self._pid = None
self._ppid = None
self._home = "app-%s" % self.guid
+ self._in_foreground = False
# keep a reference to the running process handler when
# the command is not executed as remote daemon in background
@property
def in_foreground(self):
- """ Returns True is the command needs to be executed in foreground.
+ """ Returns True if the command needs to be executed in foreground.
This means that command will be executed using 'execute' instead of
- 'run'.
-
+ 'run' ('run' executes a command in background and detached from the
+ terminal)
+
When using X11 forwarding option, the command can not run in background
- and detached from a terminal in the remote host, since we need to keep
- the SSH connection to receive graphical data
+ and detached from a terminal, since we need to keep the terminal attached
+ to interact with it.
"""
- return self.get("forwardX11") or False
+ return self.get("forwardX11") or self._in_foreground
def trace(self, name, attr = TraceAttr.ALL, block = 512, offset = 0):
self.info("Retrieving '%s' trace %s " % (name, attr))
if stdin:
# create dir for sources
self.info(" Uploading stdin ")
-
+
dst = os.path.join(self.app_home, "stdin")
+
+ # TODO:
+ # Check wether file already exists and if it exists
+ # wether the file we want to upload is the same
+ # (using md5sum)
+
self.node.upload(stdin, dst, text = True)
def install_dependencies(self):
def start(self):
command = self.get("command")
- env = self.get("env")
- stdin = "stdin" if self.get("stdin") else None
- stdout = "stdout" if self.get("stdout") else "stdout"
- stderr = "stderr" if self.get("stderr") else "stderr"
- sudo = self.get("sudo") or False
- failed = False
self.info("Starting command '%s'" % command)
- if self.in_foreground:
- # If command should be ran in foreground, we invoke
- # the node 'execute' method
- if not command:
- msg = "No command is defined but X11 forwarding has been set"
- self.error(msg)
- self._state = ResourceState.FAILED
- raise RuntimeError, msg
+ if not command:
+ # If no command was given (i.e. Application was used for dependency
+ # installation), then the application is directly marked as FINISHED
+ self._state = ResourceState.FINISHED
+ else:
- # Export environment
- environ = "\n".join(map(lambda e: "export %s" % e, env.split(" ")))\
- if env else ""
+ if self.in_foreground:
+ self._start_in_foreground()
+ else:
+ self._start_in_background()
- command = environ + command
- command = self.replace_paths(command)
-
- x11 = self.get("forwardX11")
-
- # We save the reference to the process in self._proc
- # to be able to kill the process from the stop method
- (out, err), self._proc = self.node.execute(command,
- sudo = sudo,
- stdin = stdin,
- forward_x11 = x11,
- blocking = False)
-
- if self._proc.poll():
- out = ""
- err = self._proc.stderr.read()
- self._state = ResourceState.FAILED
- self.error(msg, out, err)
- raise RuntimeError, msg
-
super(LinuxApplication, self).start()
- elif command:
- # If command is set (i.e. application not used only for dependency
- # installation), and it does not need to run in foreground, we use
- # the 'run' method of the node to launch the application as a daemon
-
- # The real command to execute was previously uploaded to a remote bash
- # script during deployment, now run the remote script using 'run' method
- # from the node
- cmd = "bash ./app.sh"
- (out, err), proc = self.node.run(cmd, self.app_home,
- stdin = stdin,
- stdout = stdout,
- stderr = stderr,
- sudo = sudo)
-
- # check if execution errors occurred
- msg = " Failed to start command '%s' " % command
-
- if proc.poll() and err:
- self.error(msg, out, err)
- raise RuntimeError, msg
-
- # Check status of process running in background
- pid, ppid = self.node.wait_pid(self.app_home)
- if pid: self._pid = int(pid)
- if ppid: self._ppid = int(ppid)
-
- # If the process is not running, check for error information
- # on the remote machine
- if not self.pid or not self.ppid:
- (out, err), proc = self.node.check_output(self.app_home, 'stderr')
- self.error(msg, out, err)
+ def _start_in_foreground(self):
+ command = self.get("command")
+ stdin = "stdin" if self.get("stdin") else None
+ sudo = self.get("sudo") or False
+ x11 = self.get("forwardX11")
- msg2 = " Setting state to Failed"
- self.debug(msg2)
- self._state = ResourceState.FAILED
+ # Command will be launched in foreground and attached to the
+ # terminal using the node 'execute' in non blocking mode.
- raise RuntimeError, msg
-
- super(LinuxApplication, self).start()
+ # Export environment
+ env = self.get("env")
+ environ = self.node.format_environment(env, inline = True)
+ command = environ + command
+ command = self.replace_paths(command)
+
+ # We save the reference to the process in self._proc
+ # to be able to kill the process from the stop method.
+ # We also set blocking = False, since we don't want the
+ # thread to block until the execution finishes.
