arizona_user_agent (arizona v0.4.0)

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Pure, best-effort User-Agent classification helpers.

Each function takes the raw User-Agent string (from arizona_req:user_agent/1) and answers one question, so a caller composes only the checks it needs instead of building a map of fields it will not use.

The checks are heuristic substring matches -- good enough to pick a render target (browser vs native app) but not authoritative. When the coarse answer is not enough, match the raw string yourself: you know your own native client's UA.

{UA, _Req1} = arizona_req:user_agent(Req),
case arizona_user_agent:browser(UA) of
    true -> ?html(...);
    false -> ?native(...)
end.

Summary

Functions

browser(UserAgent)

Whether the User-Agent looks like a web browser or webview.

mobile(UserAgent)

Whether the User-Agent looks like a mobile device.

os(UserAgent)

Coarse operating-system guess from a User-Agent, or other when nothing matches.

Functions

browser(UserAgent)

-spec browser(UserAgent) -> boolean() when UserAgent :: binary().

Whether the User-Agent looks like a web browser or webview.

True when the UA carries Mozilla -- every mainstream browser and webview does. A native app's HTTP stack typically does not, which is the signal to render a native tree instead of HTML.

mobile(UserAgent)

-spec mobile(UserAgent) -> boolean() when UserAgent :: binary().

Whether the User-Agent looks like a mobile device.

Best effort: true when the UA carries Mobi (most mobile browsers) or Android. Some tablets -- recent iPad Safari, for instance -- report a desktop UA and read as false.

os(UserAgent)

-spec os(UserAgent) -> watchos | tvos | webos | tizen | ios | android | windows | macos | linux | other
            when UserAgent :: binary().

Coarse operating-system guess from a User-Agent, or other when nothing matches.

Order matters where UAs overlap, so the more specific substrings are checked first: Apple TV / Apple Watch UAs also carry Mac OS X; webOS / Tizen / Android UAs carry Linux; iOS UAs carry Mac OS X. The smart-TV ones (tvos/webos/ tizen) come from real TV-browser UAs and are reliable. watchos and native apps rely on a descriptive UA -- most native HTTP stacks send a generic UA that names no platform (→ other), so when you control the client prefer an explicit signal (a query param/header) over this heuristic.