svn-to-git-migration-tools

createSVNAuthorTransform.py

# Copyright 2016 Brad van der Laan
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#   http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

import sys
import subprocess
import shlex

def print_help_message():
    print("===============================================")
    print("  Create SVN Author Transform File For Git")
    print("                                  Version 1.0.0")
    print("===============================================")
    print("This script will retrieve all the SVN authors")
    print("for the given SVN repository and produce a transform")
    print("file which can be used to convert the SVN authors")
    print("to proper Git authors when converting from SVN to Git.")
    print("")
    print("This python script wrapper was created by me but the")
    print("bash script was taken from John Albin")
    print("   http://john.albin.net/git/convert-subversion-to-git")
    print("")
    print("Example:")
    print("    python createSVNAuthorTransform.py svn://myRepo")
    print("OR")
    print("    python createSVNAuthorTransform.py svn://myRepo author-transform.txt")
    print("")
    print("The first example will output to author-transform.txt by default the second")
    print("example lets you specify where to save the list of SVN authors.")


if __name__ == "__main__":
    if len(sys.argv) > 1:
        svnRepoUrl = sys.argv[1]
        outputFileName = "authors-transform.txt"

        if len(sys.argv) == 3:
            outputFileName = sys.argv[2]

        print("================================")
        print("Generating SVN Author Transform File")
        print("SVN Repository: ", svnRepoUrl)
        print("Transform File: ", outputFileName)

        firstCommand = "svn log -q " + svnRepoUrl
        firstArgs = shlex.split(firstCommand)

        secondCommand = "awk -F \"'|'\" '/^r/ {sub(\"^ \", \"\", $2); sub(\" $\", \"\", $2); print $2\" = \"$2\" <\"$2\">\"}'"
        secondArgs = shlex.split(secondCommand)

        getSVNAuthors = subprocess.Popen(firstArgs, stdout=subprocess.PIPE)
        filterSVNAuthors = subprocess.Popen(secondArgs, stdin=getSVNAuthors.stdout, stdout=subprocess.PIPE)
        getSVNAuthors.stdout.close()
        output,err = filterSVNAuthors.communicate()
        
        unique_list_of_authors = set(output.decode("utf-8").split('\n'))
        with open(outputFileName, 'wb', 0) as outfile:
            for line in unique_list_of_authors:
                outfile.write((line + '\n').encode("utf-8"))
        print("================================")
    else:
        print_help_message()