Correctly handle config python strings and add short URL example with function

Author: typpo

examples/short_url_example_with_function.py

@@ -0,0 +1,34 @@
+from quickchart import QuickChart
+
+qc = QuickChart()
+qc.config = '''{
+  type: 'bar',
+  data: {
+    labels: ['Q1', 'Q2', 'Q3', 'Q4'],
+    datasets: [{
+      label: 'Users',
+      data: [50, 60, 70, 180]
+    }, {
+      label: 'Revenue',
+      data: [100, 200, 300, 400]
+    }]
+  },
+  options: {
+    scales: {
+      yAxes: [{
+        ticks: {
+          callback: (val) => {
+            return val + 'k';
+          }
+        }
+      }]
+    }
+  }
+}'''
+
+print(qc.get_short_url())
+#
+# Example output (note that this shortened URL is now expired and will not display a chart):
+#
+# https://quickchart.io/chart/render/f-b4bf9221-0499-4bc6-b1ae-6f7c78be9d93
+#

quickchart.py

@@ -25,7 +25,7 @@ def get_url(self):
         if not self.is_valid():
             raise RuntimeError('You must set the `config` attribute before generating a url')
         params = {
-            'c': json.dumps(self.config),
+            'c': json.dumps(self.config) if type(self.config) == dict else self.config,
             'w': self.width,
             'h': self.height,
             'bkg': self.background_color,
@@ -43,7 +43,7 @@ def get_short_url(self):
             raise RuntimeError('Could not find `requests` dependency')
 
         postdata = {
-            'chart': json.dumps(self.config),
+            'chart': json.dumps(self.config) if type(self.config) == dict else self.config,
             'width': self.width,
             'height': self.height,
             'backgroundColor': self.background_color,