Mon 02 November 2015
tags: development git
When reviewing a pull request against nameko today there was a chunk of code moved from a function into a method, though oterwise mostly unchanged. Unfortunately, it also moved around in the file, and so even git diff -w (abbreviation for git diff --ignore-all-space), ignoring all whitespace showed everything as changed.
Fortunetely, I remembered a trick I found a while ago using git blame
| egrep '^[^\^]'
That's blame, -s (suppress author and timestamp in output) -w (ignore whitespace) -C (detect lines moved from other files)
This will show the file, with each line prefixed with information about which commit it came from. However, because we are limiting our diff to the range master..HEAD (from master to the head of the pull request), lines originally written (up to whitespace changes) earlier than master, get marked with ^<sha>, where <sha> is the commit-sha for master. We use egrep to find lines starting with ^.
This can be slightly tricky to read, but there's one more trick:
| egrep --color= always '^[^\^]|^' | less -R
Here we match either entire lines beginning with ^, or just the beginning of all other lines. That way we can ask egrep to hightligh the matches, and it will highlight just those lines starting with a caret, but output all lines ("highlighting" just the empty start-of-line mark). Finally we pipe to less for pagination, making sure to use -R to re-parse the terminal color codes from egrep.
Original diff
diff --git a/nameko/web/handlers.py b/nameko/web/handlers.py
index a4f6b1a..d9a2c9f 100644
--- a/nameko/web/handlers.py
+++ b/nameko/web/handlers.py
@@ -14,30 +14,6 @@ from nameko.web.server import WebServer
_log = getLogger(__name__)
-def response_from_result(result):
- if isinstance(result, Response):
- return result
-
- headers = None
- if isinstance(result, tuple):
- if len(result) == 3:
- status, headers, payload = result
- else:
- status, payload = result
- else:
- payload = result
- status = 200
-
- if not isinstance(payload, six.string_types):
- raise TypeError("Payload must be a string. Got `{!r}`".format(payload))
-
- return Response(
- payload,
- status=status,
- headers=headers,
- )
-
-
class HttpRequestHandler(Entrypoint):
server = WebServer()
@@ -74,9 +50,42 @@ class HttpRequestHandler(Entrypoint):
handle_result=partial(self.handle_result, event))
result = event.wait()
- response = response_from_result(result)
+ response = self.response_from_result(result)
except Exception as exc:
+ response = self.response_from_exception(exc)
+ return response
+
+ def handle_result(self, event, worker_ctx, result, exc_info):
+ event.send(result, exc_info)
+ return result, exc_info
+
+ def response_from_result(self, result):
+ if isinstance(result, Response):
+ return result
+
+ headers = None
+ if isinstance(result, tuple):
+ if len(result) == 3:
+ status, headers, payload = result
+ else:
+ status, payload = result
+ else:
+ payload = result
+ status = 200
+
+ if not isinstance(payload, six.string_types):
+ raise TypeError(
+ "Payload must be a string. Got `{!r}`".format(payload)
+ )
+
+ return Response(
+ payload,
+ status=status,
+ headers=headers,
+ )
+
+ def response_from_exception(self, exc):
if (
isinstance(exc, self.expected_exceptions) or
isinstance(exc, BadRequest)
@@ -87,15 +96,9 @@ class HttpRequestHandler(Entrypoint):
error_dict = serialize(exc)
payload = u'Error: {exc_type}: {value}\n'.format(**error_dict)
- response = Response(
+ return Response(
payload,
status=status_code,
)
- return response
-
- def handle_result(self, event, worker_ctx, result, exc_info):
- event.send(result, exc_info)
- return result, exc_info
-
http = HttpRequestHandler.decorator
Blame + egrep
Blame-diff
^ f5d1f2c 1 ) from logging import getLogger
^ f5d1f2c 2 ) from functools import partial
^ f5d1f2c 3 )
^ f5d1f2c 4 ) from eventlet.event import Event
