PYTHON REFACTORING WITH ROPE AND TRAAD Austin Bingham Sixty North AS 0 

HELLO! 

PYTHON IS EVERYWHERE! 

WHAT IS ROPE? 

A PYTHON LIBRARY FOR DOING PYTHON REFACTORINGS 

ROPE HAS POWERFUL IDE- ORIENTED FEATURES Code completion Finding definitions and occurrences Organizing imports Looking up docstrings 

ELEMENTS OF ROPE 

PROJECT Represents the files and directories containing code that rope will manipulate. P r o j e c t is the root object in rope 

CREATE A PROJECT f r o m r o p e . b a s e . p r o j e c t i m p o r t P r o j e c t p r o j e c t = P r o j e c t ( ' p r o j e c t _ d i r ' ) 

WALK PROJECT RESOURCES d e f g e t _ a l l _ r e s o u r c e s ( p r o j ) : t o d o = [ ' ' ] w h i l e t o d o : r e s _ p a t h = t o d o [ 0 ] t o d o = t o d o [ 1 : ] r e s = p r o j . g e t _ r e s o u r c e ( r e s _ p a t h ) y i e l d ( r e s . p a t h , r e s . i s _ f o l d e r ( ) ) i f r e s . i s _ f o l d e r ( ) : t o d o . e x t e n d ( ( c h i l d . p a t h f o r c h i l d i n r e s . g e t _ c h i l d r e n ( ) ) ) P r o j e c t . g e t _ r e s o u r c e ( p a t h ) finds a resource at a relative path R e s o u r c e . g e t _ c h i l d r e n ( ) returns an iterable over children 

MANAGE PREFERENCES p r e f s is a dict-like container of settings and preferences. f o r p i n p r o j e c t . p r e f s . p r e f s : p r i n t ( p r o j e c t . p r e f s . g e t ( p ) ) p r e f s are stored in a file called . r o p e p r o j e c t / c o n f i g . p y at the project's root directory. 

RESOURCES The files and directories in the project s e r v e r = p r o j e c t . g e t _ r e s o u r c e ( ' t r a a d / s e r v e r . p y ' ) p r i n t ( s e r v e r . n a m e , s e r v e r . p a t h , s e r v e r . i s _ f o l d e r ( ) ) c 1 = p r o j e c t . g e t _ r e s o u r c e ( ' ' ) . g e t _ c h i l d r e n ( ) [ 0 ] p r i n t ( c 1 . n a m e , c 1 . p a t h , c 1 . i s _ f o l d e r ( ) ) 

ANATOMY OF A REFACTORING 

CREATE THE REFACTORING OBJECT f r o m r o p e . r e f a c t o r . r e n a m e i m p o r t R e n a m e r e n = R e n a m e ( p r o j e c t , p r o j e c t . g e t _ r e s o u r c e ( ' t r a a d / s t a t e . p y ' ) , o f f s e t = 4 2 ) This can fail if rope can't perform the refactoring The refactoring is only partially bound 

CALCULATE ACTUAL CHANGES c h a n g e s = r e n . g e t _ c h a n g e s ( ' T a c o C o p t e r ' ) p r i n t ( c h a n g e s . d e s c r i p t i o n ) p r i n t ( c h a n g e s . g e t _ c h a n g e d _ r e s o u r c e s ( ) ) c h a n g e s represents a fully bound change 

EXECUTE THE CHANGES p r o j e c t . d o ( c h a n g e s ) After this the changes are actually performed. 

THE FULL PROCESS f r o m r o p e . b a s e . p r o j e c t i m p o r t P r o j e c t f r o m r o p e . r e f a c t o r . r e n a m e i m p o r t R e n a m e # C r e a t e t h e p r o j e c t p r o j = P r o j e c t ( ' . ' ) # C r e a t e t h e p a r t i a l l y - b o u n d r e f a c t o r i n g r e n = R e n a m e ( p r o j e c t , p r o j e c t . g e t _ r e s o u r c e ( ' t r a a d / s t a t e . p y ' ) , o f f s e t = 4 2 ) # C a l c u l a t e t h e c h a n g e s f o r a f u l l y - s p e c i f i e d r e n a m i n g c h a n g e = r e n . g e t _ c h a n g e s ( ' T a c o C o p t e r ' ) # P e r f o r m t h e c h a n g e s p r o j e c t . d o . c h a n g e s ( ) 

HISTORY 

H I S T O R Y OBJECT P r o j e c t . h i s t o r y manages the history of changes that have been made. Also remembers what has been undone as well as change dependencies. 

UNDOING CHANGES Undo the most recent changes p r o j e c t . h i s t o r y . u n d o ( ) Or select more distance changes to undo c h a n g e = p r o j e c t . h i s t o r y . u n d o _ l i s t [ 3 ] p r o j e c t . h i s t o r y . u n d o ( c h a n g e ) This will undo all dependent changes. 

