Question.js

/* @flow weak */

import Query from "./queries/Query";

import Metadata from "./metadata/Metadata";
import Table from "./metadata/Table";
import Field from "./metadata/Field";

import StructuredQuery, {
  STRUCTURED_QUERY_TEMPLATE,
} from "./queries/StructuredQuery";
import NativeQuery from "./queries/NativeQuery";

import { memoize } from "metabase-lib/lib/utils";
import * as Card_DEPRECATED from "metabase/lib/card";

import { getParametersWithExtras } from "metabase/meta/Card";

import {
  summarize,
  pivot,
  filter,
  breakout,
  toUnderlyingRecords,
  drillUnderlyingRecords,
} from "metabase/qb/lib/actions";

import _ from "underscore";
import { chain, assoc } from "icepick";

import type {
  Parameter as ParameterObject,
  ParameterValues,
} from "metabase/meta/types/Parameter";
import type {
  DatasetQuery,
  Card as CardObject,
  VisualizationSettings,
} from "metabase/meta/types/Card";

import { MetabaseApi, CardApi } from "metabase/services";
import AtomicQuery from "metabase-lib/lib/queries/AtomicQuery";

import type { Dataset } from "metabase/meta/types/Dataset";
import type { TableId } from "metabase/meta/types/Table";
import type { DatabaseId } from "metabase/meta/types/Database";
import * as Urls from "metabase/lib/urls";
import Mode from "metabase-lib/lib/Mode";
import {
  ALERT_TYPE_PROGRESS_BAR_GOAL,
  ALERT_TYPE_ROWS,
  ALERT_TYPE_TIMESERIES_GOAL,
} from "metabase-lib/lib/Alert";

/**
 * This is a wrapper around a question/card object, which may contain one or more Query objects
 */
export default class Question {
  /**
   * The Question wrapper requires a metadata object because the queries it contains (like {@link StructuredQuery))
   * need metadata for accessing databases, tables and metrics.
   */
  _metadata: Metadata;

  /**
   * The plain object presentation of this question, equal to the format that Metabase REST API understands.
   * It is called `card` for both historical reasons and to make a clear distinction to this class.
   */
  _card: CardObject;

  /**
   * Parameter values mean either the current values of dashboard filters or SQL editor template parameters.
   * They are in the grey area between UI state and question state, but having them in Question wrapper is convenient.
   */
  _parameterValues: ParameterValues;

  /**
   * Question constructor
   */
  constructor(
    metadata: Metadata,
    card: CardObject,
    parameterValues?: ParameterValues,
  ) {
    this._metadata = metadata;
    this._card = card;
    this._parameterValues = parameterValues || {};
  }

  /**
   * TODO Atte Keinänen 6/13/17: Discussed with Tom that we could use the default Question constructor instead,
   * but it would require changing the constructor signature so that `card` is an optional parameter and has a default value
   */
  static create({
    databaseId,
    tableId,
    metadata,
    parameterValues,
    ...cardProps
  }: {
    databaseId?: DatabaseId,
    tableId?: TableId,
    metadata: Metadata,
    parameterValues?: ParameterValues,
  } = {}) {
    // $FlowFixMe
    const card: Card = {
      name: cardProps.name || null,
      display: cardProps.display || "table",
      visualization_settings: cardProps.visualization_settings || {},
      dataset_query: STRUCTURED_QUERY_TEMPLATE, // temporary placeholder
    };

    const initialQuestion = new Question(metadata, card, parameterValues);
    const query = StructuredQuery.newStucturedQuery({
      question: initialQuestion,
      databaseId,
      tableId,
    });

    return initialQuestion.setQuery(query);
  }

  metadata(): Metadata {
    return this._metadata;
  }

  card() {
    return this._card;
  }
  setCard(card: CardObject): Question {
    return new Question(this._metadata, card, this._parameterValues);
  }

  withoutNameAndId() {
    return this.setCard(
      chain(this.card())
        .dissoc("id")
        .dissoc("name")
        .dissoc("description")
        .value(),
    );
  }

  /**
   * A question contains either a:
   * - StructuredQuery for queries written in MBQL
   * - NativeQuery for queries written in data source's native query language
   *
   * This is just a wrapper object, the data is stored in `this._card.dataset_query` in a format specific to the query type.
   */
  @memoize
  query(): Query {
    const datasetQuery = this._card.dataset_query;

    for (const QueryClass of [StructuredQuery, NativeQuery]) {
      if (QueryClass.isDatasetQueryType(datasetQuery)) {
        return new QueryClass(this, datasetQuery);
      }
    }

    throw new Error("Unknown query type: " + datasetQuery.type);
  }

  isNative(): boolean {
    return this.query() instanceof NativeQuery;
  }

  /**
   * Returns a new Question object with an updated query.
   * The query is saved to the `dataset_query` field of the Card object.
   */
  setQuery(newQuery: Query): Question {
    if (this._card.dataset_query !== newQuery.datasetQuery()) {
      return this.setCard(
        assoc(this.card(), "dataset_query", newQuery.datasetQuery()),
      );
    }
    return this;
  }

  setDatasetQuery(newDatasetQuery: DatasetQuery): Question {
    return this.setCard(assoc(this.card(), "dataset_query", newDatasetQuery));
  }

