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seqdiag generates sequence-diagram image from text

Project description

seqdiag generate sequence-diagram image file from spec-text file. CI build status Latest PyPI version Number of PyPI downloads


  • Generate sequence-diagram from dot like text (basic feature).

  • Multilingualization for node-label (utf-8 only).

You can get some examples and generated images on .


Use easy_install or pip:

$ sudo easy_install seqdiag


$ sudo pip seqdiag

Copy and modify ini file. example:

$ cp <seqdiag installed path>/blockdiag/examples/simple.diag .
$ vi simple.diag

Please refer to spec-text setting sample section for the format of the simpla.diag configuration file.

spec-text setting sample

Few examples are available. You can get more examples at .


simple.diag is simply define nodes and transitions by dot-like text format:

diagram {
  browser  -> webserver [label = "GET /index.html"];
  browser <-- webserver;
  browser  -> webserver [label = "POST /blog/comment"];
              webserver  -> database [label = "INSERT comment"];
              webserver <-- database;
  browser <-- webserver;


Execute seqdiag command:

$ seqdiag simple.diag
$ ls simple.png


  • Python 3.7 or later

  • blockdiag 1.5.0 or later

  • funcparserlib 0.3.6 or later

  • reportlab (optional)

  • wand and imagemagick (optional)

  • setuptools


Apache License 2.0

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seqdiag-3.0.0.tar.gz (2.6 MB view hashes)

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seqdiag-3.0.0-py3-none-any.whl (2.6 MB view hashes)

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