[v10.0.x] PanelInspect: Download CSV without extra blank rows (#71290)

PanelInspect: Download CSV without extra blank rows (#71248)

(cherry picked from commit 8a6c6c3285)

Co-authored-by: Juan Cabanas <juan.cabanas@grafana.com>

packages/grafana-data/src/utils/csv.test.ts

@@ -104,9 +104,7 @@ describe('write csv', () => {
       "sep=,
       "Time","Value"
       1598784913123,1234
-      1598784914123,5678
-
-      "
+      1598784914123,5678"
     `);
   });
 });
@@ -131,9 +129,7 @@ describe('DataFrame to CSV', () => {
     const csv = toCSV([dataFrame]);
     expect(csv).toMatchInlineSnapshot(`
       ""Time","{label1=""value1"", label2=""value1""}"
-      1589455688623,1234
-
-      "
+      1589455688623,1234"
     `);
   });
 
@@ -160,9 +156,7 @@ describe('DataFrame to CSV', () => {
     const csv = toCSV([dataFrame]);
     expect(csv).toMatchInlineSnapshot(`
       ""Time","Value"
-      1589455688623,2020-05-14 11:28:08
-
-      "
+      1589455688623,2020-05-14 11:28:08"
     `);
   });
 });

packages/grafana-data/src/utils/csv.ts

@@ -273,7 +273,8 @@ export function toCSV(data: DataFrame[], config?: CSVConfig): string {
   });
   let csv = config.useExcelHeader ? `sep=${config.delimiter}${config.newline}` : '';
 
-  for (const series of data) {
+  for (let s = 0; s < data.length; s++) {
+    const series = data[s];
     const { fields } = series;
 
     // ignore frames with no fields
@@ -313,10 +314,16 @@ export function toCSV(data: DataFrame[], config?: CSVConfig): string {
             csv = csv + writers[j](v);
           }
         }
-        csv = csv + config.newline;
+
+        if (i !== length - 1) {
+          csv = csv + config.newline;
+        }
       }
     }
-    csv = csv + config.newline;
+
+    if (s !== data.length - 1) {
+      csv = csv + config.newline;
+    }
   }
 
   return csv;

public/app/features/inspector/utils/download.test.ts

@@ -37,7 +37,7 @@ describe('inspector download', () => {
       },
     };
 
-    it.each([[dataFrameFromJSON(json), 'test', '"time","name","value"\r\n100,a,1\r\n\r\n']])(
+    it.each([[dataFrameFromJSON(json), 'test', '"time","name","value"\r\n100,a,1']])(
       'should, when logsModel is %s and title is %s, resolve in %s',
       async (dataFrame, title, expected) => {
         downloadDataFrameAsCsv(dataFrame, title);