A brief historical overview of how Perl 6 was used to make web sites in the past, and how you can use it today to run the Plack/PSGI-based site.

1. Perl 6
in Production

2. 15 years of development

3. Ready December 2015

4. This December

5. Start using?

6. Perl 6 for
Web
Development

7. What’s wrong
with Perl 6?

8. What’s wrong
with today’s Perl 6?

9. Not that it is too late

10. Rather that it is too mature

12. Lots of blog posts

13. Lots of documentation

14. Lots of code examples

15. Lots of errors

16. Everything
has been googled

17. Not easy to find how
this or that works

18. Most of code examples
and modules are outdated

19. Outdated before
the release!

20. Nothing works!

21. Even if it used to work

22. ===SORRY!===
Error
while
compiling
!
Undeclared
routine:
eval
used
at
line
7.
Did
you
mean
'val'?

23. ===SORRY!===
Error
while
compiling
!
Undeclared
routine:
eval
used
at
line
7.
Did
you
mean
'val'?

24. (useEVAL)

25. A bit of history

26. 2000
Perl 6 announced

27. First implementations

28. Parrot

29. Parrot with Perl 6 compiler

30. Pugs

31. Pugs, the Perl 6 compiler

32. Rakudo

33. Rakudo Star

34. Past

35. 2004
real.perl6.ru
http://web.archive.org/web/*/real.perl6.ru

37. Some examples
of the code of 2004

38. Reading
environment variables

39. my
@keys
=
('SERVER_NAME',
'REMOTE_ADDR',
'HTTP_USER_AGENT');
!
my
$key;
foreach
$key
(@keys){
print
"$key=%ENV{$key}<br
/>n";
}

40. Looks almost like Perl 5

41. my
@keys
=
('SERVER_NAME',
'REMOTE_ADDR',
'HTTP_USER_AGENT');
!
my
$key;
foreach
$key
(@keys){
print
"$key=%ENV{$key}<br
/>n";
}

42. You could learn Perl 6
in a few hours

43. Setting/getting cookies

44. print
"Content-­‐Type:
text/htmln"
print
'Set-­‐Cookie:
cookie-­‐
name=test-­‐value;
path=/;nn';
!
print
%ENV{'HTTP_COOKIE'};

45. URL GET parameters

46. read_params
(
%ENV{'QUERY_STRING'},
@params_key,
@params_value
);

47. sub
read_params
($query,
@params_key,
@params_value){
my
$pos
=
0;
loop
(my
$c
=
0;
1;
$c++)
{
my
$newpos
=
index
($query,
'&',
$pos);
my
@keyvalue;
my
$pair
=
substr
($query,
$pos,
$newpos
==
-­‐1
??
length
($query)
::
$newpos
-­‐
$pos);
split_pair
($pair,
@keyvalue);
@params_key[$c]
=
@keyvalue[0];
@params_value[$c]
=
@keyvalue[1];
last
if
$newpos
==
-­‐1;
$pos
=
$newpos
+
1;
}
}

48. sub
read_params
($query,
@params_key,
@params_value){
my
$pos
=
0;
loop
(my
$c
=
0;
1;
$c++)
{
my
$newpos
=
index
($query,
'&',
$pos);
my
@keyvalue;
my
$pair
=
substr
($query,
$pos,
$newpos
==
-­‐1
??
length
($query)
::
$newpos
-­‐
$pos);
split_pair
($pair,
@keyvalue);
@params_key[$c]
=
@keyvalue[0];
@params_value[$c]
=
@keyvalue[1];
last
if
$newpos
==
-­‐1;
$pos
=
$newpos
+
1;
}
}

49. sub
split_pair
($pair,
@keyvalue){
my
$pos
=
index
($pair,
'=');
if
($pos
==
-­‐1){
@keyvalue[0]
=
$pair;
@keyvalue[1]
=
'';
}
else{
@keyvalue[0]
=
substr
($pair,
0,
$pos);
@keyvalue[1]
=
substr
($pair,
$pos
+
1);
}
}

