Allow simple REST API container deployment

* Add verbs to container entrypoint

* Have REST API serve the schema JSON

* Add documentation explaining how to deploy

Co-Authored-By: Shachar Snapiri <shachar.snapiri@toganetworks.com>
Change-Id: I243130a219d3e9e96bf87d39693e600ea4b627a2
Partially-Implements: blueprint add-dragonflow-api

doc/source/docker_install.rst

@@ -83,12 +83,25 @@ these files using e.g.
 
 Running the container without the controller service
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+The docker entrypoint accepts verbs. To start the container without the
+controller service, use the verb `bash`.
+
+.. code-block:: bash
+
+  docker run --name dragonflow --net $DRAGONFLOW_NET_NAME --ip ${DRAGONFLOW_ADDRESS} -i -t dragonflow:latest --dragonflow_address ${DRAGONFLOW_ADDRESS} --db_address ${NODE1}:2379 bash
+
 This enables you to run the container without running the container service.
 This is useful in order to create a standalone node for Dragonflow API,
 separated from the controller node.
 
-* Run the following commands:
+Running a REST API Service
+~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+To start a REST API service, running on HTTP port 8080, use the verb `rest`.
 
 .. code-block:: bash
 
-  docker run --name dragonflow --net $DRAGONFLOW_NET_NAME --ip ${DRAGONFLOW_ADDRESS} -e DF_NO_CONTROLLER=1 -i -t dragonflow:latest --dragonflow_address ${DRAGONFLOW_ADDRESS} --db_address ${NODE1}:2379
+  docker run --name dragonflow --net $DRAGONFLOW_NET_NAME --ip ${DRAGONFLOW_ADDRESS} -i -t dragonflow:latest --dragonflow_address ${DRAGONFLOW_ADDRESS} --db_address ${NODE1}:2379 rest
+
+The schema would be available on `http://$DRAGONFLOW_ADDRESS:8080/schema.json`.

dragonflow/cmd/eventlet/df_rest_service.py

@@ -23,6 +23,9 @@ from dragonflow.db import model_framework as mf
 from dragonflow.db.models import all  # noqa
 
 
+schema_file = None
+
+
 def nbapi_decorator(f):
     # f(nbapi, ...) -> f(...)
     def wrapper(*args, **kwargs):
@@ -111,6 +114,13 @@ def delete(nbapi, model, name, id_):
     bottle.response.status = HTTPStatus.NO_CONTENT.value
 
 
+@bottle.get('/schema.json')
+def schema():
+    if not schema_file:
+        bottle.abort(HTTPStatus.NOT_FOUND.value)
+    return bottle.static_file(schema_file, '/')
+
+
 def main():
     parser = argparse.ArgumentParser(description='Dragonflow REST server')
     parser.add_argument('--host', type=str, default='127.0.0.1',
@@ -121,6 +131,11 @@ def main():
                         default='/etc/dragonflow/dragonflow.ini',
                         help=('Dragonflow config file '
                               '(/etc/dragonflow/dragonflow.ini)'))
+    parser.add_argument('--json', type=str,
+                        default=None,
+                        help=('JSON schema file (None)'))
     args = parser.parse_args()
+    global schema_file
+    schema_file = args.json
     utils.config_init(None, [args.config])
     bottle.run(host=args.host, port=args.port)

tools/run_dragonflow.sh

@@ -1,5 +1,6 @@
 #!/bin/bash
 
+VERB=""
 # First get all the arguments
 while test ${#} -gt 0; do
   case $1 in
@@ -31,8 +32,12 @@ while test ${#} -gt 0; do
       break
       ;;
     *)
-      echo >&2 "Unknown command line argument: $1"
-      exit 1
+      if [ -n "$VERB" ]; then
+        echo >&2 "Unknown command line argument: $1"
+        exit 1
+      fi
+      VERB=$1
+      shift
       ;;
   esac
   shift
@@ -69,8 +74,16 @@ if [ -n "$DB_INIT" ]; then
   df-db init
 fi
 
-if [ -z "$DF_NO_CONTROLLER" ]; then
-  /usr/local/bin/df-local-controller --config-file /etc/dragonflow/dragonflow.ini
-elif [ -z "$DF_NO_BASH" ]; then
-  /bin/bash
-fi
+case "$VERB" in
+  ""|"controller")
+    /usr/local/bin/df-local-controller --config-file /etc/dragonflow/dragonflow.ini
+    ;;
+  "bash")
+    /bin/bash
+    ;;
+  "rest")
+    df-model -j -o /var/dragonflow_model.json
+    pip install bottle
+    /usr/local/bin/df-rest-service --config /etc/dragonflow/dragonflow.ini --host 0.0.0.0 --json /var/dragonflow_model.json
+    ;;
+esac