Sinyalizasiya bizim a\u015fa\u011f\u0131da t\u0259svir edil\u0259n soket realla\u015fmam\u0131zla s\u0131x ba\u011fl\u0131d\u0131r.<\/li>\n<\/ul>\n\n![\"\u00c7ox](\"\/wp-content\/uploads\/2019\/09\/5e30bc22643f8baecf850053bf69e130.jpg\")
\nOyun i\u00e7ind\u0259ki v\u0259 ana s\u0259hif\u0259d\u0259ki serverl\u0259rin siyah\u0131s\u0131<\/i><\/p>\nSoketl\u0259rin realla\u015fmas\u0131<\/h1>\n
\nM\u00fcmk\u00fcn q\u0259d\u0259r Posix UDP Sockets-a yax\u0131n bir API yaratmaq ist\u0259yirik ki, laz\u0131m olan d\u0259yi\u015fiklikl\u0259rin say\u0131n\u0131 minimuma endir\u0259k.<\/p>\n
Eyni zamanda, \u015f\u0259b\u0259k\u0259 \u00fczr\u0259 \u0259n sad\u0259 m\u0259lumat m\u00fcbadil\u0259si \u00fc\u00e7\u00fcn laz\u0131m olan minimumlar\u0131 realla\u015fd\u0131rmaq ist\u0259yirik.<\/p>\n
M\u0259s\u0259l\u0259n, biz\u0259 real mar\u015frutla\u015fd\u0131rma laz\u0131m deyil: b\u00fct\u00fcn peer-l\u0259r m\u00fc\u0259yy\u0259n bir Firebase veril\u0259nl\u0259r bazas\u0131 instansiyas\u0131 il\u0259 ba\u011fl\u0131 \u00abvirtual LAN\u00bb i\u00e7ind\u0259dir.<\/p>\n
N\u0259tic\u0259d\u0259, biz\u0259 unikal IP \u00fcnvanlar\u0131 laz\u0131m deyil: peer-l\u0259ri unikal \u015f\u0259kild\u0259 tan\u0131maq \u00fc\u00e7\u00fcn unikal Firebase a\u00e7ar d\u0259y\u0259rl\u0259rinin istifad\u0259si kifay\u0259tdir (domen adlar\u0131na b\u0259nz\u0259r \u015f\u0259kild\u0259) v\u0259 h\u0259r peer m\u00fcvafiq a\u00e7ara \u00absaxta\u00bb IP \u00fcnvanlar\u0131 t\u0259yin edir ki, bu da tamamil\u0259 qlobal IP \u00fcnvanlar\u0131n\u0131n ayr\u0131lanmas\u0131n\u0131 aradan qald\u0131r\u0131r, bu is\u0259 \u0259h\u0259miyy\u0259tli bir m\u0259s\u0259l\u0259dir.<\/p>\n
Bizim realla\u015fd\u0131rmal\u0131 oldu\u011fumuz minimal API budur:<\/p>\n
\/\/ Create and destroy a socket\nint socket();\nint close(int fd);\n\/\/ Bind a socket to a port, and publish it on Firebase\nint bind(int fd, AddrInfo* addr);\n\/\/ Send a packet. This lazily create a WebRTC connection to the \n\/\/ peer when necessary\nint sendto(int fd, uint8_t* buf, int len, const AddrInfo* addr);\n\/\/ Receive the packets destined to this socket\nint recvfrom(int fd, uint8_t* buf, int len, AddrInfo* addr);\n\/\/ Be notified when new packets arrived\nint recvCallback(Callback cb);\n\/\/ Obtain a local ip address for this peer key\nuint32_t resolve(client::String* key);\n\/\/ Get the peer key for this ip\nString* reverseResolve(uint32_t addr);\n\/\/ Get the local peer key\nString* local_key();\n\/\/ Initialize the library with the given Firebase database and \n\/\/ WebRTc connection options\nvoid init(client::FirebaseConfig* fb, client::RTCConfiguration* ice);<\/code><\/pre>\n\nAPI sad\u0259dir v\u0259 Posix Sockets API-y\u0259 b\u0259nz\u0259yir, lakin b\u0259zi m\u00fch\u00fcm f\u0259rqlilikl\u0259r\u0259 malikdir: geri \u00e7a\u011f\u0131rma qeydiyyat\u0131, yerli IP-l\u0259rin t\u0259yin edilm\u0259si v\u0259 \"t\u0259nb\u0259l\" ba\u011flant\u0131<\/strong>.<\/p>\nGeri \u00e7a\u011f\u0131rma qeydiyyat\u0131<\/h2>\n
