jamesesilvia / cs542 Goto Github PK

On the client side, you enter a string instead of a number when prompted for a key. This works for all command types. Server accepts this and interprets string as the number 0, unless the string begins with a series of numbers, in which case that is the index used.

Steps to reproduce, with a few different scenarios:

1. Spawn server

2. Spawn client

3. On client, use put command

4. When prompted for key, type "test"

5. Continue entering parameters as normal

6. Note that data is put at index 0 (if empty)

7. On client, use get command

8. When prompted for key, type "foo"

9. Note that you actually get index 0

10. On client, use remove command

11. When prompted for key, type "bar"

12. Note that you actually remove index 0

13. On client, use put command

14. When prompted for key, type "22fast2furious"

15. Continue entering parameters as normal

16. Note that data is put at index 22 (if empty)

17. On client, use put command

18. When prompted for key, type "9 9999999"

19. When prompted for file, type "n"

20. When prompted for data, type "test"

21. Note that "9999999 test" is put at index 9 (if empty)

Looks like we just need to do some validation on the client side.

If multiple client actions are performed in quick succession then sometimes one client will get the results back from another client and vice versa. For example:

A performs REMOVE
B performs GET
A gets failed GET
B gets successful REMOVE

For example, if you have no cities with a population of 50000 in the DB, then a "Get_Index_By_Population 50000" is going to return READ FAILED instead of something like "No records found."

Very long strings are not stored in full, only the beginning is stored.

Steps to reproduce:

1. Spawn server
2. Spawn client
3. Find an empty index and use the put command on it
4. When it asks you to enter the data, hold down the a key for a really long time
5. Like, a really long time. A couple minutes. Put something on your keyboard and walk away.
6. When you come back, press enter to store the data
7. Use a get command on that index
8. Note that the full string does not get retrieved

This may have something to do with a maximum buffer length specified by the client/server communication

If two clients are active, quitting with one of them causes problems when another client tries to access the server.

Steps to reproduce:

1. Spawn server
2. Spawn client A
3. Spawn client B
4. Do a few actions on each client, but make sure you remove at index 8
5. On client A, quit
6. On client B, put the string "hi" at index 8
7. Server console should read:

The client disconnected!
Received: put 8 hi
Unable to send the data!
-bash-3.2$

8. Note that server is now disconnected
9. Note that the put command actually worked, and you can do a get on index 8 for "hi"

We may not be handling a disconnect properly in the event that many clients are connected to the server.

If a server receives two commands at about the same time, the commands are correctly processed. However, the server responds to the clients with the wrong message. Instead of the first client getting the message that corresponds with its command, it gets the message that corresponds with the second client's command.

Steps to reproduce:

1. Spawn server
2. Spawn client A
3. Spawn client B
4. Have client A put "test" in index 1 (if it fails, no big deal, that means there is something there already)
5. On client A, type "remove" and press enter
6. On client A, type "1" and stop
7. On client B, type "get" and press enter
8. On client B, type "1" and stop
9. Go back to client A, press enter, press Alt+Tab, and press enter (this will end up sending client B's command to the server also)
10. Note that the server received the commands properly and the get command fails, however the clients receive each other's messages from the server instead of their own

James said that tracking the clients would solve this issue and he knows how to fix it.

-> get
Please enter key to retrieve data: 3
Getting key: 3 with data...testtestøÔ

update to use MAX_STRING_LENGTH+1 in memory manager to protect against overflow.