alembic-graph

#!/usr/bin/env python
import sys
from graphviz import Digraph

dot = Digraph(comment='alembic')


def split_line(line):
    bases, _, name_and_target = line.partition('->')
    id_and_stuff, _, desc = name_and_target.strip().partition(',')
    desc = desc.strip()

    id_, _, type_ = id_and_stuff.partition(' ')
    id_ = id_.replace('<', '').replace('>', '')
    type_ = type_[1:-1]

    lowers = []
    dependencies = []
    for base in bases.split(' '):
        base = base.strip().replace(',', '')
        if not base:
            continue
        if base.startswith('(') and base.endswith(')'):
            dependencies.append(base.replace('(', '').replace(')', ''))
        else:
            lowers.append(base)

    return id_, lowers, dependencies, desc, type_


for line in sys.stdin.readlines():
    id_, lowers, dependencies, desc, type_ = split_line(line)
    if not id_:
        continue
    dot.node(id_, id_ + ":\n" + desc)
    for lower in lowers:
        dot.edge(lower, id_)
    for dep in dependencies:
        dot.edge(id_, dep, label='depends on', _attributes=dict(style='dotted'))

dot.render('/tmp/alembic.gv', view=True)

use: alembic history | alembic-graph
needs graphviz pip module and dot executable. you get a pdf

funny i wrote a similar script on the weekend which uses alembic walk_revisions function and a config instead of the pipe. i'll post it tomorrow.

i think depends_on parents aren't displayed correctly here (in my version too)

yeah i didn't know what (<revision_id>) in the output was, but then remembered the depends on thing ... fixed it
and i used the pipe on purpose because i didnt want to fiddle around with configs or how alembic does it.

this is just a small hacky script but it worked for me ;)

Nice!

You should insert it after line 24 to avoid invalid dot node id <base> which comes from alembic history.

        if base.startswith('<') and base.endswith('>'):
            dependencies.append(base.replace('<', '').replace('>', ''))

FYI: https://gist.github.com/weaming/2463b0ec3f6ee79f5d38dcfb8b7a0b94