The test broke because Node lowered the maximum header size to defend
against large headers ( CVE-2018-12121 ).
In the test, we do actually want to pass large headers, because all
processing in CORS Anywhere is based on headers (the request body would
just be forwarded to the destination server).
The test failed intermittently with ECONNRESET or "socket hang up"
because the server (under test) would close the socket upon receiving
a request with too large request headers.
Starting from Node 12, the test started to fail because of
intermittent socket errors, such as ECONNRESET and "socket hang up".
Destroying the response before triggering a new request resolves it.
Node.js has forbidden header names with spaces in
6192c9892f.
The next error is thrown when the test sets the "some header" header:
Uncaught TypeError: Header name must be a valid HTTP Token ["some header"]
To fix it, replace spaces with dashes.
Using the performNRequests, I collected the following statistics
before choosing the maximum allowed "leaked" memory.
Node.js 0.12.2,
Using the http module ('use-http-instead-of-cors-anywhere'):
Memory usage delta: 132800 (100 requests of 50 kb each, 250ms)
Memory usage delta: 110144 (100 requests of 1 kb each, 172ms)
Memory usage delta: 709936 (1000 requests of 1 kb each, 902ms)
Memory usage delta: 865104 (10000 requests of 1 kb each, 7073ms)
Memory usage delta: 930416 (100000 requests of 1 kb each, 62856ms)
Using CORS Anywhere:
Memory usage delta: 356784 (100 requests of 50 kb each, 1004ms)
Memory usage delta: 355248 (100 requests of 1 kb each, 641ms)
Memory usage delta: 1326856 (1000 requests of 1 kb each, 3338ms)
Memory usage delta: 1462584 (10000 requests of 1 kb each, 21186ms)
Memory usage delta: 1473624 (100000 requests of 1 kb each, 211202ms)
Clearly, there is a small leak, but it is not proportional/linear
in terms of the number of requests, so the observed "leak" is probably
not an issue. Furthermore, the "leak" also occurs with the plain
http module.
After setting fixed limits, I ran the tests on Node.js 0.10.25 and
observed that the tests failed due to the too low limits, so I
incremented the limits (400 -> 550, 1500 -> 2000).
