レッスン 1
URL Components 日本語ガイド
日本語の url parser url components ガイド: Break URLs into scheme, host, port, path, query, and fragment.
このコンテンツはまだ日本語で用意されていません。ローカライズが完了するまで English 版を表示しています。
A URL is a structured address, not just a string. Debugging becomes easier when you separate its components before interpreting it.
https://api.example.com:8443/v1/items?q=blue&page=2#results
This URL contains:
- Scheme:
https - Host:
api.example.com - Port:
8443 - Path:
/v1/items - Query:
q=blue&page=2 - Fragment:
results
Scheme
The scheme tells clients how to interpret the rest of the URL. https, http, mailto, and file all imply different rules.
Host and port
The host identifies the server. The port selects the network port. Default ports such as 443 for HTTPS are often omitted in display, but explicit ports matter in local development and service debugging.
Path
The path identifies a resource within the host. It is hierarchical, so /users/42 and /users/42/ may be different depending on the server.
Query
The query begins after ? and often carries filters, pagination, sort order, tracking fields, and OAuth state. Query parsing is not always one-size-fits-all because repeated keys and empty values can be interpreted differently.
Fragment
The fragment begins after #. Browsers use it client-side and do not normally send it to the server in HTTP requests. That matters when debugging why a server cannot see part of a link.
Treat each component as a boundary. Most URL bugs come from encoding or rebuilding across the wrong boundary.