1 files changed, 148 insertions, 0 deletions
diff --git a/src/conf_mode/task_scheduler.py b/src/conf_mode/task_scheduler.py
new file mode 100755
index 000000000..c19b88007
--- /dev/null
+++ b/src/conf_mode/task_scheduler.py
@@ -0,0 +1,148 @@
+#!/usr/bin/env python3
+#
+# Copyright (C) 2017 VyOS maintainers and contributors
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License version 2 or later as
+# published by the Free Software Foundation.
+#
+# 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 os
+import re
+import sys
+
+from vyos.config import Config
+from vyos import ConfigError
+
+
+crontab_file = "/etc/cron.d/vyos-crontab"
+
+
+def format_task(minute="*", hour="*", day="*", dayofweek="*", month="*", user="root", rawspec=None, command=""):
+    fmt_full = "{minute} {hour} {day} {month} {dayofweek} {user} {command}\n"
+    fmt_raw = "{spec} {user} {command}\n"
+
+    if rawspec is None:
+        s = fmt_full.format(minute=minute, hour=hour, day=day,
+                            dayofweek=dayofweek, month=month, command=command, user=user)
+    else:
+        s = fmt_raw.format(spec=rawspec, user=user, command=command)
+
+    return s
+
+def split_interval(s):
+    result = re.search(r"(\d+)([mdh]?)", s)
+    value = int(result.group(1))
+    suffix = result.group(2)
+    return( (value, suffix) )
+
+def make_command(executable, arguments):
+    if arguments:
+        return("{0} {1}".format(executable, arguments))
+    else:
+        return(executable)
+
+def get_config():
+    conf = Config()
+    conf.set_level("system task-scheduler task")
+    task_names = conf.list_nodes("")
+    tasks = []
+
+    for name in task_names:
+        interval = conf.return_value("{0} interval".format(name))
+        spec = conf.return_value("{0} crontab-spec".format(name))
+        executable = conf.return_value("{0} executable path".format(name))
+        args = conf.return_value("{0} executable arguments".format(name))
+        task = {
+                "name": name,
+                "interval": interval,
+                "spec": spec,
+                "executable": executable,
+                "args": args
+              }
+        tasks.append(task)
+
+    return tasks
+
+def verify(tasks):
+    for task in tasks:
+        if not task["interval"] and not task["spec"]:
+            raise ConfigError("Invalid task {0}: must define either interval or crontab-spec".format(task["name"]))
+
+        if task["interval"]:
+            if task["spec"]:
+                raise ConfigError("Invalid task {0}: cannot use interval and crontab-spec at the same time".format(task["name"]))
+ 
+            if not re.match(r"^\d+[mdh]?$", task["interval"]):
+                raise(ConfigError("Invalid interval {0} in task {1}: interval should be a number optionally followed by m, h, or d".format(task["name"], task["interval"])))
+            else:
+                # Check if values are within allowed range
+                value, suffix = split_interval(task["interval"])
+
+                if not suffix or suffix == "m":
+                    if value > 60:
+                        raise ConfigError("Invalid task {0}: interval in minutes must not exceed 60".format(task["name"]))
+                elif suffix == "h":
+                    if value > 24:
+                        raise ConfigError("Invalid task {0}: interval in hours must not exceed 24".format(task["name"]))
+                elif suffix == "d":
+                    if value > 31:
+                        raise ConfigError("Invalid task {0}: interval in days must not exceed 31".format(task["name"]))
+
+        if not task["executable"]:
+            raise ConfigError("Invalid task {0}: executable is not defined".format(task["name"]))
+        else:
+            # Check if executable exists and is executable
+            if not (os.path.isfile(task["executable"]) and os.access(task["executable"], os.X_OK)):
+                raise ConfigError("Invalid task {0}: file {1} does not exist or is not executable".format(task["name"], task["executable"]))
+
+def generate(tasks):
+    crontab_header = "### Generated by vyos-update-crontab.py ###\n"
+    if len(tasks) == 0:
+        if os.path.exists(crontab_file):
+            os.remove(crontab_file)
+        else:
+            pass
+    else:
+        crontab_lines = []
+        for task in tasks:
+            command = make_command(task["executable"], task["args"])
+            if task["spec"]:
+                line = format_task(command=command, rawspec=task["spec"])
+            else:
+                value, suffix = split_interval(task["interval"])
+                if not suffix or suffix == "m":
+                    line = format_task(command=command, minute="*/{0}".format(value))
+                elif suffix == "h":
+                    line = format_task(command=command, minute="0", hour="*/{0}".format(value))
+                elif suffix == "d":
+                    line = format_task(command=command, minute="0", hour="0", day="*/{0}".format(value))
+            crontab_lines.append(line)
+
+        with open(crontab_file, 'w') as f:
+            f.write(crontab_header)
+            f.writelines(crontab_lines)
+
+def apply(config):
+    # No daemon restarts etc. needed for cron
+    pass
+
+
+if __name__ == '__main__':
+    try:
+        c = get_config()
+        verify(c)
+        generate(c)
+        apply(c)
+    except ConfigError as e:
+        print(e)
+        sys.exit(1)