Handle date formatting specifically for Excel (#13133)

Excel will not parse an ISO8601 date, so add a new version of
FormatValue specifically made for Excel.

The Docjure library used has formatting helpers for a few Java classes,
but specifically java.util.Date and not the newer Java 8 Time classes.
In this case, it formats any java.util.Date as m/d/yy.

Resolves #10803

src/metabase/query_processor/streaming/xlsx.clj

@@ -2,14 +2,12 @@
   (:require [cheshire.core :as json]
             [dk.ative.docjure.spreadsheet :as spreadsheet]
             [java-time :as t]
-            [metabase.query-processor.streaming
-             [common :as common]
-             [interface :as i]]
+            [metabase.query-processor.streaming.interface :as i]
             [metabase.util
              [date-2 :as u.date]
              [i18n :refer [tru]]])
   (:import java.io.OutputStream
-           org.apache.poi.ss.usermodel.Cell
+           [org.apache.poi.ss.usermodel Cell CellType]
            org.apache.poi.xssf.streaming.SXSSFWorkbook))
 
 (defmethod i/stream-options :xlsx
@@ -19,12 +17,45 @@
    :headers                   {"Content-Disposition" (format "attachment; filename=\"query_result_%s.xlsx\""
                                                              (u.date/format (t/zoned-date-time)))}})
 
+(defprotocol ExcelFormatValue
+  "Protocol for specifying how objects of various classes in QP result rows should be formatted for Excel
+  exports. The generic version in `common/FormatValue` does not work for Excel due to date/time formats."
+  (excel-format-value [this]
+    "Format this value in a QP result row appropriately for a results download to Excel."))
+
+;; this version of the protocol resolves #10803 by not converting datetimes to ISO8601 (which Excel cannot parse)
+;; Docjure can handle java.util.Date instances, but not the new Java 8 Time instances, so we convert everything
+;; to java.util.Date.
+(extend-protocol ExcelFormatValue
+  nil
+  (excel-format-value [_] nil)
+
+  Object
+  (excel-format-value [this] this)
+
+  java.time.temporal.Temporal
+  (excel-format-value [this]
+    (t/java-date this))
+
+  java.time.LocalDateTime
+  (excel-format-value [this]
+    ;; this is a sticky one - LocalDateTime where? Using the server's timezone for the conversion.
+    (t/java-date (t/zoned-date-time this (t/zone-id))))
+
+  java.time.OffsetDateTime
+  (excel-format-value [this]
+     (t/java-date this))
+
+  java.time.ZonedDateTime
+  (excel-format-value [this]
+    (t/java-date this)))
+
 ;; add a generic implementation for the method that writes values to XLSX cells that just piggybacks off the
 ;; implementations we've already defined for encoding things as JSON. These implementations live in
 ;; `metabase.middleware`.
 (defmethod spreadsheet/set-cell! Object [^Cell cell, value]
-  (when (= (.getCellType cell) Cell/CELL_TYPE_FORMULA)
-    (.setCellType cell Cell/CELL_TYPE_STRING))
+  (when (= (.getCellType cell) CellType/FORMULA)
+    (.setCellType cell CellType/STRING))
   ;; stick the object in a JSON map and encode it, which will force conversion to a string. Then unparse that JSON and
   ;; use the resulting value as the cell's new String value.  There might be some more efficient way of doing this but
   ;; I'm not sure what it is.
@@ -42,7 +73,7 @@
         (spreadsheet/add-row! sheet (map (some-fn :display_name :name) cols)))
 
       (write-row! [_ row _]
-        (spreadsheet/add-row! sheet (map common/format-value row)))
+        (spreadsheet/add-row! sheet (map excel-format-value row)))
 
       (finish! [_ _]
         (spreadsheet/save-workbook-into-stream! os workbook)