Add comments count endpoint

.env.example

@@ -11,3 +11,5 @@ SUPABASE_INSTALLATION_ACCESS_TOKENS_TABLE=installation_access_tokens
 # The usage is different from the values in giscus.json.
 ORIGINS=["https://giscus.app", "https://giscus.vercel.app"]
 ORIGINS_REGEX=["http://localhost:[0-9]+"]
+
+ENABLE_ADDITIONAL_PAGES=true

lib/types/github.ts

@@ -79,6 +79,12 @@ export interface GRepositoryDiscussion {
  };
 }
 
+export interface GRepositoryDiscussionCount {
+ comments: {
+ totalCount: number;
+ }
+}
+
 export interface GDiscussionCategory {
  id: string;
  name: string;

pages/api/discussions/categories.ts

@@ -1,8 +1,12 @@
 import type { NextApiRequest, NextApiResponse } from 'next';
 import { addCorsHeaders } from '../../../lib/cors';
 import { ICategories, IError } from '../../../lib/types/adapter';
+import { handleGithubDiscussionResponse } from '../../../services/github/errors';
 import { getAppAccessToken } from '../../../services/github/getAppAccessToken';
-import { getDiscussionCategories } from '../../../services/github/getDiscussionCategories';
+import {
+ getDiscussionCategories,
+ GetDiscussionCategoriesResponse,
+} from '../../../services/github/getDiscussionCategories';
 
 export default async function DiscussionCategoriesApi(
  req: NextApiRequest,
@@ -24,17 +28,18 @@ export default async function DiscussionCategoriesApi(
  }
 
  const response = await getDiscussionCategories(params, token);
+ const handledResponse = handleGithubDiscussionResponse<GetDiscussionCategoriesResponse['data']>(
+ response,
+ params.repo,
+ );
 
- if ('message' in response) {
- res.status(500).json({ error: response.message });
- return;
+ if ('error' in handledResponse) {
+ return res.status(handledResponse.status).json({ error: handledResponse.error });
  }
 
  const {
- data: {
- search: { nodes: repositories },
- },
- } = response;
+ search: { nodes: repositories },
+ } = handledResponse;
 
  const repository = repositories[0];
  if (!repository) {

pages/api/discussions/comments-count.ts

@@ -0,0 +1,62 @@
+import { NextApiRequest, NextApiResponse } from 'next';
+import { IError } from '../../../lib/types/adapter';
+import { DiscussionQuery } from '../../../lib/types/common';
+import { handleGithubDiscussionResponse } from '../../../services/github/errors';
+import { getAppAccessToken } from '../../../services/github/getAppAccessToken';
+import {
+ getDiscussionCommentsCount,
+ GetDiscussionCommentsCountResponse,
+} from '../../../services/github/getDiscussionCommentsCount';
+
+export default async function getCommentsCount(
+ req: NextApiRequest,
+ res: NextApiResponse<number | IError>,
+) {
+ if (!process.env.ENABLE_ADDITIONAL_PAGES) {
+ return res.status(404).end();
+ }
+
+ const params: DiscussionQuery = {
+ repo: req.query.repo as string,
+ term: req.query.term as string,
+ number: +req.query.number,
+ category: req.query.category as string,
+ };
+
+ const userToken = req.headers.authorization?.split('Bearer ')[1];
+ let token = userToken;
+ if (!token) {
+ try {
+ token = await getAppAccessToken(params.repo);
+ } catch (error) {
+ res.status(403).json({ error: error.message });
+ return;
+ }
+ }
+
+ const response = await getDiscussionCommentsCount(params, token);
+
+ const handledResponse = handleGithubDiscussionResponse<
+ GetDiscussionCommentsCountResponse['data']
+ >(response, params.repo, userToken);
+
+ if ('error' in handledResponse) {
+ return res.status(handledResponse.status).json({ error: handledResponse.error });
+ }
+
+ const discussion =
+ 'search' in handledResponse
+ ? handledResponse.search.nodes[0] ?? null
+ : handledResponse.repository.discussion;
+
+ if (!discussion) {
+ res.status(404).json({ error: 'Discussion not found' });
+ return;
+ }
+
+ res.setHeader(
+ 'Cache-Control',
+ 'public, s-maxage=3600, stale-while-revalidate=3600, stale-if-error=86400',
+ );
+ res.status(200).json(discussion.comments.totalCount);
+}

