feat: Add token metadata API

apps/cic-eth/cic_eth/pytest/mock/__init__.py

@@ -1 +1,2 @@
 from .filter import *
+from .callback import *

apps/cic-eth/cic_eth/pytest/mock/callback.py

@@ -0,0 +1,38 @@
+# standard imports
+import os
+import logging
+import mmap
+
+# standard imports
+import tempfile
+
+# external imports
+import celery
+
+#logg = logging.getLogger(__name__)
+logg = logging.getLogger()
+
+celery_app = celery.current_app
+
+
+class CallbackTask(celery.Task):
+
+    mmap_path = tempfile.mkdtemp()
+
+
+@celery_app.task(bind=True, base=CallbackTask)
+def test_callback(self, a, b, c):
+    s = 'ok'
+    if c > 0:
+        s = 'err'
+
+    fp = os.path.join(self.mmap_path, b)
+    f = open(fp, 'wb+')
+    f.write(b'\x00')
+    f.seek(0)
+    m = mmap.mmap(f.fileno(), length=1)
+    m.write(c.to_bytes(1, 'big'))
+    m.close()
+    f.close()
+
+    logg.debug('test callback ({}): {} {} {}'.format(s, a, b, c))