Parse and compare dates in Python using only the standard library












0















Some time ago, I had to write a small script in python that, among others, parsed ISO8601-formatted date string and compared it with the current datetime.



As I do not code in Python, I was looking around for a solution. To my big disappointment, all suggested solutions that I found suggested using third-party libraries to accomplish the job. Essentially, I ended up doing this (simplified for brevity):



import iso8601
import pytz

utc = pytz.UTC()
event_date = iso8601.parse_date('2002-10-02T15:00:00.05Z')
now = utc.localize(datetime.utcnow())

# Only now I was able to compare the dates
if event_date - timedelta(hours=3) < now:
<do something>


I am not comfortable with the fact that I had to import two third-party libraries for such common task.



How can I accomplish the above with only what's only available in the Python standard lib and avoid errors like:




  • can't compare offset-naive and offset-aware datetimes

  • cannot compare tz-naive and tz-aware datetime-like objects










share|improve this question























  • Did you see this topic: stackoverflow.com/questions/8142364/how-to-compare-two-dates

    – Denis Rasulev
    Nov 16 '18 at 9:22






  • 2





    Datetime module should help

    – artona
    Nov 16 '18 at 9:24











  • @DenisRasulev, these are not the same, in the topic you pasted homogeneous dates are compared. There is an array of problems when you attempt to compare dates instantiated differently (e.g. parsed from ISO8601).

    – luqo33
    Nov 16 '18 at 10:45
















0















Some time ago, I had to write a small script in python that, among others, parsed ISO8601-formatted date string and compared it with the current datetime.



As I do not code in Python, I was looking around for a solution. To my big disappointment, all suggested solutions that I found suggested using third-party libraries to accomplish the job. Essentially, I ended up doing this (simplified for brevity):



import iso8601
import pytz

utc = pytz.UTC()
event_date = iso8601.parse_date('2002-10-02T15:00:00.05Z')
now = utc.localize(datetime.utcnow())

# Only now I was able to compare the dates
if event_date - timedelta(hours=3) < now:
<do something>


I am not comfortable with the fact that I had to import two third-party libraries for such common task.



How can I accomplish the above with only what's only available in the Python standard lib and avoid errors like:




  • can't compare offset-naive and offset-aware datetimes

  • cannot compare tz-naive and tz-aware datetime-like objects










share|improve this question























  • Did you see this topic: stackoverflow.com/questions/8142364/how-to-compare-two-dates

    – Denis Rasulev
    Nov 16 '18 at 9:22






  • 2





    Datetime module should help

    – artona
    Nov 16 '18 at 9:24











  • @DenisRasulev, these are not the same, in the topic you pasted homogeneous dates are compared. There is an array of problems when you attempt to compare dates instantiated differently (e.g. parsed from ISO8601).

    – luqo33
    Nov 16 '18 at 10:45














0












0








0








Some time ago, I had to write a small script in python that, among others, parsed ISO8601-formatted date string and compared it with the current datetime.



As I do not code in Python, I was looking around for a solution. To my big disappointment, all suggested solutions that I found suggested using third-party libraries to accomplish the job. Essentially, I ended up doing this (simplified for brevity):



import iso8601
import pytz

utc = pytz.UTC()
event_date = iso8601.parse_date('2002-10-02T15:00:00.05Z')
now = utc.localize(datetime.utcnow())

# Only now I was able to compare the dates
if event_date - timedelta(hours=3) < now:
<do something>


I am not comfortable with the fact that I had to import two third-party libraries for such common task.



How can I accomplish the above with only what's only available in the Python standard lib and avoid errors like:




  • can't compare offset-naive and offset-aware datetimes

  • cannot compare tz-naive and tz-aware datetime-like objects










share|improve this question














Some time ago, I had to write a small script in python that, among others, parsed ISO8601-formatted date string and compared it with the current datetime.