50. URL GET parameters
using hashes

51. sub
params2hash
(%params,
@params_key,
@params_value){
for
0
..
@params_key
-­‐>
$c{
%params{@params_key[$c]}
=
@params_value[$c];
}
}
!
read_params
(%ENV{'QUERY_STRING'},
@params_key,
@params_value);
my
%params;
params2hash
(%params,
@params_key,
@params_value);

52. To speed it up

53. Compiling to bytecode

54. .pasm
.imc

55. 100% compatible

56. 2007/2008
november-wiki.org
https://github.com/viklund/november

58. November::CGI

59. class
November::CGI
{
has
%.params;
has
%.cookie;
has
@.keywords;
has
November::URI
$.uri;

60. self.parse_params(%*ENV<QUERY_STRING>
//
'');

61. has
$!crlf
=
"x[0D]x[0A]";
.
.
.
!
print
"Status:
$status$!crlf";
print
"Location:
$uri";
print
"$!crlf$!crlf";

62. has
$!crlf
=
"x[0D]x[0A]";
.
.
.
!
print
"Status:
$status$!crlf";
print
"Location:
$uri";
print
"$!crlf$!crlf";
Compare
https://p6weekly.wordpress.com/2015/11/09/2015-46-
production-today/

63. Smartmatch and junctions

64. method
add_param
(
Str
$key,
$value
)
{
if
%.params{$key}
:exists
{
#
RAKUDO:
~~
Scalar
if
%.params{$key}
~~
Str
|
Int
{
my
$old_param
=
%.params{$key};
%!params{$key}
=
[
$old_param,
$value
];
}
elsif
%.params{$key}
~~
Array
{
%!params{$key}.push(
$value
);
}
}
else
{
%!params{$key}
=
$value;
}
}

65. Compiler incompatibilities

66. method
add_param
(
Str
$key,
$value
)
{
if
%.params{$key}
:exists
{
#
RAKUDO:
~~
Scalar
if
%.params{$key}
~~
Str
|
Int
{
my
$old_param
=
%.params{$key};
%!params{$key}
=
[
$old_param,
$value
];
}
elsif
%.params{$key}
~~
Array
{
%!params{$key}.push(
$value
);
}
}
else
{
%!params{$key}
=
$value;
}
}

67. if
%*ENV<MODPERL6>
{
my
$r
=
Apache::RequestRec.new();
my
$len
=
$r.read($input,
%*ENV<CONTENT_LENGTH>);
}
else
{
#
Maybe
check
content_length
here
#
and
only
take
that
many
bytes?
$input
=
$*IN.slurp;
}
!

68. (I never managed
to install mod_parrot)

69. Grammar for URL parsing

70. grammar
November::URI::Grammar
{
token
TOP
{
^
[<scheme>
':']?
[
'//'
<authority>]?
<path>
['?'
<query>]?
['#'
<fragment>]?
$
};
token
scheme
{
<-­‐[:/&?#]>+
};
token
authority
{
<host>
[':'
<port>]?
};
token
host
{
<-­‐[/&?#:]>*
};
token
port
{
(d**1..5)
<?{
$0
<
2
**
16
}>
<!before
d>
};
token
path
{
<slash>?
[
<chunk>
'/'?]*
};
token
slash
{
'/'
};
token
chunk
{
<-­‐[/?#]>+
};
token
query
{
<-­‐[#]>*
};
token
fragment
{
.*
};
}

71. #
Official
regexp
(p5):
#
my($scheme,
$authority,
$path,
$query,
$fragment)
=
#
$uri
=~
m/
#
(?:([^:/?#]+):)?
#
(?://([^/?#]*))?
#
([^?#]*)
#
(?:?([^#]*))?
#
(?:#(.*))?
#
/x;

72. Not like Perl 5 any more :-)

73. 2011
Plackdo
https://github.com/lopnor/p6-plackdo

74. Plack-like web interface
on Perl 6

75. my
$app
=
sub
(%env)
{
return
(
200,
[
Content-­‐Type
=>
'text/plain',
Content-­‐Length
=>
%env.perl.bytes,
],
[
%env.perl
]
);
};
HTTP status code

