GIT-37: fix blueprint middleware application

[harshanarayana]

1. If you register a middleware via @blueprint.middleware then it will apply only to the routes defined by the blueprint.
2. If you register a middleware via @blueprint_group.middleware then it will apply to all blueprint based routes that are part of the group.
3. If you define a middleware via @app.middleware then it will be applied on all available routes

Fixes #37

[codecov]

Codecov Report

Merging #1690 into master will decrease coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #1690      +/-   ##
==========================================
- Coverage   92.09%   92.09%   -0.01%     
==========================================
  Files          22       22              
  Lines        2215     2238      +23     
  Branches      411      419       +8     
==========================================
+ Hits         2040     2061      +21     
  Misses        137      137              
- Partials       38       40       +2

Impacted Files	Coverage Δ
sanic/app.py	92.17% <100%> (-0.1%)	⬇️
sanic/router.py	95.49% <100%> (+0.06%)	⬆️

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[harshanarayana]

@huge-success/sanic-core-devs Can you please take a look at this PR and see if this looks good? We can close a pretty old issue with this one.

[sjsadowski]

@harshanarayana do we need to add test to prevent reversions for this behavior?

[harshanarayana]

@sjsadowski

do we need to add tests to prevent reversions for this behavior?

Existing tests have been modified to assert new behavior. So any change in this behavior again will cause those tests to fail. Do you happen to have any specific scenario in mind that I may have missed ?

[harshanarayana]

@huge-success/sanic-core-devs Can we get this one into the next release ? This is sort of a breaking change but in the right direction

[harshanarayana]

cc @huge-success/sanic-core-devs

[sjsadowski]

I've approved it. I'm going to add a note on sanicframework.org and figure out how to call it out in the generated release notes before merging.

[harshanarayana]

figure out how to call it out in the generated release notes before merging.

@sjsadowski This can be done easily. I've added a command make release that will generate the changelog based on the added changelogs snippet.

[sjsadowski]

@harshanarayana awesome!