openstack/mistral
Code Issues Proposed changes

Added JavaScript evaluator which doesn't require a compilation

Browse Source 
* Added new JavaScript evaluator py_mini_racer. Advantages:
    * is distributed as wheel package
    * supports differences platforms
    * live project
* BUILD_V8EVAL was removed because it was replaced by py_mini_racer in
Mistral Docker image
* Added stevedore integration to javascript evaluators
* Refreshed javascript tests. Add test for py_mini_racer evaluator
* Install py_mini_racer library in during mistral test
* Refreshed javascript action doc

Change-Id: Id9d558b9b8374a2c2639e10cb1868f4e67f96e86
Implements: blueprint mistral-add-py-mini-racer-javascript-evaluator
Signed-off-by: Vitalii Solodilov <mcdkr@yandex.ru>
This commit is contained in:
Vitalii Solodilov 2018-04-22 13:48:13 +04:00 committed by Vitalii Solodilov
parent 7adea45910
commit 5f89e2e71f
12 changed files with 136 additions and 114 deletions
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44
doc/source/user/wf_lang_v2.rst
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@ -1108,30 +1108,23 @@ Input parameters:
- **script** - The text of JavaScript snippet that needs to be
executed. *Required*.
- **context** - This object will be assigned to the *$* javascript variable.
The default value is None.
**To use std.javascript, it is needed to install a number of
dependencies and JS engine.** Currently Mistral uses only V8 Engine and its
wrapper - PyV8. For installing it, do the next steps:
To use std.javascript, it is needed to install the
`py_mini_racer <https://github.com/sqreen/PyMiniRacer>`__ and set
*py_mini_racer* to *js_implementation* parameter in *mistral.conf*:
1. Install required libraries - boost, g++, libtool, autoconf, subversion,
libv8-legacy-dev: On Ubuntu::
.. code-block:: bash
$ sudo apt-get install libboost-all-dev g++ libtool autoconf libv8-legacy-dev subversion make
pip install py_mini_racer
2. Checkout last version of PyV8::
Other available implementations:
$ svn checkout http://pyv8.googlecode.com/svn/trunk/ pyv8
$ cd pyv8
- `pyv8 <https://code.google.com/archive/p/pyv8>`__
- `v8eval <https://github.com/sony/v8eval>`__
3. Build PyV8 - it will checkout last V8 trunk, build it, and then build PyV8::
$ sudo python setup.py build
4. Install PyV8::
$ sudo python setup.py install
Example:
Example with *context*:
.. code-block:: mistral
@ -1141,8 +1134,6 @@ Example:
generate_uuid:
  description: Generates a Universal Unique ID
  type: direct
  input:
    - radix: 16
@ -1151,7 +1142,7 @@ Example:
  tasks:
    generate_uuid_task:
      action: std.javascript
      action: std.js
      input:
        context: <% $ %>
        script: |
@ -1160,7 +1151,7 @@ Example:
                  return v.toString($.radix);
          });
      publish:
        generated_uuid: <% task(generate_uuid_task).result %>
        generated_uuid: <% task().result %>
Another example for getting the current date and time:
@ -1172,21 +1163,18 @@ Another example for getting the current date and time:
  get_date_workflow:
    description: Get the current date
    type: direct
    output:
      current_date: <% $.current_date %>
    tasks:
      get_date_task:
        action: std.javascript
        action: std.js
        input:
          context: <% $ %>
          script: |
            var date = new Date();
            return date; # returns "2015-07-12T10:32:12.460000" or use date.toLocaleDateString() for "Sunday, July 12, 2015"
            return date; // returns "2015-07-12T10:32:12.460000" or use date.toLocaleDateString() for "Sunday, July 12, 2015"
        publish:
          current_date: <% task(get_date_task).result %>
          current_date: <% task().result %>
Ad-hoc actions
^^^^^^^^^^^^^^