  /**
   * Returns a list of atomic queries (NativeQuery or StructuredQuery) contained in this question
   */
  atomicQueries(): AtomicQuery[] {
    const query = this.query();
    if (query instanceof AtomicQuery) return [query];
    return [];
  }

  /**
   * The visualization type of the question
   */
  display(): string {
    return this._card && this._card.display;
  }
  setDisplay(display) {
    return this.setCard(assoc(this.card(), "display", display));
  }

  visualizationSettings(): VisualizationSettings {
    return this._card && this._card.visualization_settings;
  }
  setVisualizationSettings(settings: VisualizationSettings) {
    return this.setCard(assoc(this.card(), "visualization_settings", settings));
  }

  isEmpty(): boolean {
    return this.query().isEmpty();
  }
  /**
   * Question is valid (as far as we know) and can be executed
   */
  canRun(): boolean {
    return this.query().canRun();
  }

  canWrite(): boolean {
    return this._card && this._card.can_write;
  }

  /**
   * Returns the type of alert that current question supports
   *
   * The `visualization_settings` in card object doesn't contain default settings,
   * so you can provide the complete visualization settings object to `alertType`
   * for taking those into account
   */
  alertType(visualizationSettings) {
    const display = this.display();

    if (!this.canRun()) {
      return null;
    }

    const isLineAreaBar =
      display === "line" || display === "area" || display === "bar";

    if (display === "progress") {
      return ALERT_TYPE_PROGRESS_BAR_GOAL;
    } else if (isLineAreaBar) {
      const vizSettings = visualizationSettings
        ? visualizationSettings
        : this.card().visualization_settings;

      const goalEnabled = vizSettings["graph.show_goal"];
      const hasSingleYAxisColumn =
        vizSettings["graph.metrics"] &&
        vizSettings["graph.metrics"].length === 1;

      // We don't currently support goal alerts for multiseries question
      if (goalEnabled && hasSingleYAxisColumn) {
        return ALERT_TYPE_TIMESERIES_GOAL;
      } else {
        return ALERT_TYPE_ROWS;
      }
    } else {
      return ALERT_TYPE_ROWS;
    }
  }

  /**
   * Visualization drill-through and action widget actions
   *
   * Although most of these are essentially a way to modify the current query, having them as a part
   * of Question interface instead of Query interface makes it more convenient to also change the current visualization
   */
  summarize(aggregation) {
    const tableMetadata = this.tableMetadata();
    return this.setCard(summarize(this.card(), aggregation, tableMetadata));
  }
  breakout(b) {
    return this.setCard(breakout(this.card(), b));
  }
  pivot(breakouts = [], dimensions = []) {
    const tableMetadata = this.tableMetadata();
    return this.setCard(
      // $FlowFixMe: tableMetadata could be null
      pivot(this.card(), tableMetadata, breakouts, dimensions),
    );
  }
  filter(operator, column, value) {
    return this.setCard(filter(this.card(), operator, column, value));
  }
  drillUnderlyingRecords(dimensions) {
    return this.setCard(drillUnderlyingRecords(this.card(), dimensions));
  }
  toUnderlyingRecords(): ?Question {
    const newCard = toUnderlyingRecords(this.card());
    if (newCard) {
      return this.setCard(newCard);
    }
  }
  toUnderlyingData(): Question {
    return this.setDisplay("table");
  }

  composeThisQuery(): ?Question {
    const SAVED_QUESTIONS_FAUX_DATABASE = -1337;

    if (this.id()) {
      const card = {
        display: "table",
        dataset_query: {
          type: "query",
          database: SAVED_QUESTIONS_FAUX_DATABASE,
          query: {
            source_table: "card__" + this.id(),
          },
        },
      };
      return this.setCard(card);
    }
  }

  drillPK(field: Field, value: Value): ?Question {
    const query = this.query();
    if (query instanceof StructuredQuery) {
      return query
        .reset()
        .setTable(field.table)
        .addFilter(["=", ["field-id", field.id], value])
        .question();
    }
  }

