Implement optional logging of output as suggested by Robert Kern.

IPython/core/history.py

@@ -1,531 +1,550 b''
 """ 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 fnmatch
 import os
 import sqlite3
 
 # Our own packages
 import IPython.utils.io
 
 from IPython.testing import decorators as testdec
 from IPython.utils.io import ask_yes_no
 from IPython.utils.warn import warn
 
 #-----------------------------------------------------------------------------
 # Classes and functions
 #-----------------------------------------------------------------------------
 
 class HistoryManager(object):
     """A class to organize all history-related functionality in one place.
     """
     # Public interface
 
     # An instance of the IPython shell we are attached to
     shell = None
     # A list to hold processed history
     input_hist_parsed = None
     # A list to hold raw history (as typed by user)
     input_hist_raw = None
     # A list of directories visited during session
     dir_hist = None
     # A dict of output history, keyed with ints from the shell's execution count
     output_hist = None
     # String with path to the history file
     hist_file = None
     # The SQLite database
     db = None
     # The number of the current session in the history database
     session_number = None
-    # Number of lines to cache before writing to the database (to save power)
-    #  - if 0, lines will be written instantly.
+    # Should we log output to the database? (default no)
+    db_log_output = False
+    # Write to database every x commands (higher values save disk access & power)
+    #  Values of 1 or less effectively disable caching. 
     db_cache_size = 0
-    # The line cache
-    db_cache = None
+    # The input and output caches
+    db_input_cache = None
+    db_output_cache = None
     
     # 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, _i, _ii, _iii = '','','',''
 
     # A set with 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_commands = None
     
     def __init__(self, shell, load_history=False):
         """Create a new history manager associated with a shell instance.
         
         Parameters
         ----------
         load_history: bool, optional
             If True, history will be loaded from file, and the session
             offset set, so that the next line entered can be retrieved
             as #1.
         """
         # We need a pointer back to the shell for various tasks.
         self.shell = shell
         
         # List of input with multi-line handling. One blank entry so indexing
         # starts from 1.
         self.input_hist_parsed = [""]
         # This one will hold the 'raw' input history, without any
         # pre-processing.  This will allow users to retrieve the input just as
         # it was exactly typed in by the user, with %hist -r.
         self.input_hist_raw = [""]
 
         # list of visited directories
         try:
             self.dir_hist = [os.getcwd()]
         except OSError:
             self.dir_hist = []
 
         # dict of output history
         self.output_hist = {}
 
         # Now the history file
         if shell.profile:
             histfname = 'history-%s' % shell.profile
         else:
             histfname = 'history'
         self.hist_file = os.path.join(shell.ipython_dir, histfname + '.sqlite')
     
         self._i00, self._i, self._ii, self._iii = '','','',''
 
         self._exit_commands = set(['Quit', 'quit', 'Exit', 'exit', '%Quit',
                                    '%quit', '%Exit', '%exit'])
 
         self.init_db()
         
     def init_db(self):
         self.db = sqlite3.connect(self.hist_file)
-        self.db.execute("""CREATE TABLE IF NOT EXISTS history (session integer,
-                        line integer, source text, source_raw 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))""")
         cur = self.db.execute("""SELECT name FROM sqlite_master WHERE
                                 type='table' AND name='singletons'""")
         if not cur.fetchone():
             self.db.execute("""CREATE TABLE singletons
                             (name text PRIMARY KEY, value)""")
             self.db.execute("""INSERT INTO singletons VALUES
                             ('session_number', 1)""")
             self.db.commit()
         cur = self.db.execute("""SELECT value FROM singletons WHERE
                               name='session_number'""")
         self.session_number = cur.fetchone()[0]
         
         #Increment by one for next session.
         self.db.execute("""UPDATE singletons SET value=? WHERE
                         name='session_number'""", (self.session_number+1,))
         self.db.commit()
-        self.db_cache = []
+        self.db_input_cache = []
+        self.db_output_cache = []
                         
     def get_db_history(self, session, start=1, stop=None, raw=True):
         """Retrieve input history from the database by session.
         