pages/api/discussions/index.ts

@@ -1,11 +1,12 @@
 import type { NextApiRequest, NextApiResponse } from 'next';
-import { getDiscussion } from '../../../services/github/getDiscussion';
+import { getDiscussion, GetDiscussionResponse } from '../../../services/github/getDiscussion';
 import { adaptDiscussion } from '../../../lib/adapter';
 import { IError, IGiscussion } from '../../../lib/types/adapter';
 import { createDiscussion } from '../../../services/github/createDiscussion';
 import { GRepositoryDiscussion } from '../../../lib/types/github';
 import { getAppAccessToken } from '../../../services/github/getAppAccessToken';
 import { addCorsHeaders } from '../../../lib/cors';
+import { handleGithubDiscussionResponse } from '../../../services/github/errors';
 
 async function get(req: NextApiRequest, res: NextApiResponse<IGiscussion | IError>) {
  const params = {
@@ -34,49 +35,25 @@ async function get(req: NextApiRequest, res: NextApiResponse<IGiscussion | IErro
  }
 
  const response = await getDiscussion(params, token);
-
- if ('message' in response) {
- if (response.message.includes('Bad credentials')) {
- res.status(403).json({ error: response.message });
- return;
- }
- res.status(500).json({ error: response.message });
- return;
- }
-
- if ('errors' in response) {
- const error = response.errors[0];
- if (error?.message?.includes('API rate limit exceeded')) {
- let message = `API rate limit exceeded for ${params.repo}`;
- if (!userToken) {
- message += '. Sign in to increase the rate limit';
- }
- res.status(429).json({ error: message });
- return;
- }
-
- console.error(response);
- const message = response.errors.map?.(({ message }) => message).join('. ') || 'Unknown error';
- res.status(500).json({ error: message });
- return;
- }
-
- const { data } = response;
- if (!data) {
- console.error(response);
- res.status(500).json({ error: 'Unable to fetch discussion' });
- return;
+ const handledResponse = handleGithubDiscussionResponse<GetDiscussionResponse['data']>(
+ response,
+ params.repo,
+ userToken,
+ );
+
+ if ('error' in handledResponse) {
+ return res.status(handledResponse.status).json({ error: handledResponse.error });
  }
 
- const { viewer } = data;
+ const { viewer } = handledResponse;
 
  let discussion: GRepositoryDiscussion;
- if ('search' in data) {
- const { search } = data;
+ if ('search' in handledResponse) {
+ const { search } = handledResponse;
  const { discussionCount, nodes } = search;
  discussion = discussionCount > 0 ? nodes[0] : null;
  } else {
- discussion = data.repository.discussion;
+ discussion = handledResponse.repository.discussion;
  }
 
  if (!discussion) {

services/github/errors.ts

@@ -0,0 +1,36 @@
+import { GError, GMultipleErrors } from '../../lib/types/github';
+
+export function handleGithubDiscussionResponse<Data>(
+ response: { data: Data } | GError | GMultipleErrors,
+ repo: string,
+ userToken?: string,
+) {
+ if ('message' in response) {
+ if (response.message.includes('Bad credentials')) {
+ return { status: 403, error: response.message };
+ }
+ return { status: 500, error: response.message };
+ }
+
+ if ('errors' in response) {
+ const error = response.errors[0];
+ if (error?.message?.includes('API rate limit exceeded')) {
+ let message = `API rate limit exceeded for ${repo}`;
+ if (!userToken) {
+ message += '. Sign in to increase the rate limit';
+ }
+ return { status: 429, error: message };
+ }
+
+ console.error(response);
+ const message = response.errors.map?.(({ message }) => message).join('. ') || 'Unknown error';
+ return { status: 500, error: message };
+ }
+
+ const { data } = response;
+ if (!data) {
+ console.error(response);
+ return { status: 500, error: 'Unable to fetch discussion' };
+ }
+ return data;
+}

services/github/getDiscussion.ts

@@ -1,7 +1,6 @@
 import { DiscussionQuery, PaginationParams } from '../../lib/types/common';
-import { GUser, GRepositoryDiscussion, GError, GMultipleErrors } from '../../lib/types/github';
-import { parseRepoWithOwner } from '../../lib/utils';
-import { GITHUB_GRAPHQL_API_URL } from '../config';
+import { GUser, GRepositoryDiscussion } from '../../lib/types/github';
+import { githubDiscussionGraphqlRequest } from './graphql';
 
 const DISCUSSION_QUERY = `
  id
@@ -138,32 +137,18 @@ interface SpecificResponse {
 
 export type GetDiscussionResponse = SearchResponse | SpecificResponse;
 
-export async function getDiscussion(
- params: GetDiscussionParams,
- token: string,
-): Promise<GetDiscussionResponse | GError | GMultipleErrors> {
+export async function getDiscussion(params: GetDiscussionParams, token: string) {
  const { repo: repoWithOwner, term, number, category, ...pagination } = params;
 
