annex.genmetadata can be set to make git-annex automatically set metadata (year and month) when adding files

1 files changed, 41 insertions, 0 deletions

diff --git a/doc/metadata.mdwn b/doc/metadata.mdwn
new file mode 100644
index 000000000..414a91053
--- /dev/null
+++ b/doc/metadata.mdwn
@@ -0,0 +1,41 @@
+git-annex allows you to store arbitrary metadata about files stored in the
+git-annex repository. The metadata is stored in the `git-annex` branch, and
+so is automatically kept in sync with the rest of git-annex's state, such
+as [[location_tracking]] information.
+
+Some of the things you can do with metadata include:
+
+* Using `git annex metadata file` to show all 
+  the metadata associated with a file.
+* [[tips/metadata_driven_views]]
+* Limiting the files git-annex commands act on to those with
+  or without particular metadata.
+  For example `git annex find --metadata tag=foo --or --metadata tag=bar`
+* Using it in [[preferred_content]] expressions. 
+  For example "tag=important or not author=me"
+
+Each file (actually the underlying key) can have any number of metadata
+fields, which each can have any number of values. For example, to tag
+files, the `tag` field is typically used, with values set to each tag that
+applies to the file.
+
+The field names are freeform (but cannot include spaces). The metadata
+values can contain absolutely anything you like -- but you're recommended
+to keep it simple and reasonably short.
+
+Here are some recommended metadata fields to use:
+
+* `tag` - With each tag being a different value.
+* `year`, `month` - When this particular version of the file came into
+  being.
+  
+To make git-annex automatically set the year and month when adding files,
+run `git config annex.genmetadata true`
+
+git-annex's metadata can be updated in a distributed fashion. For example,
+two users, each with their own clone of a repository, can set and unset
+metadata at the same time, even for the same field of the same file. 
+When they push their changes, `git annex merge` will combine their
+metadata changes in a consistent and (probably) intuitive way.
+
+See [[the metadata design page|design/metadata]] for more details.