Support docker image as function code

Allow user to create function using her own docker image including
all the code and dependencies inside. The image needs to have an
script running as entry point, expecting user's input as params.

This allow users to execute functions written in any language.

qinling/api/controllers/v1/function.py

@@ -29,6 +29,7 @@ from qinling.api.controllers.v1 import types
 from qinling import context
 from qinling.db import api as db_api
 from qinling import exceptions as exc
+from qinling import rpc
 from qinling.storage import base as storage_base
 from qinling.utils.openstack import swift as swift_util
 from qinling.utils import rest_utils
@@ -36,13 +37,14 @@ from qinling.utils import rest_utils
 LOG = logging.getLogger(__name__)
 CONF = cfg.CONF
 
-POST_REQUIRED = set(['name', 'runtime_id', 'code'])
+POST_REQUIRED = set(['name', 'code'])
 CODE_SOURCE = set(['package', 'swift', 'image'])
 
 
 class FunctionsController(rest.RestController):
     def __init__(self, *args, **kwargs):
         self.storage_provider = storage_base.load_storage_provider(CONF)
+        self.engine_client = rpc.get_engine_client()
 
         super(FunctionsController, self).__init__(*args, **kwargs)
 
@@ -69,6 +71,13 @@ class FunctionsController(rest.RestController):
                 container = func_db.code['swift']['container']
                 obj = func_db.code['swift']['object']
                 f = swift_util.download_object(container, obj)
+            else:
+                msg = 'Download image function is not allowed.'
+                pecan.abort(
+                    status_code=405,
+                    detail=msg,
+                    headers={'Server-Error-Message': msg}
+                )
 
             pecan.response.app_iter = (f if isinstance(f, collections.Iterable)
                                        else FileIter(f))
@@ -82,21 +91,17 @@ class FunctionsController(rest.RestController):
     def post(self, **kwargs):
         LOG.info("Creating function, params=%s", kwargs)
 
+        # When using image to create function, runtime_id is not a required
+        # param.
         if not POST_REQUIRED.issubset(set(kwargs.keys())):
             raise exc.InputException(
                 'Required param is missing. Required: %s' % POST_REQUIRED
             )
 
-        runtime = db_api.get_runtime(kwargs['runtime_id'])
-        if runtime.status != 'available':
-            raise exc.InputException(
-                'Runtime %s not available.' % kwargs['runtime_id']
-            )
-
         values = {
             'name': kwargs['name'],
-            'description': kwargs.get('description', None),
-            'runtime_id': kwargs['runtime_id'],
+            'description': kwargs.get('description'),
+            'runtime_id': kwargs.get('runtime_id'),
             'code': json.loads(kwargs['code']),
             'entry': kwargs.get('entry', 'main'),
         }
@@ -105,9 +110,19 @@ class FunctionsController(rest.RestController):
         if not source or source not in CODE_SOURCE:
             raise exc.InputException(
                 'Invalid code source specified, available sources: %s' %
-                CODE_SOURCE
+                ', '.join(CODE_SOURCE)
             )
 
+        if source != 'image':
+            if not kwargs.get('runtime_id'):
+                raise exc.InputException('"runtime_id" must be specified.')
+
+            runtime = db_api.get_runtime(kwargs['runtime_id'])
+            if runtime.status != 'available':
+                raise exc.InputException(
+                    'Runtime %s is not available.' % kwargs['runtime_id']
+                )
+
         store = False
         if values['code']['source'] == 'package':
             store = True
@@ -124,12 +139,12 @@ class FunctionsController(rest.RestController):
             if not swift_util.check_object(container, object):
                 raise exc.InputException('Object does not exist in Swift.')
 
-        ctx = context.get_ctx()
-
         with db_api.transaction():
             func_db = db_api.create_function(values)
 
             if store:
+                ctx = context.get_ctx()
+
                 self.storage_provider.store(
                     ctx.projectid,
                     func_db.id,
@@ -161,6 +176,8 @@ class FunctionsController(rest.RestController):
 
             if source == 'package':
                 self.storage_provider.delete(context.get_ctx().projectid, id)
+            if source == 'image':
+                self.engine_client.delete_function(id, func_db.name)
 