  // deprecated
  tableMetadata(): ?Table {
    const query = this.query();
    if (query instanceof StructuredQuery) {
      return query.table();
    } else {
      return null;
    }
  }

  mode(): ?Mode {
    return Mode.forQuestion(this);
  }

  /**
   * A user-defined name for the question
   */
  displayName(): ?string {
    return this._card && this._card.name;
  }

  setDisplayName(name: String) {
    return this.setCard(assoc(this.card(), "name", name));
  }

  collectionId(): ?number {
    return this._card && this._card.collection_id;
  }

  setCollectionId(collectionId: number) {
    return this.setCard(assoc(this.card(), "collection_id", collectionId));
  }

  id(): number {
    return this._card && this._card.id;
  }

  isSaved(): boolean {
    return !!this.id();
  }

  publicUUID(): string {
    return this._card && this._card.public_uuid;
  }

  getUrl(originalQuestion?: Question): string {
    const isDirty =
      !originalQuestion || this.isDirtyComparedTo(originalQuestion);

    return isDirty
      ? Urls.question(null, this._serializeForUrl())
      : Urls.question(this.id(), "");
  }

  setResultsMetadata(resultsMetadata) {
    let metadataColumns = resultsMetadata && resultsMetadata.columns;
    let metadataChecksum = resultsMetadata && resultsMetadata.checksum;

    return this.setCard({
      ...this.card(),
      result_metadata: metadataColumns,
      metadata_checksum: metadataChecksum,
    });
  }

  /**
   * Runs the query and returns an array containing results for each single query.
   *
   * If we have a saved and clean single-query question, we use `CardApi.query` instead of a ad-hoc dataset query.
   * This way we benefit from caching and query optimizations done by Metabase backend.
   */
  async apiGetResults({
    cancelDeferred,
    isDirty = false,
    ignoreCache = false,
  } = {}): Promise<[Dataset]> {
    // TODO Atte Keinänen 7/5/17: Should we clean this query with Query.cleanQuery(query) before executing it?

    const canUseCardApiEndpoint = !isDirty && this.isSaved();

    const parameters = this.parametersList()
      // include only parameters that have a value applied
      .filter(param => _.has(param, "value"))
      // only the superset of parameters object that API expects
      .map(param => _.pick(param, "type", "target", "value"));

    if (canUseCardApiEndpoint) {
      const queryParams = {
        cardId: this.id(),
        ignore_cache: ignoreCache,
        parameters,
      };

      return [
        await CardApi.query(queryParams, {
          cancelled: cancelDeferred.promise,
        }),
      ];
    } else {
      const getDatasetQueryResult = datasetQuery => {
        const datasetQueryWithParameters = {
          ...datasetQuery,
          parameters,
        };

        return MetabaseApi.dataset(
          datasetQueryWithParameters,
          cancelDeferred ? { cancelled: cancelDeferred.promise } : {},
        );
      };

      const datasetQueries = this.atomicQueries().map(query =>
        query.datasetQuery(),
      );
      return Promise.all(datasetQueries.map(getDatasetQueryResult));
    }
  }

  async apiCreate() {
    const createdCard = await CardApi.create(this.card());
    return this.setCard(createdCard);
  }

  async apiUpdate() {
    const updatedCard = await CardApi.update(this.card());
    return this.setCard(updatedCard);
  }

  // TODO: Fix incorrect Flow signature
  parameters(): ParameterObject[] {
    return getParametersWithExtras(this.card(), this._parameterValues);
  }

  parametersList(): ParameterObject[] {
    // $FlowFixMe
    return (Object.values(this.parameters()): ParameterObject[]);
  }

  // predicate function that dermines if the question is "dirty" compared to the given question
  isDirtyComparedTo(originalQuestion: Question) {
    // TODO Atte Keinänen 6/8/17: Reconsider these rules because they don't completely match
    // the current implementation which uses original_card_id for indicating that question has a lineage

    // The rules:
    //   - if it's new, then it's dirty when
    //       1) there is a database/table chosen or
    //       2) when there is any content on the native query
    //   - if it's saved, then it's dirty when
    //       1) the current card doesn't match the last saved version

    if (!this._card) {
      return false;
    } else if (!this._card.id) {
      if (
        this._card.dataset_query.query &&
        this._card.dataset_query.query.source_table
      ) {
        return true;
      } else if (
        this._card.dataset_query.type === "native" &&
        !_.isEmpty(this._card.dataset_query.native.query)
      ) {
        return true;
      } else {
        return false;
      }
    } else {
      const origCardSerialized = originalQuestion._serializeForUrl({
        includeOriginalCardId: false,
      });
      const currentCardSerialized = this._serializeForUrl({
        includeOriginalCardId: false,
      });
      return currentCardSerialized !== origCardSerialized;
    }
  }

  // Internal methods
  _serializeForUrl({ includeOriginalCardId = true } = {}) {
    const cleanedQuery = this.query().clean();

    const cardCopy = {
      name: this._card.name,
      description: this._card.description,
      dataset_query: cleanedQuery.datasetQuery(),
      display: this._card.display,
      parameters: this._card.parameters,
      visualization_settings: this._card.visualization_settings,
      ...(includeOriginalCardId
        ? { original_card_id: this._card.original_card_id }
        : {}),
    };

    return Card_DEPRECATED.utf8_to_b64url(JSON.stringify(cardCopy));
  }
}