???????????????? ?? WWW ? HTTP

1
???????????????? ?? WWW ? HTTP
??????? ?????
?????????? ???????? ?? ?????????? ?? ???????
academy.devbg.org
2
??????????

1. ????? ? WWW?
2. ?????????? ?? WWW URL, HTML, HTTP
3. ?????????? HTTP
4. HTTP ??????
5. HTTP ????????
6. Cookies

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????? ? WWW?
??????????? ?? World Wide Web
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????? ? WWW?

• WWW World Wide Web Web ???
• ???????? ????????????? ???????????? ? ????????
• ?????? ? ???????? (???? E-mail, DNS, ...)
• ????????? ????????? (? ????? ???????) ???????????
  ?? ???????? ??? ???????
• ???????? ???? ?????????? ????????? ???? HTTP,
  HTTPS ? FTP ?? ?????? URL
• ??? ????????? ??????????? ??? ??????????
• ??? ?????????? ???????? ??? ????????

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?????????? ?? WWW

• ?????????? ??????????
• Internet ?????????? ?????? ?? ????? ??
  ??????????? TCP ? HTTP
• ??????? (??? ????????) ???????? ???
  ???????????? Internet Explorer, Mozilla,
• ??? ??????? Apache, IIS, Tomcat
• ?????????? ??????????
• Hyper Text Transfer Protocol (HTTP)
• Hyper Text Markup Language (HTML)
• Uniform Resource Locator (URL)
• Uniform Resource Identifiers (URIs)

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?????????????? ?? WWW

• ????????? ????????? ??? ??????? ?? ?? ?????
  ??????? ?? ??? ????????? ?? HTTP
• ????????? ???? ???????? URL ?????
• ????????? ?????? ????????? ??????
• ??? ?????? ??? ? ????????? ?? ??????
• ??? ?????????? ?? ??????? ??? WWW
• ??????? ?? ?? HTML ?????, ???????, ????????, ????
  ? ????? ??????? (???????)
• ??? ???????
• ??? ????????? ?? ??????????? ?? ??? ????????

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?????????????? ?? WWW (2)

• ?????????? ??????? ??????? (render) ???
  ??????????, ??????? ?? ??? ???????
• ?????????? ?? ???????? ?? ????? HTML (Hyper Text
  Markup Language)
• ?????????? ???????? ?????, ??????? ? ????
• HTML ?????????? ????? ?? ???????? ?????-?????? ??
  ????????? ??? ????? ????????
• ?????? ??????? ?? WWW ?????? ????? ??????????
  ??????? ?????????
• TCP/IP, DNS, HTTP,
• ?????????? HTTP ? ????????????? ?? WWW

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??????? ?????????? ?? WWW URL

• Uniform Resource Locator (URL)
• ????? ?? ???????? ?????? ??? WWW, ????.
• ???????????? ?????????? ???
• ???????? ?? ?????? ?? ??????? (http, ftp, https,
  ...)
• ??? ?? ??????? ??? IP ????? (????????
  academy.devbg.org)
• ??? ?? ??????? ? ??? (????., index.php)
• ????????? (????. ?id27langen)

http//academy.devbg.org/index.php
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??????? ?????????? ?? WWW HTML

• Hyper Text Markup Language (HTML)
• ?????????? ????? ? ???????? ? ???????????
• ???????????? ?? ? ?? ??????? ?? ??????????
• ????? ?? ????????? ? ??????????
• HTML ??????????? ?? ?????? ????? ? ??????
• ????? ?? ?????? ??????????? ?? ??????
• ???????? ?? ??????????? ? HTML ?????????
• ??? ????????
• HTML ????, ????????? ???????? ? ????? ???????
  (?????????? ?? ???????)

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HTML ??????
lthtmlgt ltheadgtlttitlegtExample HTMLlt/titlegtlt/headgt
ltbodygt lth1gtHeading 1lt/h1gt lth2gtSub
heading 2lt/h2gt lth3gtSub heading 3lt/h3gt
ltpgtThis is my first paragraphlt/pgt ltpgtThis is
my second paragraphlt/pgt lta href"http//academ
y.devbg.org"gtltimg src"NASD-logo.png"
border"0"gtlt/agt ltdiv align"center"
style"backgroundskyblue"gt This is a
divlt/divgt lt/bodygt lt/htmlgt
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HTML ??????
lthtmlgt ltheadgtlttitlegtExample HTMLlt/titlegtlt/headgt
ltbodygt lth1gtHeading 1lt/h1gt lth2gtSub
heading 2lt/h2gt lth3gtSub heading 3lt/h3gt
ltpgtThis is my first paragraphlt/pgt ltpgtThis is
my second paragraphlt/pgt lta href"http//academ
y.devbg.org"gtltimg src"NASD-logo.png"
border"0"gtlt/agt ltdiv align"center"
style"backgroundskyblue"gt This is a
divlt/divgt lt/bodygt lt/htmlgt
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??????? ?????????? ?? WWW HTTP

• Hyper Text Transfer Protocol (HTTP)
• ???????? ?? ?????? ?? ??? ??????? ????? ???
  ?????? ? ??? ??????
• ????? ???????? ?? HTTP
• ????? ?????? ???????
• ???????? ?????????? ???? URL
• ?? ???????? ????????? (stateless)
• ?????? ??????? ? ????????? ?? ???
• ??????? ??????

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?????????? HTTP
??? HTTP ???????
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HTTP ?????? ? ????????

• ????????? ??????????
• ???????? ??? ???????
• ???? ??????
• ??????? ??????

• ???????? ??????????
• ??? ??????
• ????? ??????? ??????
• ?????????? ??????

