chore!: add supported configurations

.github/workflows/dev.yml

@@ -2,7 +2,7 @@ name: "Development"
 on: [pull_request, workflow_dispatch, workflow_call]
 
 jobs:
-  format:
+  format-and-verify-configurations:
     runs-on: ubuntu-22.04-arm
     container:
       image: datadog/docker-library:dd-trace-cpp-ci-23768e9-arm64
@@ -12,6 +12,19 @@ jobs:
         run: bin/check-format
       - name: Shellcheck
         run: find bin/ -executable -type f -print0 | xargs -0 shellcheck
+      - name: Verify environment variable allowlist
+        run: bin/check-environment-variables
+      - name: Verify supported configurations metadata
+        run: |
+          tmp_dir="$(mktemp -d)"
+          trap 'rm -rf "$tmp_dir"' EXIT
+          cp metadata/supported-configurations.json "$tmp_dir/supported-configurations.json"
+          bin/generate-supported-configurations
+          if ! diff -q "$tmp_dir/supported-configurations.json" metadata/supported-configurations.json >/dev/null 2>&1; then
+            echo "ERROR: metadata/supported-configurations.json got out of sync with implemented configurations. Please run bin/generate-supported-configurations locally."
+            diff -u "$tmp_dir/supported-configurations.json" metadata/supported-configurations.json || true
+            exit 1
+          fi
 
   build-linux-cmake:
     strategy:
@@ -26,7 +39,7 @@ jobs:
           - runner: ubuntu-22.04
             arch: x64
             docker-arch: amd64
-    needs: format
+    needs: format-and-verify-configurations
     runs-on: ${{ matrix.runner }}
     container:
       image: datadog/docker-library:dd-trace-cpp-ci-23768e9-${{matrix.docker-arch}}
@@ -54,7 +67,7 @@ jobs:
           datadog-ci junit upload --service dd-trace-cpp --tags test.source.file:test/*.cpp .build/report.xml
 
   build-linux-bazel:
-    needs: format
+    needs: format-and-verify-configurations
     strategy:
       fail-fast: false
       matrix:
@@ -77,7 +90,7 @@ jobs:
         run: bin/with-toolchain ${{ matrix.toolchain }} bazelisk --bazelrc=${{ matrix.bazelrc }} build dd_trace_cpp
 
   build-windows-bazel:
-    needs: format
+    needs: format-and-verify-configurations
     runs-on: windows-2022
     defaults:
       run:
@@ -98,7 +111,7 @@ jobs:
         run: bazelisk.exe --bazelrc=${{ matrix.bazelrc }} build dd_trace_cpp
 
   build-windows-cmake:
-    needs: format
+    needs: format-and-verify-configurations
     strategy:
       fail-fast: false
       matrix:

.gitignore

@@ -11,4 +11,5 @@ MODULE.bazel.lock
 .vscode
 .cache/
 .cursor/
-.DS_Store
+.DS_Store
+bin/.supported-configurations

.gitlab-ci.yml

@@ -1,5 +1,34 @@
 stages:
+  - shared-pipeline
   - benchmarks
   - benchmarks-report
 
-include: ".gitlab/benchmarks.yml"
+variables:
+  SKIP_SHARED_PIPELINE: "true"
+
+workflow:
+  auto_cancel:
+    on_new_commit: interruptible
+  rules:
+    - if: $CI_COMMIT_TAG =~ /^v?[0-9]+\.[0-9]+\.[0-9]+$/
+      variables:
+        DANGEROUSLY_SKIP_SHARED_PIPELINE_TESTS: "true"
+    - when: always
+
+validate_supported_configurations_v2_local_file:
+  extends: .validate_supported_configurations_v2_local_file
+  variables:
+    LOCAL_JSON_PATH: "metadata/supported-configurations.json"
+    BACKFILLED: "false"
+
+update_central_configurations_version_range_v2:
+  extends: .update_central_configurations_version_range_v2
+  variables:
+    LOCAL_REPO_NAME: "dd-trace-cpp"
+    LOCAL_JSON_PATH: "metadata/supported-configurations.json"
+    LANGUAGE_NAME: "cpp"
+    MULTIPLE_RELEASE_LINES: "false"
+
+include:
+  - local: ".gitlab/one-pipeline.locked.yml"
+  - local: ".gitlab/benchmarks.yml"

