Allow to dynamically change webdav data model.

Each webdav file is transformed as a single "enclosure" attachment to a jio document with the same name.

src/jio.storage/drivetojiomapping.js

+/*jslint nomen: true, maxlen: 200*/
+/*global console, RSVP, Blob*/
+(function (jIO) {
+  "use strict";
+
+  /**
+   * The jIO FileSystemBridgeStorage extension
+   *
+   * @class FileSystemBridgeStorage
+   * @constructor
+   */
+  function FileSystemBridgeStorage(spec) {
+    this._sub_storage = jIO.createJIO(spec.sub_storage);
+    this._document_key = "/.jio_documents/";
+    this._attachment_key = "/.jio_attachments/";
+  }
+  var DOCUMENT_EXTENSION = ".json",
+    ROOT = "/";
+
+  FileSystemBridgeStorage.prototype.get = function (param) {
+    var context = this,
+      json_document,
+      explicit_document = false;
+    return new RSVP.Queue()
+
+      // First, try to get explicit reference to the document
+
+      .push(function () {
+        // First get the document itself if it exists
+        return context._sub_storage.getAttachment({
+          "_id": context._document_key,
+          "_attachment": param._id + DOCUMENT_EXTENSION
+        });
+      })
+      .push(function (blob) {
+        return new RSVP.Queue()
+          .push(function () {
+            return jIO.util.readBlobAsText(blob);
+          })
+          .push(function (text) {
+            explicit_document = true;
+            return JSON.parse(text.target.result);
+          });
+      }, function (error) {
+        if ((error instanceof jIO.util.jIOError) && (error.status_code === 404)) {
+          return {};
+        }
+        throw error;
+      })
+
+      // Second, try to get default attachment
+
+      .push(function (result) {
+        json_document = result;
+
+        return context._sub_storage.get({
+          "_id": ROOT
+        });
+      })
+
+      .push(function (directory_document) {
+        if (directory_document._attachments.hasOwnProperty(param._id)) {
+          json_document._attachments = {
+            enclosure: {}
+          };
+        } else {
+          if (!explicit_document) {
+            throw new jIO.util.jIOError("Cannot find document", 404);
+          }
+        }
+        return json_document;
+      });
+
+  };
+
+  FileSystemBridgeStorage.prototype.post = function (param) {
+    var doc_id = param._id;
+
+    if (doc_id === undefined) {
+      doc_id = jIO.util.generateUuid();
+    }
+
+    param._id = doc_id;
+    return this.put(param);
+  };
+
+  FileSystemBridgeStorage.prototype.put = function (param) {
+    var context = this,
+      doc_id = param._id;
+    // XXX Handle conflict!
+    // XXX Put empty enclosure directly if json is empty
+
+    return context._sub_storage.putAttachment({
+      "_id": context._document_key,
+      "_attachment": doc_id + DOCUMENT_EXTENSION,
+      "_blob": new Blob([JSON.stringify(param)], {type: "application/json"})
+    })
+      .push(undefined, function (error) {
+        if ((error instanceof jIO.util.jIOError) && (error.status_code === 404)) {
+          return context._sub_storage.put({
+            "_id": context._document_key
+          })
+            .push(function () {
+              return context._sub_storage.putAttachment({
+                "_id": context._document_key,
+                "_attachment": doc_id + DOCUMENT_EXTENSION,
+                "_blob": new Blob([JSON.stringify(param)], {type: "application/json"})
+              });
+            });
+        }
+        throw error;
+      })
+      .push(function () {
+        return doc_id;
+      });
+
+  };
+
+  FileSystemBridgeStorage.prototype.remove = function (param) {
+    var context = this,
+      got_error = false,
+      doc_id = param._id;
+    return new RSVP.Queue()
+
+      // First, try to remove enclosure
+      .push(function () {
+        return context._sub_storage.removeAttachment({
+          "_id": ROOT,
+          "_attachment": doc_id
+        });
+      })
+
+      .push(undefined, function (error) {
+        if ((error instanceof jIO.util.jIOError) && (error.status_code === 404)) {
+          got_error = true;
+          return;
+        }
+        throw error;
+      })
+
+      // Second, try to remove explicit doc
+      .push(function () {
+        return context._sub_storage.removeAttachment({
+          "_id": context._document_key,
+          "_attachment": doc_id + DOCUMENT_EXTENSION
+        });
+      })
+
+      .push(undefined, function (error) {
+        if ((!got_error) && (error instanceof jIO.util.jIOError) && (error.status_code === 404)) {
+          return;
+        }
+        throw error;
+      });
+
+  };
+
+  FileSystemBridgeStorage.prototype.hasCapacity = function (capacity) {
+    if (capacity === "list") {
+      return true;
+    }
+    return false;
+  };
+
+  FileSystemBridgeStorage.prototype.buildQuery = function () {
+    var result_dict = {},
+      context = this;
+    return new RSVP.Queue()
+
+      // First, get list of explicit documents
+
+      .push(function () {
+        return context._sub_storage.get({
+          "_id": context._document_key
+        });
+      })
+      .push(function (result) {
+        var key;
+        for (key in result._attachments) {
+          if (result._attachments.hasOwnProperty(key)) {
+            result_dict[key.slice(0, key.length - DOCUMENT_EXTENSION.length)] = null;
+          }
+        }
+      }, function (error) {
+        if ((error instanceof jIO.util.jIOError) && (error.status_code === 404)) {
+          return;
+        }
+        throw error;
+      })
+
+      // Second, get list of enclosure
+
+      .push(function () {
+        return context._sub_storage.get({
+          "_id": ROOT
+        });
+      })
+      .push(function (result) {
+        var key;
+        for (key in result._attachments) {
+          if (result._attachments.hasOwnProperty(key)) {
+            result_dict[key] = null;
+          }
+        }
+      })
+
+      // Finally, build the result
+
+      .push(function () {
+        var result = [],
+          key;
+        for (key in result_dict) {
+          if (result_dict.hasOwnProperty(key)) {
+            result.push({
+              id: key,
+              value: {}
+            });
+          }
+        }
+        return result;
+      });
+
+  };
+
+  FileSystemBridgeStorage.prototype.getAttachment = function (param) {
+    if (param._attachment !== "enclosure") {
+      throw new Error("Only support 'enclosure' attachment");
+    }
+
+    return this._sub_storage.getAttachment({
+      "_id": ROOT,
+      "_attachment": param._id
+    });
+  };
+
+  FileSystemBridgeStorage.prototype.putAttachment = function (param) {
+    if (param._attachment !== "enclosure") {
+      throw new Error("Only support 'enclosure' attachment");
+    }
+
+    return this._sub_storage.putAttachment({
+      "_id": ROOT,
+      "_attachment": param._id,
+      "_blob": param._blob
+    });
+  };
+
+  FileSystemBridgeStorage.prototype.removeAttachment = function (param) {
+    if (param._attachment !== "enclosure") {
+      throw new Error("Only support 'enclosure' attachment");
+    }
+
+    return this._sub_storage.removeAttachment({
+      "_id": ROOT,
+      "_attachment": param._id
+    });
+  };
+
+  jIO.addStorage('drivetojiomapping', FileSystemBridgeStorage);
+
+}(jIO));