JSONP - Attempt to strip out JSONP

changedetectionio/html_tools.py

@@ -487,13 +487,25 @@ def extract_json_as_string(content, json_filter, ensure_is_ldjson_info_type=None
         except json.JSONDecodeError as e:
             logger.warning(f"Error processing JSON {content[:20]}...{str(e)})")
     else:
-        # Probably something else, go fish inside for it
-        try:
-            stripped_text_from_html = extract_json_blob_from_html(content=content,
-                                                                  ensure_is_ldjson_info_type=ensure_is_ldjson_info_type,
-                                                                  json_filter=json_filter                                                                  )
-        except json.JSONDecodeError as e:
-            logger.warning(f"Error processing JSON while extracting JSON from HTML blob {content[:20]}...{str(e)})")
+        # Check for JSONP wrapper: someCallback({...}) or some.namespace({...})
+        # Server may claim application/json but actually return JSONP
+        jsonp_match = re.match(r'^\w[\w.]*\s*\((.+)\)\s*;?\s*$', content.lstrip("\ufeff").strip(), re.DOTALL)
+        if jsonp_match:
+            try:
+                inner = jsonp_match.group(1).strip()
+                logger.warning(f"Content looks like JSONP, attempting to extract inner JSON for filter '{json_filter}'")
+                stripped_text_from_html = _parse_json(json.loads(inner), json_filter)
+            except json.JSONDecodeError as e:
+                logger.warning(f"Error processing JSONP inner content {content[:20]}...{str(e)})")
+
+        if not stripped_text_from_html:
+            # Probably something else, go fish inside for it
+            try:
+                stripped_text_from_html = extract_json_blob_from_html(content=content,
+                                                                      ensure_is_ldjson_info_type=ensure_is_ldjson_info_type,
+                                                                      json_filter=json_filter)
+            except json.JSONDecodeError as e:
+                logger.warning(f"Error processing JSON while extracting JSON from HTML blob {content[:20]}...{str(e)})")
 
     if not stripped_text_from_html:
         # Re 265 - Just return an empty string when filter not found

changedetectionio/processors/magic.py

@@ -100,7 +100,13 @@ class guess_stream_type():
         if any(s in http_content_header for s in RSS_XML_CONTENT_TYPES):
             self.is_rss = True
         elif any(s in http_content_header for s in JSON_CONTENT_TYPES):
-            self.is_json = True
+            # JSONP detection: server claims application/json but content is actually JSONP (e.g. cb({...}))
+            # A JSONP response starts with an identifier followed by '(' - not valid JSON
+            if re.match(r'^\w[\w.]*\s*\(', test_content):
+                logger.warning(f"Content-Type header claims JSON but content looks like JSONP (starts with identifier+parenthesis) - treating as plaintext")
+                self.is_plaintext = True
+            else:
+                self.is_json = True
         elif 'pdf' in magic_content_header:
             self.is_pdf = True
         # magic will call a rss document 'xml'

changedetectionio/tests/test_jsonpath_jq_selector.py

@@ -16,6 +16,51 @@ except ModuleNotFoundError:
 
 
 
+def test_jsonp_treated_as_plaintext():
+    from ..processors.magic import guess_stream_type
+
+    # JSONP content (server wrongly claims application/json) should be detected as plaintext
+    # Callback names are arbitrary identifiers, not always 'cb'
+    jsonp_content = 'jQuery123456({ "version": "8.0.41", "url": "https://example.com/app.apk" })'
+    result = guess_stream_type(http_content_header="application/json", content=jsonp_content)
+    assert result.is_json is False
+    assert result.is_plaintext is True
+
+    # Variation with dotted callback name e.g. jQuery.cb(...)
+    jsonp_dotted = 'some.callback({ "version": "1.0" })'
+    result = guess_stream_type(http_content_header="application/json", content=jsonp_dotted)
+    assert result.is_json is False
+    assert result.is_plaintext is True
+
+    # Real JSON should still be detected as JSON
+    json_content = '{ "version": "8.0.41", "url": "https://example.com/app.apk" }'
+    result = guess_stream_type(http_content_header="application/json", content=json_content)
+    assert result.is_json is True
+    assert result.is_plaintext is False
+
+
+def test_jsonp_json_filter_extraction():
+    from .. import html_tools
+
+    # Tough case: dotted namespace callback, trailing semicolon, deeply nested content with arrays
+    jsonp_content = 'weixin.update.callback({"platforms": {"android": {"variants": [{"arch": "arm64", "versionName": "8.0.68", "url": "https://example.com/app-arm64.apk"}, {"arch": "arm32", "versionName": "8.0.41", "url": "https://example.com/app-arm32.apk"}]}}});'
+
+    # Deep nested jsonpath filter into array element
+    text = html_tools.extract_json_as_string(jsonp_content, "json:$.platforms.android.variants[0].versionName")
+    assert text == '"8.0.68"'
+
+    # Filter that selects the second array element
+    text = html_tools.extract_json_as_string(jsonp_content, "json:$.platforms.android.variants[1].arch")
+    assert text == '"arm32"'
+
+    if jq_support:
+        text = html_tools.extract_json_as_string(jsonp_content, "jq:.platforms.android.variants[0].versionName")
+        assert text == '"8.0.68"'
+
+        text = html_tools.extract_json_as_string(jsonp_content, "jqraw:.platforms.android.variants[1].url")
+        assert text == "https://example.com/app-arm32.apk"
+
+
 def test_unittest_inline_html_extract():
     # So lets pretend that the JSON we want is inside some HTML
     content="""