newbee: Simple Backend Python Script Question

[joe shoemaker]

I need to create python script that is threaded. So the main program will
run in infinite loop and just retrieving messages and putting them in a
queue. (Main thread)

I need child threads from a pool to process the queue. When there is no
stuff in the queue, they go to the pool and become available but they don't
terminate. This has to be done continuously.

Main program need to keep putting stuff in the queue, when there are no
messages, then it sleeps for short time and check back to see any messages.

To do this, I guess you don't write joinAll(), so that the main threads just
don't wait for the child but goes to work.

am I right?

Also, child threads (a function that is threaded) will make connecitons to
the database. I am planning to use threadpool, so that threads reuse the
connections. So do you close the database connection at the end of the
function? If not then the connection will be opened forever?


Joe
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MD5 hash for url and utf unicode converting to ascii

[joe shoemaker]

I would like to convert url into md5 hash. My question is that md5
hash will create collision at 2^64. If you do long(value,16), where
value is the md5 hash string, would value returned from long(value,
16) be unique as long as md5 hashed string is unique? when you move
md5 hashed string to long, where will the collision occur, at anything
>= 2^64?

  hash = md5.new()
  hash.update("some_url_")
  value = hash.digest()
  value_in_int = long(value, 16) #would this be unique as long as
hashed string is unique(i.e < 2^64)
  hash = md5.new() hash.update("some_url_") value = hash.digest()
value_in_int = long(value, 16) #would this be unique as long as hashed
string is unique(i.e < 2^64)

Do I need to also convert the value to base64.encodestring(value)?
What is the purpose of base64.encodestring?

For unicode encoding, I can do, md5.update(value.encode('utf-8')) to
give me ascii values.


Thank you,
j
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Python pack and unpack question

[joe shoemaker]

If you have the following:

  data = unpack('>L', sock.recv(4))

Does this line of code means that incoming data is big endian and
unpack it to endianess of local machine? If local machine is little
endian, then big endian is automatically converted to little endian
format?

thank you.
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