             # This will also delete function service mapping as well.
             db_api.delete_function(id)

qinling/db/sqlalchemy/migration/alembic_migrations/versions/001_pike.py

@@ -52,7 +52,7 @@ def upgrade():
         sa.Column('id', sa.String(length=36), nullable=False),
         sa.Column('name', sa.String(length=255), nullable=True),
         sa.Column('description', sa.String(length=255), nullable=True),
-        sa.Column('runtime_id', sa.String(length=36), nullable=False),
+        sa.Column('runtime_id', sa.String(length=36), nullable=True),
         sa.Column('memory_size', sa.Integer, nullable=True),
         sa.Column('timeout', sa.Integer, nullable=True),
         sa.Column('code', st.JsonLongDictType(), nullable=False),

qinling/db/sqlalchemy/models.py

@@ -27,7 +27,7 @@ class Function(model_base.QinlingSecureModelBase):
 
     name = sa.Column(sa.String(255), nullable=False)
     description = sa.Column(sa.String(255))
-    runtime_id = sa.Column(sa.String(36), nullable=False)
+    runtime_id = sa.Column(sa.String(36), nullable=True)
     memory_size = sa.Column(sa.Integer)
     timeout = sa.Column(sa.Integer)
     code = sa.Column(st.JsonLongDictType(), nullable=False)

qinling/engine/default_engine.py

@@ -15,6 +15,7 @@
 from oslo_log import log as logging
 
 from qinling.db import api as db_api
+from qinling.utils import common
 
 LOG = logging.getLogger(__name__)
 
@@ -72,16 +73,42 @@ class DefaultEngine(object):
 
         with db_api.transaction():
             execution = db_api.get_execution(execution_id)
-            runtime = db_api.get_runtime(runtime_id)
-            identifier = '%s-%s' % (runtime_id, runtime.name)
-            labels = {'runtime_name': runtime.name, 'runtime_id': runtime_id}
+            function = db_api.get_function(function_id)
+
+            source = function.code['source']
+            image = None
+            identifier = None
+            labels = None
+
+            if source == 'image':
+                image = function.code['image']
+                identifier = ('%s-%s' %
+                              (common.generate_unicode_uuid(dashed=False),
+                               function_id)
+                              )[:63]
+                labels = {
+                    'function_name': function.name, 'function_id': function_id
+                }
+            else:
+                runtime = db_api.get_runtime(runtime_id)
+                identifier = ('%s-%s' % (runtime_id, runtime.name))[:63]
+                labels = {
+                    'runtime_name': runtime.name, 'runtime_id': runtime_id
+                }
 
             service_url = self.orchestrator.prepare_execution(
-                function_id, identifier=identifier, labels=labels
+                function_id,
+                image=image,
+                identifier=identifier,
+                labels=labels,
+                input=input
             )
 
             output = self.orchestrator.run_execution(
-                function_id, input=input, service_url=service_url
+                function_id,
+                input=input,
+                identifier=identifier,
+                service_url=service_url,
             )
 
             LOG.debug(
@@ -93,8 +120,17 @@ class DefaultEngine(object):
             execution.output = output
             execution.status = 'success'
 
-            mapping = {
-                'function_id': function_id,
-                'service_url': service_url
-            }
-            db_api.create_function_service_mapping(mapping)
+            if not image:
+                mapping = {
+                    'function_id': function_id,
+                    'service_url': service_url
+                }
+                db_api.create_function_service_mapping(mapping)
+
+    def delete_function(self, ctx, function_id, function_name):
+        LOG.info('Start to delete function, id=%s', function_id)
+
+        labels = {
+            'function_name': function_name, 'function_id': function_id
+        }
+        self.orchestrator.delete_function(labels)

qinling/orchestrator/base.py

@@ -42,6 +42,10 @@ class OrchestratorBase(object):
     def run_execution(self, function_id, **kwargs):
         raise NotImplementedError
 
