Golang 101 for PHP Developers

A quick overview of the important parts, specifically focused on helping PHP developers.

Transcript

1. Golang 101
2. the basics
3. take the TOUR
4. Go is a compiled, statically typed language
5. our first PROGRAM
6. main.go p a c k a g e m a i n i m p o r t ( " f m t " ) f u n c m a i n ( ) { f m t . P r i n t f ( " H e l l o % s \ n " , " W o r l d " ) } $ g o r u n m a i n . g o H e l l o W o r l d $
7. SERVING the api
8. Golang operates similar to node in how it serves http
9. p a c k a g e m a i n i m p o r t " n e t / h t t p " f u n c s a y h e l l o N a m e ( w h t t p . R e s p o n s e W r i t e r , r * h t t p . R e q u e s t ) { f m t . F p r i n t f ( w , " H e l l o D a n i e l ! " ) / / s e n d d a t a t o c l i e n t s i d e } f u n c m a i n ( ) { h t t p . H a n d l e F u n c ( " / " , s a y h e l l o N a m e ) / / s e t r o u t e r e r r : = h t t p . L i s t e n A n d S e r v e ( " : 9 0 0 0 " , n i l ) / / s e t l i s t e n p o r t i f e r r ! = n i l { l o g . F a t a l ( " L i s t e n A n d S e r v e : " , e r r ) } } $ g o r u n m a i n . g o L i s t e n i n g : 9 0 0 0
10. that was easy (right?)
11. a quick primer on POINTERS
12. pointers Pointers are a reference (or pointer) to the actual value. They do not contain the value themselves. / / i n i t i a l i z e b o o k : = & B o o k { } / / s p e c i f y f u n c C h a n g e T i t l e ( b * B o o k ) { / / M o d i f y i n g ` b ` h e r e w i l l m u t a t e i t s v a l u e b . T i t l e = " N e w T i t l e " } C h a n g e T i t l e ( b o o k ) f m t . P r i n t l n ( b o o k . T i t l e ) / / P r i n t s " N e w T i t l e "
13. pointers values b o o k : = B o o k { } f u n c C h a n g e T i t l e ( b B o o k ) B o o k { / / M o d i f y i n g ` b ` w i l l n o t e x t e n d p a s t t h i s f u n c t i o n r e t u r n b } / / P o i n t e r / v a l u e c o n v e r s i o n b o o k P o i n t e r : = & B o o k { } b o o k V a l u e : = * b o o k P o i n t e r C h a n g e T i t l e ( b o o k V a l u e ) b o o k P o i n t e r A g a i n : = & b o o k V a l u e vs
14. why pointers Pointers save memory when passing data around the application. When passing values, the data is duplicated. Values are not allowed to be nil, but pointers are. Go will type-check against types and pointer/value.
15. from PHP to GO
16. there are no OBJECTS (but there are structs)
17. functions can return MULTIPLE VALUES (and it's seriously awesome)
18. typing is STRICT (obviously)
19. capital letters MATTER (exports must be capital)
20. now for some CODE
21. MAPS arrays
22. arrays In PHP, an array can actually be a map or an array $ a r r = [ ] ; In Go, you need to be explicit a r r : = [ ] s t r i n g { } a r r : = m a p [ s t r i n g ] i n t e r f a c e { } { }
23. arrays (well, actually maps) i f ( i s s e t ( $ _ P O S T [ ' i d ' ] ) ) { $ i d = $ _ P O S T [ ' i d ' ] ; / / D o s o m e t h i n g } vs i f i d , o k : = p o s t [ " i d " ] ; o k { / / D o s o m e t h i n g }
24. objects STRUCTS vs
25. objects c l a s s B o o k { p u b l i c $ t i t l e ; p u b l i c f u n c t i o n g e t A u t h o r ( ) { } } t y p e B o o k s t r u c t { T i t l e s t r i n g } f u n c ( b * B o o k ) G e t A u t h o r ( ) s t r i n g { }
