217 add functionality to send callback messages

doc/source/user_guide/ProgressReporter.ipynb

@@ -0,0 +1,97 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Progress reporting for long running tasks"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "from oda_api.api import ProgressReporter\n",
+    "import time"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Initialise ProgressReporter"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 2,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "pr = ProgressReporter()"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Split your task into subtasks to enable progress report\n",
+    "use ProgressReporter.report_progress method to send progress reports"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 3,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "n_steps = 5\n",
+    "for step in range(n_steps):\n",
+    "    stage = f\"simulation stage {step}\"\n",
+    "    progress = 100 * step // n_steps\n",
+    "    n_substeps = 10\n",
+    "    \n",
+    "    # optionally define subtasks\n",
+    "    for substep in range(n_substeps):\n",
+    "        substage = f\"subtask {substep}\"\n",
+    "        subtask_progress = 100 * substep // n_substeps\n",
+    "\n",
+    "        time.sleep(0.001) # replace this by actual calculation\n",
+    "\n",
+    "        # report progress, optionally adding extra message\n",
+    "        message='some message'\n",
+    "        \n",
+    "        pr.report_progress(stage=stage, progress=progress, substage=substage, subprogress=subtask_progress, message=message)"
+   ]
+  }
+ ],
+ "metadata": {
+  "kernel_info": {
+   "name": "python2"
+  },
+  "kernelspec": {
+   "display_name": "Python 3 (ipykernel)",
+   "language": "python",
+   "name": "python3"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
+   "version": "3.9.18"
+  },
+  "nteract": {
+   "version": "0.15.0"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 4
+}

doc/source/user_guide/tutorial_main.rst

@@ -25,6 +25,8 @@ The following tutorial covers a large fraction of the code features. The example
 
    Upload a product to the Product Gallery <UploadToGallery.ipynb>
 
+   Progress reporting for long running tasks <ProgressReporter.ipynb>
+
    Examples of workflows <https://github.com/cdcihub/oda_api_benchmark>
 
 

oda_api/api.py

@@ -36,6 +36,7 @@
 import requests
 import ast
 import json
+import re
 
 try:
     # compatibility in some remaining environments
@@ -1339,3 +1340,49 @@
                 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, stage: str=None, progress: int=50, substage: str=None, subprogress: int=None, message:str=None):
+        """
+        Report progress via callback URL
+        :param stage: current stage description string
+        :param progress: current stage progress in %
+        :param substage: current substage description string
+        :param subprogress: current substage progress in %
+        :param message: message to pass
+        """
+        callback_payload = dict(stage=stage, progress=progress, substage=substage, subprogress=subprogress, message=message)
+        callback_payload = {k: v for k, v in callback_payload.items() if v is not None}
+        callback_payload['action'] = 'progress'
+        if not self.enabled:
+            logger.info('no callback registered, skipping')
+            return
+
+        logger.info('will perform callback: %s', self._callback)
+
+        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

tests/test_progress_report.py

@@ -0,0 +1,41 @@
+from oda_api.api import ProgressReporter
+import os
+import json
+
+callback_file = ".oda_api_callback"
+request_params = dict(stage='simulation', progress=50, substage='spectra', subprogress=30, message='some message')
+
+def test_progress_reporter_disabled():
+    if os.path.isfile(callback_file):
+        os.remove(callback_file)
+    # if callback is not available
+    pr = ProgressReporter()
+    assert not pr.enabled
+    # the call below should not produce exception
+    try:
+        pr.report_progress(**request_params)
+    except:
+        assert False, 'report_progress raises exception in case of disabled ProgressReporter'
+
+def test_progress_reporter_enabled():
+    # if callback is available
+    try:
+        dump_file = 'callback'
+        with open(callback_file, 'w') as file:
+            print(f'file://{os.getcwd()}/{dump_file}', file=file)
+
+        pr = ProgressReporter()
+        assert pr.enabled
+
+        pr.report_progress(**request_params)
+
+        # verify that params passed to report_progress were saved to dump_file
+        with open(dump_file) as json_file:
+            saved_params = json.load(json_file)
+            assert saved_params == request_params
+    finally:
+        if os.path.isfile(callback_file):
+            os.remove(callback_file)
+        if os.path.isfile(dump_file):
+            os.remove(dump_file)
+