really fix netcat race

We hit this once every few Jenkins runs. This:

1. Ensures netcat has started before we try to use it.
2. Waits for it to actually write the request before trying to read it.

License: MIT
Signed-off-by: Steven Allen <steven@stebalien.com>

test/sharness/t0235-cli-request.sh

@@ -10,11 +10,43 @@ test_description="test http requests made by cli"
 
 test_init_ipfs
 
-test_expect_success "can make http request against nc server" '
-  nc -ld 5005 > nc_out &
+test_expect_success "start nc" '
+  rm -f nc_out nc_outp nc_inp && mkfifo nc_inp nc_outp
+
+  nc -k -l 127.0.0.1 5005 <nc_inp >nc_outp &
   NCPID=$!
-  go-sleep 0.5s && kill "$NCPID" &
-  ipfs cat /ipfs/Qmabcdef --api /ip4/127.0.0.1/tcp/5005 || true
+
+  exec 6>nc_inp 7<nc_outp
+
+  while ! nc -z 127.0.0.1 5005; do
+    go-sleep 100ms
+  done
+'
+
+test_expect_success "can make http request against nc server" '
+  ipfs cat /ipfs/Qmabcdef --api /ip4/127.0.0.1/tcp/5005 &
+  IPFSPID=$!
+
+  # handle request
+  while read line; do
+    if [[ "$line" == "$(echo -e "\r")" ]]; then
+      break
+    fi
+    echo "$line"
+  done <&7 >nc_out &&
+
+  echo -e "HTTP/1.1 200 OK\r" >&6 &&
+  echo -e "Content-Type: text/plain\r" >&6 &&
+  echo -e "Content-Length: 0\r" >&6 &&
+  echo -e "\r" >&6 &&
+  exec 6<&- &&
+
+  # Wait for IPFS
+  wait $IPFSPID
+'
+
+test_expect_success "stop nc" '
+  kill "$NCPID" && wait "$NCPID" || true
 '
 
 test_expect_success "output does not contain multipart info" '

test/sharness/t0236-cli-api-dns-resolve.sh

@@ -10,11 +10,43 @@ test_description="test dns resolution of api endpoint by cli"
 
 test_init_ipfs
 
-test_expect_success "can make http request against dns resolved nc server" '
-  nc -ld 5005 > nc_out &
+test_expect_success "start nc" '
+  rm -f nc_out nc_outp nc_inp && mkfifo nc_inp nc_outp
+
+  nc -k -l 127.0.0.1 5006 <nc_inp >nc_outp &
   NCPID=$!
-  go-sleep 1s && kill "$NCPID" &
-  ipfs cat /ipfs/Qmabcdef --api /dns4/localhost/tcp/5005 || true
+
+  exec 6>nc_inp 7<nc_outp
+
+  while ! nc -z 127.0.0.1 5006; do
+    go-sleep 100ms
+  done
+'
+
+test_expect_success "can make http request against dns resolved nc server" '
+  ipfs cat /ipfs/Qmabcdef --api /dns4/localhost/tcp/5006 &
+  IPFSPID=$!
+
+  # handle request
+  while read line; do
+    if [[ "$line" == "$(echo -e "\r")" ]]; then
+      break
+    fi
+    echo "$line"
+  done <&7 >nc_out &&
+
+  echo -e "HTTP/1.1 200 OK\r" >&6 &&
+  echo -e "Content-Type: text/plain\r" >&6 &&
+  echo -e "Content-Length: 0\r" >&6 &&
+  echo -e "\r" >&6 &&
+  exec 6<&- &&
+
+  # Wait for IPFS
+  wait $IPFSPID
+'
+
+test_expect_success "stop nc" '
+  kill "$NCPID" && wait "$NCPID" || true
 '
 
 test_expect_success "request was received by local nc server" '