outputs """ if (not self.db_log_output) or (line_num not in self.output_hist_reprs): return output = self.output_hist_reprs[line_num] with self.db_output_cache_lock: self.db_output_cache.append((line_num, output)) if self.db_cache_size <= 1: self.save_flag.set() def _writeout_input_cache(self, conn): with conn: for line in self.db_input_cache: conn.execute("INSERT INTO history VALUES (?, ?, ?, ?)", (self.session_number,)+line) def _writeout_output_cache(self, conn): with conn: for line in self.db_output_cache: conn.execute("INSERT INTO output_history VALUES (?, ?, ?)", (self.session_number,)+line) def writeout_cache(self, conn=None): """Write any entries in the cache to the database.""" if conn is None: conn = self.db with self.db_input_cache_lock: try: self._writeout_input_cache(conn) except sqlite3.IntegrityError: self.new_session(conn) print("ERROR! Session/line number was not unique in", "database. History logging moved to new session", self.session_number) try: # Try writing to the new session. If this fails, don't recurse self._writeout_input_cache(conn) except sqlite3.IntegrityError: pass finally: self.db_input_cache = [] with self.db_output_cache_lock: try: self._writeout_output_cache(conn) except sqlite3.IntegrityError: print("!! Session/line number for output was not unique", "in database. Output will not be stored.") finally: self.db_output_cache = [] class HistorySavingThread(threading.Thread): """This thread takes care of writing history to the database, so that the UI isn't held up while that happens. It waits for the HistoryManager's save_flag to be set, then writes out the history cache. The main thread is responsible for setting the flag when the cache size reaches a defined threshold.""" daemon = True stop_now = False def __init__(self, history_manager): super(HistorySavingThread, self).__init__() self.history_manager = history_manager atexit.register(self.stop) def run(self): # We need a separate db connection per thread: try: self.db = sqlite3.connect(self.history_manager.hist_file) while True: self.history_manager.save_flag.wait() if self.stop_now: return self.history_manager.save_flag.clear() self.history_manager.writeout_cache(self.db) except Exception as e: print(("The history saving thread hit an unexpected error (%s)." "History will not be written to the database.") % repr(e)) def stop(self): """This can be called from the main thread to safely stop this thread. Note that it does not attempt to write out remaining history before exiting. That should be done by calling the HistoryManager's end_session method.""" self.stop_now = True self.history_manager.save_flag.set() self.join() # To match, e.g. ~5/8-~2/3 range_re = re.compile(r""" ((?P~?\d+)/)? (?P\d+) # Only the start line num is compulsory ((?P[\-:]) ((?P~?\d+)/)? (?P\d+))? $""", re.VERBOSE) def extract_hist_ranges(ranges_str): """Turn a string of history ranges into 3-tuples of (session, start, stop). Examples -------- list(extract_input_ranges("~8/5-~7/4 2")) [(-8, 5, None), (-7, 1, 4), (0, 2, 3)] """ for range_str in ranges_str.split(): rmatch = range_re.match(range_str) if not rmatch: continue start = int(rmatch.group("start")) end = rmatch.group("end") end = int(end) if end else start+1 # If no end specified, get (a, a+1) if rmatch.group("sep") == "-": # 1-3 == 1:4 --> [1, 2, 3] end += 1 startsess = rmatch.group("startsess") or "0" endsess = rmatch.group("endsess") or startsess startsess = int(startsess.replace("~","-")) endsess = int(endsess.replace("~","-")) assert endsess >= startsess if endsess == startsess: yield (startsess, start, end) continue # Multiple sessions in one range: yield (startsess, start, None) for sess in range(startsess+1, endsess): yield (sess, 1, None) yield (endsess, 1, end) def _format_lineno(session, line): """Helper function to format line numbers properly.""" if session == 0: return str(line) return "%s#%s" % (session, line) @skip_doctest def magic_history(self, parameter_s = ''): """Print input history (_i variables), with most recent last. %history -> print at most 40 inputs (some may be multi-line)\\ %history n -> print at most n inputs\\ %history n1 n2 -> print inputs between n1 and n2 (n2 not included)\\ By default, input history is printed without line numbers so it can be directly pasted into an editor. Use -n to show them. Ranges of history can be indicated using the syntax: 4 : Line 4, current session 4-6 : Lines 4-6, current session 243/1-5: Lines 1-5, session 243 ~2/7 : Line 7, session 2 before current ~8/1-~6/5 : From the first line of 8 sessions ago, to the fifth line of 6 sessions ago. Multiple ranges can be entered, separated by spaces The same syntax is used by %macro, %save, %edit, %rerun Options: -n: print line numbers for each input. This feature is only available if numbered prompts are in use. -o: also print outputs for each input. -p: print classic '>>>' python prompts before each input. This is useful for making documentation, and in conjunction with -o, for producing doctest-ready output. -r: (default) print the 'raw' history, i.e. the actual commands you typed. -t: print the 'translated' history, as IPython understands it. IPython filters your input and converts it all into valid Python source before executing it (things like magics or aliases are turned into function calls, for example). With this option, you'll see the native history instead of the user-entered version: '%cd /' will be seen as 'get_ipython().magic("%cd /")' instead of '%cd /'. -g: treat the arg as a pattern to grep for in (full) history. This includes the saved history (almost all commands ever written). Use '%hist -g' to show full saved history (may be very long). -l: get the last n lines from all