Networking
Multi-Threading
Concurrency Issues
API Querying
Introduction
After a stressful and sweaty pitch, the Council of SAL is satisfied with your trade-
scheduling prototype demo application and has unanimously decided to give you the
green light to fully implement your application. This involves pulling real data from
Tiingo, issuing trades from SalStocks trading platform to traders in real time over the
network, and chaining trades for traders, much like some other stock trade
application whose name shall not be mentioned. A successful implementation will
gain you 5 points and possibly a good word from the director.
Tiingo API
In addition to reading in data from two hard-coded csv files, you will use the Tiingo
API to retrieve company stock costs. In other words, the company stock cost should
be pulled from this API, and you will only have to read from the csv files for the
schedule of trades and initial trader balances. You can learn more about the Tiingo
API here: https://api.tiingo.com/documentation/general/overview . The data will be
returned in a JSON format.
Please keep in mind that there are hourly, daily and monthly limits, so do not wait to
start your assignment until the last day. You will also need to generate an API Key,
so start the assignment early to allow enough time for testing.
Assignment
In this assignment, you will create two different programs – a server and a client. You
will implement a networked delivery system where clients (which represent traders)
receive trades from the server (which represents the trading platform), and the
traders will complete the trades of the appropriate company stocks.
There will be some concurrency issues since traders will have to wait on other
traders before starting the trade. There will be many ways to design out the program,
so it would be wise to spend some time designing the program before you begin
coding.
Similar to the previous assignment, here is a sample schedule.csv file:
0, AAPL, 2, 2021-02-19
0, AAPL, -1, 2021-02-19
0, AMD, 5, 2021-02-19
2, MSFT, -1, 2021-02-19 2, MSFT, -2, 2021-02-19 9, MSFT, -1, 2021-02-19
9, MSFT, 1, 2021-02-19 9, TSLA, 2, 2021-02-19
12, TSLA, 1, 2021-02-19
12, TSLA, -3, 2021-02-19
But there is an additional field specifying the date in the format YYYY-MM-DD. You
will use this date in the Historical Price Information endpoint shown below to get the
stock price details for that date like this:
https://api.tiingo.com/tiingo/daily/AMD/prices?startDate=2021- 02-19&endDate=2021-02- 19&token=6af808f3212a2076bf8aefb97835022531450323
Note: you will need to replace the token with your own.
You will get a response something like this:
[
{
"date":"2021-02-19T00:00:00.000Z",
"close":89.58,
"high":90.4163,
"low":88.69,
"open":89.75,
"volume":29548273,
"adjClose":89.58,
"adjHigh":90.4163,
"adjLow":88.69,
"adjOpen":89.75,
"adjVolume":29548273,
"divCash":0.0,
"splitFactor":1.0
} ]
The documentation for this Tiingo API is listed in section 2.1.2, End-Of-day Endpoint at:
https://api.tiingo.com/documentation/end-of-day
You will use the price corresponding to the “close” key above as the price for 1 stock
of the specific company. Here the price for 1 stock of AMD is $89.58.
Aside from the schedule.csv file, you will need to read in a second file called
traders.csv, in CSV format. Below is a layout of the second file, which contains
information about the traders:
1, 1000 2, 2000
2
On each line of the CSV file, you will have the following fields:
● The first field indicates the serial number of the trader.
● The second field indicates the initial starting balance of the trader.
Server Functionality
When your server first runs, prompt the user for the name of the schedule file. Then
it will prompt the user for the name of the traders file. The number of traders
dispatched will be equal to the number of records in the traders.csv file. For
example, if there are 2 records corresponding to 2 traders in the traders.csv file that
means the server will not send out any orders until 2 clients (aka traders) have
connected to the server. Afterwards, the server should begin listening on port 3456
for client connections. Every time a client connects to the server, verify that the
connection was made by printing an output from the server, similar to the sample
output below.
