datadog_wrapper

#!/bin/bash

# This is a wrapper script that is intended be used in conjunction with the
# AWS_LAMBDA_EXEC_WRAPPER environment variable on an AWS Lambda function. It
# enables universal instrumentation support for our Java and .NET runtimes.

args=("$@")

# lowercase DD_LOG_LEVEL
DD_LOG_LEVEL=$(echo "$DD_LOG_LEVEL" | tr '[:upper:]' '[:lower:]')

# debug_log is a variadic function that prints a message to stdout if the log level is debug
debug_log() {
  if [ "$DD_LOG_LEVEL" == "debug" ]
  then
    echo "[datadog-wrapper]" "$@"
  fi
}

DD_SERVERLESS_APPSEC_ENABLED=$(echo "$DD_SERVERLESS_APPSEC_ENABLED" | tr '[:upper:]' '[:lower:]')

if [ "$DD_EXPERIMENTAL_ENABLE_PROXY" == "true" ] || [[ "$DD_SERVERLESS_APPSEC_ENABLED" =~ ^(1|t|true)$ ]]
then
  debug_log "Enabling Datadog's Runtime API proxy"
  debug_log "The original AWS_LAMBDA_RUNTIME_API value is $AWS_LAMBDA_RUNTIME_API"

  # Replace the Runtime API address with the proxy address of the extension
  export AWS_LAMBDA_RUNTIME_API="127.0.0.1:9000"

  debug_log "Rerouting AWS_LAMBDA_RUNTIME_API to the Datadog extension at $AWS_LAMBDA_RUNTIME_API"
fi

if [[ "$DD_SERVERLESS_APPSEC_ENABLED" =~ ^(1|t|true)$ ]]
then
  debug_log "Enabling Datadog Application Security Management"

  # Enable the library's instrumentation telemetry needed for ASM OSS VM
  export DD_INSTRUMENTATION_TELEMETRY_ENABLED="${DD_INSTRUMENTATION_TELEMETRY_ENABLED:-true}" # the standard env var to enable telemetry
  export DD_TRACE_TELEMETRY_ENABLED="${DD_TRACE_TELEMETRY_ENABLED:-true}" # but dd-trace-js < v4.18.0 uses this other one

  # Automatically enable the library's APM tracing required by ASM in order to slightly ease the onboarding experience
  export DD_TRACE_ENABLED="true"
fi

debug_log "The runtime is $AWS_EXECUTION_ENV"

# Disable DD_TRACE_STATS_COMPUTATION_ENABLED by default for Java and .NET runtimes
export DD_TRACE_STATS_COMPUTATION_ENABLED="${DD_TRACE_STATS_COMPUTATION_ENABLED:-false}"

debug_log "DD_TRACE_STATS_COMPUTATION_ENABLED: $DD_TRACE_STATS_COMPUTATION_ENABLED"

# if it is .NET
if [[ "$AWS_EXECUTION_ENV" == *"dotnet"* ]]
then
  debug_log "Configuring for the .NET runtime!"

  if [ -z "$CORECLR_PROFILER_PATH" ]; then
    # CORECLR_PROFILER_PATH is not set, try to find the library in these paths, in order:
    PROFILER_PATHS=(
      # use the shared loader if it's present
      "/opt/datadog/linux-x64/Datadog.Trace.ClrProfiler.Native.so"
      "/opt/datadog/linux-arm64/Datadog.Trace.ClrProfiler.Native.so"
      # if shared loader is not found, use the tracer library directly (not recommended)
      "/opt/datadog/linux-x64/Datadog.Tracer.Native.so"
      "/opt/datadog/linux-arm64/Datadog.Tracer.Native.so"
      # keep this as a fallback for backwards compatibility with older .NET layers
      "/opt/datadog/Datadog.Trace.ClrProfiler.Native.so"
    )

    PROFILER_FOUND=false

    ## Search from all possible places
    for PROFILER_PATH in "${PROFILER_PATHS[@]}"
    do
    if [ -f "$PROFILER_PATH" ]
    then
      export CORECLR_PROFILER_PATH="$PROFILER_PATH"
      PROFILER_FOUND=true
      break
    fi
    done

    if [ $PROFILER_FOUND == false ]
    then
      echo ".NET library not found. APM instrumentation may not work correctly."
    fi
  fi

  # Required environment variables for .NET library
  export CORECLR_ENABLE_PROFILING="${CORECLR_ENABLE_PROFILING:-"1"}"
  export CORECLR_PROFILER="${CORECLR_PROFILER:-"{846F5F1C-F9AE-4B07-969E-05C26BC060D8}"}"
  export DD_DOTNET_TRACER_HOME="${DD_DOTNET_TRACER_HOME:-"/opt/datadog"}"

  # Disable some .NET library features by default
  export DD_TRACE_STARTUP_LOGS="${DD_TRACE_STARTUP_LOGS:-"0"}"     # we can't completely disable all logs to disk, but we can at least disable startup logs
  export DD_CIVISIBILITY_ENABLED="${DD_CIVISIBILITY_ENABLED:-"0"}" # disable CI Visibility's auto-detect mechanism

  # log the environment variables for troubleshooting
  debug_log "CORECLR_PROFILER_PATH: $CORECLR_PROFILER_PATH"
  debug_log "CORECLR_ENABLE_PROFILING: $CORECLR_ENABLE_PROFILING"
  debug_log "CORECLR_PROFILER: $CORECLR_PROFILER"
  debug_log "DD_DOTNET_TRACER_HOME: $DD_DOTNET_TRACER_HOME"
  debug_log "DD_TRACE_STARTUP_LOGS: $DD_TRACE_STARTUP_LOGS"
  debug_log "DD_CIVISIBILITY_ENABLED: $DD_CIVISIBILITY_ENABLED"
fi # .NET

# if it is java
DD_Agent_Jar=/opt/java/lib/dd-java-agent.jar
if [[ "$AWS_EXECUTION_ENV" == *"java"* ]] && [ -f "$DD_Agent_Jar" ]
then
  debug_log "Configuring for the Java runtime!"
  export DD_JMXFETCH_ENABLED="false"
  export DD_RUNTIME_METRICS_ENABLED="false"
  export DD_REMOTE_CONFIG_ENABLED="false"
  export DD_APPSEC_ENABLED="false"

  # Removes the -XX:-TieredCompilation flag from the java command passed
  # through from the Lambda runtime. Allows the JVM to use the C1 compiler
  # and Interpreter, which is much faster on cold start and
  # uses less memory.
  START_COMMAND=${args[0]}
  REMAINDER_ARGS=("${args[@]:1}")
  for index in "${!REMAINDER_ARGS[@]}" ; do
    [[ ${REMAINDER_ARGS[$index]} == "-XX:-TieredCompilation" ]] && unset -v 'REMAINDER_ARGS[$index]' ;
  done
  REMAINDER_ARGS="${REMAINDER_ARGS[@]}"
  # -XX:TieredStopAtLevel=1 tells the compiler to stop at the C1 compiler
  args=($START_COMMAND -javaagent:$DD_Agent_Jar -XX:TieredStopAtLevel=1 ${REMAINDER_ARGS[@]})
fi

exec "${args[@]}"