Wrote module for showing progress and messages to terminal users.

2 files changed, 89 insertions, 0 deletions

diff --git a/obnamlib/status.py b/obnamlib/status.py
new file mode 100644
index 00000000..f0bbb0dc
--- /dev/null
+++ b/obnamlib/status.py
@@ -0,0 +1,88 @@
+# Copyright (C) 2009  Lars Wirzenius
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+
+import sys
+import time
+
+
+class Status(object):
+
+    '''Base class for informing user of current status of application.'''
+    
+    def progress(self, percent, message):
+        '''Show user that some progress is happening.'''
+        
+    def notify(self, message):
+        '''Notify user about something by displaying a message.'''
+
+    def finished(self):
+        '''No more status updates are needed.'''
+
+
+class TerminalStatus(object):
+
+    '''Update status to terminal.'''
+    
+    def __init__(self):
+        self.written = ''
+        self.when = 0
+        self.freq = 1.0
+        self.width = 79 # FIXME: Should query terminal and react to SIGWINCH
+
+    def raw_write(self, msg):
+        if sys.stdout.isatty():
+            sys.stdout.write('\b \b' * len(self.written))
+            sys.stdout.write(msg)
+            sys.stdout.flush()
+    
+    def write(self, msg, force=False):
+        msg = msg[:self.width]
+        if force:
+            self.raw_write(msg)
+        else:
+            now = time.time()
+            if now - self.when >= self.freq:
+                self.raw_write(msg)
+                self.when = now
+        self.written = msg
+
+    def clear(self):
+        self.write('', force=True)
+
+    def progress(self, percent, message):
+        self.write('%.1f %% %s' % (float(percent), message))
+
+    def notify(self, message):
+        written = self.written
+        self.clear()
+        sys.stdout.write('%s\n' % message)
+        sys.stdout.flush()
+        self.write(written, force=True)
+
+    def finished(self):
+        self.write(self.written, force=True)
+        sys.stdout.write('\n')
+        sys.stdout.flush()
+
+
+if __name__ == '__main__':
+    ts = TerminalStatus()
+    for pc in range(0, 100, 10):
+        ts.progress(pc, 'yo!')
+        time.sleep(1)
+        ts.notify('hmm...')
+    ts.finished()
+
diff --git a/without-tests b/without-tests
index eea0bcf1..af7fc51f 100644
--- a/without-tests
+++ b/without-tests
@@ -1 +1,2 @@
 ./obnamlib/__init__.py
+./obnamlib/status.py