Client Functionality
The client will begin by welcoming the user to the program and prompt the user for the server hostname and port. If a valid connection is made, the program should let the user know how many more traders are needed before the trades are started. For example, in the case when there are 2 records in the traders.csv file, if there is currently only 1 connection, the client should print a message saying that 1 more trader is needed before the trades can be started.
the stock prices of each company’s stock.
Once the trades are initiated, the client will be responsible for completing the trade of
the appropriate company stocks. The client should also be handling the returned
data from the API calls to determine
Program Execution
Unlike the previous homework assignment, traders can take up and be responsible
for more than one trade at a time. Additionally, traders can take up and be
responsible for trades of multiple company stocks at a time.
A trader should take up as many trades as possible at the moment of initiation,
provided that the sum obtained on totalling the money required for executing the
purchase trades is less than or equal to the current balance of the trader. This
means that if there are 5 trades that all have the same timestamp and all are
purchase trades of value $100 each, a trader having a current remaining balance of
$400 would be able to pick up and be responsible for only 4 of those 5 trades. As
long as there are available traders, trades should be assigned promptly. If there are
no available traders, the trade request will remain in the queue until a trader
completes their trade. Once a trader completes, the trader should pick up as many of the queued trade requests (with respect to the current time) as are permissible under
that trader’s balance limit.
3
Points to keep in mind:
1. Theexecutionofapurchasetradeshouldresultinthereductionofthecurrent
balance of the trader who executed that trade, by an amount equal to the cost
of that purchase trade.
2. Theexecutionofasellingtradewillnotresultinanychangestothe
current balance of the trader. You could consider the initial balance of each
trader as a limit that they should not cross for total stock purchases.
3. Ifatapointintimetherearemultiplefreetraders,theassignmentoftrades
should be done in the ascending order of the serial numbers of the traders.
4. Theprogramshouldsleepfor1secondforeachtradethatisbeingexecuted.
5. Thetradesshouldbeassignedintheordertheyarepresentinthe
schedule.csv file.
6. Considerthesituationwherethefollowingtradesarenotexecutedbecause
none of the traders have enough balance:
a. 12, TSLA, 1, 2021-02-19
b. 12, MSFT, 10, 2021-02-19
At the end you need to print them as follows:
Incomplete trades: (12, TSLA, 1, 2021-02-19),(12, MSFT,
10, 2021-02-19)
If there are no incomplete trades, then print: Incomplete trades:NONE
7. Attheendalsoprintthetotalprofitearnedbyeachclient(trader)whichisthe
sum of all the sales that the trader did.
Please follow the sample execution below for the proper output format.
NOTE: It is not a requirement for the timestamps to start from all 0s, but you could
do it as a learning exercise. But no points will be deducted for this. The time stamp
format should be correct.
4
Sample Execution
Below is a sample execution of the program. The timestamp has been bolded to
make it easier to read for this sample output.
Server Client 1 Client 2
What is the path
of the schedule
file?
missing.csv
That file does
not exist. What
is the path of
the schedule
file?
schedule.csv
The schedule file has been properly
read.
What is the path
of the traders
file?
missing.csv
That file does
not exist. What
is the path of
the traders file?
traders.csv
The traders file
has been properly
read.
Listening on port
3456.
Waiting for
traders…
Connection from
Welcome to SalStocks
v2.0!
Enter the server
hostname: localhost
Enter the server
port: 3456
5
127.0.0.1
Waiting for 1
Connection from
127.0.0.1
1 more trader is
needed before the
more trader(s)...
service can begin.
Waiting…
Welcome to SalStocks
v2.0!
Enter the server
hostname: localhost
Enter the server
port: 3456
Starting service.
All traders have
arrived!
Starting service.
All traders have
arrived!
Starting service.
[00:00:000] Assigned purchase of 2 stocks
of APPL. Total cost
estimate= $129.87*2=
$259.74.
[00:00:000] Assigned
sale of 1 stock of
APPL. Total gain
estimate= $129.87*1=
$129.87.
[00:00:000] Assigned purchase of 5 stocks
of AMD. Total cost
estimate= $89.58*5=
$447.9.