- // Force repo to lowercase to prevent GitHub's bug when using category in query.
- // https://github.com/giscus/giscus/issues/118
- const repo = repoWithOwner.toLowerCase();
- const categoryQuery = category ? `category:${JSON.stringify(category)}` : '';
- const query = `repo:${repo} ${categoryQuery} in:title ${term}`;
  const gql = GET_DISCUSSION_QUERY(number ? 'number' : 'term');
 
- return fetch(GITHUB_GRAPHQL_API_URL, {
- method: 'POST',
- headers: { Authorization: `Bearer ${token}` },
-
- body: JSON.stringify({
- query: gql,
- variables: {
- repo,
- query,
- number,
- ...parseRepoWithOwner(repo),
- ...pagination,
- },
- }),
- }).then((r) => r.json());
+ return githubDiscussionGraphqlRequest<GetDiscussionResponse, PaginationParams>({
+ gql,
+ repoWithOwner,
+ category,
+ term,
+ token,
+ number,
+ variables: pagination,
+ });
 }

services/github/getDiscussionCommentsCount.ts

@@ -0,0 +1,64 @@
+import { DiscussionQuery } from '../../lib/types/common';
+import { GRepositoryDiscussionCount } from '../../lib/types/github';
+import { githubDiscussionGraphqlRequest } from './graphql';
+
+const DISCUSSION_QUERY = `
+ comments {
+ totalCount
+ }`;
+
+const SEARCH_QUERY = `
+ search(type: DISCUSSION last: 1 query: $query) {
+ nodes {
+ ... on Discussion {
+ ${DISCUSSION_QUERY}
+ }
+ }
+ }`;
+
+const SPECIFIC_QUERY = `
+ repository(owner: $owner, name: $name) {
+ discussion(number: $number) {
+ ${DISCUSSION_QUERY}
+ }
+ }
+`;
+
+const GET_DISCUSSION_COMMENTS_COUNT_QUERY = (type: 'term' | 'number') => `
+ query(${type === 'term' ? '$query: String!' : '$owner: String! $name: String! $number: Int!'}) {
+ ${type === 'term' ? SEARCH_QUERY : SPECIFIC_QUERY}
+ }`;
+
+interface SearchResponse {
+ data: {
+ search: {
+ nodes: Array<GRepositoryDiscussionCount>;
+ };
+ };
+}
+
+interface SpecificResponse {
+ data: {
+ repository: {
+ discussion: GRepositoryDiscussionCount;
+ };
+ };
+}
+
+export type GetDiscussionCommentsCountResponse = SearchResponse | SpecificResponse;
+
+export async function getDiscussionCommentsCount(params: DiscussionQuery, token: string) {
+ const { repo: repoWithOwner, term, number, category } = params;
+
+ const gql = GET_DISCUSSION_COMMENTS_COUNT_QUERY(number ? 'number' : 'term');
+
+ return githubDiscussionGraphqlRequest<GetDiscussionCommentsCountResponse>({
+ gql,
+ repoWithOwner,
+ category,
+ term,
+ token,
+ number,
+ variables: {},
+ });
+}

services/github/graphql.ts

@@ -0,0 +1,46 @@
+import { GError, GMultipleErrors } from '../../lib/types/github';
+import { parseRepoWithOwner } from '../../lib/utils';
+import { GITHUB_GRAPHQL_API_URL } from '../config';
+
+export async function githubDiscussionGraphqlRequest<
+ Response,
+ AdditionalVariables = Record<string, never>,
+>({
+ gql,
+ repoWithOwner,
+ category,
+ term,
+ token,
+ number,
+ variables,
+}: {
+ gql: string;
+ repoWithOwner: string;
+ category: string;
+ term: string;
+ token: string;
+ number: number;
+ variables: AdditionalVariables;
+}): Promise<Response | GError | GMultipleErrors> {
+ // Force repo to lowercase to prevent GitHub's bug when using category in query.
+ // https://github.com/giscus/giscus/issues/118
+ const repo = repoWithOwner.toLowerCase();
+ const categoryQuery = category ? `category:${JSON.stringify(category)}` : '';
+ const query = `repo:${repo} ${categoryQuery} in:title ${term}`;
+
+ return fetch(GITHUB_GRAPHQL_API_URL, {
+ method: 'POST',
+ headers: { Authorization: `Bearer ${token}` },
+
+ body: JSON.stringify({
+ query: gql,
+ variables: {
+ repo,
+ query,
+ number,
+ ...parseRepoWithOwner(repo),
+ ...variables,
+ },
+ }),
+ }).then((r) => r.json());
+}