build: support dd-trace package override and filter publish layer check

Dockerfile

@@ -1,13 +1,17 @@
 ARG image
 FROM $image AS builder
 ARG image
+ARG dd_trace_package
 
 # Create the directory structure required for AWS Lambda Layer
 RUN mkdir -p /nodejs/node_modules/
 
 # Install dev dependencies
 COPY . datadog-lambda-js
 WORKDIR /datadog-lambda-js
+RUN if [ -n "$dd_trace_package" ]; then \
+    node -e 'const fs = require("fs"); const pkg = JSON.parse(fs.readFileSync("package.json", "utf8")); const spec = process.argv[1]; if (pkg.devDependencies && pkg.devDependencies["dd-trace"]) { pkg.devDependencies["dd-trace"] = spec; } else { pkg.dependencies = pkg.dependencies || {}; pkg.dependencies["dd-trace"] = spec; } fs.writeFileSync("package.json", JSON.stringify(pkg, null, 2) + "\n");' "$dd_trace_package"; \
+    fi
 RUN yarn install
 
 # Build the lambda layer

scripts/build_layers.sh

@@ -6,6 +6,21 @@
 # Copyright 2019 Datadog, Inc.
 
 # Builds Datadog node layers for lambda functions, using Docker
+#
+# Usage:
+#   NODE_VERSION=20.19 ./scripts/build_layers.sh
+#
+# dd-trace-js overrides (highest priority first):
+#   DD_TRACE_PACKAGE       Exact package spec to use for dd-trace.
+#   DD_TRACE_COMMIT        Specific dd-trace-js commit SHA to build from GitHub.
+#   DD_TRACE_COMMIT_BRANCH dd-trace-js branch name to build from GitHub.
+#
+# Examples:
+#   # Build a single layer for Node 20
+#   NODE_VERSION=20.19 ./scripts/build_layers.sh
+#
+#   # Build a single layer with dd-trace from a branch
+#   DD_TRACE_COMMIT_BRANCH=joey/cross-invocation-tracecontext-propagation NODE_VERSION=20.19 ./scripts/build_layers.sh
 set -e
 
 LAYER_DIR=".layers"
@@ -27,6 +42,21 @@ else
     fi
 fi
 
+function resolve_dd_trace_package {
+    if [ -n "$DD_TRACE_PACKAGE" ]; then
+        echo "$DD_TRACE_PACKAGE"
+    elif [ -n "$DD_TRACE_COMMIT" ]; then
+        echo "git+https://github.com/DataDog/dd-trace-js.git#$DD_TRACE_COMMIT"
+    elif [ -n "$DD_TRACE_COMMIT_BRANCH" ]; then
+        echo "git+https://github.com/DataDog/dd-trace-js.git#$DD_TRACE_COMMIT_BRANCH"
+    fi
+}
+
+DD_TRACE_PACKAGE_SPEC=$(resolve_dd_trace_package)
+if [ -n "$DD_TRACE_PACKAGE_SPEC" ]; then
+    echo "Using dd-trace package spec: $DD_TRACE_PACKAGE_SPEC"
+fi
+
 function make_path_absolute {
     echo "$(cd "$(dirname "$1")"; pwd)/$(basename "$1")"
 }
@@ -40,7 +70,9 @@ function docker_build_zip {
     # between different node runtimes.
     temp_dir=$(mktemp -d)
     docker buildx build -t datadog-lambda-layer-node:$1 . --no-cache \
-        --build-arg image=registry.ddbuild.io/images/mirror/node:${node_image_version}-bullseye --progress=plain -o $temp_dir/nodejs
+        --build-arg image=registry.ddbuild.io/images/mirror/node:${node_image_version}-bullseye \
+        --build-arg dd_trace_package="$DD_TRACE_PACKAGE_SPEC" \
+        --progress=plain -o $temp_dir/nodejs
 
     # Zip to destination, and keep directory structure as based in $temp_dir
     (cd $temp_dir && zip -q -r $destination ./)

scripts/publish_layers.sh

@@ -31,15 +31,6 @@ if [[ ${#LAYER_PATHS[@]} -ne $expected_length ]] || \
     exit 1
 fi
 
-# Check that the layer files exist
-for layer_file in "${LAYER_PATHS[@]}"
-do
-    if [ ! -f $layer_file  ]; then
-        echo "Could not find $layer_file."
-        exit 1
-    fi
-done
-
 # Determine the target regions
 if [ -z "$REGIONS" ]; then
     echo "Region not specified, running for all available regions."
@@ -78,6 +69,19 @@ else
     echo "Layer version specified: $VERSION"
 fi
 
+# Check that the layer files exist for the layers we'll actually publish
+for layer_name in "${LAYERS[@]}"; do
+    for i in "${!AVAILABLE_LAYERS[@]}"; do
+        if [[ "${AVAILABLE_LAYERS[$i]}" = "${layer_name}" ]]; then
+            layer_file="${LAYER_PATHS[$i]}"
+            if [ ! -f "$layer_file" ]; then
+                echo "Could not find $layer_file."
+                exit 1
+            fi
+        fi
+    done
+done
+
 read -p "Ready to publish version $VERSION of layers ${LAYERS[*]} to regions ${REGIONS[*]} (y/n)?" CONT
 if [ "$CONT" != "y" ]; then
     echo "Exiting"