bsfs applications

1 files changed, 67 insertions, 0 deletions

diff --git a/bsfs/apps/migrate.py b/bsfs/apps/migrate.py
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+++ b/bsfs/apps/migrate.py
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+"""
+
+Part of the BlackStar filesystem (bsfs) module.
+A copy of the license is provided with the project.
+Author: Matthias Baumgartner, 2022
+"""
+# imports
+import argparse
+import json
+import logging
+import sys
+import typing
+
+# bsfs imports
+import bsfs
+
+# exports
+__all__: typing.Sequence[str] = (
+    'main',
+    )
+
+
+## code ##
+
+logger = logging.getLogger(__name__)
+
+def main(argv):
+    """Migrate a storage structure to a modified schema."""
+    parser = argparse.ArgumentParser(description=main.__doc__, prog='migrate')
+    parser.add_argument('--remove', action='store_true', default=False,
+        help='Remove classes that are not specified in the provided schema.')
+    parser.add_argument('config', type=str, default=None,
+        help='Path to the storage config file.')
+    parser.add_argument('schema', nargs=argparse.REMAINDER,
+        help='Paths to schema files. Reads from standard input if no file is supplied.')
+    args = parser.parse_args(argv)
+
+    # load storage config
+    with open(args.config, mode='rt', encoding='UTF-8') as ifile:
+        config = json.load(ifile)
+    # open bsfs storage
+    graph = bsfs.Open(config)
+
+    # initialize schema
+    schema = bsfs.schema.Schema.Empty()
+    if len(args.schema) == 0:
+        # assemble schema from standard input
+        schema = schema + bsfs.schema.Schema.from_string(sys.stdin.read())
+    else:
+        # assemble schema from input files
+        for pth in args.schema:
+            with open(pth, mode='rt', encoding='UTF-8') as ifile:
+                schema = schema + bsfs.schema.Schema.from_string(ifile.read())
+
+    # migrate schema
+    graph.migrate(schema, not args.remove)
+
+    # return the migrated storage
+    return graph
+
+
+## main ##
+
+if __name__ == '__main__':
+    main(sys.argv[1:])
+
+## EOF ##