As I do not code in Python, I was looking around for a solution. To my big disappointment, all suggested solutions that I found suggested using third-party libraries to accomplish the job. Essentially, I ended up doing this (simplified for brevity):



import iso8601
import pytz

utc = pytz.UTC()
event_date = iso8601.parse_date('2002-10-02T15:00:00.05Z')
now = utc.localize(datetime.utcnow())

# Only now I was able to compare the dates
if event_date - timedelta(hours=3) < now:
<do something>


I am not comfortable with the fact that I had to import two third-party libraries for such common task.



How can I accomplish the above with only what's only available in the Python standard lib and avoid errors like:




  • can't compare offset-naive and offset-aware datetimes

  • cannot compare tz-naive and tz-aware datetime-like objects







python datetime






share|improve this question













share|improve this question











share|improve this question




share|improve this question










asked Nov 16 '18 at 9:18









luqo33luqo33

2,43763071




2,43763071













  • Did you see this topic: stackoverflow.com/questions/8142364/how-to-compare-two-dates

    – Denis Rasulev
    Nov 16 '18 at 9:22






  • 2





    Datetime module should help

    – artona
    Nov 16 '18 at 9:24











  • @DenisRasulev, these are not the same, in the topic you pasted homogeneous dates are compared. There is an array of problems when you attempt to compare dates instantiated differently (e.g. parsed from ISO8601).

    – luqo33
    Nov 16 '18 at 10:45



















  • Did you see this topic: stackoverflow.com/questions/8142364/how-to-compare-two-dates

    – Denis Rasulev
    Nov 16 '18 at 9:22






  • 2





    Datetime module should help

    – artona
    Nov 16 '18 at 9:24











  • @DenisRasulev, these are not the same, in the topic you pasted homogeneous dates are compared. There is an array of problems when you attempt to compare dates instantiated differently (e.g. parsed from ISO8601).

    – luqo33
    Nov 16 '18 at 10:45

















Did you see this topic: stackoverflow.com/questions/8142364/how-to-compare-two-dates

– Denis Rasulev
Nov 16 '18 at 9:22





Did you see this topic: stackoverflow.com/questions/8142364/how-to-compare-two-dates

– Denis Rasulev
Nov 16 '18 at 9:22




2




2





Datetime module should help

– artona
Nov 16 '18 at 9:24





Datetime module should help

– artona
Nov 16 '18 at 9:24













@DenisRasulev, these are not the same, in the topic you pasted homogeneous dates are compared. There is an array of problems when you attempt to compare dates instantiated differently (e.g. parsed from ISO8601).

– luqo33
Nov 16 '18 at 10:45





@DenisRasulev, these are not the same, in the topic you pasted homogeneous dates are compared. There is an array of problems when you attempt to compare dates instantiated differently (e.g. parsed from ISO8601).

– luqo33
Nov 16 '18 at 10:45












0






active

oldest

votes












Your Answer






StackExchange.ifUsing("editor", function () {
StackExchange.using("externalEditor", function () {
StackExchange.using("snippets", function () {
StackExchange.snippets.init();
});
});
}, "code-snippets");

StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "1"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);

StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});

function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});


}
});














draft saved

draft discarded


















StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f53334762%2fparse-and-compare-dates-in-python-using-only-the-standard-library%23new-answer', 'question_page');
}
);

Post as a guest















Required, but never shown

























0






active

oldest

votes








0






active

oldest

votes









active

oldest

votes






active

oldest

votes
















draft saved

draft discarded




















































Thanks for contributing an answer to Stack Overflow!


  • Please be sure to answer the question. Provide details and share your research!

But avoid



  • Asking for help, clarification, or responding to other answers.

  • Making statements based on opinion; back them up with references or personal experience.


To learn more, see our tips on writing great answers.




draft saved


draft discarded














StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f53334762%2fparse-and-compare-dates-in-python-using-only-the-standard-library%23new-answer', 'question_page');
}
);

Post as a guest















Required, but never shown





















































Required, but never shown














Required, but never shown












Required, but never shown







Required, but never shown

































Required, but never shown














Required, but never shown












Required, but never shown







Required, but never shown







Popular posts from this blog

Bressuire

Vorschmack

Quarantine