1
2
3
4
5
6 import sys, re
7
9 """
10 A class that can be used to portably generate formatted output to
11 a terminal.
12
13 `TerminalController` defines a set of instance variables whose
14 values are initialized to the control sequence necessary to
15 perform a given action. These can be simply included in normal
16 output to the terminal:
17
18 >>> term = TerminalController()
19 >>> print 'This is '+term.GREEN+'green'+term.NORMAL
20
21 Alternatively, the `render()` method can used, which replaces
22 '${action}' with the string required to perform 'action':
23
24 >>> term = TerminalController()
25 >>> print term.render('This is ${GREEN}green${NORMAL}')
26
27 If the terminal doesn't support a given action, then the value of
28 the corresponding instance variable will be set to ''. As a
29 result, the above code will still work on terminals that do not
30 support color, except that their output will not be colored.
31 Also, this means that you can test whether the terminal supports a
32 given action by simply testing the truth value of the
33 corresponding instance variable:
34
35 >>> term = TerminalController()
36 >>> if term.CLEAR_SCREEN:
37 ... print 'This terminal supports clearning the screen.'
38
39 Finally, if the width and height of the terminal are known, then
40 they will be stored in the `COLS` and `LINES` attributes.
41 """
42
43 BOL = ''
44 UP = ''
45 DOWN = ''
46 LEFT = ''
47 RIGHT = ''
48
49
50 CLEAR_SCREEN = ''
51 CLEAR_EOL = ''
52 CLEAR_BOL = ''
53 CLEAR_EOS = ''
54
55
56 BOLD = ''
57 BLINK = ''
58 DIM = ''
59 REVERSE = ''
60 NORMAL = ''
61
62
63 HIDE_CURSOR = ''
64 SHOW_CURSOR = ''
65
66
67 COLS = None
68 LINES = None
69
70
71 BLACK = BLUE = GREEN = CYAN = RED = MAGENTA = YELLOW = WHITE = ''
72
73
74 BG_BLACK = BG_BLUE = BG_GREEN = BG_CYAN = ''
75 BG_RED = BG_MAGENTA = BG_YELLOW = BG_WHITE = ''
76
77 _STRING_CAPABILITIES = """
78 BOL=cr UP=cuu1 DOWN=cud1 LEFT=cub1 RIGHT=cuf1
79 CLEAR_SCREEN=clear CLEAR_EOL=el CLEAR_BOL=el1 CLEAR_EOS=ed BOLD=bold
80 BLINK=blink DIM=dim REVERSE=rev UNDERLINE=smul NORMAL=sgr0
81 HIDE_CURSOR=cinvis SHOW_CURSOR=cnorm""".split()
82 _COLORS = """BLACK BLUE GREEN CYAN RED MAGENTA YELLOW WHITE""".split()
83 _ANSICOLORS = "BLACK RED GREEN YELLOW BLUE MAGENTA CYAN WHITE".split()
84
85 - def __init__(self, term_stream=sys.stdout):
86 """
87 Create a `TerminalController` and initialize its attributes
88 with appropriate values for the current terminal.
89 `term_stream` is the stream that will be used for terminal
90 output; if this stream is not a tty, then the terminal is
91 assumed to be a dumb terminal (i.e., have no capabilities).
92 """
93
94 try: import curses
95 except: return
96
97
98 if not term_stream.isatty(): return
99
100
101
102 try: curses.setupterm()
103 except: return
104
105
106 self.COLS = curses.tigetnum('cols')
107 self.LINES = curses.tigetnum('lines')
108
109
110 for capability in self._STRING_CAPABILITIES:
111 (attrib, cap_name) = capability.split('=')
112 setattr(self, attrib, self._tigetstr(cap_name) or '')
113
114
115 set_fg = self._tigetstr('setf')
116 if set_fg:
117 for i,color in zip(range(len(self._COLORS)), self._COLORS):
118 setattr(self, color, curses.tparm(set_fg, i) or '')
119 set_fg_ansi = self._tigetstr('setaf')
120 if set_fg_ansi:
121 for i,color in zip(range(len(self._ANSICOLORS)), self._ANSICOLORS):
122 setattr(self, color, curses.tparm(set_fg_ansi, i) or '')
123 set_bg = self._tigetstr('setb')
124 if set_bg:
125 for i,color in zip(range(len(self._COLORS)), self._COLORS):
126 setattr(self, 'BG_'+color, curses.tparm(set_bg, i) or '')
127 set_bg_ansi = self._tigetstr('setab')
128 if set_bg_ansi:
129 for i,color in zip(range(len(self._ANSICOLORS)), self._ANSICOLORS):
130 setattr(self, 'BG_'+color, curses.tparm(set_bg_ansi, i) or '')
131
133
134
135
136 import curses
137 cap = curses.tigetstr(cap_name) or ''
138 return re.sub(r'\$<\d+>[/*]?', '', cap)
139
141 """
142 Replace each $-substitutions in the given template string with
143 the corresponding terminal control string (if it's defined) or
144 '' (if it's not).
145 """
146 return re.sub(r'\$\$|\${\w+}', self._render_sub, template)
147
149 s = match.group()
150 if s == '$$': return s
151 else: return getattr(self, s[2:-1])
152
153
154
155
156
158 """
159 A 3-line progress bar, which looks like::
160
161 Header
162 20% [===========----------------------------------]
163 progress message
164
165 The progress bar is colored, if the terminal supports color
166 output; and adjusts to the width of the terminal.
167 """
168 BAR = '%3d%% ${GREEN}[${BOLD}%s%s${NORMAL}${GREEN}]${NORMAL}\n'
169 HEADER = '${BOLD}${CYAN}%s${NORMAL}\n\n'
170
172 self.term = term
173 if not (self.term.CLEAR_EOL and self.term.UP and self.term.BOL):
174 raise ValueError("Terminal isn't capable enough -- you "
175 "should use a simpler progress dispaly.")
176 self.width = self.term.COLS or 75
177 self.bar = term.render(self.BAR)
178 self.header = self.term.render(self.HEADER % header.center(self.width))
179 self.cleared = 1
180 self.update(0, '')
181
182 - def update(self, percent, message):
183 if self.cleared:
184 sys.stdout.write(self.header)
185 self.cleared = 0
186 n = int((self.width-10)*percent)
187 sys.stdout.write(
188 self.term.BOL + self.term.UP + self.term.CLEAR_EOL +
189 (self.bar % (100*percent, '='*n, '-'*(self.width-10-n))) +
190 self.term.CLEAR_EOL + message.center(self.width))
191
198
199 if __name__ == '__main__':
200 term = TerminalController()
201 print term.render('${BOLD}${RED}Error:${NORMAL}'), 'paper is ripped'
202