feat(installer): add error handling for json/yaml parsing operations

dream-server/installers/lib/json-utils.sh

@@ -0,0 +1,160 @@
+#!/bin/bash
+# ============================================================================
+# Dream Server Installer — JSON/YAML Utilities
+# ============================================================================
+# Part of: installers/lib/
+# Purpose: Safe JSON/YAML parsing with error handling
+#
+# Expects: (nothing — can be sourced independently)
+# Provides: safe_json_parse(), safe_yaml_parse(), validate_json_file()
+#
+# Modder notes:
+#   Add new parsing utilities here.
+# ============================================================================
+
+# Safely parse JSON with error handling
+# Usage: safe_json_parse <json_string> [jq_filter]
+# Returns: 0 on success, 1 on parse error
+safe_json_parse() {
+    local json_string="$1"
+    local jq_filter="${2:-.}"
+
+    if [[ -z "$json_string" ]]; then
+        echo "ERROR: Empty JSON string" >&2
+        return 1
+    fi
+
+    # Try to parse with jq
+    if command -v jq &>/dev/null; then
+        echo "$json_string" | jq -e "$jq_filter" 2>/dev/null
+        return $?
+    fi
+
+    # Fallback to Python
+    python3 - "$json_string" "$jq_filter" <<'PY' 2>/dev/null
+import json
+import sys
+
+try:
+    data = json.loads(sys.argv[1])
+    filter_expr = sys.argv[2]
+
+    # Simple filter support (just key access for now)
+    if filter_expr != ".":
+        keys = filter_expr.strip(".").split(".")
+        for key in keys:
+            if key:
+                data = data.get(key, None)
+                if data is None:
+                    sys.exit(1)
+
+    print(json.dumps(data) if isinstance(data, (dict, list)) else data)
+    sys.exit(0)
+except (json.JSONDecodeError, KeyError, TypeError) as e:
+    print(f"JSON parse error: {e}", file=sys.stderr)
+    sys.exit(1)
+PY
+}
+
+# Validate a JSON file
+# Usage: validate_json_file <file_path>
+# Returns: 0 if valid, 1 if invalid
+validate_json_file() {
+    local file_path="$1"
+
+    if [[ ! -f "$file_path" ]]; then
+        echo "ERROR: File not found: $file_path" >&2
+        return 1
+    fi
+
+    if command -v jq &>/dev/null; then
+        jq empty "$file_path" 2>/dev/null
+        return $?
+    fi
+
+    # Fallback to Python
+    python3 - "$file_path" <<'PY' 2>/dev/null
+import json
+import sys
+from pathlib import Path
+
+try:
+    data = json.loads(Path(sys.argv[1]).read_text())
+    sys.exit(0)
+except (json.JSONDecodeError, FileNotFoundError) as e:
+    print(f"JSON validation error: {e}", file=sys.stderr)
+    sys.exit(1)
+PY
+}
+
+# Safely parse YAML with error handling
+# Usage: safe_yaml_parse <yaml_file>
+# Returns: 0 on success, 1 on parse error
+safe_yaml_parse() {
+    local yaml_file="$1"
+
+    if [[ ! -f "$yaml_file" ]]; then
+        echo "ERROR: File not found: $yaml_file" >&2
+        return 1
+    fi
+
+    python3 - "$yaml_file" <<'PY' 2>/dev/null
+import sys
+from pathlib import Path
+
+try:
+    import yaml
+    data = yaml.safe_load(Path(sys.argv[1]).read_text())
+    import json
+    print(json.dumps(data))
+    sys.exit(0)
+except ImportError:
+    print("ERROR: PyYAML not available", file=sys.stderr)
+    sys.exit(1)
+except yaml.YAMLError as e:
+    print(f"YAML parse error: {e}", file=sys.stderr)
+    sys.exit(1)
+except Exception as e:
+    print(f"Error: {e}", file=sys.stderr)
+    sys.exit(1)
+PY
+}
+
+# Get a value from JSON file with error handling
+# Usage: json_get <file_path> <key_path>
+# Example: json_get config.json ".database.host"
+json_get() {
+    local file_path="$1"
+    local key_path="$2"
+
+    if [[ ! -f "$file_path" ]]; then
+        echo "ERROR: File not found: $file_path" >&2
+        return 1
+    fi
+
+    if command -v jq &>/dev/null; then
+        jq -r "$key_path" "$file_path" 2>/dev/null || return 1
+    else
+        python3 - "$file_path" "$key_path" <<'PY' 2>/dev/null
+import json
+import sys
+from pathlib import Path
+
+try:
+    data = json.loads(Path(sys.argv[1]).read_text())
+    keys = sys.argv[2].strip(".").split(".")
+
+    for key in keys:
+        if key:
+            data = data.get(key, None)
+            if data is None:
+                sys.exit(1)
+
+    print(data)
+    sys.exit(0)
+except Exception as e:
+    print(f"Error: {e}", file=sys.stderr)
+    sys.exit(1)
+PY
+    fi
+}

dream-server/scripts/load-backend-contract.sh

@@ -39,7 +39,18 @@ if [[ "$ENV_MODE" == "true" ]]; then
 import json
 import sys
 
-contract = json.load(open(sys.argv[1], "r", encoding="utf-8"))
+try:
+    with open(sys.argv[1], "r", encoding="utf-8") as f:
+        contract = json.load(f)
+except json.JSONDecodeError as e:
+    print(f"ERROR: Invalid JSON in backend contract: {e}", file=sys.stderr)
+    sys.exit(1)
+except FileNotFoundError:
+    print(f"ERROR: Backend contract file not found: {sys.argv[1]}", file=sys.stderr)
+    sys.exit(1)
+except Exception as e:
+    print(f"ERROR: Failed to load backend contract: {e}", file=sys.stderr)
+    sys.exit(1)
 
 def out(key, value):
     safe = str(value).replace("\\", "\\\\").replace('"', '\\"')