^ f5d1f2c 5 ) import six
^ f5d1f2c 6 ) from werkzeug.wrappers import Response
^ f5d1f2c 7 ) from werkzeug.routing import Rule
^ f5d1f2c 8 )
^ f5d1f2c 9 ) from nameko.exceptions import serialize , BadRequest
^ f5d1f2c 10 ) from nameko.extensions import Entrypoint
^ f5d1f2c 11 ) from nameko.web.server import WebServer
^ f5d1f2c 12 )
^ f5d1f2c 13 )
^ f5d1f2c 14 ) _log = getLogger ( __name__ )
^ f5d1f2c 15 )
^ f5d1f2c 16 )
^ f5d1f2c 17 ) class HttpRequestHandler ( Entrypoint ):
^ f5d1f2c 18 ) server = WebServer ()
^ f5d1f2c 19 )
^ f5d1f2c 20 ) def __init__ ( self , method , url , expected_exceptions = ()):
^ f5d1f2c 21 ) self . method = method
^ f5d1f2c 22 ) self . url = url
^ f5d1f2c 23 ) self . expected_exceptions = expected_exceptions
^ f5d1f2c 24 )
^ f5d1f2c 25 ) def get_url_rule ( self ):
^ f5d1f2c 26 ) return Rule ( self . url , methods = [ self . method ])
^ f5d1f2c 27 )
^ f5d1f2c 28 ) def setup ( self ):
^ f5d1f2c 29 ) self . server . register_provider ( self )
^ f5d1f2c 30 )
^ f5d1f2c 31 ) def stop ( self ):
^ f5d1f2c 32 ) self . server . unregister_provider ( self )
^ f5d1f2c 33 ) super ( HttpRequestHandler , self ) . stop ()
^ f5d1f2c 34 )
^ f5d1f2c 35 ) def get_entrypoint_parameters ( self , request ):
^ f5d1f2c 36 ) args = ( request ,)
^ f5d1f2c 37 ) kwargs = request . path_values
^ f5d1f2c 38 ) return args , kwargs
^ f5d1f2c 39 )
^ f5d1f2c 40 ) def handle_request ( self , request ):
^ f5d1f2c 41 ) request . shallow = False
^ f5d1f2c 42 ) try :
^ f5d1f2c 43 ) context_data = self . server . context_data_from_headers ( request )
^ f5d1f2c 44 ) args , kwargs = self . get_entrypoint_parameters ( request )
^ f5d1f2c 45 )
^ f5d1f2c 46 ) self . check_signature ( args , kwargs )
^ f5d1f2c 47 ) event = Event ()
^ f5d1f2c 48 ) self . container . spawn_worker (
^ f5d1f2c 49 ) self , args , kwargs , context_data = context_data ,
^ f5d1f2c 50 ) handle_result = partial ( self . handle_result , event ))
^ f5d1f2c 51 ) result = event . wait ()
^ f5d1f2c 52 )
273 ee975 53 ) response = self . response_from_result ( result )
^ f5d1f2c 54 )
^ f5d1f2c 55 ) except Exception as exc :
273 ee975 56 ) response = self . response_from_exception ( exc )
^ f5d1f2c 57 ) return response
^ f5d1f2c 58 )
^ f5d1f2c 59 ) def handle_result ( self , event , worker_ctx , result , exc_info ):
^ f5d1f2c 60 ) event . send ( result , exc_info )
^ f5d1f2c 61 ) return result , exc_info
^ f5d1f2c 62 )
273 ee975 63 ) def response_from_result ( self , result ):
^ f5d1f2c 64 ) if isinstance ( result , Response ):
^ f5d1f2c 65 ) return result
^ f5d1f2c 66 )
^ f5d1f2c 67 ) headers = None
^ f5d1f2c 68 ) if isinstance ( result , tuple ):
^ f5d1f2c 69 ) if len ( result ) == 3 :
^ f5d1f2c 70 ) status , headers , payload = result
^ f5d1f2c 71 ) else :
^ f5d1f2c 72 ) status , payload = result
^ f5d1f2c 73 ) else :
^ f5d1f2c 74 ) payload = result
^ f5d1f2c 75 ) status = 200
^ f5d1f2c 76 )
^ f5d1f2c 77 ) if not isinstance ( payload , six . string_types ):
273 ee975 78 ) raise TypeError (
273 ee975 79 ) "Payload must be a string. Got `{!r}`" . format ( payload )
273 ee975 80 ) )
^ f5d1f2c 81 )
^ f5d1f2c 82 ) return Response (
^ f5d1f2c 83 ) payload ,
^ f5d1f2c 84 ) status = status ,
^ f5d1f2c 85 ) headers = headers ,
^ f5d1f2c 86 ) )
^ f5d1f2c 87 )
273 ee975 88 ) def response_from_exception ( self , exc ):
^ f5d1f2c 89 ) if (
^ f5d1f2c 90 ) isinstance ( exc , self . expected_exceptions ) or
^ f5d1f2c 91 ) isinstance ( exc , BadRequest )
^ f5d1f2c 92 ) ):
^ f5d1f2c 93 ) status_code = 400
^ f5d1f2c 94 ) else :
^ f5d1f2c 95 ) status_code = 500
^ f5d1f2c 96 ) error_dict = serialize ( exc )
^ f5d1f2c 97 ) payload = u 'Error: {exc_type}: {value} \n ' . format ( ** error_dict )
^ f5d1f2c 98 )
273 ee975 99 ) return Response (
^ f5d1f2c 100 ) payload ,
^ f5d1f2c 101 ) status = status_code ,
^ f5d1f2c 102 ) )
^ f5d1f2c 103 )
^ f5d1f2c 104 ) http = HttpRequestHandler . decorator