76. my
$app
=
sub
(%env)
{
return
(
200,
[
Content-­‐Type
=>
'text/plain',
Content-­‐Length
=>
%env.perl.bytes,
],
[
%env.perl
]
);
};
HTTP headers

77. my
$app
=
sub
(%env)
{
return
(
200,
[
Content-­‐Type
=>
'text/plain',
Content-­‐Length
=>
%env.perl.bytes,
],
[
%env.perl
]
);
};
Response body

78. my
$builder
=
Plackdo::Builder.new;
$builder.add_middleware(
Plackdo::Middleware::XFramework.new(
framework
=>
'foobar')
);
$builder.to_app($app);

79. ~2014
wee6
https://github.com/vti/wee6

80. Present

81. Rakudo Star
http://rakudo.org

82. +

83. modules.perl6.org

84. Installing Rakudo*

85. perl
Configure.pl
-­‐-­‐backend=moar
-­‐-­‐gen-­‐moar
!
make
!
make
install

86. MoarVM
http://moarvm.org

87. Managing modules

88. “Ecosystem”
https://github.com/perl6/ecosystem

90. Panda
!
for installing Perl 6 modules

91. modules/panda/bootstrap.pl

92. panda
install
Module::X

93. Distribution modules live in
install/share/perl6/lib

94. Panda puts modules to
install/share/perl6/site

95. BTW,
Rakudo’s “make install”
compiles modules
to .moarvm

96. OK, Perl.
Let’s build a web server

98. HTTP::Easy
Core’s

99. HTTP::Easy::PSGI
Core’s

100. use
HTTP::Easy::PSGI;

101. my
$http
=
HTTP::Easy::PSGI.new(
:port(8080)
);

102. my
$app
=
sub
(%env)
{
.
.
.
}

103. my
$app
=
sub
(%env)
{
.
.
.
}
!
$http.handle($app);

104. my
$app
=
sub
(%env)
{
return
[
200,
[
'Content-­‐Type'
=>
'text/plain'
],
[
'Hello,
World!’
]
];
}

105. use
HTTP::Easy::PSGI;
my
$http
=
HTTP::Easy::PSGI.new(:port(8080));
!
my
$app
=
sub
(%env)
{
my
$name
=
%env<QUERY_STRING>
||
"World";
return
[
200,
[
'Content-­‐Type'
=>
'text/plain'
],
[
"Hello
$name"
]
];
}
!

106. !
Web::App module set
Explore

107. Bailador

108. Bailador
(Dancer)

109. Available in the Rakudo*
distribution

110. (Does not instantly work
in the 2015.09 distribution)

111. use
Bailador;

112. use
Bailador;
!
get
'/'
=>
sub
{
!
}

113. use
Bailador;
!
get
'/'
=>
sub
{
return
"Hin";
}
!

114. use
Bailador;
!
get
'/'
=>
sub
{
return
"Hin";
}
!
baile;

115. use
Bailador;
!
get
'/'
=>
sub
{
"Hin"
}
!
baile;

116. $
perl6
test.pl
!
Entering
the
development
dance
floor:
http://0.0.0.0:3000
[2015-­‐11-­‐17T13:41:08Z]
Started
HTTP
server.

117. Started…
!
Then open it in a browser

118. Method
'send'
not
found
for
invocant
of
class
'IO::Socket::INET'
in
method
run
at
/home/ash/p/
rakudo-­‐star-­‐2015.09/install/share/
perl6/lib/HTTP/Easy.pm6:193
in
sub
baile
at
/home/ash/p/
rakudo-­‐star-­‐2015.09/install/share/
perl6/lib/Bailador.pm:153
in
block
<unit>
at
test.pl:8

119. Update HTTP::Easy
using panda

120. git
clone
...
panda
install
./Bailador

121. !
-­‐
connection.send($res.Str);
!
+
connection.print($res.Str);

122. use
Bailador;
!
get
'/'
=>
sub
{
return
"Hin";
}
!
get
'/hello/:name'
=>
sub
($name)
{
return
"Hi,
$namen";
}
!
baile;

123. use
Bailador;
!
get
'/'
=>
sub
{
return
"Hin";
}
!
get
'/hello/:name'
=>
sub
($name)
{
return
"Hi,
$namen";
}
!
baile;