+    @abc.abstractmethod
+    def delete_function(self, labels):
+        raise NotImplementedError
+
 
 def load_orchestrator(conf):
     global ORCHESTRATOR

qinling/orchestrator/kubernetes/manager.py

@@ -53,6 +53,7 @@ class KubernetesManager(base.OrchestratorBase):
 
         self.deployment_template = jinja_env.get_template('deployment.j2')
         self.service_template = jinja_env.get_template('service.j2')
+        self.pod_template = jinja_env.get_template('pod.j2')
 
     def _ensure_namespace(self):
         ret = self.v1.list_namespace()
@@ -249,19 +250,82 @@ class KubernetesManager(base.OrchestratorBase):
 
         return pod_service_url
 
-    def prepare_execution(self, function_id, identifier=None, labels=None):
-        pod = self._choose_available_pod(labels)
+    def _create_pod(self, image, pod_name, labels, input):
+        pod_body = self.pod_template.render(
+            {
+                "pod_name": pod_name,
+                "labels": labels,
+                "pod_image": image,
+                "input": input
+            }
+        )
+
+        LOG.info(
+            "Creating pod %s for image function:\n%s", pod_name, pod_body
+        )
+
+        self.v1.create_namespaced_pod(
+            self.conf.kubernetes.namespace,
+            body=yaml.safe_load(pod_body),
+        )
+
+    def prepare_execution(self, function_id, image=None, identifier=None,
+                          labels=None, input=None):
+        """Prepare service URL for function.
+
+        For image function, create a single pod with input, so the function
+        will be executed.
+
+        For normal function, choose a pod from the pool and expose a service,
+        return the service URL.
+        """
+        pod = None
+
+        if image:
+            self._create_pod(image, identifier, labels, input)
+            return None
+        else:
+            pod = self._choose_available_pod(labels)
 
         if not pod:
             raise exc.OrchestratorException('No pod available.')
 
         return self._prepare_pod(pod, identifier, function_id, labels)
 
-    def run_execution(self, function_id, input=None, service_url=None):
-        func_url = '%s/execute' % service_url
+    def run_execution(self, function_id, input=None, identifier=None,
+                      service_url=None):
+        if service_url:
+            func_url = '%s/execute' % service_url
+            LOG.info('Invoke function %s, url: %s', function_id, func_url)
+
+            r = requests.post(func_url, data=input)
+
+            return {'result': r.json()}
+        else:
+            status = None
+
+            # Wait for execution to be finished.
+            # TODO(kong): Do not retry infinitely.
+            while status != 'Succeeded':
+                pod = self.v1.read_namespaced_pod(
+                    identifier,
+                    self.conf.kubernetes.namespace
+                )
+                status = pod.status.phase
 
-        LOG.info('Invoke function %s, url: %s', function_id, func_url)
+                time.sleep(0.5)
+
+            output = self.v1.read_namespaced_pod_log(
+                identifier,
+                self.conf.kubernetes.namespace,
+            )
 
-        r = requests.post(func_url, data=input)
+            return {'result': output}
 
-        return {'result': r.json()}
+    def delete_function(self, labels):
+        selector = common.convert_dict_to_string(labels)
+
+        self.v1.delete_collection_namespaced_pod(
+            self.conf.kubernetes.namespace,
+            label_selector=selector
+        )

qinling/orchestrator/kubernetes/templates/pod.j2

@@ -0,0 +1,20 @@
+apiVersion: v1
+kind: Pod
+metadata:
+  name: {{ pod_name }}
+  labels:
+  {% for key, value in labels.items() %}
+    {{ key }}: {{ value }}
+  {% endfor %}
+spec:
+  containers:
+    - name: {{ pod_name }}
+      image: {{ pod_image }}
+      imagePullPolicy: IfNotPresent
+      {% if input %}
+      args:
+      {% for item in input %}
+        - {{ item }}
+      {% endfor %}
+      {% endif %}
+  restartPolicy: Never

qinling/rpc.py

@@ -156,3 +156,12 @@ class EngineClient(object):
             runtime_id=runtime_id,
             input=input
         )
+
+    @wrap_messaging_exception
+    def delete_function(self, id, name):
+        return self._client.prepare(topic=self.topic, server=None).cast(
+            ctx.get_ctx(),
+            'delete_function',
+            function_id=id,
+            function_name=name
+        )

qinling/utils/common.py

@@ -23,8 +23,8 @@ def convert_dict_to_string(d):
     return ','.join(temp_list)
 
 
-def generate_unicode_uuid():
-    return uuidutils.generate_uuid()
+def generate_unicode_uuid(dashed=True):
+    return uuidutils.generate_uuid(dashed=dashed)
 
 
 def disable_ssl_warnings(func):

qinling/utils/openstack/keystone.py

@@ -21,8 +21,6 @@ from qinling import context
 
 CONF = cfg.CONF
 
-KS_SESSION = None
-
 
 def _get_user_keystone_session():
     ctx = context.get_ctx()