View Source MyApp.Cldr.AcceptLanguage (Cldr v2.39.2)
Parses HTTP Accept-Language
header values as defined in
rfc2616.
The Accept-Language request-header field is similar to Accept, but restricts
the set of natural languages that are preferred as a response to the request.
Language tags function are provided in Cldr.LanguageTag
.
The format of an Accept-Language
header is as follows in ABNF
format:
Accept-Language = "Accept-Language" ":"
1#( language-range [ ";" "q" "=" qvalue ] )
language-range = ( ( 1*8ALPHA *( "-" 1*8ALPHA ) ) | "*" )
Each language-range MAY be given an associated quality value which represents an estimate of the user's preference for the languages specified by that range. The quality value defaults to "q=1". For example,
Accept-Language: da, en-gb;q=0.8, en;q=0.7
would mean: "I prefer Danish, but will accept British English and other types of English."
Summary
Functions
Parse an Accept-Language
string and return the best match for
a configured Cldr
locale.
Parses an Accept-Language
header value in its string
or tokenized form to return a tuple of the form
{:ok, [{quality, %Cldr.LanguageTag{}}, ...]}
sorted by quality.
Parses an Accept-Language
header value in its string
or tokenized form to produce a list of tuples of the form
[{quality, %Cldr.LanguageTag{}}, ...]
sorted by quality
in descending order.
Functions
@spec best_match(String.t()) :: {:ok, Cldr.LanguageTag.t()} | {:error, {Cldr.AcceptLanguageError | Cldr.NoMatchingLocale, String.t()}}
Parse an Accept-Language
string and return the best match for
a configured Cldr
locale.
Arguments
accept_language
is a string representing an accept language header
Returns
{:ok, language_tag}
or{:error, reason}
Examples
iex> MyApp.Cldr.AcceptLanguage.best_match("da;q=0.1,zh-TW;q=0.3", TestBackend.Cldr)
{:ok,
%Cldr.LanguageTag{
backend: TestBackend.Cldr,
canonical_locale_name: "zh-TW",
cldr_locale_name: :"zh-Hant",
language_subtags: [],
extensions: %{},
gettext_locale_name: nil,
language: "zh",
locale: %{},
private_use: [],
rbnf_locale_name: :"zh-Hant",
requested_locale_name: "zh-TW",
script: :Hant,
territory: :TW,
transform: %{},
language_variants: []
}}
iex> MyApp.Cldr.AcceptLanguage.best_match("da;q=0.1,zh-TW;q=0.3", TestBackend.Cldr)
{:ok,
%Cldr.LanguageTag{
backend: TestBackend.Cldr,
canonical_locale_name: "zh-TW",
cldr_locale_name: :"zh-Hant",
language_subtags: [],
extensions: %{},
gettext_locale_name: nil,
language: "zh",
locale: %{},
private_use: [],
rbnf_locale_name: :"zh-Hant",
requested_locale_name: "zh-TW",
script: :Hant,
territory: :TW,
transform: %{},
language_variants: []
}}
iex> MyApp.Cldr.AcceptLanguage.best_match("xx,yy;q=0.3")
{:error,
{Cldr.NoMatchingLocale,
"No configured locale could be matched to \"xx,yy;q=0.3\""}}
iex> MyApp.Cldr.AcceptLanguage.best_match("invalid_tag")
{:error, {Cldr.LanguageTag.ParseError,
"Expected a BCP47 language tag. Could not parse the remaining \"g\" starting at position 11"}}
@spec parse([{float(), String.t()}, ...] | String.t()) :: {:ok, [ {float(), Cldr.LanguageTag.t()} | {:error, {Cldr.InvalidLanguageTag, String.t()}}, ... ]} | {:error, {Cldr.AcceptLanguageError, String.t()}}
Parses an Accept-Language
header value in its string
or tokenized form to return a tuple of the form
{:ok, [{quality, %Cldr.LanguageTag{}}, ...]}
sorted by quality.
Arguments
accept-language
is any string in the format defined by rfc2616backend
is any module that includesuse Cldr
and therefore is aCldr
backend module
Returns
{:ok, [{quality, language_tag}, ...]}
or{:error, {Cldr.AcceptLanguageError, String.t}}
If at least one valid language tag is found but errors are also
detected on one more more tags, an {ok, list}
tuple is returned
with an error tuple for each invalid tag added at the end of the list.