2
mistral/config.py
View File

@ -90,7 +90,7 @@ api_opts = [
js_impl_opt = cfg.StrOpt(
'js_implementation',
default='pyv8',
choices=['pyv8', 'v8eval'],
choices=['pyv8', 'v8eval', 'py_mini_racer'],
help=_('The JavaScript implementation to be used by the std.javascript '
'action to evaluate scripts.')
)

109
mistral/tests/unit/engine/test_javascript_action.py
View File

@ -14,10 +14,11 @@
import mock
from oslo_config import cfg
from oslo_utils import importutils
import testtools
from mistral.db.v2 import api as db_api
from mistral.services import workbooks as wb_service
from mistral.services import workflows as wf_service
from mistral.tests.unit.engine import base
from mistral.utils import javascript
from mistral.workflow import states
@ -28,83 +29,81 @@ from mistral.workflow import states
cfg.CONF.set_default('auth_enable', False, group='pecan')
WORKBOOK = """
---
JAVASCRIPT_WORKFLOW = """
version: "2.0"
wf:
input:
- length
tasks:
task1:
action: std.javascript
input:
script: |
let numberSequence = Array.from({length: $['length']},
(x, i) => i);
let evenNumbers = numberSequence.filter(x => x % 2 === 0);
name: test_js
workflows:
js_test:
type: direct
input:
- num
tasks:
task1:
description: |
This task reads variable from context,
increasing its value 10 times, writes result to context and
returns 100 (expected result)
action: std.javascript
input:
script: |
return $['num'] * 10
context: <% $ %>
publish:
result: <% task(task1).result %>
return evenNumbers.length;
context: <% $ %>
publish:
res: <% task().result %>
"""
def fake_evaluate(_, context):
return context['num'] * 10
return context['length'] / 2
class JavaScriptEngineTest(base.EngineTestCase):
@testtools.skip('It requires installed JS engine.')
def test_javascript_action(self):
wb_service.create_workbook_v2(WORKBOOK)
# Start workflow.
wf_ex = self.engine.start_workflow(
'test_js.js_test',
wf_input={'num': 50}
@testtools.skipIf(not importutils.try_import('py_mini_racer'),
'This test requires that py_mini_racer library was '
'installed')
def test_py_mini_racer_javascript_action(self):
cfg.CONF.set_default(
'js_implementation',
'py_mini_racer'
)
length = 1000
self.await_workflow_success(wf_ex.id)
# Note: We need to reread execution to access related tasks.
wf_ex = db_api.get_workflow_execution(wf_ex.id)
task_ex = wf_ex.task_executions[0]
self.assertEqual(states.SUCCESS, task_ex.state)
self.assertDictEqual({}, task_ex.runtime_context)
self.assertEqual(500, task_ex.published['num_10_times'])
self.assertEqual(100, task_ex.published['result'])
@mock.patch.object(javascript, 'evaluate', fake_evaluate)
def test_fake_javascript_action_data_context(self):
wb_service.create_workbook_v2(WORKBOOK)
wf_service.create_workflows(JAVASCRIPT_WORKFLOW)
# Start workflow.
wf_ex = self.engine.start_workflow(
'test_js.js_test',
wf_input={'num': 50}
'wf',
wf_input={'length': length}
)
self.await_workflow_success(wf_ex.id)
with db_api.transaction():
# Note: We need to reread execution to access related tasks.
wf_ex = db_api.get_workflow_execution(wf_ex.id)
task_ex = wf_ex.task_executions[0]
self.assertEqual(states.SUCCESS, task_ex.state)
self.assertDictEqual({}, task_ex.runtime_context)
self.assertEqual(500, task_ex.published['result'])
self.assertEqual(length / 2, task_ex.published['res'])
@mock.patch.object(javascript, 'evaluate', fake_evaluate)
def test_fake_javascript_action_data_context(self):
length = 1000
wf_service.create_workflows(JAVASCRIPT_WORKFLOW)
# Start workflow.
wf_ex = self.engine.start_workflow(
'wf',
wf_input={'length': length}
)
self.await_workflow_success(wf_ex.id)
with db_api.transaction():
wf_ex = db_api.get_workflow_execution(wf_ex.id)
task_ex = wf_ex.task_executions[0]
self.assertEqual(states.SUCCESS, task_ex.state)
self.assertDictEqual({}, task_ex.runtime_context)
self.assertEqual(length / 2, task_ex.published['res'])

