[spp] [PATCH] controller: add history and redo commands

[ogawa.yasufumi at lab.ntt.co.jp]

From: Yasufumi Ogawa <ogawa.yasufumi at lab.ntt.co.jp>

SPP controller has no history for commands. It is useful if user inputs
several commands and check it step by step. It is also useful to redo
the commands by referring the history.

This update is to add history and redo commands. History command shows
the list of command with index number. Command history is saved as
'.spp_history' which is created in the project root directory.

  spp > history
    1  sec 1;status
    2  pri;status
    ...

User can redo a previous command with index number.

  spp > redo 1  # run 'sec 1;status' from redo command
  - status: running
  - port:
    - phy:0 -> ring:0

Signed-off-by: Yasufumi Ogawa <ogawa.yasufumi at lab.ntt.co.jp>
---
 .gitignore              |  1 +
 src/controller/shell.py | 92 ++++++++++++++++++++++++++++++++++++++++++++++++-
 2 files changed, 92 insertions(+), 1 deletion(-)

diff --git a/.gitignore b/.gitignore
index 37bba66..b31ab54 100644
--- a/.gitignore
+++ b/.gitignore
@@ -5,3 +5,4 @@ docs/guides/_build/*
 docs/guides/images/**/*.pdf
 src/controller/3rd_party/*
 tools/sppc/build/*/*/env.sh
+.spp_history
diff --git a/src/controller/shell.py b/src/controller/shell.py
index fb30d5d..393699c 100644
--- a/src/controller/shell.py
+++ b/src/controller/shell.py
@@ -9,6 +9,7 @@ import json
 import os
 from queue import Empty
 import re
+import readline
 from .shell_lib import common
 from . import spp_common
 from .spp_common import logger
@@ -19,6 +20,8 @@ from . import topo
 class Shell(cmd.Cmd, object):
     """SPP command prompt"""
 
+    hist_file = '.spp_history'
+
     intro = 'Welcome to the spp.   Type help or ? to list commands.\n'
     prompt = 'spp > '
     recorded_file = None
@@ -35,10 +38,18 @@ class Shell(cmd.Cmd, object):
     SEC_SUBCMDS = ['vhost', 'ring', 'pcap', 'nullpmd']
     BYE_CMDS = ['sec', 'all']
 
+    HIST_EXCEPT = ['bye', 'exit', 'history', 'redo']
+
     PLUGIN_DIR = 'command'
     subgraphs = {}
     topo_size = '60%'
 
+    # setup history file
+    if os.path.exists(hist_file):
+        readline.read_history_file(hist_file)
+    else:
+        readline.write_history_file(hist_file)
+
     def default(self, line):
         """Define defualt behaviour
 
@@ -48,6 +59,7 @@ class Shell(cmd.Cmd, object):
 
         if common.is_comment_line(line):
             print("%s" % line.strip())
+
         else:
             super(Shell, self).default(line)
 
@@ -59,6 +71,25 @@ class Shell(cmd.Cmd, object):
         """
         pass
 
+    def clean_hist_file(self):
+        """Remove useless entries in history file."""
+
+        entries = []
+
+        try:
+            for line in open(self.hist_file):
+                l = line.strip()
+                if not (l.split(' ')[0] in self.HIST_EXCEPT):
+                    entries.append(l)
+            f = open(self.hist_file, "w+")
+            contents = '\n'.join(entries)
+            contents += '\n'
+            f.write(contents)
+            f.close()
+        except IOError:
+            print('Error: Cannot open history file "%s"' %
+                    self.hist_file)
+
     def close_all_secondary(self):
         """Terminate all secondary processes"""
 
@@ -587,7 +618,7 @@ class Shell(cmd.Cmd, object):
         return completions
 
     def do_cat(self, arg):
-        """View contents of a file
+        """View contents of a file.
 
         spp > cat file
         """
@@ -597,6 +628,64 @@ class Shell(cmd.Cmd, object):
         else:
             print("No such a directory.")
 
+    def do_redo(self, args):
+        """Execute command of index of history."""
+
+        idx = int(args)
+        cmdline = None
+        cnt = 1
+        try:
+            for line in open(self.hist_file):
+                if cnt == idx:
+                    cmdline = line.strip()
+                    break
+                cnt += 1
+
+            if cmdline.find('pri;') > -1:
+                cmdline = cmdline.replace(';', ' ;')
+                print(cmdline)
+            cmd_ary = cmdline.split(' ')
+            cmd = cmd_ary.pop(0)
+            cmd_options = ' '.join(cmd_ary)
+            eval('self.do_%s(cmd_options)' % cmd)
+        except IOError:
+            print('Error: Cannot open history file "%s"' %
+                    self.hist_file)
+
+    def do_history(self, arg):
+        """Show history.
+
+        spp > history
+          1  ls
+          2  cat file.txt
+          ...
+        """
+
+        # flush all of history to the hist_file.
+        readline.write_history_file(self.hist_file)
+
+        # remove commands defined in `self.HIST_EXCEPT`
+        self.clean_hist_file()
+
+        try:
+            f = open(self.hist_file)
+
+            # setup output format
+            nof_lines = len(f.readlines())
+            f.seek(0)
+            lines_digit = len(str(nof_lines))
+            hist_format = '  %' + str(lines_digit) + 'd  %s'
+
+            cnt = 1
+            for line in f:
+                l = line.strip()
+                print(hist_format % (cnt, l))
+                cnt += 1
+            f.close()
+        except IOError:
+            print('Error: Cannot open history file "%s"' %
+                    self.hist_file)
+
     def complete_cat(self, text, line, begidx, endidx):
         return common.compl_common(text, line)
 
@@ -621,6 +710,7 @@ class Shell(cmd.Cmd, object):
 
         spp > exit
         """
+
         self.close()
         print('Thank you for using Soft Patch Panel')
         return True
-- 
2.7.4