adding logs command

Signed-off-by: Vanessa Sochat <[email protected]>

Author: vsoch

scompose/client/__init__.py

@@ -110,17 +110,23 @@ def get_parser():
     kill = subparsers.add_parser("kill",
                                  help="kill instances")
 
+    # Logs
+
     logs = subparsers.add_parser("logs",
                                  help="view output from instances")
 
+    logs.add_argument("--tail", default=0, 
+                      dest='tail', type=int,
+                      help='clip logs to certain number of lines from end')
+
     ps = subparsers.add_parser("ps",
                                help="list instances")
 
     restart = subparsers.add_parser("restart",
                                      help="stop and start containers.")
 
     # Add list of names
-    for sub in [create, down, up]:
+    for sub in [create, down, logs, up]:
         sub.add_argument('names', nargs="*",
                           help='the names of the instances to target')
 

scompose/client/logs.py

@@ -0,0 +1,38 @@
+'''
+
+Copyright (C) 2019 Vanessa Sochat.
+
+This program is free software: you can redistribute it and/or modify it
+under the terms of the GNU Affero 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 Affero General Public
+License for more details.
+
+You should have received a copy of the GNU Affero General Public License
+along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+'''
+
+from scompose.project import Project
+import logging
+import json
+import sys
+import os
+
+
+log = logging.getLogger(__name__)
+
+def main(args, parser, extra):
+    '''bring one or more instances down
+    '''
+    # Initialize the project
+    project = Project(filename=args.file,
+                      name=args.project_name,
+                      env_file=args.env_file)
+
+    # Create instances, and if none specified, create all
+    project.logs(args.names, args.tail)

scompose/project/instance.py

@@ -18,9 +18,11 @@
 '''
 
 from scompose.logger import bot
+from scompose.utils import get_userhome
 from spython.main import get_client
 import shlex as _shlex
 import os
+import platform
 import sys
 
 
@@ -278,6 +280,46 @@ def stop(self):
             self.instance.stop(sudo=self.sudo)
             self.instance = None
 
+# Logs
+
+    def logs(self, tail=0):
+        '''show logs for an instance'''
+
+        home = get_userhome()
+        user = os.path.basename(home)
+
+        if self.sudo:
+            home = '/root'
+            user = "root"
+
+        # Hostname
+        hostname = platform.node()
+
+        log_folder = os.path.join(home, '.singularity', 'instances', 'logs', hostname, user)
+
+        for ext in ['OUT', 'ERR']:
+            logfile = os.path.join(log_folder, '%s.%s' % (self.name, ext.lower()))
+
+            # Use Try/catch to account for not existing.
+            try:
+                if not self.sudo:
+                    result = self.client._run_command(['cat', logfile], quiet=True)
+                else:
+                    result = self.client._run_command(['sudo', 'cat', logfile], quiet=True)
+
+                if result:
+ 
+                    # If the user only wants to see certain number
+                    if tail > 0:
+                        result = '\n'.join(result.split('\n')[-tail:])
+                    bot.custom(prefix=self.name, message=ext, color='CYAN')
+                    print(result)
+                    bot.newline()
+
+            except:
+                pass
+
+
 # Create and Delete
 
     def up(self, working_dir, sudo=False, writable_tmpfs=False):

scompose/project/project.py

@@ -165,13 +165,13 @@ def parse(self):
 
 # Networking
 
-
     def create_hosts(self, name, depends_on):
         '''create a hosts file to bind to all containers, where we define the
            correct hostnames to correspond with the ip addresses created.
 
            Note: This function is terrible. Singularity should easily expose 
-                 these addresses.
+                 these addresses. See issue here:
+                 https://github.com/sylabs/singularity/issues/3751
         '''
         template = read_file(get_template('hosts'))
         hosts_file = os.path.join(self.working_dir, 'etc.hosts.%s' % name)
@@ -184,6 +184,7 @@ def create_hosts(self, name, depends_on):
                        result = self.client.execute(image=instance.instance.get_uri(), 
                                                     command=['hostname', '-I'],
                                                     return_result=True,
+                                                    quiet=True,
                                                     sudo=self.sudo)
 
                        # Busybox won't have hostname -I
@@ -192,6 +193,7 @@ def create_hosts(self, name, depends_on):
                            result = self.client.execute(image=instance.instance.get_uri(), 
                                                         command=cmd,
                                                         return_result=True,
+                                                        quiet=True,
                                                         sudo=self.sudo)
 
                        ip_address = result['message'].strip('\n').strip()
@@ -218,6 +220,19 @@ def shell(self, name):
                 if instance.exists():
                     self.client.shell(instance.instance.get_uri())
 
+
+    def logs(self, names, tail=0):
+        '''logs will print logs to the screen.
+        '''
+        # If no names provided, show all logs
+        if not names:
+            names = self.get_instance_names()
+
+        # Print logs for each
+        for name in names:
+            if name in self.instances:
+                self.instances[name].logs(tail=tail)
+
 # Config
 
     def view_config(self):

scompose/utils/__init__.py

@@ -40,6 +40,12 @@ def get_installdir():
     return os.path.abspath(os.path.dirname(os.path.dirname(__file__)))
 
 
+def get_userhome():
+    '''get the user home based on the effective uid
+    '''
+    return pwd.getpwuid(os.getuid())[5]
+
+
 def run_command(cmd, sudo=False):
     '''run_command uses subprocess to send a command to the terminal.