\n\u018fg\u0259r \u0259sas proqram bloklanmam\u0131\u015f giri\u015f-\u00e7\u0131x\u0131\u015f istifad\u0259 edirs\u0259, veb brauzerind\u0259 i\u015f\u0259 salmaq \u00fc\u00e7\u00fcn kodu yenid\u0259n t\u0259\u015fkil etm\u0259k laz\u0131md\u0131r.<\/p>\n
Bunun s\u0259b\u0259bi budur ki, brauzerd\u0259ki hadis\u0259 d\u00f6ng\u00fcs\u00fc proqramdan (JavaScript v\u0259 ya WebAssembly olsun) gizlidir.<\/p>\n
T\u0259bi\u0259t m\u00fchitind\u0259 kodu bel\u0259 yaza bilirik<\/p>\n
while(running) {\n select(...); \/\/ I\/O hadis\u0259l\u0259rini g\u00f6zl\u0259yin\n while(true) {\n int r = readfrom(...); \/\/ oxuma\u011fa \u00e7al\u0131\u015f\u0131n\n if (r < 0 && errno == EWOULDBLOCK) \/\/ art\u0131q m\u0259lumat yoxdur\n break;\n ...\n }\n ...\n}<\/code><\/pre>\n\n\u018fg\u0259r hadis\u0259 d\u00f6ng\u00fcs\u00fc bizd\u0259n gizlidirs\u0259, onu bel\u0259 bir \u015fey\u0259 \u00e7evirm\u0259liyik:<\/p>\n
auto cb = []() { \/\/ yeni m\u0259lumat m\u00f6vcud olduqda \u00e7a\u011f\u0131r\u0131lacaq\n while(true) {\n int r = readfrom(...); \/\/ oxuma\u011fa \u00e7al\u0131\u015f\u0131n\n if (r < 0 && errno == EWOULDBLOCK) \/\/ art\u0131q m\u0259lumat yoxdur\n break;\n ...\n }\n ...\n};\nrecvCallback(cb); \/\/ geri \u00e7a\u011f\u0131rman\u0131 qeydiyyatdan ke\u00e7irin<\/code><\/pre>\n<\/p>\n
Yerli IP-l\u0259rin t\u0259yini<\/h2>\n
\nBizim \"\u015f\u0259b\u0259k\u0259mizd\u0259ki\" d\u00fcy\u00fcnl\u0259r IP \u00fcnvanlar\u0131 deyil, Firebase a\u00e7arlar\u0131d\u0131r (bunlar bel\u0259 g\u00f6r\u00fcn\u0259n s\u0259tirl\u0259rdir: -LmEC50PYZLCiCP-vqde<\/code> ).<\/p>\nBu, rahatd\u0131r, \u00e7\u00fcnki IP-l\u0259ri t\u0259yin etm\u0259k v\u0259 onlar\u0131n unikal oldu\u011funu yoxlamaq \u00fc\u00e7\u00fcn mexanizm\u0259 ehtiyac yoxdur (h\u0259m\u00e7inin m\u00fc\u015ft\u0259ri s\u00f6nd\u00fcr\u00fcld\u00fckd\u0259n sonra onlar\u0131n utilizasiyas\u0131), lakin tez-tez peer-l\u0259ri say\u0131sal d\u0259y\u0259r \u0259sas\u0131nda identifikasiya etm\u0259k laz\u0131md\u0131r.<\/p>\n
Bunun \u00fc\u00e7\u00fcn funksiyalar istifad\u0259 olunur resolve<\/code> v\u0259 reverseResolve<\/code>: t\u0259tbiq bir \u015f\u0259kild\u0259 a\u00e7ar\u0131n s\u0259tir d\u0259y\u0259rini al\u0131r (istifad\u0259\u00e7i daxil etm\u0259si il\u0259 v\u0259 ya master server vasit\u0259sil\u0259) v\u0259 bunu daxili istifad\u0259 \u00fc\u00e7\u00fcn IP \u00fcnvan\u0131na \u00e7evir\u0259 bilir. API-nin qalan hiss\u0259si d\u0259 sad\u0259lik \u00fc\u00e7\u00fcn s\u0259tir \u0259v\u0259zin\u0259 bu d\u0259y\u0259ri al\u0131r.<\/p>\nBu, DNS axtar\u0131\u015f\u0131na b\u0259nz\u0259yir, yaln\u0131z m\u00fc\u015ft\u0259ri t\u0259r\u0259find\u0259 yerin\u0259 yetirilir.<\/p>\n
