add 'output.num-to-str' option

... to convert any numeric values to string when outputting them as JSON
(during '--dump-json' or otherwise)

gallery_dl/job.py

@@ -498,7 +498,6 @@ def __init__(self, url, parent=None, file=sys.stdout):
         Job.__init__(self, url, parent)
         self.file = file
         self.data = []
-        self.ensure_ascii = config.get(("output", "ascii"), True)
 
     def run(self):
         # collect data
@@ -510,10 +509,15 @@ def run(self):
         except BaseException:
             pass
 
+        if config.get(("output", "num-to-str"), False):
+            for msg in self.data:
+                util.transform_dict(msg[-1], util.number_to_string)
+
         # dump to 'file'
         json.dump(
             self.data, self.file,
-            sort_keys=True, indent=2, ensure_ascii=self.ensure_ascii
+            sort_keys=True, indent=2,
+            ensure_ascii=config.get(("output", "ascii"), True),
         )
         self.file.write("\n")
 
@@ -528,3 +532,6 @@ def handle_directory(self, keywords):
 
     def handle_queue(self, url, keywords):
         self.data.append((Message.Queue, url, keywords.copy()))
+
+    def handle_finalize(self):
+        self.file.close()

gallery_dl/util.py

@@ -57,7 +57,7 @@ def wrap():
 
 
 def combine_dict(a, b):
-    """Recursively combine the contents of b into a"""
+    """Recursively combine the contents of 'b' into 'a'"""
     for key, value in b.items():
         if key in a and isinstance(value, dict) and isinstance(a[key], dict):
             combine_dict(a[key], value)
@@ -66,6 +66,20 @@ def combine_dict(a, b):
     return a
 
 
+def transform_dict(a, func):
+    """Recursively apply 'func' to all values in 'a'"""
+    for key, value in a.items():
+        if isinstance(value, dict):
+            transform_dict(value, func)
+        else:
+            a[key] = func(value)
+
+
+def number_to_string(value):
+    """Convert numbers (int, float) to string; Return everything else as is."""
+    return str(value) if isinstance(value, (int, float)) else value
+
+
 def expand_path(path):
     """Expand environment variables and tildes (~)"""
     if not path: