implementado o tratamento para requisi??es http condicionais (cache)

Augusto Herrmann
1 parent 80a8857b
Showing 1 changed file with 12 additions and 3 deletions Show diff stats
app/barrabrasil.py
-from flask import Flask, url_for, render_template, request, make_response
+from flask import Flask, url_for, render_template, request, Response, make_response
+import hashlib
 app = Flask(__name__)
  
 @app.route('/')
@@ -25,8 +26,16 @@ def barra():
         'verde': '#00500F',
     }
     cor = paleta.get(nome_cor, '#004B82')
-    resposta = make_response(render_template('barra-brasil.js', cor=cor))
-    resposta.headers['Content-type'] = 'application/javascript'
+    conteudo = render_template('barra-brasil.js', cor=cor)
+    etag = hashlib.sha1(conteudo.encode('utf-8')).hexdigest()
+    if request.if_none_match and \
+              etag in request.if_none_match:
+        resposta = Response(status=304)
+    else: # nao esta em cache do navegador
+        resposta = make_response(conteudo)
+        resposta.set_etag(etag)
+        resposta.headers['Content-type'] = 'application/javascript'
+    resposta.headers['Cache-control'] = 'max-age: 3600'
     return resposta
  
 if __name__ == '__main__':
1		-from flask import Flask, url_for, render_template, request, make_response
	1	+from flask import Flask, url_for, render_template, request, Response, make_response
	2	+import hashlib
2	3	app = Flask(__name__)
3	4
4	5	@app.route('/')
...	...	@@ -25,8 +26,16 @@ def barra():
25	26	'verde': '#00500F',
26	27	}
27	28	cor = paleta.get(nome_cor, '#004B82')
28		- resposta = make_response(render_template('barra-brasil.js', cor=cor))
29		- resposta.headers['Content-type'] = 'application/javascript'
	29	+ conteudo = render_template('barra-brasil.js', cor=cor)
	30	+ etag = hashlib.sha1(conteudo.encode('utf-8')).hexdigest()
	31	+ if request.if_none_match and \
	32	+ etag in request.if_none_match:
	33	+ resposta = Response(status=304)
	34	+ else: # nao esta em cache do navegador
	35	+ resposta = make_response(conteudo)
	36	+ resposta.set_etag(etag)
	37	+ resposta.headers['Content-type'] = 'application/javascript'
	38	+ resposta.headers['Cache-control'] = 'max-age: 3600'
30	39	return resposta
31	40
32	41	if __name__ == '__main__':
...	...