.gitlab/one-pipeline.locked.yml

@@ -0,0 +1,3 @@
+# This file should be auto-generated soon.
+include:
+  - remote: https://gitlab-templates.ddbuild.io/libdatadog/one-pipeline/ca/fbfa24e9dd887ed24ce65e71f2e41562c809f40cfc26489705b32406de7e096f/one-pipeline.yml

BUILD.bazel

@@ -109,6 +109,7 @@ cc_library(
         "include/datadog/dict_reader.h",
         "include/datadog/dict_writer.h",
         "include/datadog/environment.h",
+        "include/datadog/environment_registry.h",
         "include/datadog/error.h",
         "include/datadog/event_scheduler.h",
         "include/datadog/expected.h",

bin/README.md

@@ -1,5 +1,6 @@
 Scripts
 =======
+
 This directory contains scripts that are useful during development.
 
 - [bazel-build](bazel-build) builds the library using [Bazel][1] via [bazelisk][2].
@@ -8,6 +9,12 @@ This directory contains scripts that are useful during development.
 - [check](check) performs some of the checks that [continuous
   integration](../.circleci) performs. It's convenient to run this script before
   pushing changes.
+- [check-environment-variables](check-environment-variables) validates that
+  all `DD_`/`OTEL_` environment variables used by the codebase are allowlisted
+  in
+  [include/datadog/environment_registry.h](../include/datadog/environment_registry.h)
+  (the source of truth used by
+  [include/datadog/environment.h](../include/datadog/environment.h)).
 - [check-format](check-format) verifies that the source code is formatted as
   [format](format) prefers.
 - [check-version](check-version) accepts a version string as a command line
@@ -16,6 +23,21 @@ This directory contains scripts that are useful during development.
 - [cmake-build](cmake-build) builds the library using [CMake][3].
 - [format](format) formats all of the C++ source code using
   [clang-format-14][4].
+- [generate-supported-configurations](generate-supported-configurations)
+  regenerates
+  [metadata/supported-configurations.json](../metadata/supported-configurations.json)
+  using
+  [include/datadog/environment_registry.h](../include/datadog/environment_registry.h)
+  as the source of truth.
+  To add a new supported environment variable:
+  1. update
+     [include/datadog/environment_registry.h](../include/datadog/environment_registry.h),
+  2. run [generate-supported-configurations](generate-supported-configurations),
+  3. run [check-environment-variables](check-environment-variables).
+  This script (and [check-environment-variables](check-environment-variables))
+  compiles and executes
+  [supported-configurations.cpp](supported-configurations.cpp) via
+  [supported-configurations](supported-configurations).
 - [hasher-example](hasher-example) builds the library, including the [command
   line example](../examples/hasher) program, and then runs the example.
 - [http-server-example](http-server-example) runs the docker compose based [HTTP

bin/check-environment-variables

@@ -0,0 +1,6 @@
+#!/bin/sh
+
+set -eu
+
+SCRIPT_DIR=$(cd "$(dirname "$0")" && pwd)
+exec "$SCRIPT_DIR/supported-configurations" check

bin/generate-supported-configurations

@@ -0,0 +1,6 @@
+#!/bin/sh
+
+set -eu
+
+SCRIPT_DIR=$(cd "$(dirname "$0")" && pwd)
+exec "$SCRIPT_DIR/supported-configurations" generate

bin/supported-configurations

@@ -0,0 +1,19 @@
+#!/bin/sh
+
+set -eu
+
+SCRIPT_DIR=$(cd "$(dirname "$0")" && pwd)
+REPO_ROOT=$(cd "$SCRIPT_DIR/.." && pwd)
+SOURCE="$SCRIPT_DIR/supported-configurations.cpp"
+BINARY="$SCRIPT_DIR/.supported-configurations"
+
+compiler=${CXX:-c++}
+
+(
+  # `CXX` may contain wrappers/flags (e.g. "ccache c++").
+  # shellcheck disable=SC2086
+  set -- $compiler
+  "$@" -std=c++17 -O2 -I"$REPO_ROOT/src/datadog" "$SOURCE" -o "$BINARY"
+)
+
+exec "$BINARY" "$@"