GET /index.html
"Welcome to our Web site!"
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?????? Hyper Text Transfer Protocol
HTTP ??????
GET /courses/archive/spring06/cos461/
HTTP/1.1 Host www.cs.princeton.edu User-Agent
Mozilla/4.03 ltCRLFgt
???????? ??? ??????? ???? ?? ?????? ?? ????????
HTTP ???????
HTTP/1.1 200 OK Date Mon, 6 Feb 2006 130903
GMT Server Netscape-Enterprise/3.5.1 Last-Modifie
d Mon, 6 Feb 2006 111223 GMT2 Content-Length
54 ltCRLFgt lthtmlgtlttitlegtHellolt/titlegt Welcome to
our sitelt/htmlgt
???????? ??? ??????? ???? ?? ?????? ?? ????????
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HTTP ??????

• HTTP ???????? ?? ??????? ?? ?????? ??
• ??? ?? ???????? (request line)
• ????? ?? ???????? (GET, POST, HEAD, PUT, ...),
  ?????? ? ?????? ?? HTTP ?????????
• ?????? ?? ????????
• ?????????? ???????? ????????? ? ?????????
• ????
• ??????? ?????, ???? ?? ? ??????

ltrequest methodgt ltresourcegt HTTP/ltversiongt ltheader
sgt ltempty linegt ltbodygt
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HTTP GET ?????? ??????
?????? ?? HTTP GET ??????
GET /InetJava-2002-program.html HTTP/1.1 Host
inetjava.sourceforge.net Accept
/ Accept-Language bg Accept-Encoding gzip,
deflate User-Agent Mozilla/4.0(compatibleMSIE
6.0 Windows NT 5.0) Connection
Keep-Alive Cache-Control no-cache ltCRLFgt
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HTTP POST ?????? ??????
?????? ?? HTTP POST ??????
POST /webmail/login.phtml HTTP/1.1 Host
www.abv.bg Accept / Accept-Language
bg Accept-Encoding gzip, deflate User-Agent
Mozilla/4.0(compatibleMSIE 6.0 Windows NT
5.0) Connection Keep-Alive Cache-Control
no-cache Content-Length 59 ltCRLFgt LOGIN_USERbori
s DOMAIN_NAMEabv.bg LOGIN_PASStajnamajna ltCRLFgt
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HTTP ??????? GET ?????? ??????
?????? ?? HTTP ??????? GET ??????
GET /courses/archive/spring06/cos461/
HTTP/1.1 Host www.cs.princeton.edu User-Agent
Mozilla/4.03 If-Modified-Since Mon, 6 Feb 2006
111223 GMT ltCRLFgt

• ????? ??????? ???? ??? ? ??? ??????????? ??
  ???????
• ????????? ?? ??????? (???? ????????)
• ???????? ????? ??????? 304 Not Modified ???
  ???????? ?? ? ????????
• ??? 200 OK ? ?????????? ?????? ?? ???????

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HTTP ???????

• ????????? ?? ???????? ?? ?????? ??
• ?????? ??? ?????? ?? HTTP ?????????, ??????
  ???, ??????????? ?????
• ?????? ?? ???????? ??????????? ?????????
• ???? ?????????? ?? ???????? (????????? ??????)

HTTP/ltversiongt ltstatus codegt ltstatus
textgt ltheadersgt ltempty linegt ltresponse body -
requested resourcegt
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HTTP ??????? ??????
?????? ?? HTTP ??????? ?? ???????
HTTP/1.1 200 OK Date Sat, 10 Aug 2002 160918
GMT Server Apache/1.3.9 (Win32) Accept-Ranges
bytes Content-Length 73 Content-Type
text/html lthtmlgt ltheadgt lttitlegt Test lt/titlegt
lt/headgt Test HTML page. lt/htmlgt

• ??? ???????? ????? ????????? ?????? ?????? ?
  ????????? ?? ????

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HTTP ??????? ??????
?????? ?? HTTP ??????? ? ??? ?? ??????
HTTP/1.1 404 Not Found Date Sat, 10 Aug 2002
162017 GMT Server Apache/1.3.9
(Win32) Connection close Content-Type
text/html ltHTMLgtltHEADgt ltTITLEgt404 Not
Foundlt/TITLEgt lt/HEADgtltBODYgt ltH1gtNot
Foundlt/H1gt The requested URL /img/nakov.gif was
not found on this server.ltPgt ltHRgtltADDRESSgtApache/1
.3.9 Server at test Port 80lt/ADDRESSgt lt/BODYgtlt/HTM
Lgt
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?????? ?? HTTP ????????

• ??-????? ?????? ?? HTTP ????????
• GET ????? ?????? ?? ???????, ??????????
  ????????? ???????? ??? ?????? (??? ?????????
  ??????????)
• HEAD ????? ??????????? ?? ????? ?????? (????
  ???????? ?? ????????)
• POST ???????? ??????, ??????? ????? ?? ?????????
  ??? ???????? ??? ?????? ?? ???????

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HTTP ?????? ?? ????????

• ??????? ?????? ?? HTTP ????????
• 1xx ?????????? (????., 100 Continue)
• 2xx ????? (????., 200 OK)
• 3xx ???????????? (????., 304 Not Modified,
  "302 Found")
• 4xx ?????? ??? ??????? (????., 404 Not Found)
• 5xx ?????? ?? ??????? (????., 503 Service
  Unavailable)
• "302 Found" ?? ???????? ?? ????????????
  (redirect) ?? ??? ???????? ??? ???? URL

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Cookies

• Cookie (????)
• ????? ???? ????? ????????? ?? ??????? ? ?????????
  ??????? ? ??? ????????
• ???????? ?? ? ?????? ?? ?????? ?????? ??? ?????
  ??? ??????

??????
??????? Set-Cookie XYZ
???????? ?????? Cookie XYZ
26
???????????????? ?? WWW ? HTTP

• ????????