Differentiate dialect and engine_type, add error handling

Author: treysp

sqlmesh/cli/example_project.py

@@ -39,12 +39,12 @@ def _gen_config(
       database: db.db"""
     )
 
+    engine = "mssql" if dialect == "tsql" else dialect
+
     if not settings and template != ProjectTemplate.DBT:
         doc_link = "https://sqlmesh.readthedocs.io/en/stable/integrations/engines{engine_link}"
         engine_link = ""
 
-        engine = "mssql" if dialect == "tsql" else dialect
-
         if engine in CONNECTION_CONFIG_TO_TYPE:
             required_fields = []
             non_required_fields = []
@@ -84,17 +84,18 @@ def _gen_config(
     default_configs = {
         ProjectTemplate.DEFAULT: f"""# --- Gateway Connection ---
 gateways:
-  {dialect}:
+  {engine}:
     connection:
 {connection_settings}
-default_gateway: {dialect}
+default_gateway: {engine}
 
 # --- Model Defaults ---
 # https://sqlmesh.readthedocs.io/en/stable/reference/model_configuration/#model-defaults
 
 model_defaults:
   dialect: {dialect}
-  start: {start or yesterday_ds()}
+  start: {start or yesterday_ds()} # Start date for backfill history
+  cron: '@daily'    # Run models daily at 12am UTC (can override per model)
 
 # --- Linting Rules ---
 # Enforce standards for your team
@@ -123,7 +124,6 @@ def _gen_config(
 # https://sqlmesh.readthedocs.io/en/stable/reference/configuration/#plan
 
 plan:
-  enable_preview: true      # Enable preview for forward-only models when targeting a development environment
   no_diff: true             # Hide detailed text differences for changed models
   use_finalized_state: true # Compare only against finalized snapshots
   no_prompts: true          # No interactive prompts
@@ -274,6 +274,7 @@ def _gen_example_objects(schema_name: str) -> ExampleObjects:
 def init_example_project(
     path: t.Union[str, Path],
     dialect: t.Optional[str],
+    engine_type: t.Optional[str],
     template: ProjectTemplate = ProjectTemplate.DEFAULT,
     pipeline: t.Optional[str] = None,
     dlt_path: t.Optional[str] = None,
@@ -294,8 +295,10 @@ def init_example_project(
             f"Found an existing config file '{config_path}'.\n\nPlease change to another directory or remove the existing file."
         )
 
-    if not dialect and template != ProjectTemplate.DBT:
-        raise SQLMeshError("Please provide a default SQL dialect for your project's models.")
+    if not engine_type and template != ProjectTemplate.DBT:
+        if not dialect:
+            raise SQLMeshError("Please provide a default SQL dialect for your project's models.")
+        Dialect.get_or_raise(dialect)
 
     models: t.Set[t.Tuple[str, str]] = set()
     settings = None
@@ -310,7 +313,11 @@ def init_example_project(
                 "Please provide a DLT pipeline with the `--dlt-pipeline` flag to generate a SQLMesh project from DLT."
             )
 
-    _create_config(config_path, dialect, settings, start, template, cli_mode)
+    # config generation chooses engine based on ConnectionConfig.type_
+    # - if user passes a SQL dialect, we always generate the engine whose type_ == dialect
+    #   - example: if users passes `postgres` we will always choose `postgres` engine and never `gcp_postgres`
+    # - if user interactively chooses an engine, we will pass the correct ConnectionConfig.type_
+    _create_config(config_path, engine_type or dialect, settings, start, template, cli_mode)
     if template == ProjectTemplate.DBT:
         return config_path
 
@@ -340,16 +347,13 @@ def _create_folders(target_folders: t.Sequence[Path]) -> None:
 
 def _create_config(
     config_path: Path,
-    dialect: t.Optional[str],
+    engine_type: t.Optional[str],
     settings: t.Optional[str],
     start: t.Optional[str],
     template: ProjectTemplate,
     cli_mode: InitCliMode,
 ) -> None:
-    if dialect:
-        Dialect.get_or_raise(dialect)
-
-    project_config = _gen_config(dialect, settings, start, template, cli_mode)
+    project_config = _gen_config(engine_type, settings, start, template, cli_mode)
 
     _write_file(
         config_path,

sqlmesh/cli/main.py

@@ -15,6 +15,7 @@
 from sqlmesh.core.console import configure_console, get_console
 from sqlmesh.utils import Verbosity
 from sqlmesh.core.config import load_configs
+from sqlmesh.core.config.connection import CONNECTION_CONFIG_TO_TYPE
 from sqlmesh.core.context import Context
 from sqlmesh.utils.date import TimeLike
 from sqlmesh.utils.errors import MissingDependencyError, SQLMeshError
@@ -39,23 +40,24 @@
 )
 SKIP_CONTEXT_COMMANDS = ("init", "ui")
 