54
mistral/utils/javascript.py
View File

@ -15,20 +15,32 @@
import abc
import json
from oslo_utils import importutils
from mistral import config as cfg
from mistral import exceptions as exc
from oslo_utils import importutils
from stevedore import driver
from stevedore import extension
_PYV8 = importutils.try_import('PyV8')
_V8EVAL = importutils.try_import('v8eval')
_PY_MINI_RACER = importutils.try_import('py_mini_racer.py_mini_racer')
_EVALUATOR = None
class JSEvaluator(object):
@classmethod
@abc.abstractmethod
def evaluate(cls, script, context):
"""Executes given JavaScript."""
"""Executes given JavaScript.
:param script: The text of JavaScript snippet that needs to be
executed.
context: This object will be assigned to the $ javascript
variable.
:return result of evaluated javascript code.
:raise MistralException: if corresponding js library is not installed.
"""
pass
@ -61,9 +73,39 @@ class V8EvalEvaluator(JSEvaluator):
encoding='UTF-8'))
EVALUATOR = (V8EvalEvaluator if cfg.CONF.js_implementation == 'v8eval'
else PyV8Evaluator)
class PyMiniRacerEvaluator(JSEvaluator):
@classmethod
def evaluate(cls, script, context):
if not _PY_MINI_RACER:
raise exc.MistralException(
"PyMiniRacer module is not available. Please install "
"PyMiniRacer."
)
ctx = _PY_MINI_RACER.MiniRacer()
return ctx.eval(('$ = {}; {}'.format(json.dumps(context), script)))
_mgr = extension.ExtensionManager(
namespace='mistral.expression.evaluators',
invoke_on_load=False
)
def get_js_evaluator():
global _EVALUATOR
if not _EVALUATOR:
mgr = driver.DriverManager(
'mistral.js.implementation',
cfg.CONF.js_implementation,
invoke_on_load=True
)
_EVALUATOR = mgr.driver
return _EVALUATOR
def evaluate(script, context):
return EVALUATOR.evaluate(script, context)
return get_js_evaluator().evaluate(script, context)

6
releasenotes/notes/add-py-mini-racer-javascript-evaluator-9d8f9e0e36504d72.yaml Normal file
View File

@ -0,0 +1,6 @@
---
features:
- |
Added new JavaScript evaluator py_mini_racer. The py_mini_racer package
allows us to get a JavaScript evaluator that doesn't require compilation.
This is much lighter and easier to get started with.

5
setup.cfg
View File

@ -114,3 +114,8 @@ kombu_driver.executors =
pygments.lexers =
mistral = mistral.ext.pygmentplugin:MistralLexer
mistral.js.implementation =
pyv8 = mistral.utils.javascript:PyV8Evaluator
v8eval = mistral.utils.javascript:V8EvalEvaluator
py_mini_racer = mistral.utils.javascript:PyMiniRacerEvaluator

9
tools/docker/DOCKER_README.rst
View File

@ -24,18 +24,11 @@ On the other hand you could execute the following command::
docker build -t mistral -f tools/docker/Dockerfile .
The Mistral Docker image has set of build parameters. **Pay attention**, the
compile of 'V8EVAL' can take a long time.
The Mistral Docker image has a build parameter.
+-------------------------+-------------+--------------------------------------+
|Name |Default value| Description |
+=========================+=============+======================================+
|`BUILD_V8EVAL` |true |If the `BUILD_V8EVAL` equals `true`, |
| | |the `v8eval` library will be build for|
| | |std.javascript action. `Read more <ht |
| | |tps://docs.openstack.org/mistral/lates|
| | |t/user/dsl_v2.html#std-javascript>`_ |
+-------------------------+-------------+----------------------+---------------+
|`BUILD_TEST_DEPENDENCIES`|false |If the `BUILD_TEST_DEPENDENCIES` |
| | |equals `true`, the Mistral test |
| | |dependencies will be installed inside |

