move WEB_CONCURRENCY logic to separate file (#467)

All buildpacks use `profile/WEB_CONCURRENCY.sh` now which will be overwritten by the later buildpacks to avoid earlier buildpacks setting defaults for later ones at startup, with wrong defaults for some languages.

profile/WEB_CONCURRENCY.sh

+#!/usr/bin/env bash
+
+calculate_concurrency() {
+  WEB_CONCURRENCY=${WEB_CONCURRENCY-$((MEMORY_AVAILABLE/WEB_MEMORY))}
+  if (( WEB_CONCURRENCY < 1 )); then
+    WEB_CONCURRENCY=1
+  fi
+  echo $WEB_CONCURRENCY
+}
+
+log_concurrency() {
+  echo "Detected $MEMORY_AVAILABLE MB available memory, $WEB_MEMORY MB limit per process (WEB_MEMORY)"
+  echo "Recommending WEB_CONCURRENCY=$WEB_CONCURRENCY"
+}
+
+detect_memory() {
+  local default=$1
+  local limit=$(ulimit -u)
+
+  case $limit in
+    256) echo "512";;      # Standard-1X
+    512) echo "1024";;     # Standard-2X
+    16384) echo "2560";;   # Performance-M
+    32768) echo "14336";;  # Performance-L
+    *) echo "$default";;
+  esac
+}
+
+export MEMORY_AVAILABLE=${MEMORY_AVAILABLE-$(detect_memory 512)}
+export WEB_MEMORY=${WEB_MEMORY-512}
+export WEB_CONCURRENCY=$(calculate_concurrency)
+
+if [ "$LOG_CONCURRENCY" = "true" ]; then
+  log_concurrency
+fi

profile/nodejs.sh

-calculate_concurrency() {
-  MEMORY_AVAILABLE=${MEMORY_AVAILABLE-$(detect_memory 512)}
-  WEB_MEMORY=${WEB_MEMORY-512}
-  WEB_CONCURRENCY=${WEB_CONCURRENCY-$((MEMORY_AVAILABLE/WEB_MEMORY))}
-  if (( WEB_CONCURRENCY < 1 )); then
-    WEB_CONCURRENCY=1
-  fi
-  WEB_CONCURRENCY=$WEB_CONCURRENCY
-}
-
-log_concurrency() {
-  echo "Detected $MEMORY_AVAILABLE MB available memory, $WEB_MEMORY MB limit per process (WEB_MEMORY)"
-  echo "Recommending WEB_CONCURRENCY=$WEB_CONCURRENCY"
-}
-
-detect_memory() {
-  local default=$1
-  local limit=$(ulimit -u)
-
-  case $limit in
-    256) echo "512";;      # Standard-1X
-    512) echo "1024";;     # Standard-2X
-    16384) echo "2560";;   # Performance-M
-    32768) echo "14336";;  # Performance-L
-    *) echo "$default";;
-  esac
-}
-
 export PATH="$HOME/.heroku/node/bin:$HOME/.heroku/yarn/bin:$PATH:$HOME/bin:$HOME/node_modules/.bin"
 export NODE_HOME="$HOME/.heroku/node"
 export NODE_ENV=${NODE_ENV:-production}
-
-calculate_concurrency
-
-export MEMORY_AVAILABLE=$MEMORY_AVAILABLE
-export WEB_MEMORY=$WEB_MEMORY
-export WEB_CONCURRENCY=$WEB_CONCURRENCY
-
-if [ "$LOG_CONCURRENCY" = "true" ]; then
-  log_concurrency
-fi

test/run

@@ -326,35 +326,35 @@ testBuildWithUserCacheDirectoriesCamel() {
 }
 
 testConcurrency1X() {
-  LOG_CONCURRENCY=true MEMORY_AVAILABLE=512 capture $(pwd)/profile/nodejs.sh
+  LOG_CONCURRENCY=true MEMORY_AVAILABLE=512 capture $(pwd)/profile/WEB_CONCURRENCY.sh
   assertCaptured "Detected 512 MB available memory, 512 MB limit per process (WEB_MEMORY)"
   assertCaptured "Recommending WEB_CONCURRENCY=1"
   assertCapturedSuccess
 }
 
 testConcurrency2X() {
-  LOG_CONCURRENCY=true MEMORY_AVAILABLE=1024 capture $(pwd)/profile/nodejs.sh
+  LOG_CONCURRENCY=true MEMORY_AVAILABLE=1024 capture $(pwd)/profile/WEB_CONCURRENCY.sh
   assertCaptured "Detected 1024 MB available memory, 512 MB limit per process (WEB_MEMORY)"
   assertCaptured "Recommending WEB_CONCURRENCY=2"
   assertCapturedSuccess
 }
 
 testConcurrencyPerformanceM() {
-  LOG_CONCURRENCY=true MEMORY_AVAILABLE=2560 capture $(pwd)/profile/nodejs.sh
+  LOG_CONCURRENCY=true MEMORY_AVAILABLE=2560 capture $(pwd)/profile/WEB_CONCURRENCY.sh
   assertCaptured "Detected 2560 MB available memory, 512 MB limit per process (WEB_MEMORY)"
   assertCaptured "Recommending WEB_CONCURRENCY=5"
   assertCapturedSuccess
 }
 
 testConcurrencyPerformanceL() {
-   LOG_CONCURRENCY=true MEMORY_AVAILABLE=14336 capture $(pwd)/profile/nodejs.sh
+   LOG_CONCURRENCY=true MEMORY_AVAILABLE=14336 capture $(pwd)/profile/WEB_CONCURRENCY.sh
    assertCaptured "Detected 14336 MB available memory, 512 MB limit per process (WEB_MEMORY)"
    assertCaptured "Recommending WEB_CONCURRENCY=28"
    assertCapturedSuccess
 }
 
 testConcurrencyCustomLimit() {
-  LOG_CONCURRENCY=true MEMORY_AVAILABLE=1024 WEB_MEMORY=256 capture $(pwd)/profile/nodejs.sh
+  LOG_CONCURRENCY=true MEMORY_AVAILABLE=1024 WEB_MEMORY=256 capture $(pwd)/profile/WEB_CONCURRENCY.sh
   assertCaptured "Detected 1024 MB available memory, 256 MB limit per process (WEB_MEMORY)"
   assertCaptured "Recommending WEB_CONCURRENCY=4"
   assertCapturedSuccess