Add support for configurable domain sub-paths (#74)

Author: brendan-kellam

CHANGELOG.md

@@ -7,6 +7,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Added
+
+- Added `DOMAIN_SUB_PATH` environment variable to allow overriding the default domain subpath. ([#74](https://github.com/sourcebot-dev/sourcebot/pull/74))
+
 ## [2.4.3] - 2024-11-18
 
 ### Changed

Dockerfile

@@ -26,6 +26,8 @@ ENV NEXT_TELEMETRY_DISABLED=1
 # @see: https://phase.dev/blog/nextjs-public-runtime-variables/
 ARG NEXT_PUBLIC_SOURCEBOT_TELEMETRY_DISABLED=BAKED_NEXT_PUBLIC_SOURCEBOT_TELEMETRY_DISABLED
 ARG NEXT_PUBLIC_SOURCEBOT_VERSION=BAKED_NEXT_PUBLIC_SOURCEBOT_VERSION
+# @note: leading "/" is required for the basePath property. @see: https://nextjs.org/docs/app/api-reference/next-config-js/basePath
+ARG NEXT_PUBLIC_DOMAIN_SUB_PATH=/BAKED_NEXT_PUBLIC_DOMAIN_SUB_PATH
 RUN yarn workspace @sourcebot/web build
 
 # ------ Build Backend ------
@@ -54,6 +56,11 @@ RUN echo "Sourcebot Version: $SOURCEBOT_VERSION"
 # Valid values are: debug, info, warn, error
 ENV SOURCEBOT_LOG_LEVEL=info
 
+# Configures the sub-path of the domain to serve Sourcebot from.
+# For example, if DOMAIN_SUB_PATH is set to "/sb", Sourcebot
+# will serve from http(s)://example.com/sb
+ENV DOMAIN_SUB_PATH=/
+
 # @note: This is also set in .env
 ENV POSTHOG_KEY=phc_VFn4CkEGHRdlVyOOw8mfkoj1DKVoG6y1007EClvzAnS
 ENV NEXT_PUBLIC_POSTHOG_KEY=$POSTHOG_KEY

entrypoint.sh

@@ -70,23 +70,69 @@ fi
 
 echo -e "\e[34m[Info] Using config file at: '$CONFIG_PATH'.\e[0m"
 
-# Update nextjs public env variables w/o requiring a rebuild.
+# Update NextJs public env variables w/o requiring a rebuild.
 # @see: https://phase.dev/blog/nextjs-public-runtime-variables/
+{
+    # Infer NEXT_PUBLIC_SOURCEBOT_TELEMETRY_DISABLED if it is not set
+    if [ -z "$NEXT_PUBLIC_SOURCEBOT_TELEMETRY_DISABLED" ] && [ ! -z "$SOURCEBOT_TELEMETRY_DISABLED" ]; then
+        export NEXT_PUBLIC_SOURCEBOT_TELEMETRY_DISABLED="$SOURCEBOT_TELEMETRY_DISABLED"
+    fi
 
-# Infer NEXT_PUBLIC_SOURCEBOT_TELEMETRY_DISABLED if it is not set
-if [ -z "$NEXT_PUBLIC_SOURCEBOT_TELEMETRY_DISABLED" ] && [ ! -z "$SOURCEBOT_TELEMETRY_DISABLED" ]; then
-    export NEXT_PUBLIC_SOURCEBOT_TELEMETRY_DISABLED="$SOURCEBOT_TELEMETRY_DISABLED"
-fi
+    # Infer NEXT_PUBLIC_SOURCEBOT_VERSION if it is not set
+    if [ -z "$NEXT_PUBLIC_SOURCEBOT_VERSION" ] && [ ! -z "$SOURCEBOT_VERSION" ]; then
+        export NEXT_PUBLIC_SOURCEBOT_VERSION="$SOURCEBOT_VERSION"
+    fi
 
