Python 1.6

Extension ID

com.castsoftware.python

What's new?

See Python 1.6 - Release Notes.

Description

This extension provides support for Python. If your application contains Python source code (both .py and .jy extensions are supported) and you want to view these object types and their links with other objects, then you should install this extension.

Files analyzed

Supported Python versions

The following table displays the supported versions matrix:

Version	Support
3.x
2.x
1.x

Framework support

Web Service Frameworks	Client-side requests	Server-side operations
Aiohttp (https://docs.aiohttp.org/en/stable/)
Bottle: https://bottlepy.org/docs/dev/	N/A
CherryPy (https://docs.cherrypy.dev/en/latest/)	N/A
Django: https://www.djangoproject.com/	N/A
Falcon (https://falconframework.org/)	N/A
FastAPI (https://fastapi.tiangolo.com/)	N/A
Flask (https://flask.palletsprojects.com/)	N/A
http.client (https://docs.python.org/3/library/http.client.html)		N/A
httplib (https://docs.python.org/2/library/httplib.html)		N/A
httplib2 (https://pypi.org/project/httplib2/)		N/A
Nameko: https://github.com/nameko/nameko	N/A
Pyramid (https://docs.pylonsproject.org/projects/pyramid/en/latest/index.html)	N/A
Requests (https://docs.python-requests.org/)		N/A
Sanic: https://sanic.readthedocs.io/en/stable/	N/A
Tornado: https://www.tornadoweb.org/en/stable/
urllib (https://docs.python.org/3/library/urllib.html)		N/A
urllib2 (https://docs.python.org/2/library/urllib2.html)		N/A
urllib3 (https://pypi.org/project/urllib3/)		N/A
web2py (http://www.web2py.com/)

Function Point, Quality and Sizing support

This extension provides the following support:

• Function Points (transactions): a green tick indicates that OMG Function Point counting and Transaction Risk Index are supported
• Quality and Sizing: a green tick indicates that CAST can measure size and that a minimum set of Quality Rules exist

Function Points (transactions)	Quality and Sizing	Security

Compatibility

CAST Imaging Core release	Supported
8.3.x

Dependencies with other extensions

Some CAST extensions require the presence of other CAST extensions in order to function correctly. The Python extension requires that the following other CAST extensions are also installed:

• com.castsoftware.wbslinker
• CAST AIP Internal extension (internal technical extension)

Download and installation instructions

The extension will be automatically downloaded and installed in CAST Console. You can manage the extension using the Application - Extensions interface.

Source code discovery

A discoverer is provided with the extension to automatically detect Python code: a Python project will be discovered for the package's root folder when at least one .py or .jy (jython) file is detected in the root folder or any sub-folders. For every Python project located, one Universal Technology Analysis Unit will be created:

Analysis - Automatic skipping of unit-test code and external libraries

The analyzer skips files that are recognized as forming part of testing code, i.e., in principle, code not pertaining to production code. The reason to avoid inclusion of testing code is that many Quality Rule violations are overrepresented in test code, either because code tends to be of poorer quality (certainly not critical) or prevalence of particular testing patterns. Accounting for test code would negatively impact the total score of the project.

Similarly we skip folders that contain external python libraries. Currently we only skip the canonical folders site-packages and dist-packages (the latter being used in certain Linux distributions). Not only analyzing external libraries is discouraged, but it can interfere with correct interpretation of supported libraries and frameworks, and have a serious impact in memory consumption and overall analysis performance.

The heuristics used by the analyzer are based on detecting (unit-test) library imports, and file and path naming conventions as summarized in the table below: 

What results can you expect?

Once the analysis/snapshot generation has completed, you can view the results in the normal manner:

Python Class and method example

iOS Front-end connected to a Python Flask Back-end.

