Initial commit

2020-01-19 14:10:12 +01:00
commit 970e65d414
2 changed files with 81 additions and 0 deletions
--- a/43
+++ b/43
@@ -0,0 +1,43 @@
+#!/usr/bin/python3
+
+from flask import Flask, escape, request
+from time import sleep, time, ctime
+from flaskcache import FlaskCache
+
+app = Flask(__name__)
+fc  = FlaskCache()
+
+def page(name, count, delta=0.2):
+    page= (
+             "<!DOCTYPE html>\n"
+             "<html xmlns=\"http://www.w3.org/1999/xhtml\">\n"
+             "<head>\n"
+             "  <meta name=\"generator\" content=\"flask\">\n"
+             "  <title>%s<title/>\n"
+             "</head>\n"
+             "<body>\n"
+             "<h1>%s<s/h1>\n"
+             "<h2>time</h2>\n"
+             "  %f<br />\n"
+             "  %s<br />\n"
+             "<h2>data</h2>\n"
+          ) % (name, name, time(), ctime())
+    for i in range(1, count+1):
+        page += "  %i<br />\n" % i
+        sleep(delta)
+    page += (
+               "</body>\n"
+               "</html>\n"
+            )
+    return(page)
+
+@app.route('/p1')
+def p1():
+    return(fc.getpage("/p1", page, "p1", 5))
+
+@app.route('/p2')
+def p2():
+    return(fc.getpage("/p2", page, "p2", 10, 0.5))
+
+if __name__ == '__main__':
+    app.run()
--- a/flaskcache.py
+++ b/flaskcache.py
@@ -0,0 +1,38 @@
+from time import time
+from threading import Lock
+
+class FlaskCache:
+    def __init__(self, timeout=20):
+        self.timeout = timeout
+        self.cache   = {}
+        self.lock    = {}
+
+    def genpage(self, pagefunc, *args):
+        page = {}
+        try:
+            page["page"]   = pagefunc(*args)
+            page["code"] = 200
+        except Exception as e:
+            page["page"]   = "ERROR\n"
+            page["code"] = 500
+        page["time"] = time()
+        return(page)
+
+    def cachetime(self, pagename):
+        try:
+            delta = self.cache[pagename]["time"] + self.timeout - time()
+        except Exception as e:
+            delta = -1
+        return(delta)
+
+    def getpage(self, pagename, pagefunc, *args):
+        if pagename not in self.cache:
+            self.cache[pagename] = {}
+        if pagename not in self.lock:
+            self.lock[pagename] = Lock()
+        if (self.cachetime(pagename) <= 0):
+            self.lock[pagename].acquire()
+            if (self.cachetime(pagename) <= 0):
+                self.cache[pagename] = self.genpage(pagefunc, *args)
+            self.lock[pagename].release()
+        return(self.cache[pagename]["page"], self.cache[pagename]["code"])