-# Infer NEXT_PUBLIC_SOURCEBOT_VERSION if it is not set
-if [ -z "$NEXT_PUBLIC_SOURCEBOT_VERSION" ] && [ ! -z "$SOURCEBOT_VERSION" ]; then
-    export NEXT_PUBLIC_SOURCEBOT_VERSION="$SOURCEBOT_VERSION"
-fi
+    # Iterate over all .js files in .next & public, making substitutions for the `BAKED_` sentinal values
+    # with their actual desired runtime value.
+    find /app/packages/web/public /app/packages/web/.next -type f -name "*.js" |
+    while read file; do
+        sed -i "s|BAKED_NEXT_PUBLIC_SOURCEBOT_TELEMETRY_DISABLED|${NEXT_PUBLIC_SOURCEBOT_TELEMETRY_DISABLED}|g" "$file"
+        sed -i "s|BAKED_NEXT_PUBLIC_SOURCEBOT_VERSION|${NEXT_PUBLIC_SOURCEBOT_VERSION}|g" "$file"
+    done
+}
+
+
+# Update specifically NEXT_PUBLIC_DOMAIN_SUB_PATH w/o requiring a rebuild.
+# Ultimately, the DOMAIN_SUB_PATH sets the `basePath` param in the next.config.mjs.
+# Similar to above, we pass in a `BAKED_` sentinal value into next.config.mjs at build
+# time. Unlike above, the `basePath` configuration is set in files other than just javascript
+# code (e.g., manifest files, css files, etc.), so this section has subtle differences.
+#
+# @see: https://nextjs.org/docs/app/api-reference/next-config-js/basePath
+# @see: https://phase.dev/blog/nextjs-public-runtime-variables/
+{
+    if [ ! -z "$DOMAIN_SUB_PATH" ]; then
+        # If the sub-path is "/", this creates problems with certain replacements. For example:
+        # /BAKED_NEXT_PUBLIC_DOMAIN_SUB_PATH/_next/image -> //_next/image (notice the double slash...)
+        # To get around this, we default to an empty sub-path, which is the default when no sub-path is defined.
+        if [ "$DOMAIN_SUB_PATH" = "/" ]; then
+            DOMAIN_SUB_PATH=""
+
+        # Otherwise, we need to ensure that the sub-path starts with a slash, since this is a requirement
+        # for the basePath property. For example, assume DOMAIN_SUB_PATH=/bot, then:
+        # /BAKED_NEXT_PUBLIC_DOMAIN_SUB_PATH/_next/image -> /bot/_next/image
+        elif [[ ! "$DOMAIN_SUB_PATH" =~ ^/ ]]; then
+            DOMAIN_SUB_PATH="/$DOMAIN_SUB_PATH"
+        fi
+    fi
+
+    if [ ! -z "$DOMAIN_SUB_PATH" ]; then
+        echo -e "\e[34m[Info] DOMAIN_SUB_PATH was set to "$DOMAIN_SUB_PATH". Overriding default path.\e[0m"
+    fi
+
+    # Always set NEXT_PUBLIC_DOMAIN_SUB_PATH to DOMAIN_SUB_PATH (even if it is empty!!)
+    export NEXT_PUBLIC_DOMAIN_SUB_PATH="$DOMAIN_SUB_PATH"
+
+    # Iterate over _all_ files in the web directory, making substitutions for the `BAKED_` sentinal values
+    # with their actual desired runtime value.
+    find /app/packages/web -type f |
+    while read file; do
+        # @note: the leading "/" is required here as it is included at build time. See Dockerfile.
+        sed -i "s|/BAKED_NEXT_PUBLIC_DOMAIN_SUB_PATH|${NEXT_PUBLIC_DOMAIN_SUB_PATH}|g" "$file"
+    done
+}
 
-find /app/packages/web/public /app/packages/web/.next -type f -name "*.js" |
-while read file; do
-    sed -i "s|BAKED_NEXT_PUBLIC_SOURCEBOT_TELEMETRY_DISABLED|${NEXT_PUBLIC_SOURCEBOT_TELEMETRY_DISABLED}|g" "$file"
-    sed -i "s|BAKED_NEXT_PUBLIC_SOURCEBOT_VERSION|${NEXT_PUBLIC_SOURCEBOT_VERSION}|g" "$file"
-done
 
