/flowchart.js

Draws simple SVG flow chart diagrams from textual representation of the diagram

Primary LanguageJavaScriptMIT LicenseMIT

JS.ORG

flowchart.js is a flowchart DSL and SVG render that runs in the browser and terminal.

Nodes and connections are defined separately so that nodes can be reused and connections can be quickly changed. Fine grain changes to node and connection style can also be made right in the DSL.

Example

st=>start: Start:>http://www.google.com[blank]
e=>end:>http://www.google.com
op1=>operation: My Operation
sub1=>subroutine: My Subroutine
cond=>condition: Yes
or No?:>http://www.google.com
io=>inputoutput: catch something...
para=>parallel: parallel tasks

st->op1->cond
cond(yes)->io->e
cond(no)->para
para(path1, bottom)->sub1(right)->op1
para(path2, top)->op1

Example Flowchart

CLI

See francoislaberge/diagrams on how to flowchart.js in the terminal.

Browser Usage

flowchart.js is on CDNJS, feel free to use it.

You will also need Raphaël, which is also on CDNJS.

The demo html page is at example/index.html.

Node Syntax

nodeName=>nodeType: nodeText[|flowstate][:>urlLink]

Items in [] are optional.

nodeName defines the nodes variable name within the flowchart document.

nodeType defines what type the node is. See Node Types for more information.

nodeText is the text that will be inserted into the node. Newlines are allowed and will be reflected in the rendered node text.

flowstate is optional and uses the | operator that specifies extra styling for the node.

urlLink is optional and uses the :> operator to specify the url to link to.

Node Types

Defines the shape that the node will take.

start

Used as the first node where flows start from. Default text is Start.

start image

st=>start: start

end

Used as the last node where a flow ends. Default text is End.

end image

e=>end: end

operation

Indicates that an operation needs to happen in the flow.

operation image

op1=>operation: operation

inputoutput

Indicates that IO happens in a flow.

inputoutput image

io=>inputoutput: inputoutput

subroutine

Indicates that a subroutine happens in the flow and that there should be another flowchart that documents this subroutine.

subroutine image

sub1=>subroutine: subroutine

condition

Allows for a conditional or logical statement to direct the flow into one of two paths.

condition image

cond=>condition: condition
Yes or No?

parallel

Allows for multiple flows to happen simultaneously.

parallel image

para=>parallel: parallel

Connections

Connections are defined in their own section below the node definitions. The -> operator specifies a connection from one node to another like nodeVar1->nodeVar2->nodeVar3.

Not all nodes need to be specified in one string and can be separaged like so

nodeVar1->nodeVar2
nodeVar2->nodeVar3

Connection syntax is as follows:

<node variable name>[(<specification1>[, <specification2])]-><node variable name>[[(<specification1>[, <specification2])]-><node variable name>]

Items in [] are optional.

Directions

The following directions are available and define the direction the connection will leave the node from. If there are more than one specifiers, it is always the last. All nodes have a default direction making this an optional specification. <direction> will be used to indicate that one of the following should be used in its place.

  • left
  • right
  • top
  • bottom

Node Specific Specifiers by Type

Each node variables has optional specifiers, like direction, and some have special specifiers depending on the node type that are defined below. Specifiers are added after the variable name in () and separated with , like nodeVar(spec1, spec2).

start

Optional direction

startVar(<direction>)->nextNode

end

No specifications because connections only go to the end node and do not leave from it.

previousNode->endVar

operation

Optional direction

operationVar(<direction>)->nextNode

inputoutput

Optional direction

inputoutputVar(<direction>)->nextNode

subroutine

Optional direction

subroutineVar(<direction>)->nextNode

condition

Required logical specification of yes or no

Optional direction

conditionalVar(yes, <direction>)->nextNode1
conditionalVar(no,  <direction>)->nextNode2

parallel

Required path specification of path1, path2, or path3

Optional direction

parallelVar(path1, <direction>)->nextNode1
parallelVar(path2, <direction>)->nextNode2
parallelVar(path3, <direction>)->nextNode3

Links

A external link can be added to a node with the :> operator.

The st node is linked to http://www.google.com and will open a new tab because [blank] is at the end of the URL.

The e node is linked to http://www.yahoo.com and will cause the page to navigate to that page instead of opening a new tab.

st=>start: Start:>http://www.google.com[blank]
e=>end: End:>http://www.yahoo.com

Advice

Symbols that should possibly not be used in the text: => and -> and :> and | and @> and :$

If you want to emphasize a specific path in your flowchart, you can additionally define it like this:

st@>op1({"stroke":"Red"})@>cond({"stroke":"Red","stroke-width":6,"arrow-end":"classic-wide-long"})@>c2({"stroke":"Red"})@>op2({"stroke":"Red"})@>e({"stroke":"Red"})

Custom names for branches

st=>start: Start:>http://www.google.com[blank]
e=>end:>http://www.google.com
op1=>operation: My Operation
sub1=>subroutine: My Subroutine
cond=>condition: linear or polynomial :>http://www.google.com
io=>inputoutput: catch something...
para=>parallel: 3 possibilities

st->op1->cond
cond(true@linear)->io->e
cond(false@polynomial)->sub1(right)
sub1(right)->para
para(path1@an1, top)->cond
para(path2@an2, right)->op1
para(path3@an3, bottom)->e
Demonstration

img

Contributors

via GitHub

Thanks

Many thanks to js-sequence-diagrams which greatly inspired this project, and forms the basis for the syntax.

Licence

Copyright (c) 2021 Adriano Raiano

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The preceding copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.