Skip localhost URLs in link checker

[Copilot]

Link checker was attempting network connections to localhost URLs in documentation examples, causing unnecessary timeouts and false positives.

Changes

• Added _is_localhost_url() to detect localhost patterns before network calls
• Updated _should_skip_url() to filter localhost URLs during link extraction

Localhost patterns handled

• localhost (any port)
• 127.x.x.x (entire loopback range)
• [::1] (IPv6 localhost with bracket parsing)
• 0.0.0.0

Implementation

def _is_localhost_url(self, url: str) -> bool:
    parsed = urlparse(url)
    if not parsed.netloc:
        return False
    
    netloc = parsed.netloc.lower()
    # Handle IPv6 bracket notation: [::1]:port
    if netloc.startswith('['):
        hostname = netloc.split(']')[0] + ']'
    else:
        hostname = netloc.split(':')[0]
    
    localhost_patterns = ['localhost', '127.0.0.1', '[::1]', '0.0.0.0']
    return hostname in localhost_patterns or hostname.startswith('127.')

URLs are filtered before entering the checking pipeline, eliminating connection attempts entirely.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• www.amazon.com
  • Triggering command: /usr/bin/python3 python3 bin/quality/check-links.py docs/rest-api-examples.md (dns block)
• www.google.com
  • Triggering command: /usr/bin/python3 python3 bin/quality/check-links.py /tmp/link-checker-test/test-localhost.md --root /tmp/link-checker-test (dns block)
  • Triggering command: /usr/bin/python3 python3 /home/REDACTED/work/Browser4/Browser4/bin/quality/check-links.py /tmp/link-checker-test/test-localhost.md --root /tmp/link-checker-test (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

---

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[github-actions]

Qodana for JVM

1660 new problems were found

Inspection name	Severity	Problems
Incorrect Spring Core XML-based application context	🔴 Failure	455
Incorrect constructor injection in XML Spring bean	🔴 Failure	4
Malicious dependency	🔴 Failure	2
Unresolved reference in KDoc	🔶 Warning	208
Unreachable code	🔶 Warning	78
Assigned value is never read	🔶 Warning	10
Kotlin Maven Plugin misconfigured	🔶 Warning	10
Copy constructor misses field	🔶 Warning	8
Non-serializable class with 'serialVersionUID'	🔶 Warning	8
Method does not call super method	🔶 Warning	8
Static initializer references subclass	🔶 Warning	8
Constant conditions	🔶 Warning	5
Statement with empty body	🔶 Warning	4
Suspicious collection method call	🔶 Warning	4
Nullability and data flow problems	🔶 Warning	3
Nullable type argument in Java collection that doesn't support nulls	🔶 Warning	3
Single character alternation	🔶 Warning	3
Non-safe string is used as SQL	🔶 Warning	3
Unused assignment	🔶 Warning	3
Duplicate character in character class	🔶 Warning	2
Variable is never read	🔶 Warning	2
Wrapper type may be primitive	🔶 Warning	2
'equals()' and 'hashCode()' not paired	🔶 Warning	1
Malformed format string	🔶 Warning	1
Mismatched query and update of collection	🔶 Warning	1
Unnecessary non-capturing group	🔶 Warning	1
Call to 'System.getProperty(str)' could be simplified	🔶 Warning	1
Function or property has platform type	◽️ Notice	793
Redundant interpolation prefix	◽️ Notice	21
Constant conditions	◽️ Notice	4
Argument could be converted to 'Set' to improve performance	◽️ Notice	3
Constant values	◽️ Notice	1

☁️ View the detailed Qodana report

Detected 10 dependencies

Third-party software list

This page lists the third-party software dependencies used in project

Dependency	Version	Licenses
cdt-kotlin-client	4.0.0	Apache-2.0
crawler-commons	0.5	Apache-2.0
gora-shaded-mongodb	0.9	Apache-2.0
kotlin-sdk-client-jvm	0.8.1	MIT
kotlin-sdk-core-jvm	0.8.1	MIT
playwright	1.50.0	Apache-2.0
snakeyaml	2.2	Apache-2.0
springdoc-openapi-starter-webmvc-ui	2.6.0	Apache-2.0
stax2-api	4.2.1	BSD-3-Clause
woodstox-core-asl	4.4.1	Apache-2.0

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