Surround regexps with ^ and $

prog/weaveproxy/main.go

@@ -51,7 +51,7 @@ func main() {
 	mflag.BoolVar(&justVersion, []string{"#version", "-version"}, false, "print version and exit")
 	mflag.StringVar(&logLevel, []string{"-log-level"}, "info", "logging level (debug, info, warning, error)")
 	ListVar(&c.ListenAddrs, []string{"H"}, defaultListenAddrs, "addresses on which to listen")
-	mflag.StringVar(&c.Hostname, []string{"-hostname"}, "/(.*)/$1/", "Regexp substitution to apply on container names (e.g. '/aws-[0-9]+-(.*)/my-app-$1/')")
+	mflag.StringVar(&c.Hostname, []string{"-hostname"}, "/^(.*)$/$1/", "Regexp substitution to apply on container names (e.g. '/^aws-[0-9]+-(.*)$/my-app-$1/')")
 	mflag.BoolVar(&c.NoDefaultIPAM, []string{"#-no-default-ipam", "-no-default-ipalloc"}, false, "do not automatically allocate addresses for containers without a WEAVE_CIDR")
 	mflag.BoolVar(&c.NoRewriteHosts, []string{"no-rewrite-hosts"}, false, "do not automatically rewrite /etc/hosts. Use if you need the docker IP to remain in /etc/hosts")
 	mflag.StringVar(&c.TLSConfig.CACert, []string{"#tlscacert", "-tlscacert"}, "", "Trust certs signed only by this CA")

site/proxy.md

@@ -140,9 +140,9 @@ For those situations, the proxy provides a
 `/containerNamePattern/hostnameReplacement/` is a regular expression
 substitution command.
 
-For instance, if we launch the proxy using `--hostname='/aws-[0-9]+-(.*)/my-app-$1/'`
+For instance, if we launch the proxy using `--hostname='/^aws-[0-9]+-(.*)$/my-app-$1/'`
 
-    host1$ weave launch-router && weave launch-dns && weave launch-proxy --hostname='/aws-[0-9]+-(.*)/my-app-$1/'
+    host1$ weave launch-router && weave launch-dns && weave launch-proxy --hostname='/^aws-[0-9]+-(.*)$/my-app-$1/'
     host1$ eval "$(weave env)"
 
 then, running a container named `aws-12798186823-foo` will lead to weaveDNS registering

test/680_proxy_hostname_derivation.sh

@@ -19,7 +19,7 @@ start_container() {
 start_suite "Hostname derivation through container name substitutions"
 
 weave_on $HOST1 launch-dns 10.2.254.1/24
-weave_on $HOST1 launch-proxy --hostname '/[^-]+-(?P<appname>[^-]*)-[^-]+/$appname/'
+weave_on $HOST1 launch-proxy --hostname '/^[^-]+-(?P<appname>[^-]*)-[^-]+$/$appname/'
 
 start_container -e WEAVE_CIDR=$C1/24 --name=$CNAME1
 start_container -e WEAVE_CIDR=$C2/24 --name=$CNAME2