REDOING CHANGES You can redo changes that you've previously undone. c h a n g e = p r o j e c t . h i s t o r y . r e d o _ l i s t [ - 2 ] p r o j e c t . h i s t o r y . r e d o ( c h a n g e ) 

MULTI-PROJECT REFACTORING 

THE MULTI-PROJECT REFACTORING CLASS First create a M u l t i P r o j e c t R e f a c t o r i n g instance. f r o m r o p e . r e f a c t o r i m p o r t m u l t i p r o j e c t m p r = m u l t i p r o j e c t . M u l t i P r o j e c t R e f a c t o r i n g ( R e n a m e , # t y p e o f r e f a c t o r i n g t o p e r f o r m [ o t h e r _ p r o j e c t 1 , o t h e r _ p r o j e c t 2 , o t h e r _ p r o j e c t 3 ] ) Then call that with your main project and the refactoring initializer arguments r e f = m p r ( m a i n _ p r o j e c t , s o m e _ r e s o u r c e , o f f s e t = 1 3 3 7 ) 

CREATE AND PERFORM THE CHANGE # R e m e m b e r t h a t ` r e f ` i s a r e n a m i n g o p e r a t i o n c h a n g e s = r e f . g e t _ a l l _ c h a n g e s ( " E n t e r p r i s e P r o x y M a n a g e r I m p l e m e n t a t i o n F a c t o r y F a c t o r y " ) m u l t i p r o j e c t . p e r f o r m ( c h a n g e s ) 

NON-REFACTORING TOOLS 

NOT INTENDED FOR "MANUAL" OPERATION 

WHAT IS TRAAD? tråd - svært tynn snor av fibrer av silke, ull, el. f eks av metall 

WHAT IS TRAAD? thread 

TRAAD IS… An HTTP+JSON server for driving rope 

TRAAD IS… Various clients for driving the server 

WHY TRAAD? 

SIMPLER INTEGRATION WITH EDITORS Every corner of the programming universe knows how to speak HTTP+JSON 

HTTP IS (WAY) MORE THAN FAST ENOUGH FOR THIS WORK The volume of data is low, and the response time only needs to be good enough for humans 

SUPPORT FOR MULTIPLE PYTHON VERSIONS The client has zero depenencies on the version of Python that traad is using 

PROPER LEVEL OF ABSTRACTION The problem domain of traad is Python refactoring, not Python integration with other languages. 

TRAAD ARCHITECTURE 

Low-ceremony (sorta), powerful, and well-documented 

PYKKA FOR MANAGING CONCURRENCY 

OVERALL ARCHITECTURE 

TASK STATE { 1 : { ' s t a t u s ' : ' p e n d i n g ' , ' d e s c r i p t i o n ' : ' R e n a m i n g F O O t o B A R ' , ' c h a n g e d _ r e s o u r c e s ' : [ . . . ] } , 2 : { ' s t a t u s ' : ' f a i l u r e ' } , 3 : { ' s t a t u s ' : ' s u c c e s s ' , ' c a l l t i p ' : ' u u i d 1 ( n o d e = N o n e , c l o c k _ s e q = N o n e ) ' } } Simple mapping of task-ids to dicts State is an actor and thus threadsafe. Multiple asynchronous tasks could be accessing it at any time. 

ASYNCHRONOUS OPERATIONS 

SYNCHRONOUS OPERATIONS 

ASYCHRONOUS VS. SYNCHRONOUS Asynchronous Rename Extract Organize imports Synchronous Find definition Get history Calltip 

EMACS The emacs lisp for renaming looks like this ; S t a r t s n e w t r a a d s e r v e r o n t h e s p e c i f i e d d i r e c t o r y ( t r a a d - o p e n " ~ / p r o j e c t s / r o i d _ r a g e " ) ; R e n a m e s w h a t e v e r i s a t h e p o i n t ( i . e . u n d e r t h e c u r s o r ) ( t r a a d - r e n a m e " R a g i n g R o i d " ) And the HTTP message looks like this P O S T / r e f a c t o r / r e n a m e H T T P / 1 . 1 U s e r - A g e n t : c u r l / 7 . 3 0 . 0 H o s t : 1 2 7 . 0 . 0 . 1 : 6 5 1 7 2 A c c e p t : * / * A c c e p t - E n c o d i n g : d e f l a t e , g z i p C o n t e n t - T y p e : a p p l i c a t i o n / j s o n C o n t e n t - L e n g t h : 1 0 4 { " n a m e " : " R a g i n g R o i d " , " p a t h " : " \ / U s e r s \ / s i x t y n o r t h \ / p r o j e c t s \ / r o i d _ r a g e \ / r o i d _ r a g e \ / r o i d . p y " , " o f f s e t " : 1 0 2 } 

DEMOS 

SIMPLE RENAMING 

IMPORT CLEANUP 

HISTORY 

LINKS Rope - Traad - Pykka - Bottle - http://rope.sourceforge.net/ http://github.com/abingham/traad http://www.pykka.org/ http://bottlepy.org/ http://github.com/abingham/traad_rope_presentation 

No content