From 6af4ebed2bd121963042faca7629f1211c0418d3 Mon Sep 17 00:00:00 2001
From: Oleg Kalashev <oleg.kalashev@gmail.com>
Date: Mon, 6 Nov 2023 16:20:00 +0300
Subject: [PATCH] ProgressReporter class added

---
 oda_api/api.py | 44 ++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 44 insertions(+)

diff --git a/oda_api/api.py b/oda_api/api.py
index f5b5d6d6..1faa0d26 100644
--- a/oda_api/api.py
+++ b/oda_api/api.py
@@ -36,6 +36,7 @@
 import requests
 import ast
 import json
+import re
 
 try:
     # compatibility in some remaining environments
@@ -1339,3 +1340,46 @@ def from_response_json(cls, res_json, instrument, product):
                 p.meta_data = p.meta
 
         return d
+
+class ProgressReporter(object):
+    """
+    The class allows to report task progress to end user
+    """
+    def __init__(self):
+        self._callback = None
+        callback_file = ".oda_api_callback"  # perhaps it would be better to define this constant in a common lib
+        if not os.path.isfile(callback_file):
+            return
+        with open(callback_file, 'r') as file:
+            self._callback = file.read().strip()
+
+    @property
+    def enabled(self):
+        return self._callback is not None
+
+    def report_progress(self, message: str):
+        """
+        Report progress via callback URL
+        :param message: message to pass
+        """
+        if not self.enabled:
+            logger.info('no callback registered, skipping')
+            return
+
+        logger.info('will perform callback: %s', self._callback)
+
+        callback_payload = dict(
+            message=message
+        )
+
+        if re.match('^file://', self._callback):
+            with open(self._callback.replace('file://', ''), "w") as f:
+                json.dump(callback_payload, f)
+            logger.info('stored callback in a file %s', self._callback)
+
+        elif re.match('^https?://', self._callback):
+            r = requests.get(self._callback, params=callback_payload)
+            logger.info('callback %s returns %s : %s', self._callback, r, r.text)
+
+        else:
+            raise NotImplementedError