parseURI is:exact

Turn a string containing a URI into a URI. Returns Nothing if the string is not a valid URI; (an absolute URI with optional fragment identifier). NOTE: this is different from the previous network.URI, whose parseURI function works like parseURIReference in this module.

Parse a strict ByteString into a URI or an error. Example:

>>> parseURI strictURIParserOptions "http://www.example.org/foo?bar=baz#quux"
Right (URI {uriScheme = Scheme {schemeBS = "http"}, uriAuthority = Just (Authority {authorityUserInfo = Nothing, authorityHost = Host {hostBS = "www.example.org"}, authorityPort = Nothing}), uriPath = "/foo", uriQuery = Query {queryPairs = [("bar","baz")]}, uriFragment = Just "quux"})

>>> parseURI strictURIParserOptions "$$$$://badurl.example.org"
Left (MalformedScheme NonAlphaLeading)

There are some urls that you'll encounter which defy the spec, such as those with square brackets in the query string. If you must be able to parse those, you can use "laxURIParserOptions" or specify your own

>>> parseURI strictURIParserOptions "http://www.example.org/foo?bar[]=baz"
Left MalformedQuery

>>> parseURI laxURIParserOptions "http://www.example.org/foo?bar[]=baz"
Right (URI {uriScheme = Scheme {schemeBS = "http"}, uriAuthority = Just (Authority {authorityUserInfo = Nothing, authorityHost = Host {hostBS = "www.example.org"}, authorityPort = Nothing}), uriPath = "/foo", uriQuery = Query {queryPairs = [("bar[]","baz")]}, uriFragment = Nothing})

>>> let myLaxOptions = URIParserOptions { upoValidQueryChar = liftA2 (||) (upoValidQueryChar strictURIParserOptions) (inClass "[]")}

>>> parseURI myLaxOptions "http://www.example.org/foo?bar[]=baz"
Right (URI {uriScheme = Scheme {schemeBS = "http"}, uriAuthority = Just (Authority {authorityUserInfo = Nothing, authorityHost = Host {hostBS = "www.example.org"}, authorityPort = Nothing}), uriPath = "/foo", uriQuery = Query {queryPairs = [("bar[]","baz")]}, uriFragment = Nothing})

Parses a uri such that parseURI "https://example.com" === Just (URI "https:" "//example.com"