I'm not 100% sure what the circumstances of failure are, but I'm only seeing it with undeleted items that are now redirects.
This code:
import pywikibot
site = pywikibot.Site("wikidata", "wikidata")
qid = "Q124382633"
item = pywikibot.ItemPage(site, qid)
print(item.exists(), item.isRedirectPage())prints False False, but it should return True True because Q124382633 exists and is a redirect. It works as expected for Q119442711 which is also an undeleted redirect.
Strange, gerRedirectTarget works:
item.getRedirectTarget()
ItemPage('Q119442711')but get() fails:
x = item.get()
Traceback (most recent call last):
File "C:\pwb\GIT\core\pywikibot\page\_wikibase.py", line 734, in get
data = WikibaseEntity.get(self, force=force)
File "C:\pwb\GIT\core\pywikibot\page\_wikibase.py", line 267, in get
raise NoWikibaseEntityError(self)
pywikibot.exceptions.NoWikibaseEntityError: Entity 'Q124382633' doesn't exist on wikidata:wikidata
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "<pyshell#11>", line 1, in <module>
x = item.get()
File "C:\pwb\GIT\core\pywikibot\page\_wikibase.py", line 1152, in get
data = super().get(force, *args, **kwargs)
File "C:\pwb\GIT\core\pywikibot\page\_wikibase.py", line 741, in get
raise NoPageError(self)
pywikibot.exceptions.NoPageError: Page [[wikidata:Q124382633]] doesn't exist.I guess this an upstream issue. The releated query is
https://www.wikidata.org/w/api.php?ids=Q124382633&action=wbgetentities
and returns
{
"entities": {
"Q124382633": {
"id": "Q124382633",
"missing": ""
}
},
"success": 1
}whereas https://www.wikidata.org/w/api.php?ids=Q119442711&action=wbgetentities gives the content.
Maybe this is caused by the double redirect?
We could use getRedirectTarget to test for redirects:
>>> import pywikibot
>>> site = pywikibot.Site('wikidata')
>>> item = pywikibot.ItemPage(site, 'Q124382633')
>>> item.getRedirectTarget()
ItemPage('Q119442711')
>>> item = pywikibot.ItemPage(site, 'Q119442711')
>>> item.getRedirectTarget()
ItemPage('Q116896444')
>>> item = pywikibot.ItemPage(site, 'Q116896444')
>>> item.getRedirectTarget()
Traceback (most recent call last):
File "<pyshell#16>", line 1, in <module>
item.getRedirectTarget()
File "C:\pwb\GIT\core\pywikibot\page\_wikibase.py", line 1185, in getRedirectTarget
target = super().getRedirectTarget(ignore_section=ignore_section)
File "C:\pwb\GIT\core\pywikibot\page\_basepage.py", line 1827, in getRedirectTarget
return self.site.getredirtarget(self, ignore_section=ignore_section)
File "C:\pwb\GIT\core\pywikibot\site\_apisite.py", line 1603, in getredirtarget
raise IsNotRedirectPageError(page)
pywikibot.exceptions.IsNotRedirectPageError: Page [[wikidata:Q116896444]] is not a redirect page.
>>> item = pywikibot.ItemPage(site, 'Q1168964449999')
>>> item.getRedirectTarget()
Traceback (most recent call last):
File "<pyshell#18>", line 1, in <module>
item.getRedirectTarget()
File "C:\pwb\GIT\core\pywikibot\page\_wikibase.py", line 1185, in getRedirectTarget
target = super().getRedirectTarget(ignore_section=ignore_section)
File "C:\pwb\GIT\core\pywikibot\page\_basepage.py", line 1827, in getRedirectTarget
return self.site.getredirtarget(self, ignore_section=ignore_section)
File "C:\pwb\GIT\core\pywikibot\site\_apisite.py", line 1603, in getredirtarget
raise IsNotRedirectPageError(page)
pywikibot.exceptions.IsNotRedirectPageError: Page [[wikidata:Q1168964449999]] is not a redirect page.Solved upstream with redirect change. The problem exists for double redirects I guess.
Lets look at the example of Q192393 → Q213543 → Q7 on test.wikidata.
Behavior of pywikibot :
pywikibot.Page(site, "Q192393").exists() # True pywikibot.Page(site, "Q192393").isRedirectPage() # True pywikibot.Page(site, "Q192393").getRedirectTarget() # [[test:Q213543]] print(page:=pywikibot.ItemPage(repo, "Q192393"), page.exists(), page.isRedirectPage()) # [[test:Q192393]] False False pywikibot.ItemPage(repo, "Q192393").exists() # False pywikibot.ItemPage(repo, "Q192393").isRedirectPage() # True! (because exists() has never been called on the instance) pywikibot.ItemPage(repo, "Q192393").getRedirectTarget() # [[test:Q213543]] (because super().getRedirectTarget() is called)
The inconstant return value of isRedirectPage is due to the implementation in WikibaseEntity (_content is initialized when we call exists()) :
def isRedirectPage(self):
"""Return True if item is a redirect, False if not or not existing."""
if hasattr(self, '_content') and not hasattr(self, '_isredir'):
self._isredir = self.id != self._content.get('id', self.id)
return self._isredir
return super().isRedirectPage()Behavior of API:
If redirects=yes (default), the function getEntityRevision catches the first redirection and try to resolve it (but not recursively, setting redirects=no).
Test with redirects=no : https://test.wikidata.org/w/api.php?action=wbgetentities&ids=Q192393%7CQ213543&redirects=no (neither of them "exists" in the repository)
Test with redirects=yes : https://test.wikidata.org/w/api.php?action=wbgetentities&ids=Q192393%7CQ213543&redirects=yes
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