Y\u0259ni, IP \u00fcnvanlar\u0131 f\u0259rqli m\u00fc\u015ft\u0259ril\u0259r \u00fc\u00e7\u00fcn ortaq ola bilm\u0259z, v\u0259 \u0259g\u0259r qlobal bir identifikator laz\u0131md\u0131rsa, onu ba\u015fqa \u00fcsulla generasiya etm\u0259liyik.<\/p>\n
T\u0259nb\u0259l ba\u011flant\u0131<\/h2>\n
\nUDP \u00fc\u00e7\u00fcn ba\u011flant\u0131 t\u0259l\u0259b olunmur, lakin g\u00f6rd\u00fcy\u00fcm\u00fcz kimi, iki peer aras\u0131nda m\u0259lumat m\u00fcbadil\u0259sin\u0259 ba\u015flamaq \u00fc\u00e7\u00fcn WebRTC uzun bir ba\u011flant\u0131 prosesi t\u0259l\u0259b edir.<\/p>\n
Eyni abstraksiya s\u0259viyy\u0259sini t\u0259min etm\u0259k ist\u0259yiriks\u0259, (sendto<\/code>\/recvfrom<\/code> arbitrary peers il\u0259 \u0259vv\u0259lc\u0259d\u0259n ba\u011flant\u0131 olmadan), API daxilind\u0259 \"t\u0259nb\u0259l\" (\u0259zil\u0259c\u0259k) ba\u011flant\u0131 h\u0259yata ke\u00e7irm\u0259liyik.<\/p>\n\u0130ki \"server\" v\u0259 \"m\u00fc\u015ft\u0259ri\" aras\u0131nda adi m\u0259lumat m\u00fcbadil\u0259si zaman\u0131 ba\u015f ver\u0259n budur v\u0259 kitabxanam\u0131z\u0131n yerin\u0259 yetirm\u0259si laz\u0131m olan\u0131:<\/p>\n
\n- Server \u00e7a\u011f\u0131r\u0131r
bind()<\/code>, \u0259m\u0259liyyat sistemin\u0259 g\u00f6st\u0259rm\u0259k \u00fc\u00e7\u00fcn ki, m\u00fc\u0259yy\u0259n bir portda paketl\u0259ri q\u0259bul etm\u0259k ist\u0259yir.<\/li>\n<\/ul>\n\nBunun \u0259v\u0259zin\u0259 biz server a\u00e7ar\u0131 alt\u0131nda Firebase-d\u0259 a\u00e7\u0131q portu yay\u0131mlayaca\u011f\u0131q v\u0259 onun alt\u0131ndan hadis\u0259l\u0259ri dinl\u0259y\u0259c\u0259yik.<\/p>\n
\n- Server \u00e7a\u011f\u0131r\u0131r
recvfrom()<\/code>, bu porta ist\u0259nil\u0259n ev sahibl\u0259rind\u0259n g\u0259l\u0259n paketl\u0259ri q\u0259bul ed\u0259r\u0259k.<\/li>\n<\/ul>\n\nBizim halda, bu porta g\u00f6nd\u0259ril\u0259n paketl\u0259rin g\u0259l\u0259n n\u00f6vb\u0259sini yoxlamaq laz\u0131md\u0131r.<\/p>\n
H\u0259r bir portun \u00f6z n\u00f6vb\u0259si var v\u0259 biz WebRTC datagramlar\u0131na giri\u015f v\u0259 \u00e7\u0131x\u0131\u015f portlar\u0131n\u0131 \u0259lav\u0259 edirik ki, yeni paket g\u0259ldikd\u0259 hans\u0131 n\u00f6vb\u0259y\u0259 y\u00f6nl\u0259ndiril\u0259c\u0259yini bil\u0259k.<\/p>\n
\u00c7a\u011fr\u0131 bloklanm\u0131r, ona g\u00f6r\u0259 d\u0259 paket olmad\u0131qda sad\u0259c\u0259 -1 qaytar\u0131r\u0131q v\u0259 sor\u011fu edirik. errno=EWOULDBLOCK<\/code>.<\/p>\n\n- M\u00fc\u015ft\u0259ri xarici vasit\u0259l\u0259rl\u0259 serverin IP v\u0259 portunu al\u0131r v\u0259 \u00e7a\u011f\u0131r\u0131r.
