tAdd docker2sh.py. - docker2sh - Convert Dockerfiles into shell scripts
(HTM) git clone https://git.parazyd.org/docker2sh
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---
(DIR) commit 0c6fe99b9d8031c830abbab1a05d18757fd37d32
(DIR) parent 8a0b794dd328b411a64ba250be772ad675ed8f12
(HTM) Author: parazyd <parazyd@dyne.org>
Date: Wed, 20 Nov 2019 14:11:08 +0100
Add docker2sh.py.
Diffstat:
A docker2sh.py | 176 +++++++++++++++++++++++++++++++
1 file changed, 176 insertions(+), 0 deletions(-)
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(DIR) diff --git a/docker2sh.py b/docker2sh.py
t@@ -0,0 +1,176 @@
+#!/usr/bin/env python3
+# Copyright (c) 2018-2019 Dyne.org Foundation
+# docker2sh is maintained by Ivan J. <parazyd@dyne.org>
+#
+# This source code is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This software is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this source code. If not, see <http://www.gnu.org/licenses/>.
+
+"""
+Dockerfile parser module
+"""
+from argparse import ArgumentParser
+from base64 import b64encode
+from bz2 import compress
+from os.path import dirname, join
+from sys import stdin
+import json
+import re
+
+
+def rstrip_backslash(line):
+ """
+ Strip backslashes from end of line
+ """
+ line = line.rstrip()
+ if line.endswith('\\'):
+ return line[:-1]
+ return line
+
+
+def compress_and_b64(file, basepath=None):
+ """
+ Compress a file and turn it to base64 for output
+ """
+ spl = file.split()
+ if basepath:
+ file = open(join(basepath, spl[0])).read()
+ else:
+ file = open(spl[0]).read()
+
+ comp = compress(file.encode())
+ b64 = b64encode(comp)
+
+ cat = 'cat << __EOFF__ | base64 -d | bunzip2 | sudo tee %s >/dev/null' % (spl[1])
+ return '\n'.join([cat, b64.decode(), '__EOFF__']) + '\n'
+
+
+def parse_instruction(inst, dfile=None):
+ """
+ Method for translating Dockerfile instructions to shell script
+ """
+ ins = inst['instruction'].upper()
+ val = inst['value']
+
+ # Valid Dockerfile instructions
+ cmds = ['ADD', 'ARG', 'CMD', 'COPY', 'ENTRYPOINT', 'ENV', 'EXPOSE', 'FROM',
+ 'HEALTHCHECK', 'LABEL', 'MAINTAINER', 'ONBUILD', 'RUN', 'SHELL',
+ 'STOPSIGNAL', 'USER', 'VOLUME', 'WORKDIR']
+
+ if ins == 'ADD':
+ cmds.remove(ins)
+ val = val.replace('$', '\\$')
+ args = val.split(' ')
+ return 'wget -O %s %s\n' % (args[1], args[0])
+
+ if ins == 'ARG':
+ cmds.remove(ins)
+ return '%s\n' % val
+
+ if ins == 'ENV':
+ cmds.remove(ins)
+ if '=' not in val:
+ val = val.replace(' ', '=', 1)
+ return 'export %s\n' % val
+
+ if ins == 'RUN':
+ cmds.remove(ins)
+ # Replace `` with $()
+ while '`' in val:
+ val = val.replace('`', '"$(', 1)
+ val = val.replace('`', ')"', 1)
+ return '%s\n' % val.replace('$', '\\$')
+
+ if ins == 'WORKDIR':
+ cmds.remove(ins)
+ return 'mkdir -p %s && cd %s\n' % (val, val)
+
+ if ins == 'COPY':
+ cmds.remove(ins)
+ if '/' in dfile:
+ return compress_and_b64(val, basepath=dirname(dfile))
+ return compress_and_b64(val)
+
+ if ins in cmds:
+ # TODO: Look at CMD being added to /etc/rc.local
+ return '#\n# %s not implemented\n# Instruction: %s %s\n#\n' % \
+ (ins, ins, val)
+
+ return ''
+
+
+def main():
+ """
+ Main parsing routine
+ """
+ parser = ArgumentParser()
+ parser.add_argument('-j', '--json', action='store_true',
+ help='output the data as a JSON structure')
+ parser.add_argument('-s', '--shell', action='store_true',
+ help='output the data as a shell script (default)')
+ parser.add_argument('--keeptabs', action='store_true',
+ help='do not replace \\t (tabs) in the strings')
+ parser.add_argument('Dockerfile')
+ args = parser.parse_args()
+
+ if args.Dockerfile != '-':
+ with open(args.Dockerfile) as file:
+ data = file.read().splitlines()
+ else:
+ data = stdin.read().splitlines()
+
+ instre = re.compile(r'^\s*(\w+)\s+(.*)$')
+ contre = re.compile(r'^.*\\\s*$')
+ commentre = re.compile(r'^\s*#')
+
+ instructions = []
+ lineno = -1
+ in_continuation = False
+ cur_inst = {}
+
+ for line in data:
+ lineno += 1
+ if commentre.match(line):
+ continue
+ if not in_continuation:
+ rematch = instre.match(line)
+ if not rematch:
+ continue
+ cur_inst = {
+ 'instruction': rematch.groups()[0].upper(),
+ 'value': rstrip_backslash(rematch.groups()[1]),
+ }
+ else:
+ if cur_inst['value']:
+ cur_inst['value'] += rstrip_backslash(line)
+ else:
+ cur_inst['value'] = rstrip_backslash(line.lstrip())
+
+ in_continuation = contre.match(line)
+ if not in_continuation and cur_inst is not None:
+ if not args.keeptabs:
+ cur_inst['value'] = cur_inst['value'].replace('\t', '')
+ instructions.append(cur_inst)
+
+ if args.json:
+ print(json.dumps(instructions))
+ return
+
+ # Default to shell script output
+ script = '#!/bin/sh\n'
+ for i in instructions:
+ script += parse_instruction(i, dfile=args.Dockerfile)
+ print(script)
+
+
+if __name__ == '__main__':
+ main()