From 7cf717bc7f895fc099ff5d8d7b757b9a355204c2 Mon Sep 17 00:00:00 2001
From: Nick Josevski <nick.josevski@octopus.com>
Date: Thu, 6 Aug 2026 16:10:26 +1000
Subject: [PATCH] Make the build.sh SDK bootstrap diagnosable, and stop
 assuming curl and perl

build.sh uses the machine's dotnet if `dotnet --version` succeeds, and otherwise
downloads an SDK. That fallback shells out to curl and perl, neither of which is
guaranteed in our Linux execution containers, so the first symptom is an opaque
`exit 127` from a missing tool.

That misleads twice over: reaching the fallback at all means `dotnet --version`
failed, which is almost always global.json pinning an SDK the machine does not
have. The "command not found" points away from the cause.

- Log why the bootstrap ran, and list the SDKs that are installed
- Use wget when curl is absent; name the problem when neither exists
- Use sed when perl is absent

Verified with the SDK install stubbed, in the containers that actually broke:
amazonlinux:2 (curl, no perl) and debian:12 +wget (no curl) now complete the
bootstrap instead of exiting 127; with neither downloader present it fails with
a named error; and SDK 8 against a global.json pinning 10.0.302 now reports
"global.json likely pins an SDK that is not installed (found: 8.0.423)".

The sed fallback returns 8.0.419 for this repo's global.json, matching perl. A
machine that already satisfies global.json still skips the bootstrap entirely.

Deliberately out of scope: the hardcoded DOTNET_CHANNEL="8.0" (belongs with the
.NET 10 work), and build.ps1 (Windows ships curl.exe and needs no perl).

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
---
 build.sh | 40 ++++++++++++++++++++++++++++++++++++++--
 1 file changed, 38 insertions(+), 2 deletions(-)

diff --git a/build.sh b/build.sh
index 1089acffb9..f10b818403 100755
--- a/build.sh
+++ b/build.sh
@@ -24,17 +24,53 @@ export DOTNET_MULTILEVEL_LOOKUP=0
 ###########################################################################
 
 function FirstJsonValue {
-    perl -nle 'print $1 if m{"'"$1"'": "([^"]+)",?}' <<< "${@:2}"
+    # Stock Nuke shells out to perl. The Amazon Linux execution container does not ship it, so fall
+    # back to sed rather than dying with "perl: command not found".
+    if command -v perl &>/dev/null; then
+        perl -nle 'print $1 if m{"'"$1"'": "([^"]+)",?}' <<< "${@:2}"
+    else
+        sed -n 's/.*"'"$1"'"[[:space:]]*:[[:space:]]*"\([^"]*\)".*/\1/p' <<< "${@:2}" | head -n 1
+    fi
+}
+
+# ----- Octopus Deploy Modification -----
+# Stock Nuke assumes curl. The Linux execution containers install wget instead
+function DownloadFile {
+    local url="$1"
+    local destination="$2"
+
+    if command -v curl &>/dev/null; then
+        curl -Lsfo "$destination" "$url"
+    elif command -v wget &>/dev/null; then
+        wget -qO "$destination" "$url"
+    else
+        echo "Unable to download $url - neither curl nor wget is available on this machine." >&2
+        return 1
+    fi
+}
+
+# Without this you get "command not found", makes you think missing tool but it's actually missing SDK
+function DotnetBootstrapReason {
+    if [[ ! -x "$(command -v dotnet)" ]]; then
+        echo "no 'dotnet' found on PATH"
+    else
+        local installed
+        installed=$(dotnet --list-sdks 2>/dev/null | cut -d' ' -f1 | paste -sd' ' -)
+        echo "'dotnet --version' failed - global.json likely pins an SDK that is not installed (found: ${installed:-none})"
+    fi
 }
+# ----- End Octopus Deploy Modification -----
 
 # If dotnet CLI is installed globally and it matches requested version, use for execution
 if [ -x "$(command -v dotnet)" ] && dotnet --version &>/dev/null; then
     export DOTNET_EXE="$(command -v dotnet)"
 else
+    echo "Bootstrapping a local .NET SDK: $(DotnetBootstrapReason)"
+
     # Download install script
     DOTNET_INSTALL_FILE="$TEMP_DIRECTORY/dotnet-install.sh"
     mkdir -p "$TEMP_DIRECTORY"
-    curl -Lsfo "$DOTNET_INSTALL_FILE" "$DOTNET_INSTALL_URL"
+    DownloadFile "$DOTNET_INSTALL_URL" "$DOTNET_INSTALL_FILE"
     chmod +x "$DOTNET_INSTALL_FILE"
 
     # If global.json exists, load expected version