add Var functor to allow for arbitrary configs

dbt/compilation.py

@@ -5,7 +5,7 @@
 from collections import defaultdict
 import dbt.project
 from dbt.source import Source
-from dbt.utils import find_model_by_fqn, find_model_by_name, dependency_projects, split_path, This
+from dbt.utils import find_model_by_fqn, find_model_by_name, dependency_projects, split_path, This, Var
 from dbt.linker import Linker
 import time
 import sqlparse
@@ -136,6 +136,7 @@ def compile_model(self, linker, model, models):
         context['ref'] = self.__ref(linker, context, model, models)
         context['config'] = self.__model_config(model, linker)
         context['this'] = This(context['env']['schema'], model.immediate_name, model.name)
+        context['var'] = Var(model)
         context['compiled_at'] = time.strftime('%Y-%m-%d %H:%M:%S')
 
         hook_keys = ['pre-hook', 'post-hook']

dbt/model.py

@@ -7,11 +7,11 @@
 from dbt.utils import split_path
 import dbt.schema_tester
 import dbt.project
-from dbt.utils import This
+from dbt.utils import This, DBTConfigKeys
 
 class SourceConfig(object):
     Materializations = ['view', 'table', 'incremental', 'ephemeral']
-    ConfigKeys = ['enabled', 'materialized', 'dist', 'sort', 'sql_where', 'unique_key', 'sort_type', 'pre-hook', 'post-hook']
+    ConfigKeys = DBTConfigKeys
 
     def __init__(self, active_project, own_project, fqn):
         self.active_project = active_project
@@ -201,6 +201,9 @@ def rename_query(self, schema):
 
         return 'alter table "{schema}"."{tmp_name}" rename to "{final_name}"'.format(**opts)
 
+    @property
+    def nice_name(self):
+        return "{}.{}".format(self.fqn[0], self.fqn[-1])
 
 class Model(DBTSource):
     dbt_run_type = 'run'

dbt/utils.py

@@ -1,6 +1,21 @@
 
 import os
 import dbt.project
+import pprint
+import json
+
+DBTConfigKeys = [
+    'enabled',
+    'materialized',
+    'dist',
+    'sort',
+    'sql_where',
+    'unique_key',
+    'sort_type',
+    'pre-hook',
+    'post-hook',
+    'vars'
+]
 
 class This(object):
     def __init__(self, schema, table, name=None):
@@ -14,6 +29,28 @@ def schema_table(self, schema, table):
     def __repr__(self):
         return self.schema_table(self.schema, self.table)
 
+class Var(object):
+    UndefinedVarError = "Required var '{}' not found in config:\nVars supplied to {} = {}"
+
+    def __init__(self, model):
+        self.model = model
+        self.local_vars = model.config.get('vars', {})
+
+    def compiler_error(self, model, msg):
+        raise RuntimeError("Compilation error while compiling model {}\n{}".format(model.nice_name, msg))
+
+    def pretty_dict(self, data):
+        return json.dumps(data, sort_keys=True, indent=4)
+
+    def __call__(self, var_name, default=None):
+        if var_name not in self.local_vars and default is None:
+            pretty_vars = self.pretty_dict(self.local_vars)
+            self.compiler_error(self.model, self.UndefinedVarError.format(var_name, self.model.nice_name, pretty_vars))
+        elif var_name in self.local_vars:
+            return self.local_vars[var_name]
+        else:
+            return default
+
 def find_model_by_name(models, name, package_namespace=None):
     found = []
     for model in models: