used bytesIO deal with qrcode

myems-api/core/meter.py

@@ -1,4 +1,5 @@
 import base64
+import io
 import os
 
 import falcon
@@ -10,6 +11,7 @@ import qrcode
 import qrcode.image.svg
 
 from core.useractivity import user_logger, access_control
+from core.utilities import qrcode_to_base64
 
 
 class MeterCollection:
@@ -86,22 +88,7 @@ class MeterCollection:
         result = list()
         if rows_meters is not None and len(rows_meters) > 0:
             for row in rows_meters:
-                file_path = os.path.join(config.upload_path, row['uuid'] + ".svg")
+                meter_qrcode = qrcode_to_base64(data="meter" + row['uuid'])
-                try:
-                    file = open(file_path, "rb")
-                except IOError:
-                    meter_qrcode = qrcode.QRCode(
-                        version=1,
-                        error_correction=qrcode.ERROR_CORRECT_L,
-                        box_size=10,
-                        border=4
-                    )
-                    meter_qrcode.add_data("meter" + row['uuid'])
-                    meter_qrcode.make_image(image_factory=qrcode.image.svg.SvgImage).save(file_path)
-                    file = open(file_path, "rb")
-                finally:
-                    qrcode_base64 = base64.b64encode(file.read())
-                    file.close()
                 energy_category = energy_category_dict.get(row['energy_category_id'], None)
                 cost_center = cost_center_dict.get(row['cost_center_id'], None)
                 energy_item = energy_item_dict.get(row['energy_item_id'], None)
@@ -117,7 +104,7 @@ class MeterCollection:
                                "energy_item": energy_item,
                                "master_meter": master_meter,
                                "description": row['description'],
-                               "qrcode": qrcode_base64}
+                               "qrcode": meter_qrcode}
                 result.append(meta_result)
 
         cursor.close()
@@ -376,22 +363,7 @@ class MeterItem:
             raise falcon.HTTPError(falcon.HTTP_404, title='API.NOT_FOUND',
                                    description='API.METER_NOT_FOUND')
         else:
-            file_path = os.path.join(config.upload_path, row['uuid'] + ".svg")
+            meter_qrcode = qrcode_to_base64(data="meter"+row['uuid'])
-            try:
-                file = open(file_path, "rb")
-            except IOError:
-                meter_qrcode = qrcode.QRCode(
-                    version=1,
-                    error_correction=qrcode.ERROR_CORRECT_L,
-                    box_size=10,
-                    border=4
-                )
-                meter_qrcode.add_data("meter" + row['uuid'])
-                meter_qrcode.make_image(image_factory=qrcode.image.svg.SvgImage).save(file_path)
-                file = open(file_path, "rb")
-            finally:
-                qrcode_base64 = base64.b64encode(file.read())
-                file.close()
             energy_category = energy_category_dict.get(row['energy_category_id'], None)
             cost_center = cost_center_dict.get(row['cost_center_id'], None)
             energy_item = energy_item_dict.get(row['energy_item_id'], None)
@@ -407,7 +379,7 @@ class MeterItem:
                            "energy_item": energy_item,
                            "master_meter": master_meter,
                            "description": row['description'],
-                           "qrcode": qrcode_base64}
+                           "qrcode": meter_qrcode}
 
         resp.text = json.dumps(meta_result)
 

myems-api/core/utilities.py

@@ -1,8 +1,13 @@
+import base64
 import calendar
+import io
 from datetime import datetime, timedelta
 import mysql.connector
 import collections
 from decimal import Decimal
+import qrcode.image.svg
+import qrcode
+
 import config
 import statistics
 
@@ -248,7 +253,7 @@ def get_energy_category_tariffs(cost_center_id, energy_category_id, start_dateti
         query_timeofuse_tariffs = (" SELECT tariff_id, start_time_of_day, end_time_of_day, price "
                                    " FROM tbl_tariffs_timeofuses "
                                    " WHERE tariff_id IN ( " + ', '.join(map(str, tariff_dict.keys())) + ")"
-                                   " ORDER BY tariff_id, start_time_of_day ")
+                                                                                                        " ORDER BY tariff_id, start_time_of_day ")
         cursor.execute(query_timeofuse_tariffs, )
         rows_timeofuse_tariffs = cursor.fetchall()
     except Exception as e:
@@ -352,7 +357,7 @@ def get_energy_category_peak_types(cost_center_id, energy_category_id, start_dat
         query_timeofuse_tariffs = (" SELECT tariff_id, start_time_of_day, end_time_of_day, peak_type "
                                    " FROM tbl_tariffs_timeofuses "
                                    " WHERE tariff_id IN ( " + ', '.join(map(str, tariff_dict.keys())) + ")"
-                                   " ORDER BY tariff_id, start_time_of_day ")
+                                                                                                        " ORDER BY tariff_id, start_time_of_day ")
         cursor.execute(query_timeofuse_tariffs, )
         rows_timeofuse_tariffs = cursor.fetchall()
     except Exception as e:
@@ -1001,3 +1006,23 @@ def statistics_hourly_data_by_period(rows_hourly, start_datetime_utc, end_dateti
             variance = statistics.variance(sample_data)
 
         return result_rows_yearly, mean, median, minimum, maximum, stdev, variance
+
+
+def qrcode_to_base64(version=1, error_correction=qrcode.ERROR_CORRECT_L, box_size=10, border=4,
+                     factory=qrcode.image.svg.SvgImage, data=None):
+    if version < 1 or version > 40 or \
+            box_size < 0 or border < 0 or \
+            error_correction not in \
+            (qrcode.ERROR_CORRECT_L, qrcode.ERROR_CORRECT_M, qrcode.ERROR_CORRECT_H, qrcode.ERROR_CORRECT_Q):
+        return " "
+    qr = qrcode.QRCode(
+        version=1,
+        error_correction=qrcode.ERROR_CORRECT_L,
+        box_size=10,
+        border=4,
+    )
+    qr.add_data(data)
+    img = qr.make_image(image_factory=factory)
+    f = io.BytesIO()
+    img.save(f)
+    return base64.b64encode(f.getvalue())