-ENGINE_DISPLAY_NAME_TO_DIALECT = {
-    "Athena": "athena",
-    "Azure SQL": "tsql",
-    "BigQuery": "bigquery",
-    "ClickHouse": "clickhouse",
-    "Databricks": "databricks",
+# These are ordered for user display - do not reorder
+ENGINE_DISPLAY_NAME_TO_CONNECTION_TYPE = {
     "DuckDB": "duckdb",
-    "GCP Postgres": "postgres",
+    "Snowflake": "snowflake",
+    "Databricks": "databricks",
+    "BigQuery": "bigquery",
     "MotherDuck": "duckdb",
-    "MSSQL": "tsql",
-    "MySQL": "mysql",
-    "Postgres": "postgres",
+    "ClickHouse": "clickhouse",
     "Redshift": "redshift",
-    "RisingWave": "postgres",
-    "Snowflake": "snowflake",
     "Spark": "spark",
     "Trino": "trino",
+    "Azure SQL": "azuresql",
+    "MSSQL": "tsql",
+    "Postgres": "postgres",
+    "GCP Postgres": "gcp_postgres",
+    "MySQL": "mysql",
+    "Athena": "athena",
+    "RisingWave": "risingwave",
 }
 
 
@@ -201,38 +203,55 @@ def init(
 
     if sql_dialect or project_template == ProjectTemplate.DBT:
         init_example_project(
-            ctx.obj,
+            path=ctx.obj,
             dialect=sql_dialect,
+            engine_type=None,
             template=project_template or ProjectTemplate.DEFAULT,
             pipeline=dlt_pipeline,
             dlt_path=dlt_path,
         )
-    else:
-        import sqlmesh.utils.rich as srich
+        return
 
-        console = srich.console
+    import sqlmesh.utils.rich as srich
 
-        project_template, sql_dialect, cli_mode = _interactive_init(console, project_template)
-        config_path = init_example_project(
-            ctx.obj,
-            template=project_template,
-            dialect=sql_dialect,
-            cli_mode=cli_mode,
-            pipeline=dlt_pipeline,
-            dlt_path=dlt_path,
-        )
-        console.print(f"""──────────────────────────────
+    console = srich.console
+
+    project_template, engine_type, cli_mode = _interactive_init(console, project_template)
+    if project_template != ProjectTemplate.DBT:
+        _check_engine_installed(console, engine_type)
+
+    config_path = init_example_project(
+        path=ctx.obj,
+        dialect=None,
+        template=project_template,
+        engine_type=engine_type,
+        cli_mode=cli_mode or InitCliMode.DEFAULT,
+        pipeline=dlt_pipeline,
+        dlt_path=dlt_path,
+    )
+
+    next_step_text = {
+        ProjectTemplate.DEFAULT: f"• Update your gateway connection settings (e.g., username/password) in the project configuration file:\n    {config_path}\nRun command in CLI: sqlmesh plan\n(Optional) Explain a plan: sqlmesh plan --explain",
+        ProjectTemplate.DBT: "",
+    }
+    next_step_text[ProjectTemplate.EMPTY] = next_step_text[ProjectTemplate.DEFAULT]
+
+    quickstart_text = {
+        ProjectTemplate.DEFAULT: "Quickstart guide:\nhttps://sqlmesh.readthedocs.io/en/stable/quickstart/cli/",
+        ProjectTemplate.DBT: "dbt guide:\nhttps://sqlmesh.readthedocs.io/en/stable/integrations/dbt/",
+    }
+    quickstart_text[ProjectTemplate.EMPTY] = quickstart_text[ProjectTemplate.DEFAULT]
+
+    console.print(f"""──────────────────────────────
 
 Your SQLMesh project is ready!
 
 Next steps:
-• Update your gateway connection settings (e.g., username/password) in the project configuration file:
-    {config_path}
+{next_step_text[project_template]}
 • Run command in CLI: sqlmesh plan
 • (Optional) Explain a plan: sqlmesh plan --explain
 
-Quickstart guide:
-  https://sqlmesh.readthedocs.io/en/stable/quickstart/cli/
+{quickstart_text[project_template]}
 
 Need help?
 • Docs:   https://sqlmesh.readthedocs.io
@@ -1286,21 +1305,29 @@ def state_import(obj: Context, input_file: Path, replace: bool, no_confirm: bool
 
 def _interactive_init(
     console: Console, project_template: t.Optional[ProjectTemplate] = None
-) -> t.Tuple[ProjectTemplate, str, InitCliMode]:
+) -> t.Tuple[ProjectTemplate, t.Optional[str], t.Optional[InitCliMode]]:
     console.print("──────────────────────────────")
     console.print("Welcome to SQLMesh!")
 
