39 lines
1.9 KiB
Plaintext
39 lines
1.9 KiB
Plaintext
import assertString from './util/assertString';
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/*
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Checks if the provided string matches to a correct Media type format (MIME type)
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This function only checks is the string format follows the
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etablished rules by the according RFC specifications.
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This function supports 'charset' in textual media types
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(https://tools.ietf.org/html/rfc6657).
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This function does not check against all the media types listed
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by the IANA (https://www.iana.org/assignments/media-types/media-types.xhtml)
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because of lightness purposes : it would require to include
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all these MIME types in this librairy, which would weigh it
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significantly. This kind of effort maybe is not worth for the use that
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this function has in this entire librairy.
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More informations in the RFC specifications :
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- https://tools.ietf.org/html/rfc2045
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- https://tools.ietf.org/html/rfc2046
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- https://tools.ietf.org/html/rfc7231#section-3.1.1.1
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- https://tools.ietf.org/html/rfc7231#section-3.1.1.5
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*/
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// Match simple MIME types
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// NB :
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// Subtype length must not exceed 100 characters.
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// This rule does not comply to the RFC specs (what is the max length ?).
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var mimeTypeSimple = /^(application|audio|font|image|message|model|multipart|text|video)\/[a-zA-Z0-9\.\-\+_]{1,100}$/i; // eslint-disable-line max-len
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// Handle "charset" in "text/*"
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var mimeTypeText = /^text\/[a-zA-Z0-9\.\-\+]{1,100};\s?charset=("[a-zA-Z0-9\.\-\+\s]{0,70}"|[a-zA-Z0-9\.\-\+]{0,70})(\s?\([a-zA-Z0-9\.\-\+\s]{1,20}\))?$/i; // eslint-disable-line max-len
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// Handle "boundary" in "multipart/*"
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var mimeTypeMultipart = /^multipart\/[a-zA-Z0-9\.\-\+]{1,100}(;\s?(boundary|charset)=("[a-zA-Z0-9\.\-\+\s]{0,70}"|[a-zA-Z0-9\.\-\+]{0,70})(\s?\([a-zA-Z0-9\.\-\+\s]{1,20}\))?){0,2}$/i; // eslint-disable-line max-len
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export default function isMimeType(str) {
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assertString(str);
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return mimeTypeSimple.test(str) || mimeTypeText.test(str) || mimeTypeMultipart.test(str);
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} |