From fb827907691cddfd7b332bbc98f36262d0cb8fea Mon Sep 17 00:00:00 2001
From: Eduardo Poleo <eduardopoleo@gmail.com>
Date: Wed, 9 Jan 2019 23:14:39 -0500
Subject: [PATCH] Launcher script breaks at high numbers of sites (#414)

On a multi-site app configuration files such as containers/web.yml
grow with the number of sites. We discovered that the launcher script breaks
at around 100 sites due to "Argument List too long" when
commands such 'echo' are being referenced from the within the exec
call.

This workaround echoes the "$input" content outside the exec (which we verified
works fine for 300 sites) and then cats the file content inside the
exec. Thus bypassing the argument limitation. Finally, we remove the temporary file generated.
---
 launcher | 22 +++++++++++++++++++---
 1 file changed, 19 insertions(+), 3 deletions(-)

diff --git a/launcher b/launcher
index 4c16489..06588fd 100755
--- a/launcher
+++ b/launcher
@@ -335,7 +335,12 @@ set_template_info() {
     puts env.map{|k,v| "-e\n#{k}=#{v}" }.join("\n")
 RUBY
 
-    raw=`exec echo "$input" | $docker_path run $user_args --rm -i -a stdin -a stdout $image ruby -e "$env_ruby"`
+    tmp_input_file=$(mktemp)
+
+    echo "$input" > "$tmp_input_file"
+    raw=`exec cat "$tmp_input_file" | $docker_path run $user_args --rm -i -a stdin -a stdout $image ruby -e "$env_ruby"`
+
+    rm -f "$tmp_input_file"
 
     env=()
     ok=1
@@ -374,7 +379,12 @@ RUBY
     puts labels.map{|k,v| "-l\n#{k}=#{v}" }.join("\n")
 RUBY
 
-    raw=`exec echo "$input" | $docker_path run $user_args --rm -i -a stdin -a stdout $image ruby -e "$labels_ruby"`
+    tmp_input_file=$(mktemp)
+
+    echo "$input" > "$tmp_input_file"
+    raw=`exec cat "$tmp_input_file" | $docker_path run $user_args --rm -i -a stdin -a stdout $image ruby -e "$labels_ruby"`
+
+    rm -f "$tmp_input_file"
 
     labels=()
     ok=1
@@ -622,9 +632,15 @@ run_bootstrap() {
   echo $run_command
 
   unset ERR
-  (exec echo "$input" | $docker_path run --shm-size=512m $user_args $links "${env[@]}" -e DOCKER_HOST_IP="$docker_ip" --cidfile $cidbootstrap -i -a stdin -a stdout -a stderr $volumes $image \
+
+  tmp_input_file=$(mktemp)
+
+  echo "$input" > "$tmp_input_file"
+  (exec cat "$tmp_input_file" | $docker_path run --shm-size=512m $user_args $links "${env[@]}" -e DOCKER_HOST_IP="$docker_ip" --cidfile $cidbootstrap -i -a stdin -a stdout -a stderr $volumes $image \
     /bin/bash -c "$run_command") || ERR=$?
 
+  rm -f "$tmp_input_file"
+
   unset FAILED
   # magic exit code that indicates a retry
   if [[ "$ERR" == 77 ]]; then
-- 
2.25.1