Automatically generate examples documentation (#19294)

ci/scripts/generate_examples_docs.sh

@@ -0,0 +1,112 @@
+#!/usr/bin/env bash
+#
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+
+set -euo pipefail
+
+EXAMPLES_DIR="datafusion-examples/examples"
+SKIP_LIST=("ffi")
+ONLY_GROUP=""
+
+# ------------------------
+# Argument parsing
+# ------------------------
+while [[ $# -gt 0 ]]; do
+  case "$1" in
+    --group)
+      ONLY_GROUP="${2:-}"
+      if [[ -z "$ONLY_GROUP" ]]; then
+        echo "Error: --group requires a value"
+        exit 1
+      fi
+      shift 2
+      ;;
+    *)
+      echo "Unknown argument: $1"
+      echo "Usage: $0 [--group <group_name>]"
+      exit 1
+      ;;
+  esac
+done
+
+# ------------------------
+# Helpers
+# ------------------------
+title_case() {
+  # custom_data_source -> Custom Data Source
+  echo "$1" \
+    | tr '_' ' ' \
+    | awk '{ for (i=1; i<=NF; i++) { $i = toupper(substr($i,1,1)) substr($i,2) } print }'
+}
+
+skip() {
+  local value="$1"
+  for item in "${SKIP_LIST[@]}"; do
+    [[ "$item" == "$value" ]] && return 0
+  done
+  return 1
+}
+
+generate_group_docs() {
+  local group="$1"
+
+  group_title="$(title_case "$group") Examples"
+
+  echo "## ${group_title}"
+  echo
+  echo "### Group: \`${group}\`"
+  echo
+  echo "#### Category: Single Process"
+  echo
+  echo "| Subcommand | File Path | Description |"
+  echo "| ---------- | --------- | ----------- |"
+
+  for file in $(find "$EXAMPLES_DIR/$group" -maxdepth 1 -name "*.rs" -exec basename {} \; | sort); do
+    [[ "$file" == "main.rs" ]] && continue
+
+    subcommand="${file%.rs}"
+    path="examples/${group}/${file}"
+
+    echo "| ${subcommand} | [\`${group}/${file}\`](${path}) | TODO |"
+  done
+
+  echo
+}
+
+# ------------------------
+# Main logic
+# ------------------------
+if [[ -n "$ONLY_GROUP" ]]; then
+  if [[ ! -d "$EXAMPLES_DIR/$ONLY_GROUP" ]]; then
+    echo "Error: group '$ONLY_GROUP' does not exist in $EXAMPLES_DIR"
+    exit 1
+  fi
+
+  if skip "$ONLY_GROUP"; then
+    echo "Group '$ONLY_GROUP' is skipped"
+    exit 0
+  fi
+
+  generate_group_docs "$ONLY_GROUP"
+else
+  for group in $(find "$EXAMPLES_DIR" -mindepth 1 -maxdepth 1 -type d -exec basename {} \; | sort); do
+    skip "$group" && continue
+    generate_group_docs "$group"
+  done
+fi
+