sendto()<\/code>. H\u0259m\u00e7inin, burada daxili bir \u00e7a\u011f\u0131r\u0131\u015f h\u0259yata ke\u00e7irilir. bind()<\/code>, buna g\u00f6r\u0259 d\u0259 sonrak\u0131 recvfrom()<\/code> cavab alacaq, a\u00e7\u0131q \u015f\u0259kild\u0259 bind yerin\u0259 yetirilm\u0259d\u0259n.<\/li>\n<\/ul>\n\nBizim v\u0259ziyy\u0259td\u0259 m\u00fc\u015ft\u0259ri xarici \u015f\u0259kild\u0259 a\u00e7ar simvolunu al\u0131r v\u0259 funksiyas\u0131 il\u0259 istifad\u0259 edir. resolve()<\/code> IP \u00fcnvan\u0131n\u0131 \u0259ld\u0259 etm\u0259k \u00fc\u00e7\u00fcn.<\/p>\nBu m\u0259rh\u0259l\u0259d\u0259, \u0259g\u0259r iki pir h\u0259l\u0259 bir-birin\u0259 qo\u015fulmay\u0131bsa, WebRTC \"\u0259ll\u0259 s\u0131xma\" prosesi ba\u015flay\u0131r. Eyni pir \u00fc\u00e7\u00fcn m\u00fcxt\u0259lif portlara qo\u015fulmalar eyni WebRTC DataChannel istifad\u0259 edir.<\/p>\n
H\u0259m\u00e7inin biz dolay\u0131 bir bind()<\/code>yerin\u0259 yetiririk ki, server g\u0259l\u0259c\u0259kd\u0259 ola bil\u0259c\u0259k ba\u011flanma s\u0259b\u0259bind\u0259n qo\u015fulman\u0131 b\u0259rpa etsin. sendto()<\/code> Server m\u00fc\u015ft\u0259rinin qo\u015fuldu\u011funu bildirir, m\u00fc\u015ft\u0259ri \u00f6z SDP t\u0259klifini serverin portu m\u0259lumatlar\u0131 il\u0259 Firebase-d\u0259 yazd\u0131\u011f\u0131 zaman, server d\u0259 orada \u00f6z cavab\u0131n\u0131 verir.<\/p>\nA\u015fa\u011f\u0131dak\u0131 c\u0259dv\u0259ld\u0259 m\u00fc\u015ft\u0259ri-server aras\u0131nda mesajlar\u0131n h\u0259r\u0259k\u0259tinin bir n\u00fcmun\u0259si g\u00f6st\u0259rilir.<\/p>\n
\nM\u00fc\u015ft\u0259ri v\u0259 server aras\u0131nda qo\u015fulma m\u0259rh\u0259l\u0259sinin tam sxemi.<\/p>\n
![\"\u00c7ox](\"\/wp-content\/uploads\/2019\/09\/7dc48e816c09e33daf28c307cad0c258.jpg\")
\n\u018fg\u0259r sona q\u0259d\u0259r oxudunuzsa, y\u0259qin ki, n\u0259z\u0259riyy\u0259ni i\u015f ba\u015f\u0131nda g\u00f6rm\u0259k ist\u0259yirsiniz. Oyun oynamaq olar.<\/i><\/p>\nN\u0259tic\u0259<\/h1>\n
\nteeworlds.leaningtech.com