[feature] add nrmd-wide support for singularity

The daemon can be configured to launch singularity containers. In such
case, the manifest must contain an image section.

Note that this doesn't support any resource management with singularity,
since that stuff is only available as root. We will add a second
container runtime option to support it later.

bin/nrmd

@@ -45,6 +45,8 @@ def main(argv=None):
                 "argo_perf_wrapper": "nrm-perfwrapper",
                 "argo_nodeos_config": "argo_nodeos_config",
                 "pmpi_lib": "/usr/lib/libnrm-pmpi.so",
+                "singularity": "singularity",
+                "container_runtime": "nodeos",
                 }
 
     if args.print_defaults:
@@ -101,6 +103,20 @@ def main(argv=None):
                  "environment variable.",
             default=os.environ.get('ARGO_PERF_WRAPPER',
                                    'nrm-perfwrapper'))
+    parser.add_argument(
+            '--singularity',
+            help="Path to the singularity command. "
+                 "Override default with the SINGULARITY environment variable.",
+            default=os.environ.get('SINGULARITY', defaults['singularity']))
+    parser.add_argument(
+            '--container-runtime',
+            help="Choice of container runtime. "
+                 "Override default with the ARGO_CONTAINER_RUNTIME "
+                 "environment variable.",
+            choices=['nodeos', 'singularity'],
+            default=os.environ.get('ARGO_CONTAINER_RUNTIME',
+                                   defaults['container_runtime']))
+
     args = parser.parse_args(remaining_argv)
     nrm.daemon.runner(config=args)
     return(0)

nrm/aci.py

@@ -321,6 +321,29 @@ class App(SpecField):
         return super(App, self).load(data)
 
 
+class Image(SpecField):
+
+    """Information on the container image to use."""
+
+    fields = {"path": spec(unicode, True),
+              "type": spec(unicode, True),
+              }
+
+    def __init__(self):
+        """Create an empty image."""
+        pass
+
+    def load(self, data):
+        """Load from json dict."""
+        ret = super(Image, self).load(data)
+        if not ret:
+            return ret
+        if self.type not in ['sif', 'docker']:
+            logger.error("Image type not recognized")
+            return False
+        return True
+
+
 class ImageManifest(SpecField):
 
     """Represent an ACI Image Manifest."""
@@ -329,6 +352,7 @@ class ImageManifest(SpecField):
               "acVersion": spec(unicode, True),
               "name": spec(unicode, True),
               "app": spec(App, True),
+              "image": spec(Image, False),
               }
 
     def __init__(self):

nrm/containers.py

@@ -13,7 +13,7 @@ from __future__ import print_function
 from aci import ImageManifest
 from collections import namedtuple
 import logging
-from subprograms import ChrtClient, NodeOSClient, resources
+from subprograms import ChrtClient, NodeOSClient, resources, SingularityClient
 import operator
 
 logger = logging.getLogger('nrm')
@@ -250,6 +250,55 @@ class NodeOSRuntime(ContainerRuntime):
         self.client.delete(container_uuid, kill)
 
 
+class SingularityRootRuntime(ContainerRuntime):
+
+    """Implements the container runtime interface using the singularity
+    subprogram."""
+
+    def __init__(self, path="argo_singularity_config"):
+        """Creates the client for singularity, with an optional custom
+        path/command."""
+        self.client = SingularityClient(argo_singularity_config=path)
+
+    def create(self, container):
+        """Uses the container resource allocation to create a container."""
+        self.client.oci_start(container.uuid, container.resources)
+
+    def execute(self, container_uuid, args, environ):
+        """Launches a command in the container."""
+        return self.client.oci_execute(container_uuid, args, environ)
+
+    def delete(self, container_uuid, kill=False):
+        """Delete the container."""
+        self.client.oci_delete(container_uuid, kill)
+
+
+class SingularityUserRuntime(ContainerRuntime):
+
+    """Implements the container runtime interface using the singularity
+    subprogram."""
+
+    def __init__(self, path="singularity"):
+        """Creates the client for singularity, with an optional custom
+        path/command."""
+        self.client = SingularityClient(singularity_path=path)
+        self.containers = dict()
+
+    def create(self, container):
+        """Uses the container resource allocation to create a container."""
+        self.containers[container.uuid] = container
+
+    def execute(self, container_uuid, args, environ):
+        """Launches a command in the container."""
+        imageinfo = self.containers[container_uuid].manifest.image
+        # not checking image because singularity supports all types
+        return self.client.execute(imageinfo.path, args, environ)
+
+    def delete(self, container_uuid, kill=False):
+        """Delete the container."""
+        del self.containers[container_uuid]
+
+
 class DummyRuntime(ContainerRuntime):
 
     """Implements a dummy runtime that doesn't create any container, but still

nrm/daemon.py

@@ -11,7 +11,7 @@
 from __future__ import print_function
 
 from applications import ApplicationManager
-from containers import ContainerManager, NodeOSRuntime
+from containers import ContainerManager, NodeOSRuntime, SingularityUserRuntime
 from controller import Controller, PowerActuator
 from powerpolicy import PowerPolicyManager
 from functools import partial
@@ -307,8 +307,14 @@ class Daemon(object):
 
         # create managers
         self.resource_manager = ResourceManager(hwloc=self.config.hwloc)
-        container_runtime = \
-            NodeOSRuntime(self.config.argo_nodeos_config)
+        container_runtime = None
+        if self.config.container_runtime == 'nodeos':
+            container_runtime = \
+                NodeOSRuntime(path=self.config.argo_nodeos_config)
+        elif self.config.container_runtime == 'singularity':
+            container_runtime = \
+                SingularityUserRuntime(self.config.singularity)
+        assert(container_runtime is not None)
         self.container_manager = ContainerManager(
                 container_runtime,
                 self.resource_manager,

nrm/subprograms.py

@@ -141,6 +141,28 @@ class NodeOSClient(object):
                                   cwd=environ['PWD'])
 
 
+class SingularityClient(object):
+
+    """Client to singularity."""
+
+    def __init__(self, singularity_path="singularity"):
+        """Load client configuration."""
+        self.prefix = singularity_path
+
+    def execute(self, container_image, argv, environ):
+        """Execute argv inside container.
+
+        singularity exec --bind ... container.sif <command>"""
+        args = [self.prefix]  # singularity
+        args.extend(['exec', '--bind', '/tmp/nrm-downstream-event',
+                     container_image])
+        args.extend(argv)
+        return process.Subprocess(args, env=environ,
+                                  stdout=process.Subprocess.STREAM,
+                                  stderr=process.Subprocess.STREAM,
+                                  close_fds=True)
+
+
 class ChrtClient(object):
 
     """Client to chrt command line wrapper."""