+ (out, err), self._proc = self.node.execute(command,
+ sudo = sudo,
+ stdin = stdin,
+ forward_x11 = x11,
+ blocking = False)
+
+ if self._proc.poll():
+ self._state = ResourceState.FAILED
+ self.error(msg, out, err)
+ raise RuntimeError, msg
- else:
- # If no command was given (i.e. Application was used for dependency
- # installation), then the application is directly marked as FINISHED
- self._state = ResourceState.FINISHED
-
+ def _start_in_background(self):
+ command = self.get("command")
+ env = self.get("env")
+ stdin = "stdin" if self.get("stdin") else None
+ stdout = "stdout" if self.get("stdout") else "stdout"
+ stderr = "stderr" if self.get("stderr") else "stderr"
+ sudo = self.get("sudo") or False
+
+ # Command will be as a daemon in baground and detached from any terminal.
+ # The real command to run was previously uploaded to a bash script
+ # during deployment, now launch the remote script using 'run'
+ # method from the node
+ cmd = "bash ./app.sh"
+ (out, err), proc = self.node.run(cmd, self.app_home,
+ stdin = stdin,
+ stdout = stdout,
+ stderr = stderr,
+ sudo = sudo)
+
+ # check if execution errors occurred
+ msg = " Failed to start command '%s' " % command
+
+ if proc.poll():
+ self._state = ResourceState.FAILED
+ self.error(msg, out, err)
+ raise RuntimeError, msg
+
+ # Wait for pid file to be generated
+ pid, ppid = self.node.wait_pid(self.app_home)
+ if pid: self._pid = int(pid)
+ if ppid: self._ppid = int(ppid)
+
+ # If the process is not running, check for error information
+ # on the remote machine
+ if not self.pid or not self.ppid:
+ (out, err), proc = self.node.check_errors(self.app_home,
+ stderr = stderr)
+
+ # Out is what was written in the stderr file
+ if err:
+ self._state = ResourceState.FAILED
+ msg = " Failed to start command '%s' " % command
+ self.error(msg, out, err)
+ raise RuntimeError, msg
+
def stop(self):
""" Stops application execution
"""
command = self.get('command') or ''
- state = self.state
- if state == ResourceState.STARTED:
+ if self.state == ResourceState.STARTED:
stopped = True
self.info("Stopping command '%s'" % command)
if self._proc:
self._proc.kill()
else:
- (out, err), proc = self.node.kill(self.pid, self.ppid)
+ # Only try to kill the process if the pid and ppid
+ # were retrieved
+ if self.pid and self.ppid:
+ (out, err), proc = self.node.kill(self.pid, self.ppid)
- if out or err:
- # check if execution errors occurred
- msg = " Failed to STOP command '%s' " % self.get("command")
- self.error(msg, out, err)
- self._state = ResourceState.FAILED
- stopped = False
+ if out or err:
+ # check if execution errors occurred
+ msg = " Failed to STOP command '%s' " % self.get("command")
+ self.error(msg, out, err)
+ self._state = ResourceState.FAILED
+ stopped = False
if stopped:
super(LinuxApplication, self).stop()
self.node.execute(tear_down)
self.stop()
+
if self.state == ResourceState.STOPPED:
super(LinuxApplication, self).release()
@property
def state(self):
+ """ Returns the state of the application
+ """
if self._state == ResourceState.STARTED:
if self.in_foreground:
+ # Check if the process we used to execute the command
+ # is still running ...
retcode = self._proc.poll()
-
+
# retcode == None -> running
# retcode > 0 -> error
# retcode == 0 -> finished
if retcode:
out = ""
+ msg = " Failed to execute command '%s'" % self.get("command")
err = self._proc.stderr.read()
- self._state = ResourceState.FAILED
self.error(msg, out, err)
+ self._state = ResourceState.FAILED
elif retcode == 0:
self._state = ResourceState.FINISHED
else:
- # To avoid overwhelming the remote hosts and the local processor
- # with too many ssh queries, the state is only requested
- # every 'state_check_delay' seconds.
+ # We need to query the status of the command we launched in
+ # background. In oredr to avoid overwhelming the remote host and
+ # the local processor with too many ssh queries, the state is only
+ # requested every 'state_check_delay' seconds.
state_check_delay = 0.5
if strfdiff(strfnow(), self._last_state_check) > state_check_delay:
# check if execution errors occurred
(out, err), proc = self.node.check_errors(self.app_home)
- if out or err:
- if err.find("No such file or directory") >= 0 :
- # The resource is marked as started, but the
- # command was not yet executed
- return ResourceState.READY
-
+ if err:
msg = " Failed to execute command '%s'" % self.get("command")
self.error(msg, out, err)
self._state = ResourceState.FAILED
elif self.pid and self.ppid:
+ # No execution errors occurred. Make sure the background
+ # process with the recorded pid is still running.
status = self.node.status(self.pid, self.ppid)
if status == ProcStatus.FINISHED: