PyFlowchart
PyFlowchart produces flowcharts in flowchart.js flowchart DSL, a widely used flow chart textual representation. It’s easy to convert these flowcharts text into a picture via flowchart.js.org, francoislaberge/diagrams, or some markdown editors.
Get PyFlowchart
Quick Start
To flowchartlize your python codes in example.py ，run:
$ python3 -m pyflowchart example.py
PyFlowchart will output the generated flowchart.js DSL. Go to http://flowchart.js.org or use editors like Typora to turn the output code into a rendered diagram.
To specify a function (or a method in a class) to flowchartlize:
$ python3 -m pyflowchart example.py -f function_name $ python3 -m pyflowchart example.py -f ClassName.method_name 🎉 Now you are ready to enjoy the flowchartlization.
Keep reading this document to learn more usages.
Flowchart in Python
PyFlowchart allows you to write a flowchart in Python which could be translated into the flowchart.js DSL automatically.
PyFlowchart supports flowchart.js node types:
- StartNode
- OperationNode
- ConditionNode
- InputOutputNode
- SubroutineNode
- EndNode
Nodes can be connected by connect() method ( connect_
Get a Flowchart with your start node and call its flowchart() method to generate flowchart.js flowchart DSL：
op line starts from the right of sub Output:
st0=>start: start a_pyflow_test op1=>operation: do something cond2=>condition: Yes or No? io3=>inputoutput: output: something. e5=>end: end a_pyflow_test sub4=>subroutine: A Subroutine st0->op1 op1->cond2 cond2-> cond2-> cond2(yes)->io3 io3->e5 cond2(no)->sub4 sub4(right)->op1 Then you can visit http://flowchart.js.org and translate the generated textual representation into SVG flow chart diagrams:
P.S. Many Markdown editors (for example, Typora) support this flowchart syntax, too (reference: Typora doc about flowchart). And if you prefer CLI, see francoislaberge/diagrams.
Set Params to Nodes
Since v0.2.0, we support a Node.set_param(key, value) method to generate flowchart like this:
element(param1=value1,param2=value2)=>start: Start And for convenience, there are grammar sugars to set param align-next=no for ConditionNodes:
This usually works with a connect_direction customization:
The generated flowchart will look like:
cond(align-next=no)=>condition: Yes or No? . cond(yes,right)->op Python to Flowchart
PyFlowchart can also translate your Python Codes into Flowcharts.
For example, you got a simple.py :
Run PyFlowchart in CLI to generate flowchart code:
$ python3 -m pyflowchart simple.py
Advanced Usages
As mentioned above, we use Flowchart.from_code to translate Python codes into Flowcharts. The from_code is defined as:
PyFlowchart CLI is a 1:1 interface for this function:
python3 -m pyflowchart FIELD code_file
Let’s talk about those three args:
- field : str: Specify a field of code to generate a flowchart
- inner : bool: True to parse the body of field; whereas False to parse the body as a single object.
- simplify : bool: for If & Loop statements: simplify the one-line-body or not
- conds_align : bool: improve the flowchart of consecutive If statements converted from python code. (Beta)
field
the field is the path to a field (i.e. a function) you want to draw a flowchart.
For example.py above, available paths are:
- "" (means the whole code) - "foo" - "Bar.buzz" - "Bar.buzz.g" To generate a flowchart of Bar.buzz.g ：
python3 -m pyflowchart example.py -f Bar.buzz.g
inner
inner controls parser’s behaving. Techly, inner=True means parsing field.body , while inner=False parses [field] . So, if inner=True , pyflowchart will look into the field, otherwise, it takes the field as a node.
For CLI, adding an argument -i means inner=True , else inner=False .
simplify
simplify is for If & Loop statements: simplify the one-line-body.
conds-align (Beta)
Improve the flowchart of consecutive If statements converted from python code with the new feature of v0.2.0 .
Beautify Flowcharts
Sometimes, the generated flowchart is awful. In those cases, you are encouraged to modify the generated flowchart code by yourself OR consider making your python source code at bottom more clear if it’s exceedingly complex.
TODOs
$ pyflowchart example.py -o flowchart.svg
Depends on node.js and flowchart.js .
Well, I guess a GUI for PyFlowchart may be remarkable. Pasting your code into it, the flowchart DSL will be generated just in time, and the flowchart will be shown aside.
Sadly, I am too busy (pronounced as [ˈlеizi] ——lazy) to code these ideas. Please submit an issue to push me on. Or, PR to make it by yourself. I cannot wait to appreciate your great contribution!
References
License
Copyright 2020-2022 CDFMLR. All rights reserved.
Licensed under the MIT License.