         Parameters
         ----------
         session : int
             Session number to retrieve. If negative, counts back from current
             session (so -1 is previous session).
         start : int
             First line to retrieve.
         stop : int
             Last line to retrieve. If None, retrieve to the end of the session.
         raw : bool
             If True, return raw input
             
         Returns
         -------
         An iterator over the desired lines.
         """
         toget = 'source_raw' if raw else 'source'
         if session < 0:
             session += self.session_number
         
         if stop:
             cur = self.db.execute("SELECT " + toget + """ FROM history WHERE
                             session==? AND line BETWEEN ? and ?""",
                             (session, start, stop))
         else:
             cur = self.db.execute("SELECT " + toget + """ FROM history WHERE
                             session==? AND line>=?""", (session, start))
         return (x[0] for x in cur)
                             
     def tail_db_history(self, n=10, raw=True):
         """Get the last n lines from the history database."""
         toget = 'source_raw' if raw else 'source'
         cur = self.db.execute("SELECT " + toget + """ FROM history ORDER BY
                             session DESC, line DESC LIMIT ?""", (n,))
         return (x[0] for x in reversed(cur.fetchall()))
         
     def globsearch_db(self, pattern="*"):
         """Search the database using unix glob-style matching (wildcards * and
         ?, escape using \).
         
         Returns
         -------
         An iterator over tuples: (session, line_number, command)
         """
         return self.db.execute("""SELECT session, line, source_raw FROM history
                                 WHERE source_raw GLOB ?""", (pattern,))
         
     def get_history(self, start=1, stop=None, raw=False, output=True):
         """Get the history list.
 
         Get the input and output history.
 
         Parameters
         ----------
         start : int
             From (prompt number in the current session). Negative numbers count
             back from the end.
         stop : int
             To (prompt number in the current session, exclusive). Negative
             numbers count back from the end, and None goes to the end.
         raw : bool
             If True, return the raw input.
         output : bool
             If True, then return the output as well.
         this_session : bool
             If True, indexing is from 1 at the start of this session.
             If False, indexing is from 1 at the start of the whole history.
 
         Returns
         -------
         If output is True, then return a dict of tuples, keyed by the prompt
         numbers and with values of (input, output). If output is False, then
         a dict, keyed by the prompt number with the values of input.
         """
         if raw:
             input_hist = self.input_hist_raw
         else:
             input_hist = self.input_hist_parsed
         if output:
             output_hist = self.output_hist
             
         n = len(input_hist)
         if start < 0:
             start += n
         if not stop:
             stop = n
         elif stop < 0:
             stop += n
         
         hist = {}
         for i in range(start, stop):
             if output:
                 hist[i] = (input_hist[i], output_hist.get(i))
             else:
                 hist[i] = input_hist[i]
         return hist
 
     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
             
         # do not store exit/quit commands
         if source_raw.strip() in self._exit_commands:
             return
         
         self.input_hist_parsed.append(source.rstrip())
         self.input_hist_raw.append(source_raw.rstrip())
         
-        db_row = (self.session_number, line_num, source, source_raw)
-        if self.db_cache_size:        # Cache before writing
-            self.db_cache.append(db_row)
-            if len(self.db_cache) > self.db_cache_size:
+        self.db_input_cache.append((self.session_number, line_num,
+                                    source, source_raw))
+        # Trigger to flush cache and write to DB.
+        if len(self.db_input_cache) >= self.db_cache_size:
                 self.writeout_cache()
-        else:                         # Instant write
-            with self.db:
-              self.db.execute("INSERT INTO history VALUES (?, ?, ?, ?)", db_row)
 
         # 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, output):
+        if not self.db_log_output:
+            return
+        db_row = (self.session_number, line_num, output)
+        if self.db_cache_size > 1:
+            self.db_output_cache.append(db_row)
+        else:
+          with self.db:
+            self.db.execute("INSERT INTO output_history VALUES (?,?,?)", db_row)
+        
     def writeout_cache(self):
         with self.db:
             self.db.executemany("INSERT INTO history VALUES (?, ?, ?, ?)",
-                                self.db_cache)
-        self.db_cache = []
+                                self.db_input_cache)
+            self.db.executemany("INSERT INTO output_history VALUES (?, ?, ?)",
+                                self.db_output_cache)
+        self.db_input_cache = []
+        self.db_output_cache = []
 
     def sync_inputs(self):
         """Ensure raw and translated histories have same length."""
         lr = len(self.input_hist_raw)
         lp = len(self.input_hist_parsed)
         if lp < lr:
             self.input_hist_raw[:lr-lp] = []
         elif lr < lp:
             self.input_hist_parsed[:lp-lr] = []
 
     def reset(self):
         """Clear all histories managed by this object."""
         self.input_hist_parsed[:] = []
         self.input_hist_raw[:] = []
         self.output_hist.clear()
         # The directory history can't be completely empty
         self.dir_hist[:] = [os.getcwd()]
 
 @testdec.skip_doctest
 def magic_history(self, parameter_s = ''):
     """Print input history (_i<n> 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.
 
