wait for elasticsearch to be ready in travis

If the prereq installation happens fast enough, such as if it is pulling
from cache, Elasticsearch may not be fully started by the time the tests
start running.  Do a simple check for if it is up, waiting up to 30
seconds, before proceeding.

Author: haarg

.travis.yml

@@ -71,6 +71,7 @@ install:
 
 before_script:
   - "perl -i -pe 's/(servers :)9900/localhost:9200/' metacpan_server_testing.conf"
+  - bin/wait-for-open http://localhost:9200/
   - coverage-setup
 
 script:

bin/wait-for-open

@@ -0,0 +1,16 @@
+#!/usr/bin/env perl
+use strict;
+use warnings;
+
+my $server = shift;
+
+my $timeout = 30;
+while ($timeout--) {
+    if (!system "curl -s '$server' 2>/dev/null 1>&2") {
+        exit 0;
+    }
+    sleep 1;
+}
+
+print STDERR "Timed out starting elasticsearch!\n";
+exit 1;