sessions. Specify n as a single arg, or the default is the last 10 lines. -f FILENAME: instead of printing the output to the screen, redirect it to the given file. The file is always overwritten, though IPython asks for confirmation first if it already exists. Examples -------- :: In [6]: %hist -n 4 6 4:a = 12 5:print a**2 """ if not self.shell.displayhook.do_full_cache: print('This feature is only available if numbered prompts are in use.') return opts,args = self.parse_options(parameter_s,'noprtglf:',mode='string') # For brevity history_manager = self.shell.history_manager def _format_lineno(session, line): """Helper function to format line numbers properly.""" if session in (0, history_manager.session_number): return str(line) return "%s/%s" % (session, line) # Check if output to specific file was requested. try: outfname = opts['f'] except KeyError: outfile = io.stdout # default # We don't want to close stdout at the end! close_at_end = False else: if os.path.exists(outfname): if not io.ask_yes_no("File %r exists. Overwrite?" % outfname): print('Aborting.') return outfile = open(outfname,'w') close_at_end = True print_nums = 'n' in opts get_output = 'o' in opts pyprompts = 'p' in opts # Raw history is the default raw = not('t' in opts) default_length = 40 pattern = None if 'g' in opts: # Glob search pattern = "*" + args + "*" if args else "*" hist = history_manager.search(pattern, raw=raw, output=get_output) print_nums = True elif 'l' in opts: # Get 'tail' try: n = int(args) except ValueError, IndexError: n = 10 hist = history_manager.get_tail(n, raw=raw, output=get_output) else: if args: # Get history by ranges hist = history_manager.get_range_by_str(args, raw, get_output) else: # Just get history for the current session hist = history_manager.get_range(raw=raw, output=get_output) # We could be displaying the entire history, so let's not try to pull it # into a list in memory. Anything that needs more space will just misalign. width = 4 for session, lineno, inline in hist: # Print user history with tabs expanded to 4 spaces. The GUI clients # use hard tabs for easier usability in auto-indented code, but we want # to produce PEP-8 compliant history for safe pasting into an editor. if get_output: inline, output = inline inline = inline.expandtabs(4).rstrip() multiline = "\n" in inline line_sep = '\n' if multiline else ' ' if print_nums: print('%s:%s' % (_format_lineno(session, lineno).rjust(width), line_sep), file=outfile, end='') if pyprompts: print(">>> ", end="", file=outfile) if multiline: inline = "\n... ".join(inline.splitlines()) + "\n..." print(inline, file=outfile) if get_output and output: print(output, file=outfile) if close_at_end: outfile.close() def magic_rep(self, arg): r""" Repeat a command, or get command to input line for editing - %rep (no arguments): Place a string version of last computation result (stored in the special '_' variable) to the next input prompt. Allows you to create elaborate command lines without using copy-paste:: In[1]: l = ["hei", "vaan"] In[2]: "".join(l) Out[2]: heivaan In[3]: %rep In[4]: heivaan_ <== cursor blinking %rep 45 Place history line 45 on the next input prompt. Use %hist to find out the number. %rep 1-4 Combine the specified lines into one cell, and place it on the next input prompt. See %history for the slice syntax. %rep foo+bar If foo+bar can be evaluated in the user namespace, the result is placed at the next input prompt. Otherwise, the history is searched for lines which contain that substring, and the most recent one is placed at the next input prompt. """ if not arg: # Last output self.set_next_input(str(self.shell.user_ns["_"])) return # Get history range histlines = self.history_manager.get_range_by_str(arg) cmd = "\n".join(x[2] for x in histlines) if cmd: self.set_next_input(cmd.rstrip()) return try: # Variable in user namespace cmd = str(eval(arg, self.shell.user_ns)) except Exception: # Search for term in history histlines = self.history_manager.search("*"+arg+"*") for h in reversed([x[2] for x in histlines]): if 'rep' in h: continue self.set_next_input(h.rstrip()) return else: self.set_next_input(cmd.rstrip()) print("Couldn't evaluate or find in history:", arg) def magic_rerun(self, parameter_s=''): """Re-run previous input By default, you can specify ranges of input history to be repeated (as with %history). With no arguments, it will repeat the last line. Options: -l : Repeat the last n lines of input, not including the current command. -g foo : Repeat the most recent line which contains foo """ opts, args = self.parse_options(parameter_s, 'l:g:', mode='string') if "l" in opts: # Last n lines n = int(opts['l']) hist = self.history_manager.get_tail(n) elif "g" in opts: # Search p = "*"+opts['g']+"*" hist = list(self.history_manager.search(p)) for l in reversed(hist): if "rerun" not in l[2]: hist = [l] # The last match which isn't a %rerun break else: hist = [] # No matches except %rerun elif args: # Specify history ranges hist = self.history_manager.get_range_by_str(args) else: # Last line hist = self.history_manager.get_tail(1) hist = [x[2] for x in hist] if not hist: print("No lines in history match specification") return histlines = "\n".join(hist) print("=== Executing: ===") print(histlines) print("=== Output: ===") self.run_cell("\n".join(hist), store_history=False) def init_ipython(ip): ip.define_magic("rep", magic_rep) ip.define_magic("recall", magic_rep) ip.define_magic("rerun", magic_rerun) ip.define_magic("hist",magic_history) # Alternative name ip.define_magic("history",magic_history) # XXX - ipy_completers are in quarantine, need to be updated to new apis #import ipy_completers #ipy_completers.quick_completer('%hist' ,'-g -t -r -n')