feat: add endpoint for maps plugin to get info about custom map

src/fastify-plugins/maps.js

@@ -1,3 +1,5 @@
+import fs from 'node:fs/promises'
+import path from 'node:path'
 import { fetch } from 'undici'
 import { Server as SMPServerPlugin } from 'styled-map-package'
 
@@ -19,9 +21,39 @@ export const FALLBACK_MAP_PREFIX = 'fallback'
 /** @type {FastifyPluginAsync<MapsPluginOpts>} */
 export async function plugin(fastify, opts) {
   if (opts.customMapPath) {
+    const { customMapPath } = opts
+
+    fastify.get(`/${CUSTOM_MAP_PREFIX}/info`, async () => {
+      const baseUrl = new URL(fastify.prefix, fastify.listeningOrigin)
+
+      if (!baseUrl.href.endsWith('/')) {
+        baseUrl.href += '/'
+      }
+
+      const style = await (
+        await fetch(new URL(`${CUSTOM_MAP_PREFIX}/style.json`, baseUrl))
+      ).json()
+
+      const stats = await fs.stat(customMapPath)
+
+      const styleJsonName =
+        typeof style === 'object' &&
+        style &&
+        'name' in style &&
+        typeof style.name === 'string'
+          ? style.name
+          : undefined
+
+      return {
+        created: stats.ctime,
+        size: stats.size,
+        name: styleJsonName || path.parse(customMapPath).name,
+      }
+    })
+
     fastify.register(SMPServerPlugin, {
       prefix: CUSTOM_MAP_PREFIX,
-      filepath: opts.customMapPath,
+      filepath: customMapPath,
     })
   }
 

test/fastify-plugins/maps.js

@@ -1,4 +1,5 @@
 import assert from 'node:assert/strict'
+import path from 'node:path'
 import test from 'node:test'
 import Fastify from 'fastify'
 import { Reader } from 'styled-map-package'
@@ -13,6 +14,7 @@ import {
   DEFAULT_FALLBACK_MAP_FILE_PATH,
   DEFAULT_ONLINE_STYLE_URL,
 } from '../../src/mapeo-manager.js'
+import { hashObject } from '../../src/utils.js'
 
 const SAMPLE_SMP_FIXTURE_PATH = new URL(
   '../fixtures/maps/maplibre-demotiles.smp',
@@ -223,6 +225,77 @@ test('/style.json resolves style.json of fallback map when custom and online are
   )
 })
 
+test('custom map info endpoint not available when custom map path not provided', async (t) => {
+  const server = setup(t)
+
+  server.register(MapServerPlugin, {
+    defaultOnlineStyleUrl: DEFAULT_ONLINE_STYLE_URL,
+    fallbackMapPath: DEFAULT_FALLBACK_MAP_FILE_PATH,
+  })
+
+  const address = await server.listen()
+
+  mockAgent.enableNetConnect(new URL(address).host)
+
+  const response = await server.inject({
+    method: 'GET',
+    url: `/${CUSTOM_MAP_PREFIX}/info`,
+  })
+
+  assert.equal(response.statusCode, 404)
+})
+
+test('custom map info endpoint returns expected error when custom map is invalid', async (t) => {
+  const server = setup(t)
+
+  const nonExistentFile =
+    path.parse(SAMPLE_SMP_FIXTURE_PATH).dir + '/does/not/exist.smp'
+
+  server.register(MapServerPlugin, {
+    customMapPath: nonExistentFile,
+    defaultOnlineStyleUrl: DEFAULT_ONLINE_STYLE_URL,
+    fallbackMapPath: DEFAULT_FALLBACK_MAP_FILE_PATH,
+  })
+
+  const address = await server.listen()
+
+  mockAgent.enableNetConnect(new URL(address).host)
+
+  const response = await server.inject({
+    method: 'GET',
+    url: `/${CUSTOM_MAP_PREFIX}/info`,
+  })
+
+  assert.equal(response.statusCode, 500, 'returns server error status code')
+})
+
+test('custom map info endpoint returns expected info when available', async (t) => {
+  const server = setup(t)
+
+  server.register(MapServerPlugin, {
+    customMapPath: SAMPLE_SMP_FIXTURE_PATH,
+    defaultOnlineStyleUrl: DEFAULT_ONLINE_STYLE_URL,
+    fallbackMapPath: DEFAULT_FALLBACK_MAP_FILE_PATH,
+  })
+
+  const address = await server.listen()
+
+  mockAgent.enableNetConnect(new URL(address).host)
+
+  const response = await server.inject({
+    method: 'GET',
+    url: `/${CUSTOM_MAP_PREFIX}/info`,
+  })
+
+  assert.equal(response.statusCode, 200)
+
+  assert.equal(
+    hashObject(response.json()),
+    'ef2ae6b5a1298e608c743a91bb7fba7c55ea63427e34cfb52b808eaaa6625b61',
+    'custom map info matches snapshot'
+  )
+})
+
 /**
  * @param {import('node:test').TestContext} t
  */