124. NB!

125. !
get
'/hello/:name'
=>
sub
($name)
{
!
vs.
!
get
'/hello/:name'
=>
sub($name)
{

126. ===SORRY!===
Error
while
compiling
test1.pl
Variable
'$name'
is
not
declared
at
test1.pl:7
!
-­‐-­‐-­‐-­‐-­‐-­‐>
get
'/hello/:name'
=>
sub(⏏$name)

127. Accessing request data

128. get
'/'
=>
sub
{
return
request.perl;
}

129. Bailador::Request.new(env
=>
{:HTTP_ACCEPT("*/
*"),
:HTTP_HOST("0.0.0.0:3000"),
:HTTP
_USER_AGENT("curl/
7.35.0"),
:PATH_INFO("/"),
:QUERY_STRI
NG(""),
:REQUEST_METHOD("GET"),
:REQUE
ST_URI("/"),
:SERVER_NAME("0.0.0.0"),
:SERVER_PORT(3000),
:SERVER_PROTOCOL("
HTTP/1.1"),
"p6sgi.encoding"
=>
"UTF-­‐8",
"p6sgi.errors"
=>
IO::Handle.new(path
=>
IO::Special.new(what
=>
"<STDERR>"),
ins
=>
0,
chomp
=>
Bool::True),

130. What is a ‘request’?

131. class
Bailador::App
{
.
.
.
method
request
{
$.context.request
}
method
response
{
$.context.response
}
.
.
.
}

132. get
/.*/
=>
sub
{
return
request.env<REQUEST_URI>
~
"n";
}

133. get
/.*/
=>
sub
{
return
request.env<REQUEST_URI>
~
"n";
}

134. Templates

135. get
'/'
=>
sub
{
template
't.tt',
{
name
=>
'Name'
}
}

136. get
'/'
=>
sub
{
template
't.tt',
{
name
=>
'Name'
}
}

137. %
my
($h)
=
@_;
<html>
<head>
<title>
Hi,
<%=
$h<name>
%>
</title>
</head>
<body>
<h1>Hello
<%=
$h<name>
%></h1>
</body>
</html>

138. %
my
($h)
=
@_;
<html>
<head>
<title>
Hi,
<%=
$h<name>
%>
</title>
</head>
<body>
<h1>Hello
<%=
$h<name>
%></h1>
</body>
</html>

139. Use
of
uninitialized
value
$_location
of
type
Any
in
string
context
Any
of
.^name,
.perl,
.gist,
or
.say
can
stringify
undefined
things,
if
needed.
in
method
template
at
/home/ash/p/rakudo-­‐
star-­‐2015.09/install/share/perl6/
site/lib/Bailador/App.pm:14
Failed
to
open
file
/views/t.tt:
no
such
file
or
directory
in
method
template
at

140. my
$_location;
!
.
.
.
!
$!renderer.render(
slurp(
"$_location/views/$tmpl"
),
@params
);
lib/Bailador/App.pm

141. my
$_location;
!
.
.
.
!
$!renderer.render(
slurp(
"$_location/views/$tmpl"
),
@params
);
lib/Bailador/App.pm

142. my
$_location
=
'.';
!
.
.
.
!
$!renderer.render(
slurp(
"$_location/views/$tmpl"
),
@params
);
lib/Bailador/App.pm

143. OK, Perl.
What about
databases?

144. DBIish

145. panda
install
DBIish

146. use
DBIish;

147. use
DBIish;
my
$dbh
=
DBIish.connect(
'mysql',
:host<example.com>,
:port(3306),
:database<$dbname>,
:user<$dbuser>,
:password<$dbpassword>);

148. my
$sth
=
$dbh.prepare(
"select
now()"
);
!
$sth.execute();

149. my
$arr
=
$sth.fetchall_arrayref();

150. my
$arr
=
$sth.fetchall_arrayref();
!
for
$arr
-­‐>
$x
{
say
$x;
}

151. It works!

152. __END__
Cluj-Napoka 2015
!
!
Andrew Shitov | andy@shitov.ru