Source code for superset.jinja_context

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# pylint: disable=C,R,W
"""Defines the templating context for SQL Lab"""
from datetime import datetime, timedelta
import inspect
import json
import random
import time
import uuid

from dateutil.relativedelta import relativedelta
from flask import g, request
from jinja2.sandbox import SandboxedEnvironment

from superset import app

config = app.config
    'datetime': datetime,
    'random': random,
    'relativedelta': relativedelta,
    'time': time,
    'timedelta': timedelta,
    'uuid': uuid,
BASE_CONTEXT.update(config.get('JINJA_CONTEXT_ADDONS', {}))

[docs]def url_param(param, default=None): """Read a url or post parameter and use it in your SQL Lab query When in SQL Lab, it's possible to add arbitrary URL "query string" parameters, and use those in your SQL code. For instance you can alter your url and add `?foo=bar`, as in `{domain}/superset/sqllab?foo=bar`. Then if your query is something like SELECT * FROM foo = '{{ url_param('foo') }}', it will be parsed at runtime and replaced by the value in the URL. As you create a visualization form this SQL Lab query, you can pass parameters in the explore view as well as from the dashboard, and it should carry through to your queries. :param param: the parameter to lookup :type param: str :param default: the value to return in the absence of the parameter :type default: str """ if request.args.get(param): return request.args.get(param, default) # Supporting POST as well as get if request.form.get('form_data'): form_data = json.loads(request.form.get('form_data')) url_params = form_data.get('url_params') or {} return url_params.get(param, default) return default
def current_user_id(): """The id of the user who is currently logged in""" if hasattr(g, 'user') and g.user: return def current_username(): """The username of the user who is currently logged in""" if g.user: return g.user.username
[docs]def filter_values(column, default=None): """ Gets a values for a particular filter as a list This is useful if: - you want to use a filter box to filter a query where the name of filter box column doesn't match the one in the select statement - you want to have the ability for filter inside the main query for speed purposes This searches for "filters" and "extra_filters" in form_data for a match Usage example: SELECT action, count(*) as times FROM logs WHERE action in ( {{ "'" + "','".join(filter_values('action_type')) + "'" }} ) GROUP BY 1 :param column: column/filter name to lookup :type column: str :param default: default value to return if there's no matching columns :type default: str :return: returns a list of filter values :type: list """ form_data = json.loads(request.form.get('form_data', '{}')) return_val = [] for filter_type in ['filters', 'extra_filters']: if filter_type not in form_data: continue for f in form_data[filter_type]: if f['col'] == column: for v in f['val']: return_val.append(v) if return_val: return return_val if default: return [default] else: return []
class BaseTemplateProcessor(object): """Base class for database-specific jinja context There's this bit of magic in ``process_template`` that instantiates only the database context for the active database as a ``models.Database`` object binds it to the context object, so that object methods have access to that context. This way, {{ hive.latest_partition('mytable') }} just knows about the database it is operating in. This means that object methods are only available for the active database and are given access to the ``models.Database`` object and schema name. For globally available methods use ``@classmethod``. """ engine = None def __init__(self, database=None, query=None, table=None, **kwargs): self.database = database self.query = query self.schema = None if query and query.schema: self.schema = query.schema elif table: self.schema = table.schema self.context = { 'url_param': url_param, 'current_user_id': current_user_id, 'current_username': current_username, 'filter_values': filter_values, 'form_data': {}, } self.context.update(kwargs) self.context.update(BASE_CONTEXT) if self.engine: self.context[self.engine] = self self.env = SandboxedEnvironment() def process_template(self, sql, **kwargs): """Processes a sql template >>> sql = "SELECT '{{ datetime(2017, 1, 1).isoformat() }}'" >>> process_template(sql) "SELECT '2017-01-01T00:00:00'" """ template = self.env.from_string(sql) kwargs.update(self.context) return template.render(kwargs)
[docs]class PrestoTemplateProcessor(BaseTemplateProcessor): """Presto Jinja context The methods described here are namespaced under ``presto`` in the jinja context as in ``SELECT '{{ presto.some_macro_call() }}'`` """ engine = 'presto' @staticmethod def _schema_table(table_name, schema): if '.' in table_name: schema, table_name = table_name.split('.') return table_name, schema def latest_partition(self, table_name): table_name, schema = self._schema_table(table_name, self.schema) return self.database.db_engine_spec.latest_partition( table_name, schema, self.database)[1] def latest_sub_partition(self, table_name, **kwargs): table_name, schema = self._schema_table(table_name, self.schema) return self.database.db_engine_spec.latest_sub_partition( table_name=table_name, schema=schema, database=self.database, **kwargs)
class HiveTemplateProcessor(PrestoTemplateProcessor): engine = 'hive' template_processors = {} keys = tuple(globals().keys()) for k in keys: o = globals()[k] if o and inspect.isclass(o) and issubclass(o, BaseTemplateProcessor): template_processors[o.engine] = o def get_template_processor(database, table=None, query=None, **kwargs): TP = template_processors.get(database.backend, BaseTemplateProcessor) return TP(database=database, table=table, query=query, **kwargs)