store_backend.ts

import axios from "axios";

import { StoreInterface, DataFetchOptions, TableData } from "./store";

function transformValue(x: any): any {
  if (x === "inf") {
    return Infinity;
  } else if (x === "-inf") {
    return -Infinity;
  } else {
    return x;
  }
}

export class StoreBackend implements StoreInterface {
  // TODO: this needs to be dynamic
  url = "http://127.0.0.1:5000";

  async fetchColumns(): Promise<string[]> {
    const response = await axios.get(`${this.url}/api/get_columns`);
    return response.data as string[];
  }

  async fetchNumPages(paginationSize: number, filter?: string): Promise<number> {
    const response = await axios.get(`${this.url}/api/get_num_pages`, {
      params: {
        paginationSize: paginationSize,
        filter: filter,
      },
    });
    return response.data as number;
  }

  async fetchData(opts: DataFetchOptions): Promise<TableData> {
    const response = await axios.get(`${this.url}/api/get_data`, {
      params: opts,
    });
    console.log("Received response...");
    /*
    let tableData = response.data;
    console.log(tableData)
    let transformedData = fn.mapEntries(tableData, (k, v) => ({
      columnName: k,
      values: v as string[],
    }))
    console.log(transformedData)
    */
    if (typeof response.data === "string") {
      // Ugly axios bug: It swallows JSON.parse exceptions...
      // https://github.com/axios/axios/issues/1723
      // Try explicit parse to see exception...
      const parsed = JSON.parse(response.data) as TableData;
      return parsed;
    }
    const parsed = response.data as TableData;

    // Transform values to account for JSON sentinels
    for (let j = 0; j < parsed.length; j++) {
      for (let i = 0; i < parsed[j].values.length; i++) {
        parsed[j].values[i] = transformValue(parsed[j].values[i]);
      }
    }

    return parsed;
  }
}