domains.go

package domainutils

import (
	"errors"
	"github.com/dlclark/regexp2"
)

type domainutils struct {
	domain string
}

// New returns a domainutils struct
func New(domain string) domainutils {
	return domainutils{domain: domain}
}

// IsValid checks if a given string fits a domain schemata
func (d *domainutils) IsValid() (bool, error) {
	r, err := regexp2.Compile(`^((?!-))(xn--)?[a-z0-9][a-z0-9-_]{0,61}[a-z0-9]{0,1}\.(xn--)?([a-z0-9\-]{1,61}|[a-z0-9-]{1,30}\.[a-z]{2,})$`, 0)
	if err != nil {
		return false, err
	}
	match, err := r.MatchString(d.domain)
	if err != nil {
		return false, err
	}
	if !match {
		return false, errors.New("Domain doesn't match schemata")
	}
	_, err = d.HasValidTld()
	if err != nil {
		return false, err
	}

	return true, nil
}

// ExtractTld return the top level domain from a domain
func (d *domainutils) ExtractTld() (string, error) {
	r, err := regexp2.Compile(`[^.]+$`, 0)
	if err != nil {
		return "", err
	}
	tld, err := r.FindStringMatch(d.domain)
	if err != nil {
		return "", err
	}
	if tld == nil {
		return "", errors.New("TLD Empty")
	}

