Timeseries to table transformation: Improve time series detection (#77841)

* Improve time series detection

* Prettier

* Add test

* Update packages/grafana-data/src/dataframe/utils.ts

Co-authored-by: Jev Forsberg <46619047+baldm0mma@users.noreply.github.com>

* Ensure correct time field support and set maximum size

* Look at each field to see if they are time series

* Add further tests

* Prettier

---------

Co-authored-by: Jev Forsberg <46619047+baldm0mma@users.noreply.github.com>

packages/grafana-data/src/dataframe/index.ts

@@ -7,5 +7,5 @@ export * from './dimensions';
 export * from './ArrayDataFrame';
 export * from './DataFrameJSON';
 export * from './frameComparisons';
-export { anySeriesWithTimeField, isTimeSeriesFrame, isTimeSeriesFrames } from './utils';
+export { anySeriesWithTimeField, isTimeSeriesFrame, isTimeSeriesFrames, isTimeSeriesField } from './utils';
 export { StreamingDataFrame, StreamingFrameAction, type StreamingFrameOptions, closestIdx } from './StreamingDataFrame';

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

@@ -1,24 +1,70 @@
-import { DataFrame, FieldType } from '../types/dataFrame';
+import { DataFrame, Field, FieldType } from '../types/dataFrame';
 
 import { getTimeField } from './processDataFrame';
 
+const MAX_TIME_COMPARISONS = 100;
+
 export function isTimeSeriesFrame(frame: DataFrame) {
   // If we have less than two frames we can't have a timeseries
   if (frame.fields.length < 2) {
     return false;
   }
 
-  // In order to have a time series we need a time field
-  // and at least one number field
-  const timeField = frame.fields.find((field) => field.type === FieldType.time);
+  // Find a number field, as long as we have any number field this should work
   const numberField = frame.fields.find((field) => field.type === FieldType.number);
-  return timeField !== undefined && numberField !== undefined;
+
+  // There are certain query types in which we will
+  // get times but they will be the same or not be
+  // in increasing order. To have a time-series the
+  // times need to be ordered from past to present
+  let timeFieldFound = false;
+  for (const field of frame.fields) {
+    if (isTimeSeriesField(field)) {
+      timeFieldFound = true;
+      break;
+    }
+  }
+
+  return timeFieldFound && numberField !== undefined;
 }
 
 export function isTimeSeriesFrames(data: DataFrame[]) {
   return !data.find((frame) => !isTimeSeriesFrame(frame));
 }
 
+/**
+ * Determines if a field is a time field in ascending
+ * order within the sampling range specified by
+ * MAX_TIME_COMPARISONS
+ *
+ * @param field
+ * @returns boolean
+ */
+export function isTimeSeriesField(field: Field) {
+  if (field.type !== FieldType.time) {
+    return false;
+  }
+
+  let greatestTime: number | null = null;
+  let testWindow = field.values.length > MAX_TIME_COMPARISONS ? MAX_TIME_COMPARISONS : field.values.length;
+
+  // Test up to the test window number of values
+  for (let i = 0; i < testWindow; i++) {
+    const time = field.values[i];
+
+    // Check to see if the current time is greater than
+    // the last time. If we get to the end then we
+    // have a time series otherwise we return false
+    if (greatestTime === null || (time !== null && time > greatestTime)) {
+      greatestTime = time;
+    } else {
+      return false;
+    }
+  }
+
+  return true;
+}
+
 /**
  * Indicates if there is any time field in the array of data frames
  * @param data