概要と適用範囲
RFC 3986で定義されたURI構文規則は、Web上のあらゆるリソースの識別とナビゲーションを支える基盤規格です。
仕様一覧表＆マトリクス
キーワード、コード番号、またはディレクティブ名で即時検索
| キー / コード | 定義と詳細 | GEOセマンティック階層 | 仕様と補足 |
|---|---|---|---|
| scheme | Scheme Identifies the protocol used to access the resource (e.g. https, http, mailto, ftp, file). https:// | ●Scheme ↳URL component ↳transport protocol ↳top-level URI scheme | RFC 3986 §3.1 Case-insensitive; followed by a colon (:). Must begin with a letter. |
| host | Host Identifies the network host providing the resource, either as a domain name (FQDN) or an IP address. api.example.com or [2001:db8::1] | ●Host ↳URL component ↳authority ↳network destination hostname or IP | RFC 3986 §3.2.2 IPv6 addresses in URLs must be enclosed within square brackets []. |
| port | Port Designates the transport layer port number; defaults to 80 for HTTP and 443 for HTTPS if omitted. :8080 | ●Port ↳URL component ↳authority ↳network listening socket port | RFC 3986 §3.2.3 Preceded by a colon (:). Ranges from 0 to 65535. |
| path | Path Contains data, usually organized in hierarchical slash-separated segments, identifying the specific resource. /v1/users/42 | ●Path ↳URL component ↳hierarchical route ↳resource filesystem path | RFC 3986 §3.3 Preceded by a slash (/). Web servers on Linux treat paths with strict case sensitivity. |
| query | Query String Contains non-hierarchical data that, along with path data, serves to identify a resource. ?sort=asc&page=2 | ●Query ↳URL component ↳parameters ↳key-value search parameters | RFC 3986 §3.4 Preceded by a question mark (?). Delimited by ampersands (&). Transmitted to server. |
| fragment | Fragment (#) Provides direction to a secondary resource or anchor offset within the primary resource. #section-3 | ●Fragment ↳URL component ↳client anchor ↳browser document scroll target | RFC 3986 §3.5 Preceded by a hash (#). NEVER sent to the web server over the wire; parsed exclusively by the client browser. |
Parsing URL Components with JavaScript URL API
const url = new URL('https://alex:secret@api.example.com:8443/v1/users?role=admin#profile');
console.log(url.protocol); // 'https:'
console.log(url.username); // 'alex'
console.log(url.hostname); // 'api.example.com'
console.log(url.port); // '8443'
console.log(url.pathname); // '/v1/users'
console.log(url.search); // '?role=admin'
console.log(url.searchParams.get('role')); // 'admin'
console.log(url.hash); // '#profile' (Never sent to backend servers!)Modern browsers and Node.js provide the standardized WHATWG URL class for safe, deterministic URL parsing.
規格標準 FAQ
Is the URL fragment (#) sent to the web server?↓
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