Add logic for recognizing jinja code in models

setup.py

@@ -27,6 +27,7 @@
         "duckdb",
         "dateparser",
         "hyperscript",
+        "jinja2",
         "pandas",
         "pydantic",
         "requests",

sqlmesh/core/context.py

@@ -49,7 +49,7 @@
 from sqlmesh.core.console import Console, get_console
 from sqlmesh.core.context_diff import ContextDiff
 from sqlmesh.core.dag import DAG
-from sqlmesh.core.dialect import extend_sqlglot, format_model_expressions
+from sqlmesh.core.dialect import JinjaModel, extend_sqlglot, format_model_expressions
 from sqlmesh.core.engine_adapter import EngineAdapter
 from sqlmesh.core.environment import Environment
 from sqlmesh.core.macros import macro
@@ -65,6 +65,7 @@
 from sqlmesh.utils.date import TimeLike, yesterday_ds
 from sqlmesh.utils.errors import ConfigError, MissingDependencyError, PlanError
 from sqlmesh.utils.file_cache import FileCache
+from sqlmesh.utils.jinja import JINJA_RE
 
 if t.TYPE_CHECKING:
     import graphviz
@@ -657,7 +658,13 @@ def _load_models(self):
         for path in self._glob_path(self.models_directory_path, ".sql"):
             self._path_mtimes[path] = path.stat().st_mtime
             with open(path, "r", encoding="utf-8") as file:
-                expressions = parse(file.read(), read=self.dialect)
+                file_contents = file.read()
+
+                if JINJA_RE.search(file_contents):
+                    expressions = [JinjaModel(this=file_contents)]
+                else:
+                    expressions = parse(file_contents, read=self.dialect)
+
                 model = Model.load(
                     expressions,
                     module=module,

sqlmesh/core/dialect.py

@@ -9,6 +9,10 @@ class Model(exp.Expression):
     arg_types = {"expressions": True}
 
 
+class JinjaModel(exp.Expression):
+    """Stores a model file that contains Jinja code as a raw string."""
+
+
 class Audit(exp.Expression):
     arg_types = {"expressions": True}
 

sqlmesh/core/model.py

@@ -609,7 +609,7 @@ class Model(ModelMeta, frozen=True):
         python_env: Dictionary containing all global variables needed to render the model's macros.
     """
 
-    query: t.Union[exp.Subqueryable, d.MacroVar]
+    query: t.Union[exp.Subqueryable, d.MacroVar, d.JinjaModel]
     expressions_: t.Optional[t.List[exp.Expression]] = Field(
         default=None, alias="expressions"
     )
@@ -664,6 +664,15 @@ def load(
             time_column_format: The default time column format to use if no model time column is configured.
         """
         if len(expressions) < 2:
+            if expressions and isinstance(expressions[0], d.JinjaModel):
+                model = cls(
+                    query=expressions[0], name="test"
+                )  # We need the model's name for this instantiation to be valid
+                model._path = path
+
+                model.validate_definition()
+                return model
+
             _raise_config_error(
                 "Incomplete model definition, missing MODEL and QUERY", path
             )
@@ -953,6 +962,11 @@ def render_query(
         Returns:
             The rendered expression.
         """
+
+        # If the query is an instance of d.JinjaModel, render it and parse the produced string
+        # to create and validate the resulting model. Then we can extract the query and pass it
+        # as the query_ argument below. Do we want to do any validation earlier (e.g. inside load())?
+
         return self._render_query(
             start=start,
             end=end,

sqlmesh/utils/jinja.py

@@ -0,0 +1,5 @@
+import re
+
+# Captures one of the following patterns: "{{", "{#", "{%" and "{%-".
+# Q: this will also flag text that contains "{{" inside a string as Jinja. Is this a problem?
+JINJA_RE = re.compile("{({|#|(%(-)?))")