Find items with conflicting sitelinks, for a given list of item ids.

findSiteLinkConflicts.php

<?php

function errEcho( $str ) {
	file_put_contents( 'php://stderr', $str, FILE_APPEND );
}

if ( $argc !== 2 || $argv[1] === '--help' ) {
	errEcho( "Find items with conflicting sitelinks, for a given list of item ids.\n\n" );
	errEcho( "Usage: findSiteLinkConflicts [--help] file-with-itemids\n" );
	exit( 0 );
}

$fileName = $argv[1];
$file = fopen( $fileName, 'r' );
if ( !$file ) {
	errEcho( "Could not open $fileName for reading.\n" );
	exit( 1 );
}

while ( ( $line = fgets( $file ) ) !== false ) {
	$itemId = trim( $line );
	if ( !preg_match( '/^Q[1-9]\d+\z/', $itemId ) ) {
		errEcho( "Skipping input row: \"$itemId\"\n" );
		continue;
	}

	$subjectEntity = json_decode(
		file_get_contents(
			'https://www.wikidata.org/w/api.php?action=wbgetentities&ids=' . urlencode( $itemId ) .
			'&props=sitelinks&format=json'
		),
		true
	);
	if ( !isset( $subjectEntity['entities'] ) ) {
		errEcho( "Failed reading Item $itemId\n" );
		continue;
	}
	errEcho( "Checking sitelinks for Item $itemId\n" );

	$requestCount = 0;
	$conflicts = [];
	$siteLinks = $subjectEntity['entities'][$itemId]['sitelinks'];
	foreach ( $siteLinks as $siteLink ) {
		$siteId = $siteLink['site'];
		$pageTitle = $siteLink['title'];

		$apiJson = file_get_contents(
			'https://www.wikidata.org/w/api.php?action=wbgetentities&sites=' . urlencode( $siteId ) .
			'&titles=' . urlencode( $pageTitle ) . '&props=&format=json'
		);
		$apiResponse = json_decode( $apiJson, true );

		$requestCount++;
		if ( $requestCount % 10 === 0 ) {
			errEcho( "Got 10 sitelinks for $itemId\n" );
		}

		if ( !isset( $apiResponse['entities'] ) ) {
			continue;
		}
		$conflicts[] = array_keys( $apiResponse['entities'] )[0];
	}
	$conflicts = array_diff( array_unique( $conflicts ), [ $itemId ] );
	echo "Item $itemId conflicts with: " . implode( ', ', $conflicts ) . "\n";
}

errEcho( "\nDone\n" );