Add the ability to get the calibre field 'size' using a formatter function booksize()

src/calibre/library/database2.py

@@ -853,6 +853,7 @@ class LibraryDatabase2(LibraryDatabase, SchemaUpgrade, CustomColumns):
         mi.pubdate     = row[fm['pubdate']]
         mi.uuid        = row[fm['uuid']]
         mi.title_sort  = row[fm['sort']]
+        mi.book_size   = row[fm['size']]
         mi.last_modified = row[fm['last_modified']]
         formats = row[fm['formats']]
         if not formats:

src/calibre/manual/template_lang.rst

@@ -230,6 +230,7 @@ The following functions are available in addition to those described in single-f
 
     * ``add(x, y)`` -- returns x + y. Throws an exception if either x or y are not numbers.
     * ``assign(id, val)`` -- assigns val to id, then returns val. id must be an identifier, not an expression
+    * ``booksize()`` -- returns the value of the |app| 'size' field. Returns '' if there are no formats.
     * ``cmp(x, y, lt, eq, gt)`` -- compares x and y after converting both to numbers. Returns ``lt`` if x < y. Returns ``eq`` if x == y. Otherwise returns ``gt``.
     * ``divide(x, y)`` -- returns x / y. Throws an exception if either x or y are not numbers.
     * ``field(name)`` -- returns the metadata field named by ``name``.

src/calibre/utils/formatter_functions.py

@@ -549,8 +549,22 @@ class BuiltinCapitalize(BuiltinFormatterFunction):
     def evaluate(self, formatter, kwargs, mi, locals, val):
         return capitalize(val)
 
+class BuiltinBooksize(BuiltinFormatterFunction):
+    name = 'booksize'
+    arg_count = 0
+    doc = _('booksize() -- return value of the field capitalized')
+
+    def evaluate(self, formatter, kwargs, mi, locals):
+        if mi.book_size is not None:
+            try:
+                return str(mi.book_size)
+            except:
+                pass
+        return ''
+
 builtin_add         = BuiltinAdd()
 builtin_assign      = BuiltinAssign()
+builtin_booksize    = BuiltinBooksize()
 builtin_capitalize  = BuiltinCapitalize()
 builtin_cmp         = BuiltinCmp()
 builtin_contains    = BuiltinContains()