Objects

Python

Icon	Description
	Python Project, Python External Library
	Python Module
	Python Class
	Python Static Initializer
	Python Method
	Python Script
	Python GET (urllib, urllib2, httplib, httplib2, aiohttp) service Python GET service request Python (Flask, aiohttp) Web Service GET operation Python Web Service Get Operation
	Python POST (urllib, urllib2, httplib, httplib2, aiohttp) service Python POST service request Python (Flask, aiohttp) Web Service POST operation Python Web Service Post Operation
	Python PUT (urllib, urllib2, httplib, httplib2, aiohttp) service Python PUT service request Python (Flask, aiohttp) Web Service PUT operation Python Web Service Post Operation
	Python DELETE (urllib, urllib2, httplib, httplib2, aiohttp) service Python DELETE service request Python Flask, aiohttp Web Service DELETE operation Python Web Service Delete Operation
	Python Web Service Any Operation
	Python Query, Python ORM Mapping, Python File Query
	RabbitMQ Python QueueCall ActiveMQ Python QueueCall IBM MQ Python QueueCall
	RabbitMQ Python QueueReceive ActiveMQ Python QueueReceive IBM MQ Python QueueReceive
	Python Call To Java Program
	Python Call To Generic Program

Amazon Web Services

	Python Call to AWS Lambda Function
	Python Call to Unknown AWS Lambda Function
	Python AWS Lambda GET Operation
	Python AWS Lambda POST Operation
	Python AWS Lambda PUT Operation
	Python AWS Lambda DELETE Operation
	Python AWS Lambda ANY Operation
	Python AWS SQS Publisher, Python AWS SNS Publisher
	Python AWS SQS Receiver, Python AWS SNS Receiver
	Python AWS SQS Unknown Publisher, Python AWS SNS Unknown Publisher
	Python AWS SQS Unknown Receiver, Python AWS SNS Unknown Receiver
	Python S3 Bucket
	Python Unknown S3 Bucket
	Python DynamoDB Database
	Python DynamoDB Table
	Python Unknown DynamoDB Table
	Python Email, Python SMS

Python callable artifact

Python Module, Python Method, and Python Static Initializer objects form part of Python (callable) artifacts.

Python static initializers

The statements of a given class code block are represented by an effective Python Static Initializer object. In this object other class and method definitions are not included. Class docstrings are excluded from this object. This particular code is executed at class-definition time. To represent this in the call-graph, a link between the enclosing Python Module (or Python Method when the class is defined inside a method) and the Static Initializer object as shown in the example below:

# file1.py
 
from file2 import A

# file2.py
 
def f():
    pass
 
def f2():
    pass
 
class A:
 
    f()
 
    def m1(self):
        pass

    f2()
 
# this is code is also executed at import-time.
f2()

Links

The following links are created:

• call links between methods
• inherit link between hierarchically related classes
• refer link from methods to class (constructor call)
• use link between modules through import
• call links between Python callable artifacts and Python Call objects
• call links between Python Call objects and external programs or lambda functions

The following links are created between Python ORM Mapping objects and database table objects:

• useSelectLink in case of SELECT operation
• useDeleteLink in case of DELETE operation
• useInsertLink in case of INSERT operation
• useUpdateLink in case of UPDATE operation
• call links in case of generic operation on S3 buckets

Structural Rules

The following structural rules are provided: 

You can also find a global list here: https://technologies.castsoftware.com/rules?sec=t_1021000&ref=||

Expected results for supported frameworks

Refer the following pages for the results that you can expect for each supported framework:

• Python 1.6 - Analysis Results - Web Service calls and operations support
• Python 1.6 - Analysis Results - Access to databases
• Python 1.6 - Analysis Results - File system access functions
• Python 1.6 - Analysis Results - Message Queues support
• Python 1.6 - Analysis Results - Amazon Web Services
• Python 1.6 - Analysis Results - Calls to external program from Python

Known Limitations

• Not fully supported Python Decorator function.
• The "Avoid disabling certificate check when requesting secured urls" for 'urllib3' is only partially supported by detecting the call to 'urllib3.disable_warnings'.
• Limited Python resolution that leads to missing links:
  • No support for __all__
  • No support for variable of type class, function
• Flask:
• Objects for other web service operations such as PATCH are not generated.
• The endpoint abstraction layer between functions and annotations is not considered. When using  add_url_rule the endpoint argument is taken as the calling function name.
• Cherrypy:

  • Only support default request.dispatcher "cherrypy.dispatch.MethodDispatcher()".

• Java-Python interoperability via Jython is not supported. However the files with the specific extension .jy for Jython is analyzed as a regular Python file.
• Message queues
  •  To generate queue message objects the queue name has to be initialized explicitly in the code (dynamic naming not supported).
• SQLAlchemy:
  • Only raw queries are fully supported.
  • The ORM api for queries is not supported (no links are created towards tables).