[MRG] Add self version check

conrad/__main__.py

@@ -1,6 +1,6 @@
 # -*- coding: utf-8 -*-
 
-from __future__ import absolute_import
+from .utils import conrad_self_version_check
 
 
 __all__ = ("main",)
@@ -9,6 +9,7 @@
 def main():
     from conrad.cli import cli
 
+    conrad_self_version_check()
     cli()
 
 

conrad/utils.py

@@ -1,11 +1,107 @@
 # -*- coding: utf-8 -*-
 
-from .db import engine
-
+import os
+import sys
+import json
+import logging
+import datetime as dt
+from setuptools.version import pkg_resources
+
+import requests
 import geopy.exc as geopyexceptions
 from geopy.geocoders import Nominatim
 from geopy.extra.rate_limiter import RateLimiter
 
+from .db import engine
+from . import __version__, CONRAD_HOME
+
+
+SELFCHECK_DATE_FMT = "%Y-%m-%dT%H:%M:%SZ"
+
+
+logger = logging.getLogger(__name__)
+
+
+# https://github.com/pypa/pip/blob/master/src/pip/_internal/self_outdated_check.py
+class SelfCheckState(object):
+    def __init__(self, cache_dir):
+        self.state = {}
+        self.statefile_path = os.path.join(cache_dir, "selfcheck.json")
+
+        # Try to load the existing state
+        try:
+            with open(self.statefile_path, "r") as f:
+                self.state = json.load(f)
+        except (IOError, ValueError, KeyError, FileNotFoundError):
+            # Explicitly suppressing exceptions, since we don't want to
+            # error out if the cache file is invalid.
+            pass
+
+    def save(self, pypi_version, current_time):
+        # If we do not have a path to cache in, don't bother saving.
+        if not self.statefile_path:
+            return
+
+        state = {
+            "last_check": current_time.strftime(SELFCHECK_DATE_FMT),
+            "pypi_version": pypi_version,
+        }
+
+        text = json.dumps(state, sort_keys=True, separators=(",", ":"))
+
+        with open(self.statefile_path, "w") as f:
+            f.write(text)
+
+
+def get_pypi_version():
+    url = "https://pypi.org/pypi/conference-radar/json"
+    response = requests.get(url)
+    if response:
+        data = response.json()
+        pypi_version = data["info"]["version"]
+        return pypi_version
+
+
+def conrad_self_version_check():
+    pypi_version = None
+
+    try:
+        state = SelfCheckState(cache_dir=CONRAD_HOME)
+
+        current_time = dt.datetime.utcnow()
+        # Determine if we need to refresh the state
+        if "last_check" in state.state and "pypi_version" in state.state:
+            last_check = dt.datetime.strptime(
+                state.state["last_check"],
+                SELFCHECK_DATE_FMT
+            )
+            if (current_time - last_check).total_seconds() < 7 * 24 * 60 * 60:
+                pypi_version = state.state["pypi_version"]
+
+        # Refresh the version if we need to or just see if we need to warn
+        if pypi_version is None:
+            pypi_version = get_pypi_version()
+
+            # Save that we've performed a check
+            state.save(pypi_version, current_time)
+
+        conrad_version = pkg_resources.parse_version(__version__)
+        remote_version = pkg_resources.parse_version(pypi_version)
+
+        if conrad_version < remote_version:
+            pip_cmd = "{} -m pip".format(sys.executable)
+            logger.warning(
+                f"You are using conrad version {__version__}; however,"
+                f" version {pypi_version} is available.\n"
+                "You should consider upgrading with"
+                f" '{pip_cmd} install --upgrade conference-radar'."
+            )
+    except Exception:
+        logger.debug(
+            "There was an error checking the latest version of conrad",
+            exc_info=True,
+        )
+
 
 def initialize_database():
     from .models import Base

setup.py

@@ -43,7 +43,7 @@ def setup_package():
         packages=find_packages(exclude=("tests",)),
         install_requires=requires,
         extras_require={"dev": dev_requires},
-        entry_points={"console_scripts": ["conrad = conrad.cli:cli"]},
+        entry_points={"console_scripts": ["conrad = conrad.__main__:main"]},
         classifiers=[
             # Trove classifiers
             # Full list: https://pypi.python.org/pypi?%3Aaction=list_classifiers