11
tools/docker/Dockerfile
View File

@ -18,20 +18,13 @@ RUN apt-get -qq update && \
crudini \
curl \
git \
cmake \
gcc \
libuv1 \
swig \
mc \
libuv1-dev && \
curl -f -o /tmp/get-pip.py https://bootstrap.pypa.io/get-pip.py && \
python /tmp/get-pip.py && rm /tmp/get-pip.py
RUN pip install pymysql psycopg2
ARG BUILD_V8EVAL="true"
RUN if ${BUILD_V8EVAL} ; then \
pip install -v v8eval && python -c 'import v8eval' ; \
fi
RUN pip install pymysql psycopg2 py_mini_racer
ENV MISTRAL_DIR="/opt/stack/mistral" \
TMP_CONSTRAINTS="/tmp/upper-constraints.txt" \

5
tools/docker/docker-compose/mistral-multi-node.yaml
View File

@ -5,7 +5,6 @@ services:
context: ../../..
dockerfile: tools/docker/Dockerfile
args:
BUILD_V8EVAL: "false"
BUILD_TEST_DEPENDENCIES: "false"
restart: always
ports:
@ -27,7 +26,6 @@ services:
context: ../../..
dockerfile: tools/docker/Dockerfile
args:
BUILD_V8EVAL: "false"
BUILD_TEST_DEPENDENCIES: "false"
restart: always
networks:
@ -45,7 +43,6 @@ services:
context: ../../..
dockerfile: tools/docker/Dockerfile
args:
BUILD_V8EVAL: "false"
BUILD_TEST_DEPENDENCIES: "false"
restart: always
networks:
@ -62,7 +59,6 @@ services:
context: ../../..
dockerfile: tools/docker/Dockerfile
args:
BUILD_V8EVAL: "false"
BUILD_TEST_DEPENDENCIES: "false"
restart: always
networks:
@ -80,7 +76,6 @@ services:
context: ../../..
dockerfile: tools/docker/Dockerfile
args:
BUILD_V8EVAL: "false"
BUILD_TEST_DEPENDENCIES: "false"
restart: always
networks:

1
tools/docker/docker-compose/mistral-single-node.yaml
View File

@ -5,7 +5,6 @@ services:
context: ../../..
dockerfile: "tools/docker/Dockerfile"
args:
BUILD_V8EVAL: "false"
BUILD_TEST_DEPENDENCIES: "false"
restart: always
ports:

2
tools/docker/start.sh
View File

@ -8,7 +8,7 @@ if [ ! -f ${CONFIG_FILE} ]; then
--config-file "${MISTRAL_DIR}/tools/config/config-generator.mistral.conf" \
--output-file "${CONFIG_FILE}"
${INI_SET} DEFAULT js_implementation v8eval
${INI_SET} DEFAULT js_implementation py_mini_racer
${INI_SET} oslo_policy policy_file "${MISTRAL_DIR}/etc/policy.json"
${INI_SET} pecan auth_enable false
${INI_SET} DEFAULT transport_url "${MESSAGE_BROKER_URL}"

2
tox.ini
View File

@ -14,6 +14,8 @@ deps =
-c{env:UPPER_CONSTRAINTS_FILE:https://git.openstack.org/cgit/openstack/requirements/plain/upper-constraints.txt}
-r{toxinidir}/test-requirements.txt
-r{toxinidir}/requirements.txt
# javascript engine
py_mini_racer
commands =
rm -f .testrepository/times.dbm
find . -type f -name "*.pyc" -delete