26. objects $ b o o k = n e w B o o k ( [ ' t i t l e ' = > ' W h e n I W o r k , T h e B o o k ' , ] ) ; $ a u t h o r = $ b o o k ­ > g e t A u t h o r ( ) ; b o o k : = & B o o k { T i t l e : " W h e n I W o r k , T h e B o o k " , } a u t h o r : = b o o k . G e t A u t h o r ( )
27. extend objects c l a s s H a r d c o v e r e x t e n d s B o o k { p u b l i c f u n c t i o n i s H a r d c o v e r ( ) { r e t u r n t r u e ; } } t y p e H a r d c o v e r s t r u c t { * B o o k } f u n c ( b * H a r d c o v e r ) G e t T i t l e ( ) s t r i n g { r e t u r n f m t . S p r i n t f ( " % s [ H a r d c o v e r ] " , b . T i t l e ) / / O r r e t u r n f m t . S p r i n t f ( " % s [ H a r d c o v e r ] " , b . B o o k . T i t l e ) }
28. methods and FUNCTIONS
29. our struct t y p e A u t h o r s t r u c t { N a m e s t r u c t { F i r s t s t r i n g L a s t s t r i n g } B o o k s [ ] B o o k }
30. method function / / F u n c t i o n f u n c A d d B o o k ( a * A u t h o r , b B o o k ) { a . B o o k s = a p p e n d ( a . B o o k s , b ) } A d d B o o k ( a u t h o r , b o o k ) / / M e t h o d f u n c ( a * A u t h o r ) A d d B o o k ( b B o o k ) { a . B o o k s = a p p e n d ( a . B o o k s , b ) } a u t h o r . A d d B o o k ( b o o k ) vs
31. more on methods / / C a n m o d i f y A u t h o r f u n c ( a * A u t h o r ) A d d B o o k ( b B o o k ) { a . B o o k s = a p p e n d ( a . B o o k s , b ) } / / C a n n o t m o d i f y A u t h o r f u n c ( a A u t h o r ) F u l l N a m e ( ) s t r i n g { r e t u r n a . N a m e . F i r s t + " " + a . N a m e . L a s t } But they can both be called in the same way from the struct
32. OH MY interfaces
33. interfaces i n t e r f a c e B o u n d { p u b l i c f u n c t i o n p a g e C o u n t ( ) ; } t y p e B o u n d i n t e r f a c e { P a g e C o u n t ( ) i n t }
34. interfaces c l a s s B o o k i m p l e m e n t s B o u n d { p u b l i c f u n c t i o n p a g e C o u n t ( ) { r e t u r n c o u n t ( $ t h i s ­ > p a g e s ) ; } } t y p e B o o k s t r u c t { p a g e s [ ] P a g e } f u n c ( b * B o o k ) P a g e C o u n t ( ) i n t { r e t u r n l e n ( b . p a g e s ) }
35. TYPE casting
36. type casting conversion $ a u t h o r _ i d = ( i n t ) $ i d ; In Go, types are strict, but can still be converted i : = 4 2 f : = f l o a t 6 4 ( i ) u : = u i n t ( f )
37. type assertion Go also has the concept of checking an internal type f u n c S e t A u t h o r ( o b j i n t e r f a c e { } ) { i f a u t h o r , o k : = o b j . ( s t r i n g ) ; o k { / / o b j c o n t a i n s s t r i n g / / a u t h o r i s n o w a s t r i n g } }
38. type assertion In Go you can also check an object against an interface t y p e B o u n d i n t e r f a c e { P a g e C o u n t ( ) i n t } i f b o o k , o k : = b o u n d . ( B o o k ) ; o k { f m t . P r i n t l n ( b o o k . T i t l e ) }
39. where to go from FROM HERE take the tour write an app concurrency experiment have fun
40. FIN (but more to come ... soon™)
41. @dolfelt github, twitter, etc