Example
iex> Cldr.AcceptLanguage.parse("da,zh-TW;q=0.3", TestBackend.Cldr)
{:ok,
[
{1.0,
%Cldr.LanguageTag{
backend: TestBackend.Cldr,
canonical_locale_name: "da",
cldr_locale_name: :da,
language_subtags: [],
extensions: %{},
gettext_locale_name: nil,
language: "da",
locale: %{},
private_use: [],
rbnf_locale_name: :da,
requested_locale_name: "da",
script: :Latn,
territory: :DK,
transform: %{},
language_variants: []
}},
{0.3,
%Cldr.LanguageTag{
backend: TestBackend.Cldr,
canonical_locale_name: "zh-TW",
cldr_locale_name: :"zh-Hant",
language_subtags: [],
extensions: %{},
gettext_locale_name: nil,
language: "zh",
locale: %{},
private_use: [],
rbnf_locale_name: :"zh-Hant",
requested_locale_name: "zh-TW",
script: :Hant,
territory: :TW,
transform: %{},
language_variants: []
}}
]}
iex> MyApp.Cldr.AcceptLanguage.parse("invalid_tag")
{:error,
{Cldr.LanguageTag.ParseError,
"Expected a BCP47 language tag. Could not parse the remaining \"g\" starting at position 11"}}
iex> MyApp.Cldr.AcceptLanguage.parse("da,zh-TW;q=0.3,invalid_tag")
{:ok,
[
{1.0,
%Cldr.LanguageTag{
backend: TestBackend.Cldr,
canonical_locale_name: "da",
cldr_locale_name: :da,
language_subtags: [],
extensions: %{},
gettext_locale_name: nil,
language: "da",
locale: %{},
private_use: [],
rbnf_locale_name: :da,
requested_locale_name: "da",
script: :Latn,
territory: :DK,
transform: %{},
language_variants: []
}},
{0.3,
%Cldr.LanguageTag{
backend: TestBackend.Cldr,
canonical_locale_name: "zh-TW",
cldr_locale_name: :"zh-Hant",
language_subtags: [],
extensions: %{},
gettext_locale_name: nil,
language: "zh",
locale: %{},
private_use: [],
rbnf_locale_name: :"zh-Hant",
requested_locale_name: "zh-TW",
script: :Hant,
territory: :TW,
transform: %{},
language_variants: []
}},
{:error,
{Cldr.LanguageTag.ParseError,
"Expected a BCP47 language tag. Could not parse the remaining \"g\" starting at position 11"}}
]}
Parses an Accept-Language
header value in its string
or tokenized form to produce a list of tuples of the form
[{quality, %Cldr.LanguageTag{}}, ...]
sorted by quality
in descending order.
Arguments
accept-language
is any string in the format defined by rfc2616
Returns
{:ok, [{quality, language_tag}, ...]}
orraises a
Cldr.AcceptLanguageError
exception
If at least one valid language tag is found but errors are also
detected on one more more tags, an {ok, list}
tuple is returned
with an error tuple for each invalid tag added at the end of the list.
Example
iex> MyApp.Cldr.AcceptLanguage.parse!("da,zh-TW;q=0.3")
[
{1.0,
%Cldr.LanguageTag{
backend: TestBackend.Cldr,
canonical_locale_name: "da",
cldr_locale_name: :da,
language_subtags: [],
extensions: %{},
gettext_locale_name: nil,
language: "da",
locale: %{},
private_use: [],
rbnf_locale_name: :da,
requested_locale_name: "da",
script: :Latn,
territory: :DK,
transform: %{},
language_variants: []
}},
{0.3,
%Cldr.LanguageTag{
backend: TestBackend.Cldr,
canonical_locale_name: "zh-TW",
cldr_locale_name: :"zh-Hant",
language_subtags: [],
extensions: %{},
gettext_locale_name: nil,
language: "zh",
locale: %{},
private_use: [],
rbnf_locale_name: :"zh-Hant",
requested_locale_name: "zh-TW",
script: :Hant,
territory: :TW,
transform: %{},
language_variants: []
}}
]
MyApp.Cldr.AcceptLanguage.parse! "invalid_tag"
** (Cldr.AcceptLanguageError) "Expected a BCP47 language tag. Could not parse the remaining "g" starting at position 11
(ex_cldr) lib/cldr/accept_language.ex:304: Cldr.AcceptLanguage.parse!/1
iex> MyApp.Cldr.AcceptLanguage.parse!("da,zh-TW;q=0.3,invalid_tag")
[
{1.0,
%Cldr.LanguageTag{
backend: TestBackend.Cldr,
canonical_locale_name: "da",
cldr_locale_name: :da,
language_subtags: [],
extensions: %{},
gettext_locale_name: nil,
language: "da",
locale: %{},
private_use: [],
rbnf_locale_name: :da,
requested_locale_name: "da",
script: :Latn,
territory: :DK,
transform: %{},
language_variants: []
}},
{0.3,
%Cldr.LanguageTag{
backend: TestBackend.Cldr,
canonical_locale_name: "zh-TW",
cldr_locale_name: :"zh-Hant",
language_subtags: [],
extensions: %{},
gettext_locale_name: nil,
language: "zh",
locale: %{},
private_use: [],
rbnf_locale_name: :"zh-Hant",
requested_locale_name: "zh-TW",
script: :Hant,
territory: :TW,
transform: %{},
language_variants: []
}},
{:error,
{Cldr.LanguageTag.ParseError,
"Expected a BCP47 language tag. Could not parse the remaining \"g\" starting at position 11"}}
]