Merge pull request #14 from davidlmorton/devserver

Added generic devserver package with run() function

ptero_common/devserver.py

@@ -0,0 +1,100 @@
+import errno
+import os
+import sys
+import psutil
+import signal
+import time
+
+honcho_process = None
+children = set()
+
+
+# This is from a stackoverflow answer:
+# http://stackoverflow.com/questions/600268/mkdir-p-functionality-in-python
+def mkdir_p(path):
+    try:
+        os.makedirs(path)
+    except OSError as exc: # Python >2.5
+        if exc.errno == errno.EEXIST and os.path.isdir(path):
+            pass
+        else:
+            raise
+
+
+def service_command_line(procfile_path, workers):
+    return ['honcho', 'start', '-f', procfile_path,
+            '-c', ] + ["%s=%d" % (key, value) for key, value in workers.items()]
+
+
+def shutdown():
+    if signal_processes(children, signal.SIGINT):
+        time.sleep(3)
+        signal_processes(children, signal.SIGKILL)
+
+def signal_processes(processes, sig):
+    signaled = []
+    for p in processes:
+        try:
+            p.send_signal(sig)
+            signaled.append(p.pid)
+        except psutil.NoSuchProcess:
+            pass
+
+    if len(signaled) > 0:
+        sys.stderr.write(
+            "Sent signal (%s) to processes: %s\n" % (sig, signaled))
+        return True
+    else:
+        return False
+
+def expand_children():
+    for process in children:
+        try:
+            children.update(process.get_children(recursive=True))
+        except psutil.NoSuchProcess:
+            pass
+
+
+def cleanup(*args, **kwargs):
+    expand_children()
+    try:
+        honcho_process.send_signal(signal.SIGINT)
+    except psutil.NoSuchProcess:
+        return
+
+    try:
+        honcho_process.wait(timeout=3)
+    except psutil.TimeoutExpired:
+        pass
+
+    shutdown()
+
+
+def setup_signal_handlers():
+    signal.signal(signal.SIGINT, cleanup)
+    signal.signal(signal.SIGTERM, cleanup)
+
+
+def run(logdir, procfile_path, workers):
+    global honcho_process
+
+    setup_signal_handlers()
+
+    if (logdir == '-'):
+        outlog = sys.stdout
+        errlog = sys.stderr
+    else:
+        mkdir_p(logdir)
+        sys.stderr.write('Starting up devserver... logging to: %s' % logdir)
+        outlog = open(os.path.join(logdir, 'honcho.out'), 'w')
+        errlog = open(os.path.join(logdir, 'honcho.err'), 'w')
+
+    honcho_process = psutil.Popen(
+        service_command_line(procfile_path, workers), shell=False,
+        stdout=outlog, stderr=errlog)
+    time.sleep(3)
+    sys.stderr.write('devserver is now up...')
+    children.update(psutil.Process().get_children(recursive=True))
+
+    honcho_process.wait()
+    cleanup()