     With -n, each input's number <n> is shown, and is accessible as the
     automatically generated variable _i<n> as well as In[<n>].  Multi-line
     statements are printed starting at a new line for easy copy/paste.
 
     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).
 
       -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,'gnoptsrf:',mode='list')
     
     # For brevity
     history_manager = self.shell.history_manager
 
     # Check if output to specific file was requested.
     try:
         outfname = opts['f']
     except KeyError:
         outfile = IPython.utils.io.Term.cout  # default
         # We don't want to close stdout at the end!
         close_at_end = False
     else:
         if os.path.exists(outfname):
             if not ask_yes_no("File %r exists. Overwrite?" % outfname): 
                 print('Aborting.')
                 return
 
         outfile = open(outfname,'w')
         close_at_end = True
     
     print_nums = 'n' in opts
     print_outputs = '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:
         start = 1; stop = None
         parts = parameter_s.split(None, 1)
         if len(parts) == 1:
             parts += '*'
         head, pattern = parts
         pattern = "*" + pattern + "*"
     elif len(args) == 0:
         start = 1; stop = None
     elif len(args) == 1:
         start = -int(args[0]); stop=None
     elif len(args) == 2:
         start = int(args[0]); stop = int(args[1])
     else:
         warn('%hist takes 0, 1 or 2 arguments separated by spaces.')
         print(self.magic_hist.__doc__, file=IPython.utils.io.Term.cout)
         return
         
     hist = history_manager.get_history(start, stop, raw, print_outputs)
     
     width = len(str(max(hist.iterkeys())))
     line_sep = ['','\n']
     
     found = False
     if pattern is not None:
         for session, line, s in history_manager.globsearch_db(pattern):
             print("%d#%d: %s" %(session, line, s.expandtabs(4)), file=outfile)
             found = True
     
     if found:
         print("===", file=outfile)
         print("shadow history ends, fetch by %rep session#line",
               file=outfile)
         print("=== start of normal history ===", file=outfile)
         
     for in_num, inline in sorted(hist.iteritems()):
         # 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 print_outputs:
             inline, output = inline
         inline = inline.expandtabs(4).rstrip()
 
         if pattern is not None and not fnmatch.fnmatch(inline, pattern):
             continue
             
         multiline = "\n" in inline
         if print_nums:
             print('%s:%s' % (str(in_num).ljust(width), line_sep[multiline]),
                   file=outfile, end='')
         if pyprompts:
             print(">>> ", end="", file=outfile)
             if multiline:
                 inline = "\n... ".join(inline.splitlines()) + "\n..."
         print(inline, file=outfile)
         if print_outputs and output:
             print(repr(output), file=outfile)
 
     if close_at_end:
         outfile.close()
 
 # %hist is an alternative name
 magic_hist = magic_history
 
 
 def rep_f(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::
     
         $ l = ["hei", "vaan"]       
         $ "".join(l)        
         ==> heivaan        
         $ %rep        
         $ heivaan_ <== cursor blinking    
     
     %rep 45
     
     Place history line 45 to next input prompt. Use %hist to find out the
     number.
     
     %rep 1-4 6-7 3
     
     Repeat the specified lines immediately. Input slice syntax is the same as
     in %macro and %save.
     
     %rep foo
     
     Place the most recent line that has the substring "foo" to next input.
     (e.g. 'svn ci -m foobar').    
     """
     
     opts,args = self.parse_options(arg,'',mode='list')
     if not args:
         self.set_next_input(str(self.shell.user_ns["_"]))
         return
 
     if len(args) == 1 and not '-' in args[0]:
         arg = args[0]
         if len(arg) > 1 and arg.startswith('0'):
             # get from shadow hist
             num = int(arg[1:])
             line = self.shell.shadowhist.get(num)
             self.set_next_input(str(line))
             return
         try:
             num = int(args[0])
             self.set_next_input(str(self.shell.input_hist_raw[num]).rstrip())
             return
         except ValueError:
             pass
         
         for h in reversed(self.shell.input_hist_raw):
             if 'rep' in h:
                 continue
             if fnmatch.fnmatch(h,'*' + arg + '*'):
                 self.set_next_input(str(h).rstrip())
                 return
         
     try:
         lines = self.extract_input_slices(args, True)
         print("lines", lines)
         self.run_cell(lines)
     except ValueError:
         print("Not found in recent history:", args)
 
 
 def init_ipython(ip):
     ip.define_magic("rep",rep_f)        
     ip.define_magic("hist",magic_hist)            
     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')