This repository contains the starter code for project 1 (15-440, Fall 2019). It also contains the tests that we will use to grade your implementation, and two simple echo server/client (srunner and crunner, respectively) programs that you might find useful for your own testing purposes. These instructions assume you have set your GOPATH to point to the repository's root p1/ directory.

If at any point you have any trouble with building, installing, or testing your code, the article titled How to Write Go Code is a great resource for understanding how Go workspaces are built and organized. You might also find the documentation for the go command to be helpful. As always, feel free to post your questions on Piazza.

This project was designed for, and tested on AFS cluster machines, though you may choose to write and build your code locally as well.

To make testing your server a bit easier we have provided two simple echo server/client programs called srunner and crunner. If you look at the source code for the two programs, you’ll notice that they import the github.com/cmu440/lsp package (in other words, they compile against the current state of your LSP implementation). We believe you will find these programs useful in the early stages of development when your client and server implementations are largely incomplete.

To compile, build, and run these programs, use the go run command from inside the directory storing the file (these instructions assume your GOPATH is pointing to the project’s root p1/ directory):

go run srunner.go

The srunner and crunner programs may be customized using command line flags. For more information, specify the -h flag at the command line. For example,

$ go run srunner.go -h
Usage of bin/srunner:
  -elim=5: epoch limit
  -ems=2000: epoch duration (ms)
  -port=9999: port number
  -rdrop=0: network read drop percent
  -v=false: show srunner logs
  -wdrop=0: network write drop percent
  -wsize=1: window 
  -maxUnackMessages=1: maximum unacknowledged messages allowed
  -maxBackoff: maximum interval epoch

We have also provided pre-compiled executables for you to use called srunner-sols and crunner-sols. These binaries were compiled against our reference LSP implementation, so you might find them useful in the early stages of the development process (for example, if you wanted to test your Client implementation but haven’t finished implementing the Server yet, etc.). Two separate binaries are provided under each OS folder in bin.

As an example, to start an echo server on port 6060 on an AFS cluster machine, execute the following command:

$GOPATH/bin/linux_amd64/srunner-sols -port=6060

To test your submission, we will execute the following command from inside the p1/src/github.com/cmu440/lsp directory for each of the tests (where TestName is the name of one of the 44 test cases, such as TestBasic6 or TestWindow1):

go test -run=TestName

Note that we will execute each test individually using the -run flag and by specify a regular expression identifying the name of the test to run. To ensure that previous tests don’t affect the outcome of later tests, we recommend executing the tests individually (or in small batches, such as go test -run=TestBasic which will execute all tests beginning with TestBasic) as opposed to all together using go test.

On some tests, we will also check your code for race conditions using Go’s race detector:

go test -race -run=TestName

We have also provided Autolab test scripts mocks in sh/. When you are inside the p1/src/github.com/cmu440/lsp directory and execute corresponding script, you can have a rough sense of what your score should be like on Autolab.

As with project 0, we will be using Autolab to grade your submissions for this project. We will run some—but not all—of the tests with the race detector enabled.

To submit your code to Autolab, create a lsp.tar file containing your LSP implementation as follows:

cd p1/src/github.com/cmu440/
tar -cvf lsp.tar lsp/

Coming soon!

Before you begin the project, you should read and understand all of the starter code we provide. To make this experience a little less traumatic (we know, it's a lot :P), fire up a web server and read the documentation in a browser by executing the following command:

godoc -http=:6060 &

Then, navigate to localhost:6060/pkg/github.com/cmu440 in a browser. Note that you can execute this command from anywhere in your system (assuming your GOPATH is pointing to the project's root p1/ directory).