fix: retry IPNI requests on 5xx errors

Signed-off-by: Miroslav Bajtoš <oss@bajtos.net>

Author: bajtos

lib/ipni-client.js

@@ -1,4 +1,4 @@
-import { decodeBase64, decodeVarint } from '../vendor/deno-deps.js'
+import { decodeBase64, decodeVarint, pRetry, assertOkResponse } from '../vendor/deno-deps.js'
 
 /**
  *
@@ -10,22 +10,23 @@ import { decodeBase64, decodeVarint } from '../vendor/deno-deps.js'
  * }>}
  */
 export async function queryTheIndex (cid, providerId) {
-  const url = `https://cid.contact/cid/${encodeURIComponent(cid)}`
-
   let providerResults
   try {
-    const res = await fetch(url)
-    if (!res.ok) {
-      console.error('IPNI query failed, HTTP response: %s %s', res.status, (await res.text()).trimEnd())
-      return { indexerResult: `ERROR_${res.status}` }
-    }
-
-    const result = await res.json()
-    providerResults = result.MultihashResults.flatMap(r => r.ProviderResults)
+    providerResults = await pRetry(() => getRetrievalProviders(cid), {
+      retries: 5,
+      shouldRetry: (error) => {
+        return error.statusCode && error.statusCode >= 500
+      },
+      onFailedAttempt: (error) => {
+        console.error('IPNI query failed, retrying...\n', error)
+      }
+    })
     console.log('IPNI returned %s provider results', providerResults.length)
   } catch (err) {
     console.error('IPNI query failed.', err)
-    return { indexerResult: 'ERROR_FETCH' }
+    return {
+      indexerResult: typeof err.statusCode === 'number' ? `ERROR_${err.statusCode}` : 'ERROR_FETCH'
+    }
   }
 
   let graphsyncProvider
@@ -70,3 +71,12 @@ export async function queryTheIndex (cid, providerId) {
   console.log('All advertisements are from other miners or for unsupported protocols.')
   return { indexerResult: 'NO_VALID_ADVERTISEMENT' }
 }
+
+async function getRetrievalProviders (cid) {
+  const url = `https://cid.contact/cid/${encodeURIComponent(cid)}`
+  const res = await fetch(url)
+  await assertOkResponse(res)
+
+  const result = await res.json()
+  return result.MultihashResults.flatMap((r) => r.ProviderResults)
+}