[00:00:000] Starting purchase of 2 stocks of APPL. Total cost=
$129.87*2= $259.74.
[00:01.000] Finished purchase of 2 stocks
of APPL. Remaining
balance= $1000-
$259.74= $740.26.
[00:01.000] Starting
sale of 1 stock of
APPL. Total gain=
$129.87*1= $129.87.
[00:02.000] Finished
sale of 1 stock of
APPL. Profit earned
till now=
$0+$129.87= $129.87. [00:02.000] Starting
[00:02:000] Assigned
sale of 1 stock of
MSFT. Total gain=
$240.97*1= $240.97.
[00:02:000] Assigned
6
sale of 2 stocks of
MSFT. Total gain=
$240.97*2= $481.94. [00:02:000]Starting
sale of 1 stock of
MSFT. Total gain=
$240.97*1= $240.97. [00:03:000]Finished
sale of 1 stock of
MSFT. Profit earned
till now=
$0+$240.97= $240.97.
[00:03:000]Starting sale of 2 stocks of
MSFT. Total gain=
$240.97*2= $481.94. [00:04:000]Finished
signed sale of 2
stocks of MSFT.
Profit earned till
purchase of 5 stocks
of AMD. Total cost=
$89.58*5= $447.9.
[00:03.000] Finished purchase of 5 stocks
of AMD. Remaining balance= $740.26-
$447.9= $292.36.
[00:09:000] Assigned
sale of 1 stock of
MSFT. Total gain
estimate= $240.97*1=
$240.97.
[00:09:000] Assigned
purchase of 1 stock of MSFT. Total cost
estimate= $240.97*1=
$240.97.
[00:09:000] Starting
sale of 1 stock of
MSFT. Total gain=
$240.97*1= $240.97.
[00:10:000] Finished
sale of 1 stock of
MSFT. Profit earned
till now=
$129.87+$240.97=
$370.84.
[00:10:000] Starting
purchase of 1 stock
of MSFT. Total cost=
$240.97*1= $240.97.
[00:11:000] Finished
purchase of 1 stock
of MSFT. Remaining
balance= $292.36-
$240.97= $51.39.
[00:12:000] Assigned
sale of 3 stocks of
now=
$240.97+$481.94=
$722.91.
[00:09:000] Assigned purchase of 2 stocks
of TSLA. Total cost estimate= $781.3*2=
$1562.6.
[00:09:000] Starting purchase of 2 stocks of TSLA. Total cost=
$781.3*2= $1562.6.
[00:10:000] Finished purchase of 2 stocks
of TSLA. Remaining
balance= $2000-
$1562.6= $437.4.
7
TSLA. Total gain
estimate= $781.3*3=
$2343.9. Profit
earned till now= $370.84+$2343.9=
$2714.74.
[00:12:000] Starting
sale of 1 stock of
TSLA. Total gain=
$781.3*3= $2343.9.
[00:13:000] Finished
sale of 1 stock of
TSLA.
Incomplete
19)
[00:13:010]Incomplet e trades: (12, TSLA,
[00:13:010]Incomplet e trades: (12, TSLA,
1, 2021-02-19)
trades: (12,
1, 2021-02-19)
Total Profit Earned:
TSLA, 1, 2021-02-
Total Profit Earned:
$2714.74.
$722.91.
[00:13:010]
Processing
Grading Criteria
[00:13:010]
Processing complete!!
complete!
Processing complete!!
The way you go about implementing the solution is not specifically graded, but the
output must match exactly what you see in the execution above.
Networking (1.0%)
0.2% The first client can connect to the server
0.3% Only the number of clients, which is determined by the number of records in
traders.csv, can connect to the server.
0.5% Server output is correct
Data I/O (1.0%)
0.3% The schedule file and traders file are read appropriately
0.2% Data is parsed from the Tiingo API
0.5% Client output is correct
Program Execution (3.0%)
1.0% The order of deliveries is correct
1.0% The timing of deliveries is correct
1.0% Orders are delivered as expected with no exceptions, crashing, deadlock,
starvation, or freezing.
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