1 files changed, 32 insertions, 0 deletions
diff --git a/tools/cru-py/crupest/template.py b/tools/cru-py/crupest/template.py
new file mode 100644
index 0000000..9747af1
--- /dev/null
+++ b/tools/cru-py/crupest/template.py
@@ -0,0 +1,32 @@
+import os.path
+import re
+
+
+class Template:
+    def __init__(self, template_path: str, var_prefix: str = "CRUPEST"):
+        if len(var_prefix) != 0 and re.fullmatch(r"^[a-zA-Z_][a-zA-Z0-9_]*$", var_prefix) is None:
+            raise ValueError("Invalid var prefix.")
+        self.template_path = template_path
+        self.template_name = os.path.basename(
+            template_path)[:-len(".template")]
+        with open(template_path, "r") as f:
+            self.template = f.read()
+        self.var_prefix = var_prefix
+        self.__var_regex = re.compile(r"\$(" + var_prefix + r"_[a-zA-Z0-9_]+)")
+        self.__var_brace_regex = re.compile(
+            r"\$\{\s*(" + var_prefix + r"_[a-zA-Z0-9_]+)\s*\}")
+        var_set = set()
+        for match in self.__var_regex.finditer(self.template):
+            var_set.add(match.group(1))
+        for match in self.__var_brace_regex.finditer(self.template):
+            var_set.add(match.group(1))
+        self.var_set = var_set
+
+    def generate(self, config: dict) -> str:
+        result = self.template
+        for var in self.var_set:
+            if var not in config:
+                raise ValueError(f"Missing config var {var}.")
+            result = result.replace("$" + var, config[var])
+            result = re.sub(r"\$\{\s*" + var + r"\s*\}", config[var], result)
+        return result