     project_template = _init_template_prompt(console) if not project_template else project_template
-    dialect = _init_engine_prompt(console)
+
+    if project_template == ProjectTemplate.DBT:
+        if not Path("dbt_project.yml").exists():
+            raise SQLMeshError(
+                "Required file 'dbt_project.yml' not found in the current directory.\n\n Please add it or change directories before running `sqlmesh init` to set up your dbt project with SQLMesh."
+            )
+        return (project_template, None, None)
+
+    engine_type = _init_engine_prompt(console)
     cli_mode = _init_cli_mode_prompt(console)
 
-    return (project_template, dialect, cli_mode)
+    return (project_template, engine_type, cli_mode)
 
 
 def _init_integer_prompt(
     console: Console, err_msg_entity: str, num_options: int, retry_func: t.Callable[[t.Any], t.Any]
 ) -> int:
-    err_msg = "\nERROR: '{option_str}' is not a valid {err_msg_entity} number - please enter a number between 1 and {num_options} or exit with Ctrl+C"
+    err_msg = "\nERROR: '{option_str}' is not a valid {err_msg_entity} number - please enter a number between 1 and {num_options} or exit with control+c"
     option_str = Prompt.ask("Enter a number", console=console)
     try:
         option_num = int(option_str)
@@ -1321,11 +1348,11 @@ def _init_integer_prompt(
 
 
 def _init_template_prompt(console: Console) -> ProjectTemplate:
+    # These are ordered for user display - do not reorder
     template_descriptions = {
         ProjectTemplate.DEFAULT.name: "- Create SQLMesh example project models and files",
-        ProjectTemplate.EMPTY.name: "  - Create a configuration file and project file directories",
         ProjectTemplate.DBT.value: "    - You have an existing dbt project and want to run it with SQLMesh",
-        ProjectTemplate.DLT.name: "    - You have an existing DLT pipeline and want to load it with SQLMesh",
+        ProjectTemplate.EMPTY.name: "  - Create a SQLMesh configuration file and project directories only",
     }
 
     console.print("──────────────────────────────\n")
@@ -1349,7 +1376,7 @@ def _init_engine_prompt(console: Console) -> str:
     console.print("Choose your SQL engine:\n")
 
     display_num_to_engine = {}
-    for i, engine in enumerate(ENGINE_DISPLAY_NAME_TO_DIALECT.keys()):
+    for i, engine in enumerate(ENGINE_DISPLAY_NAME_TO_CONNECTION_TYPE.keys()):
         console.print(f"    \\[{i + 1}] {' ' if i < 9 else ''}{engine}")
         display_num_to_engine[i + 1] = engine
     console.print("")
@@ -1361,10 +1388,10 @@ def _init_engine_prompt(console: Console) -> str:
     # """)
 
     engine_num = _init_integer_prompt(
-        console, "engine", len(ENGINE_DISPLAY_NAME_TO_DIALECT), _init_engine_prompt
+        console, "engine", len(ENGINE_DISPLAY_NAME_TO_CONNECTION_TYPE), _init_engine_prompt
     )
 
-    return ENGINE_DISPLAY_NAME_TO_DIALECT[display_num_to_engine[engine_num]]
+    return ENGINE_DISPLAY_NAME_TO_CONNECTION_TYPE[display_num_to_engine[engine_num]]
 
 
 def _init_cli_mode_prompt(console: Console) -> InitCliMode:
@@ -1387,3 +1414,17 @@ def _init_cli_mode_prompt(console: Console) -> InitCliMode:
     )
 
     return InitCliMode(display_num_to_cli_mode[cli_mode_num].lower())
+
+
+def _check_engine_installed(console: Console, engine_type: t.Optional[str] = None) -> None:
+    if not engine_type:
+        return
+    connection_config = CONNECTION_CONFIG_TO_TYPE[engine_type]
+
+    try:
+        connection_config._connection_factory.fget(None)
+    except ModuleNotFoundError:
+        install_command = f'pip install "sqlmesh[{engine_type}]"'
+        raise SQLMeshError(
+            f"Unable to load required Python dependencies for the {engine_type.upper()} engine.\n\nPlease run `{install_command}` to install them before running `sqlmesh init` again."
+        )

sqlmesh/magics.py

@@ -190,7 +190,12 @@ def init(self, line: str) -> None:
         except ValueError:
             raise MagicError(f"Invalid project template '{args.template}'")
         init_example_project(
-            args.path, args.sql_dialect, project_template, args.dlt_pipeline, args.dlt_path
+            path=args.path,
+            dialect=args.sql_dialect,
+            engine_type=None,
+            template=project_template,
+            pipeline=args.dlt_pipeline,
+            dlt_path=args.dlt_path,
         )
         html = str(
             h(