	return tld.String(), nil
}

// IsValidTld checks a string against a given list of TLD from iana
func (d *domainutils) IsValidTld(tld string) (bool, error) {
	r, err := regexp2.Compile(`^(aaa|aarp|abb|abbott|abbvie|abogado|abudhabi|ac|academy|accenture|accountant|accountants|aco|active|actor|ad|adac|ads|adult|ae|aeg|aero|aetna|af|afl|ag|agakhan|agency|ai|aig|airbus|airforce|airtel|akdn|al|alibaba|alipay|allfinanz|ally|alsace|alstom|am|amica|amsterdam|analytics|android|anquan|ao|apartments|app|apple|aq|aquarelle|ar|aramco|archi|army|arpa|arte|as|asia|associates|at|attorney|au|auction|audi|audible|audio|author|auto|autos|avianca|aw|aws|ax|axa|az|azure|ba|baby|baidu|band|bank|bar|barcelona|barclaycard|barclays|barefoot|bargains|bauhaus|bayern|bb|bbc|bbva|bcg|bcn|bd|be|beats|beer|bentley|berlin|best|bet|bf|bg|bh|bharti|bi|bible|bid|bike|bing|bingo|bio|biz|bj|black|blackfriday|blog|bloomberg|blue|bm|bms|bmw|bn|bnl|bnpparibas|bo|boats|boehringer|bom|bond|boo|book|boots|bosch|bostik|bot|boutique|br|bradesco|bridgestone|broadway|broker|brother|brussels|bs|bt|budapest|bugatti|build|builders|business|buy|buzz|bv|bw|by|bz|bzh|ca|cab|cafe|cal|call|cam|camera|camp|cancerresearch|canon|capetown|capital|car|caravan|cards|care|career|careers|cars|cartier|casa|cash|casino|cat|catering|cba|cbn|cc|cd|ceb|center|ceo|cern|cf|cfa|cfd|cg|ch|chanel|channel|chase|chat|cheap|chintai|chloe|christmas|chrome|church|ci|cipriani|circle|cisco|citic|city|cityeats|ck|cl|claims|cleaning|click|clinic|clinique|clothing|cloud|club|clubmed|cm|cn|co|coach|codes|coffee|college|cologne|com|commbank|community|company|compare|computer|comsec|condos|construction|consulting|contact|contractors|cooking|cool|coop|corsica|country|coupon|coupons|courses|cr|credit|creditcard|creditunion|cricket|crown|crs|cruises|csc|cu|cuisinella|cv|cw|cx|cy|cymru|cyou|cz|dabur|dad|dance|date|dating|datsun|day|dclk|dds|de|deal|dealer|deals|degree|delivery|dell|deloitte|delta|democrat|dental|dentist|desi|design|dev|dhl|diamonds|diet|digital|direct|directory|discount|dj|dk|dm|dnp|do|docs|dog|doha|domains|dot|download|drive|dtv|dubai|dunlop|dupont|durban|dvag|dz|earth|eat|ec|edeka|edu|education|ee|eg|email|emerck|energy|engineer|engineering|enterprises|epost|epson|equipment|er|ericsson|erni|es|esq|estate|et|eu|eurovision|eus|events|everbank|exchange|expert|exposed|express|extraspace|fage|fail|fairwinds|faith|family|fan|fans|farm|fashion|fast|feedback|ferrero|fi|film|final|finance|financial|fire|firestone|firmdale|fish|fishing|fit|fitness|fj|fk|flickr|flights|flir|florist|flowers|flsmidth|fly|fm|fo|foo|football|ford|forex|forsale|forum|foundation|fox|fr|fresenius|frl|frogans|frontier|ftr|fund|furniture|futbol|fyi|ga|gal|gallery|gallo|gallup|game|games|garden|gb|gbiz|gd|gdn|ge|gea|gent|genting|gf|gg|ggee|gh|gi|gift|gifts|gives|giving|gl|glass|gle|global|globo|gm|gmail|gmbh|gmo|gmx|gn|gold|goldpoint|golf|goo|goodyear|goog|google|gop|got|gov|gp|gq|gr|grainger|graphics|gratis|green|gripe|group|gs|gt|gu|guardian|gucci|guge|guide|guitars|guru|gw|gy|hamburg|hangout|haus|hdfcbank|health|healthcare|help|helsinki|here|hermes|hiphop|hisamitsu|hitachi|hiv|hk|hkt|hm|hn|hockey|holdings|holiday|homedepot|homes|honda|horse|host|hosting|hoteles|hotmail|house|how|hr|hsbc|ht|htc|hu|hyundai|ibm|icbc|ice|icu|id|ie|ifm|iinet|il|im|imamat|imdb|immo|immobilien|in|industries|infiniti|info|ing|ink|institute|insurance|insure|int|international|investments|io|ipiranga|iq|ir|irish|is|iselect|ismaili|ist|istanbul|it|itau|iwc|jaguar|java|jcb|jcp|je|jetzt|jewelry|jlc|jll|jm|jmp|jnj|jo|jobs|joburg|jot|joy|jp|jpmorgan|jprs|juegos|kaufen|kddi|ke|kerryhotels|kerrylogistics|kerryproperties|kfh|kg|kh|ki|kia|kim|kinder|kindle|kitchen|kiwi|km|kn|koeln|komatsu|kosher|kp|kpmg|kpn|kr|krd|kred|kuokgroup|kw|ky|kyoto|kz|la|lacaixa|lamborghini|lamer|lancaster|land|landrover|lanxess|lasalle|lat|latrobe|law|lawyer|lb|lc|lds|lease|leclerc|legal|lego|lexus|lgbt|li|liaison|lidl|life|lifeinsurance|lifestyle|lighting|like|limited|limo|lincoln|linde|link|lipsy|live|living|lixil|lk|loan|loans|locker|locus|lol|london|lotte|lotto|love|lr|ls|lt|ltd|ltda|lu|lupin|luxe|luxury|lv|ly|ma|madrid|maif|maison|makeup|man|management|mango|market|marketing|markets|marriott|mattel|mba|mc|md|me|med|media|meet|melbourne|meme|memorial|men|menu|meo|metlife|mg|mh|miami|microsoft|mil|mini|mk|ml|mlb|mls|mm|mma|mn|mo|mobi|mobily|moda|moe|moi|mom|monash|money|montblanc|mormon|mortgage|moscow|motorcycles|mov|movie|movistar|mp|mq|mr|ms|mt|mtn|mtpc|mtr|mu|museum|mutual|mutuelle|mv|mw|mx|my|mz|na|nadex|nagoya|name|natura|navy|nc|ne|nec|net|netbank|netflix|network|neustar|new|news|next|nextdirect|nexus|nf|ng|ngo|nhk|ni|nico|nikon|ninja|nissan|nissay|nl|no|nokia|northwesternmutual|norton|now|nowruz|nowtv|np|nr|nra|nrw|ntt|nu|nyc|nz|obi|office|okinawa|olayan|olayangroup|ollo|om|omega|one|ong|onl|online|ooo|oracle|orange|org|organic|origins|osaka|otsuka|ott|ovh|pa|page|pamperedchef|panerai|paris|pars|partners|parts|party|passagens|pccw|pe|pet|pf|pg|ph|pharmacy|philips|photo|photography|photos|physio|piaget|pics|pictet|pictures|pid|pin|ping|pink|pioneer|pizza|pk|pl|place|play|playstation|plumbing|plus|pm|pn|pohl|poker|porn|post|pr|praxi|press|prime|pro|prod|productions|prof|progressive|promo|properties|property|protection|ps|pt|pub|pw|pwc|py|qa|qpon|quebec|quest|racing|re|read|realestate|realtor|realty|recipes|red|redstone|redumbrella|rehab|reise|reisen|reit|ren|rent|rentals|repair|report|republican|rest|restaurant|review|reviews|rexroth|rich|richardli|ricoh|rio|rip|ro|rocher|rocks|rodeo|room|rs|rsvp|ru|ruhr|run|rw|rwe|ryukyu|sa|saarland|safe|safety|sakura|sale|salon|samsung|sandvik|sandvikcoromant|sanofi|sap|sapo|sarl|sas|save|saxo|sb|sbi|sbs|sc|sca|scb|schaeffler|schmidt|scholarships|school|schule|schwarz|science|scor|scot|sd|se|seat|security|seek|select|sener|services|seven|sew|sex|sexy|sfr|sg|sh|sharp|shaw|shell|shia|shiksha|shoes|shop|shouji|show|shriram|si|silk|sina|singles|site|sj|sk|ski|skin|sky|skype|sl|sm|smile|sn|sncf|so|soccer|social|softbank|software|sohu|solar|solutions|song|sony|soy|space|spiegel|spot|spreadbetting|sr|srl|st|stada|star|starhub|statebank|statefarm|statoil|stc|stcgroup|stockholm|storage|store|stream|studio|study|style|su|sucks|supplies|supply|support|surf|surgery|suzuki|sv|swatch|swiss|sx|sy|sydney|symantec|systems|sz|tab|taipei|talk|taobao|tatamotors|tatar|tattoo|tax|taxi|tc|tci|td|tdk|team|tech|technology|tel|telecity|telefonica|temasek|tennis|teva|tf|tg|th|thd|theater|theatre|tickets|tienda|tiffany|tips|tires|tirol|tj|tk|tl|tm|tmall|tn|to|today|tokyo|tools|top|toray|toshiba|total|tours|town|toyota|toys|tr|trade|trading|training|travel|travelers|travelersinsurance|trust|trv|tt|tube|tui|tunes|tushu|tv|tvs|tw|tz|ua|ubs|ug|uk|unicom|university|uno|uol|ups|us|uy|uz|va|vacations|vana|vc|ve|vegas|ventures|verisign|versicherung|vet|vg|vi|viajes|video|vig|viking|villas|vin|vip|virgin|vision|vista|vistaprint|viva|vlaanderen|vn|vodka|volkswagen|vote|voting|voto|voyage|vu|vuelos|wales|walter|wang|wanggou|warman|watch|watches|weather|weatherchannel|webcam|weber|website|wed|wedding|weibo|weir|wf|whoswho|wien|wiki|williamhill|win|windows|wine|wme|wolterskluwer|work|works|world|ws|wtc|wtf|xbox|xerox|xihuan|xin|xperia|xxx|xyz|yachts|yahoo|yamaxun|yandex|ye|yodobashi|yoga|yokohama|you|youtube|yt|yun|za|zappos|zara|zero|zip|zm|zone|zuerich|zw)$`, 0)
	if err != nil {
		return false, err
	}
	match, err := r.MatchString(tld)
	if err != nil {
		return false, err
	}
	if !match {
		return false, errors.New("TLD is not in iana list")
	}
	return true, nil
}

// HasValidTld checks a domain/url/uri against a given list of TLD from iana
func (d *domainutils) HasValidTld() (bool, error) {
	tld, err := d.ExtractTld()
	if err != nil {
		return false, err
	}
	return d.IsValidTld(tld)
}