chore: remove packaging prerequisites requirements from build (#11691)

Split the prerequisites check for `pack` and `build`. Executing `build` does not execute pack, which means it does not require the tools for packaging (`mvn`, `python`, `.Net`, `java`) to be installed locally.

This PR splits `check-prerequisites` into two separate scripts, `check-build-prerequisites` and `check-pack-prerequisites`. 

For build check:
* `node`
* `yarn`
* `docker` (arguable, but fine)

For pack check:
* all build prerequisites
* `mvn`
* `java`
* `.Net`
* `python`



----

*By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license*

build.sh

@@ -56,7 +56,7 @@ fail() {
 
 # Verify all required tools are present before starting the build
 if [ "$check_prereqs" == "true" ]; then
-  /bin/bash ./scripts/check-prerequisites.sh
+  /bin/bash ./scripts/check-build-prerequisites.sh
 fi
 
 # Prepare for build with references

pack.sh

@@ -19,6 +19,10 @@ distdir="$PWD/dist"
 rm -fr ${distdir}
 mkdir -p ${distdir}
 
+if ${CHECK_PREREQS:-true}; then
+  /bin/bash ./scripts/check-pack-prerequisites.sh
+fi
+
 # Split out jsii and non-jsii packages. Jsii packages will be built all at once.
 # Non-jsii packages will be run individually.
 echo "Collecting package list..." >&2

scripts/check-build-prerequisites.sh

@@ -0,0 +1,91 @@
+#!/bin/bash
+set -euo pipefail
+
+scriptdir=$(cd $(dirname $0) && pwd)
+
+# Testing with this to simulate different installed apps:
+# docker run -it -v ~/Source/aws-cdk:/var/cdk ubuntu bash
+
+# Note: Don't use \d in regex, it doesn't work on Macs without GNU tools installed
+# Use [0-9] instead
+
+die() { echo "$*" 1>&2 ; exit 1; }
+wrong_version() { echo "Found $app version $app_v. Install $app >= $app_min" 1>&2; exit 1; }
+
+check_which() {
+    local app=$1
+    local min=$2
+
+    echo -e "Checking if $app is installed... \c"
+
+    w=$(which ${app}) || w=""
+
+    if [ -z "$w" ] || [ "$w" == "$app not found" ]
+    then
+        die "Missing dependency: $app. Install $app >= $min"
+    else
+        echo "Ok"
+    fi
+}
+
+app=""
+app_min=""
+app_v=""
+
+# [Node.js >= 10.13.0]
+#   ⚠️ versions `13.0.0` to `13.6.0` are not supported due to compatibility issues with our dependencies.
+app="node"
+app_min="v10.13.0"
+check_which $app $app_min
+app_v=$(node --version)
+
+# Check for version 10.*.* - 29.*.*
+echo -e "Checking node version... \c"
+if [ $(echo $app_v | grep -c -E "v[12][0-9]\.[0-9]+\.[0-9]+") -eq 1 ]
+then    
+    # Check for version 13.0 to 13.6
+    if [ $(echo $app_v | grep -c -E "v13\.[0-6]\.[0-9]+") -eq 1 ]
+    then
+        die "node versions 13.0.0 to 13.6.0 are not supported due to compatibility issues with our dependencies."
+    else
+        # Check for version < 10.13
+        if [ $(echo $app_v | grep -c -E "v10\.([0-9]|1[0-2])\.[0-9]+") -eq 1 ]
+        then   
+            wrong_version
+        else
+            echo "Ok"
+        fi
+    fi
+else    
+    echo "Not 12"
+    wrong_version
+fi
+
+# [Yarn >= 1.19.1, < 1.30]
+app="yarn"
+app_min="1.19.1"
+check_which $app $app_min
+app_v=$(${app} --version)
+echo -e "Checking yarn version... \c"
+if [ $(echo $app_v | grep -c -E "1\.(19|2[0-9])\.[0-9]+") -eq 1 ]
+then   
+    echo "Ok"
+else
+    wrong_version
+fi
+
+# [Docker >= 19.03]
+app="docker"
+app_min="19.03.0"
+check_which $app $app_min
+
+# Make sure docker is running
+echo -e "Checking if docker is running... \c"
+docker_running=$(docker ps)
+if [ $? -eq 0 ]
+then    
+    echo "Ok"
+else
+    die "Docker is not running"
+fi
+

scripts/check-prerequisites.sh → scripts/check-pack-prerequisites.sh

@@ -1,16 +1,15 @@
 #!/bin/bash
 set -euo pipefail
 
+scriptdir=$(cd $(dirname $0) && pwd)
+source ${scriptdir}/check-build-prerequisites.sh
+
 # Testing with this to simulate different installed apps:
 # docker run -it -v ~/Source/aws-cdk:/var/cdk ubuntu bash
 
 # Note: Don't use \d in regex, it doesn't work on Macs without GNU tools installed
 # Use [0-9] instead
 
-app=""
-app_min=""
-app_v=""
-
 die() { echo "$*" 1>&2 ; exit 1; }
 wrong_version() { echo "Found $app version $app_v. Install $app >= $app_min" 1>&2; exit 1; }
 
@@ -30,47 +29,9 @@ check_which() {
     fi
 }
 
-# [Node.js >= 10.13.0]
-#   ⚠️ versions `13.0.0` to `13.6.0` are not supported due to compatibility issues with our dependencies.
-app="node"
-app_min="v10.13.0"
-check_which $app $app_min
-app_v=$(node --version)
-
-# Check for version 10.*.* - 29.*.*
-echo -e "Checking node version... \c"
-if [ $(echo $app_v | grep -c -E "v[12][0-9]\.[0-9]+\.[0-9]+") -eq 1 ]
-then    
-    # Check for version 13.0 to 13.6
-    if [ $(echo $app_v | grep -c -E "v13\.[0-6]\.[0-9]+") -eq 1 ]
-    then
-        die "node versions 13.0.0 to 13.6.0 are not supported due to compatibility issues with our dependencies."
-    else
-        # Check for version < 10.13
-        if [ $(echo $app_v | grep -c -E "v10\.([0-9]|1[0-2])\.[0-9]+") -eq 1 ]
-        then   
-            wrong_version
-        else
-            echo "Ok"
-        fi
-    fi
-else    
-    echo "Not 12"
-    wrong_version
-fi
-
-# [Yarn >= 1.19.1, < 1.30]
-app="yarn"
-app_min="1.19.1"
-check_which $app $app_min
-app_v=$(${app} --version)
-echo -e "Checking yarn version... \c"
-if [ $(echo $app_v | grep -c -E "1\.(19|2[0-9])\.[0-9]+") -eq 1 ]
-then   
-    echo "Ok"
-else
-    wrong_version
-fi
+app=""
+app_min=""
+app_v=""
 
 # [Java OpenJDK 8, 11, 14]
 
@@ -143,19 +104,3 @@ then
 else
     wrong_version
 fi
-
-# [Docker >= 19.03]
-app="docker"
-app_min="19.03.0"
-check_which $app $app_min
-
-# Make sure docker is running
-echo -e "Checking if docker is running... \c"
-docker_running=$(docker ps)
-if [ $? -eq 0 ]
-then    
-    echo "Ok"
-else
-    die "Docker is not running"
-fi
-