Registrant country report for a challenge, to help with challenges that only allow submissions from a subset of countries

sql/reports/topcoder/registrant-countries.sql

@@ -0,0 +1,21 @@
+SELECT DISTINCT
+  res."memberHandle" AS handle,
+  mem.email AS email,
+  COALESCE(home_code.name, home_id.name, mem."homeCountryCode") AS home_country,
+  COALESCE(comp_code.name, comp_id.name, mem."competitionCountryCode") AS competition_country
+FROM resources."Resource" AS res
+JOIN resources."ResourceRole" AS rr
+  ON rr.id = res."roleId"
+LEFT JOIN members."member" AS mem
+  ON mem."userId"::text = res."memberId"
+LEFT JOIN lookups."Country" AS home_code
+  ON UPPER(home_code."countryCode") = UPPER(mem."homeCountryCode")
+LEFT JOIN lookups."Country" AS home_id
+  ON UPPER(home_id.id) = UPPER(mem."homeCountryCode")
+LEFT JOIN lookups."Country" AS comp_code
+  ON UPPER(comp_code."countryCode") = UPPER(mem."competitionCountryCode")
+LEFT JOIN lookups."Country" AS comp_id
+  ON UPPER(comp_id.id) = UPPER(mem."competitionCountryCode")
+WHERE rr.name = 'Submitter'
+  AND res."challengeId" = 'e12ee862-474a-4e40-9d2d-2699ae1dfc2a'
+ORDER BY res."memberHandle";

src/reports/topcoder/dto/registrant-countries.dto.ts

@@ -0,0 +1,11 @@
+import { Transform } from "class-transformer";
+import { IsNotEmpty, IsString } from "class-validator";
+
+export class RegistrantCountriesQueryDto {
+  @Transform(({ value }) =>
+    typeof value === "string" ? value.trim() : value,
+  )
+  @IsString()
+  @IsNotEmpty()
+  challengeId!: string;
+}

src/reports/topcoder/topcoder-reports.controller.ts

@@ -1,6 +1,8 @@
-import { Controller, Get } from "@nestjs/common";
+import { Controller, Get, Query, Res } from "@nestjs/common";
 import { ApiOperation, ApiTags } from "@nestjs/swagger";
+import { Response } from "express";
 import { TopcoderReportsService } from "./topcoder-reports.service";
+import { RegistrantCountriesQueryDto } from "./dto/registrant-countries.dto";
 
 @ApiTags("Topcoder Reports")
 @Controller("/topcoder")
@@ -13,6 +15,25 @@ export class TopcoderReportsController {
     return this.reports.getMemberCount();
   }
 
+  @Get("/registrant-countries")
+  @ApiOperation({
+    summary: "Countries of all registrants for the specified challenge",
+  })
+  async getRegistrantCountries(
+    @Query() query: RegistrantCountriesQueryDto,
+    @Res() res: Response,
+  ) {
+    const { challengeId } = query;
+    const csv = await this.reports.getRegistrantCountriesCsv(challengeId);
+    const filename =
+      challengeId.length > 0
+        ? `registrant-countries-${challengeId}.csv`
+        : "registrant-countries.csv";
+    res.setHeader("Content-Type", "text/csv");
+    res.setHeader("Content-Disposition", `attachment; filename="${filename}"`);
+    res.send(csv);
+  }
+
   @Get("/total-copilots")
   @ApiOperation({ summary: "Total number of Copilots" })
   getTotalCopilots() {

src/reports/topcoder/topcoder-reports.service.ts

@@ -2,6 +2,13 @@ import { Injectable } from "@nestjs/common";
 import { DbService } from "../../db/db.service";
 import { SqlLoaderService } from "../../common/sql-loader.service";
 
+type RegistrantCountriesRow = {
+  handle: string | null;
+  email: string | null;
+  home_country: string | null;
+  competition_country: string | null;
+};
+
 @Injectable()
 export class TopcoderReportsService {
   constructor(
@@ -387,4 +394,49 @@ export class TopcoderReportsService {
       ),
     }));
   }
+
+  async getRegistrantCountriesCsv(challengeId: string) {
+    const query = this.sql.load("reports/topcoder/registrant-countries.sql");
+    const rows = await this.db.query<RegistrantCountriesRow>(query, [
+      challengeId,
+    ]);
+    return this.rowsToCsv(rows);
+  }
+
+  private rowsToCsv(rows: RegistrantCountriesRow[]) {
+    const header = [
+      "Handle",
+      "Email",
+      "Home country",
+      "Competition country",
+    ];
+
+    const lines = [
+      header.map((value) => this.toCsvCell(value)).join(","),
+      ...rows.map((row) =>
+        [
+          row.handle,
+          row.email,
+          row.home_country,
+          row.competition_country,
+        ]
+          .map((value) => this.toCsvCell(value))
+          .join(","),
+      ),
+    ];
+
+    return lines.join("\n");
+  }
+
+  private toCsvCell(value: string | null | undefined) {
+    if (value === null || value === undefined) {
+      return "";
+    }
+    const text = String(value);
+    if (!/[",\r\n]/.test(text)) {
+      return text;
+    }
+    const escaped = text.replace(/"/g, '""');
+    return `"${escaped}"`;
+  }
 }