fatal error: concurrent map writes

[liorlevtov]

Expected Behavior

Opa should not panic and exist

Actual Behavior

panics

Steps to Reproduce the Problem

1. during everyday operation we saw panic in the log

Additional Info

attached the whole stack trace that OPA
OPA_Full_trace.txt

[tsandall]

I think this is caused by this change: 66fb55f#diff-304927c4591ee459ab6e909666e945d0R662. The server goroutines share an instance of the compiler. On this line the compiler's map could be modified concurrently. I'll review the calling code and figure out the right solution.

EDIT:

Here is a small test case for the server that reproduces the issue:

func TestConcurrentQuery(t *testing.T) {

	fixture := newFixture(t)

	var wg sync.WaitGroup

	for i := 0; i < 4; i++ {
		wg.Add(1)
		go func() {
			for x := 0; x < 10000; x++ {
				if err := fixture.v1("POST", "/data", "", 200, ``); err != nil {
					t.Fatal(err)
				}
			}
			wg.Done()
		}()
	}

	wg.Wait()
}