# The CouchApp Filesystem Mapping¶

The couchapp script has a cool way of pushing files to CouchDB’s design documents. The filesystem mapping is done via the couchdbkit Python library.

If you have folders like:

myapp/
views/
foobar/
map.js
reduce.js


It will create a design document like this:

{
"_id" : "_design/myapp",
"views" : {
"foobar" : {
"map" : "contents of map.js",
"reduce" : "contents of reduce.js"
}
}
}


This is designed to make it so you get proper syntax highlighting in your text editor.

## Complete Filesystem-to-Design Doc Mapping Example¶

myapp/
_attachments/
images/
logo.png
_docs/
sample.json
doc_needing_encoding/
_id (the ID for the document as text on the first line of this file)
title (same as ID, just for the title field. Repeat pattern as needed)
content.html (HTML content that will be encoded when it's added to the JSON doc)
lists/
xml.js
rewrites.js
shows/
preview.js
xml.js
in-place.js
views/
foobar/
map.js
reduce.js
validate_doc_update.js


The _attachments folder will turn each file into an attachment on the resulting Design Document. The attachments will be named based on their file path (ex: “image/logo.png”).

The contents of the _docs folder are turned into actual JSON documents in CouchDB. The contents of the .json files will be input exactly as they are in the file. The name of the document with be either the file name or the _id field from the JSON object in that file.

Folders under _docs will be turned into documents with each file in the folder being a key/value pair in the resulting JSON document. HTML and XML files (and maybe others?) will be JSON encoded before being added to the JSON document. An _id file will be used (if present) as the ID of the new document. Otherwise the folder name will become the ID.

The rest of the folder structure above will become this JSON Design Document

{
"_id" : "_design/myapp",
"_attachments": {
"images/logo.png": {
"content_type": "image/png",
"revpos": 1,
"digest": "md5-GDPL+eLwE7kzEDWY7X4KdQ==",
"length": 886,
"stub": true
}
},
"lists": {
"xml": "function..."
},
"rewrites": "function...",
"shows": {
"preview": "function...",
"xml": "function..."
}