Added /export route

influxgraph.py

@@ -3,6 +3,7 @@ import time
 import logging
 from colors import assign_colors_to_curves
 import json
+import io
 
 class InfluxGraph:
     """
@@ -162,6 +163,27 @@ class InfluxGraph:
             self.livemode = self.LIVE
             return dict(type='accept-graph', live=True)
 
+    def w_export(self, variables, time, interval):
+        """
+        Returns the bytes of a dataframe with the curves given by variables in the time range "time"
+        Called when the route /export is reached.
+
+        Parameters :
+            variables (str) : a comma separataed value string of variable names (influx names) to retrieve
+            time (str) : a commma separated value string (range) of seconds.
+            interval (str) : the interval (resolution) of the values to get (string in seconds)
+
+        Returns :
+            io.BytesIO : an BytesIO object containing the dataframe to retrieve
+        """
+        df = self.influx_data_getter.get_curves_data_frame(variables, time, interval)
+
+        mem = io.BytesIO()
+        mem.write(bytes(df.to_csv(sep="\t", index=False), "utf-8"))
+        mem.seek(0)
+
+        return mem
+
     def graphpoll(self):
         """
         Polls the last known values for all the available variables, and returns only those whose polled value is more recent than the nost recent displayed one.

seaweb.py

@@ -120,6 +120,32 @@ def show_clients():
         result += c.remote_info + " " + "; ".join(c.info()) + "<br>"
     return result
 
+@app.route('/export')
+def export():
+    args = flask.request.args
+    kwargs = dict((k, args.get(k)) for k in args)
+    path = flask.request.path
+    logging.info('GET %s %s', path, repr(kwargs))
+    try:
+        id = kwargs.pop('id')
+        client = instrument.clients[id]
+        bytes = client.w_export(**kwargs)
+        
+        return flask.send_file(
+            bytes,
+            as_attachment=True,
+            download_name='export.tsv',
+            mimetype='text/tab-separated-values'
+        )   
+
+    except Exception as e:
+        logging.error('%s', traceback.format_exc())
+        circularlog.log()
+        msg = dict(type='error', request=path[1:], error=repr(e))
+        resp = flask.Response(json.dumps(msg), mimetype='application/json')
+        resp.headers['Access-Control-Allow-Origin'] = '*'
+        return resp
+
 @app.route('/getblock')
 @app.route('/updateblock')
 @app.route('/sendcommand')