+# Run supervisord
 exec supervisord -c /etc/supervisor/conf.d/supervisord.conf

packages/web/next.config.mjs

@@ -20,7 +20,12 @@ const nextConfig = {
         ];
     },
     // This is required to support PostHog trailing slash API requests
-    skipTrailingSlashRedirect: true, 
+    skipTrailingSlashRedirect: true,
+
+    // @note: this is evaluated at build time.
+    ...(process.env.NEXT_PUBLIC_DOMAIN_SUB_PATH ? {
+        basePath: process.env.NEXT_PUBLIC_DOMAIN_SUB_PATH,
+    } : {})
 };
 
 export default nextConfig;

packages/web/src/app/api/(client)/client.ts

@@ -1,8 +1,12 @@
+'use client';
+
+import { NEXT_PUBLIC_DOMAIN_SUB_PATH } from "@/lib/environment.client";
 import { fileSourceResponseSchema, listRepositoriesResponseSchema, searchResponseSchema } from "@/lib/schemas";
 import { FileSourceRequest, FileSourceResponse, ListRepositoriesResponse, SearchRequest, SearchResponse } from "@/lib/types";
 
 export const search = async (body: SearchRequest): Promise<SearchResponse> => {
-    const result = await fetch(`/api/search`, {
+    const path = resolveServerPath("/api/search");
+    const result = await fetch(path, {
         method: "POST",
         headers: {
             "Content-Type": "application/json",
@@ -14,7 +18,8 @@ export const search = async (body: SearchRequest): Promise<SearchResponse> => {
 }
 
 export const fetchFileSource = async (body: FileSourceRequest): Promise<FileSourceResponse> => {
-    const result = await fetch(`/api/source`, {
+    const path = resolveServerPath("/api/source");
+    const result = await fetch(path, {
         method: "POST",
         headers: {
             "Content-Type": "application/json",
@@ -26,7 +31,8 @@ export const fetchFileSource = async (body: FileSourceRequest): Promise<FileSour
 }
 
 export const getRepos = async (): Promise<ListRepositoriesResponse> => {
-    const result = await fetch('/api/repos', {
+    const path = resolveServerPath("/api/repos");
+    const result = await fetch(path, {
         method: "GET",
         headers: {
             "Content-Type": "application/json",
@@ -35,3 +41,12 @@ export const getRepos = async (): Promise<ListRepositoriesResponse> => {
 
     return listRepositoriesResponseSchema.parse(result);
 }
+
+/**
+ * Given a subpath to a api route on the server (e.g., /api/search),
+ * returns the full path to that route on the server, taking into account
+ * the base path (if any).
+ */
+export const resolveServerPath = (path: string) => {
+    return `${NEXT_PUBLIC_DOMAIN_SUB_PATH}${path}`;
+}

packages/web/src/app/posthogProvider.tsx

@@ -2,11 +2,15 @@
 import { NEXT_PUBLIC_POSTHOG_KEY, NEXT_PUBLIC_POSTHOG_UI_HOST, NEXT_PUBLIC_SOURCEBOT_TELEMETRY_DISABLED } from '@/lib/environment.client'
 import posthog from 'posthog-js'
 import { PostHogProvider } from 'posthog-js/react'
+import { resolveServerPath } from './api/(client)/client'
 
 if (typeof window !== 'undefined') {
     if (!NEXT_PUBLIC_SOURCEBOT_TELEMETRY_DISABLED) {
+        // @see next.config.mjs for path rewrites to the "/ingest" route.
+        const posthogHostPath = resolveServerPath('/ingest');
+
         posthog.init(NEXT_PUBLIC_POSTHOG_KEY!, {
-            api_host: "/ingest",
+            api_host: posthogHostPath,
             ui_host: NEXT_PUBLIC_POSTHOG_UI_HOST,
             person_profiles: 'identified_only',
             capture_pageview: false, // Disable automatic pageview capture

packages/web/src/lib/environment.client.ts

@@ -8,3 +8,4 @@ export const NEXT_PUBLIC_POSTHOG_UI_HOST = getEnv(process.env.NEXT_PUBLIC_POSTHO
 export const NEXT_PUBLIC_POSTHOG_ASSET_HOST = getEnv(process.env.NEXT_PUBLIC_POSTHOG_ASSET_HOST);
 export const NEXT_PUBLIC_SOURCEBOT_TELEMETRY_DISABLED = getEnvBoolean(process.env.NEXT_PUBLIC_SOURCEBOT_TELEMETRY_DISABLED, false);
 export const NEXT_PUBLIC_SOURCEBOT_VERSION = getEnv(process.env.NEXT_PUBLIC_SOURCEBOT_VERSION, "unknown");
+export const NEXT_PUBLIC_DOMAIN_SUB_PATH = getEnv(process.env.NEXT_PUBLIC_DOMAIN_SUB_PATH, "");