feat: add implementation of init and invocation errors (#10)

Author: skunxicat

runtime/bootstrap

@@ -1,12 +1,48 @@
 #!/bin/sh
 
 # https://docs.aws.amazon.com/lambda/latest/dg/runtimes-walkthrough.html
+# https://docs.aws.amazon.com/lambda/latest/dg/runtimes-api.html
 
-# set -euo pipefail
 set -eo pipefail
 
+# Function to send initialization error
+send_init_error() {
+  local error_message="$1"
+  curl -sS -X POST \
+    "http://${AWS_LAMBDA_RUNTIME_API}/2018-06-01/runtime/init/error" \
+    -H "Content-Type: application/json" \
+    -d '{"errorMessage": "'"$error_message"'", "errorType": "Runtime.InitError"}'
+  exit 1
+}
+
+# Function to send invocation error
+send_invocation_error() {
+  local request_id="$1"
+  local error_message="$2"
+  curl -sS -X POST \
+    "http://${AWS_LAMBDA_RUNTIME_API}/2018-06-01/runtime/invocation/${request_id}/error" \
+    -H "Content-Type: application/json" \
+    -d '{"errorMessage": "'"$error_message"'", "errorType": "Runtime.HandlerError"}'
+}
+
 # Initialization - load function handler
-source $LAMBDA_TASK_ROOT/"$(echo $_HANDLER | cut -d. -f1).sh"
+if [ -z "$_HANDLER" ]; then
+  send_init_error "Handler not specified"
+fi
+
+HANDLER_FILE="$(echo $_HANDLER | cut -d. -f1).sh"
+HANDLER_FUNC="$(echo $_HANDLER | cut -d. -f2)"
+
+if [ ! -f "$LAMBDA_TASK_ROOT/$HANDLER_FILE" ]; then
+  send_init_error "Handler file not found: $HANDLER_FILE"
+fi
+
+source "$LAMBDA_TASK_ROOT/$HANDLER_FILE" || send_init_error "Failed to source handler file: $HANDLER_FILE"
+
+# Check if handler function exists
+if ! type "$HANDLER_FUNC" >/dev/null 2>&1; then
+  send_init_error "Handler function not found: $HANDLER_FUNC"
+fi
 
 # Processing
 while true
@@ -18,12 +54,17 @@ do
   # Extract request ID by scraping response headers received above
   REQUEST_ID=$(grep -Fi Lambda-Runtime-Aws-Request-Id "$HEADERS" | tr -d '[:space:]' | cut -d: -f2)
 
-  # Run the handler function from the script
-  RESPONSE=$($(echo "$_HANDLER" | cut -d. -f2) "$EVENT_DATA")
-
-
-  echo "$RESPONSE" | curl -sS -X POST \
-    "http://${AWS_LAMBDA_RUNTIME_API}/2018-06-01/runtime/invocation/${REQUEST_ID}/response" \
-    -H "Content-Type: application/json" \
-    -d @-
+  # Run the handler function from the script with error handling
+  if RESPONSE=$("$HANDLER_FUNC" "$EVENT_DATA" 2>&1); then
+    # Success - send response
+    echo "$RESPONSE" | curl -sS -X POST \
+      "http://${AWS_LAMBDA_RUNTIME_API}/2018-06-01/runtime/invocation/${REQUEST_ID}/response" \
+      -H "Content-Type: application/json" \
+      -d @-
+  else
+    # Error - send error response
+    send_invocation_error "$REQUEST_ID" "Handler function failed: $RESPONSE"
+  fi
+  
+  rm -f "$HEADERS"
 done