[gnome-maps] Add wrapper module for the Overpass API

[Jonas Danielsson <jonasdn src gnome org>]

commit 3da582bcea2f57647d48ed5dd49dcf14665ddd0f
Author: rishirajsinghjhelumi <rishiakhnoor gmail com>
Date:   Tue Sep 2 02:27:17 2014 +0530

    Add wrapper module for the Overpass API
    
    Overpass QL: http://wiki.openstreetmap.org/wiki/Overpass_API/Overpass_QL
    
    https://bugzilla.gnome.org/show_bug.cgi?id=726625

 src/gnome-maps.js.gresource.xml |    1 +
 src/overpass.js                 |  136 +++++++++++++++++++++++++++++++++++++++
 2 files changed, 137 insertions(+), 0 deletions(-)
---
diff --git a/src/gnome-maps.js.gresource.xml b/src/gnome-maps.js.gresource.xml
index e1fca53..1b3c13b 100644
--- a/src/gnome-maps.js.gresource.xml
+++ b/src/gnome-maps.js.gresource.xml
@@ -17,6 +17,7 @@
     <file>mapWalker.js</file>
     <file>notification.js</file>
     <file>notificationManager.js</file>
+    <file>overpass.js</file>
     <file>path.js</file>
     <file>place.js</file>
     <file>placeEntry.js</file>
diff --git a/src/overpass.js b/src/overpass.js
new file mode 100644
index 0000000..9864613
--- /dev/null
+++ b/src/overpass.js
@@ -0,0 +1,136 @@
+/* -*- Mode: JS2; indent-tabs-mode: nil; js2-basic-offset: 4 -*- */
+/* vim: set et ts=4 sw=4: */
+/*
+ * GNOME Maps 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 2 of the License, or (at your
+ * option) any later version.
+ *
+ * GNOME Maps 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 GNOME Maps; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ * Author: Rishi Raj Singh Jhelumi <rishiraj devel gmail com>
+ */
+
+const Format = imports.format;
+const Geocode = imports.gi.GeocodeGlib;
+const Lang = imports.lang;
+const Soup = imports.gi.Soup;
+
+const Place = imports.place;
+
+const _DEFAULT_TIMEOUT = 180;
+const _DEFAULT_MAXSIZE = 536870912;
+const _DEFAULT_OUTPUT_FORMAT = 'json';
+const _DEFAULT_OUTPUT_COUNT = 1e6;
+const _DEFAULT_OUTPUT_INFO = 'body';
+const _DEFAULT_OUTPUT_SORT_ORDER = 'qt';
+
+const BASE_URL = 'http://overpass-api.de/api/interpreter';
+
+const Overpass = new Lang.Class({
+    Name: 'Overpass',
+
+    _init: function(params) {
+        params = params || { };
+
+        // maximum allowed runtime for the query in seconds
+        this.timeout = params.timeout || _DEFAULT_TIMEOUT;
+
+        //  maximum allowed memory for the query in bytes RAM on the server
+        this.maxsize = params.maxsize || _DEFAULT_MAXSIZE;
+
+        // output format : json or xml
+        this.outputFormat = params.outputFormat || _DEFAULT_OUTPUT_FORMAT;
+
+        // maximum number of results the output must contain
+        this.outputCount = params.outputCount || _DEFAULT_OUTPUT_COUNT;
+
+        // data output info must contain : ids, skel, body, meta
+        this.outputInfo = params.outputInfo || _DEFAULT_OUTPUT_INFO;
+
+        // data sort order : qt(fastest based on geography), ids, asc
+        this.outputSortOrder = params.outputSortOrder || _DEFAULT_OUTPUT_SORT_ORDER;
+
+        // HTTP Session Variables
+        this._session = new Soup.Session();
+    },
+
+    addInfo: function(place, callback) {
+        let url = this._getQueryUrl(place.osm_id);
+        let uri = new Soup.URI(url);
+        let request = new Soup.Message({ method: 'GET',
+                                         uri: uri });
+
+        this._session.queue_message(request, (function(obj, message) {
+            if (message.status_code !== Soup.KnownStatusCode.OK) {
+                callback(false, message.status_code, null);
+                return;
+            }
+            try {
+                let jsonObj = JSON.parse(message.response_body.data);
+                callback(true,
+                         message.status_code,
+                         this._createPlace(place, jsonObj));
+            } catch(e) {
+                callback(false, message.status_code, null);
+            }
+        }).bind(this));
+    },
+
+    _createPlace: function(place, overpassData) {
+        let element = overpassData.elements[0];
+        let newPlace = new Place.Place({ place: place });
+
+        if (!(element && element.tags && element.tags.name))
+            return newPlace;
+
+        if (element.tags.name)
+            newPlace.name = element.tags.name;
+        if (element.tags.population)
+            newPlace.population = element.tags.population;
+        if (element.tags.wikipedia)
+            newPlace.wiki = element.tags.wikipedia;
+        if (element.tags.wheelchair)
+            newPlace.wheelchair = element.tags.wheelchair;
+        if (element.tags.opening_hours)
+            newPlace.openingHours = element.tags.opening_hours;
+
+        return newPlace;
+    },
+
+    _getQueryUrl: function(osmId) {
+        return Format.vprintf('%s?data=%s', [ BASE_URL,
+                                              this._generateOverpassQuery(osmId) ]);
+    },
+
+    _generateOverpassQuery: function(osmId) {
+        return Format.vprintf('%s%s%s;%s;%s;',
+                              [ this._getKeyValue('timeout', this.timeout),
+                                this._getKeyValue('out', this.outputFormat),
+                                this._getKeyValue('maxsize', this.maxsize),
+                                this._getData(osmId),
+                                this._getOutput() ]);
+    },
+
+    _getKeyValue: function(key, value) {
+        return Format.vprintf('[%s:%s]', [ key,
+                                           value ]);
+    },
+
+    _getData: function(osmId) {
+        return Format.vprintf('node(%s)', [osmId]);
+    },
+
+    _getOutput: function() {
+        return Format.vprintf('out %s %s %s', [ this.outputInfo,
+                                                this.outputSortOrder,
+                                                this.outputCount ]);
+    }
+});