Add HEAD request. #104 (#109)

* Add HEAD request. #104

* clean up

* todo

* style

* add passing tests

* Update test/integration.js

Co-authored-by: Miroslav Bajtoš <[email protected]>

* add Accept header

* fix lint

---------

Co-authored-by: Miroslav Bajtoš <[email protected]>

Author: juliangruber

lib/spark.js

@@ -78,6 +78,9 @@ export default class Spark {
     stats.providerAddress = provider.address
 
     await this.fetchCAR(provider.protocol, provider.address, retrieval.cid, stats)
+    if (stats.protocol === 'http') {
+      await this.testHeadRequest(provider.address, retrieval.cid, stats)
+    }
   }
 
   async fetchCAR (protocol, address, cid, stats) {
@@ -160,6 +163,25 @@ export default class Spark {
     stats.endAt = new Date()
   }
 
+  async testHeadRequest (address, cid, stats) {
+    const url = getRetrievalUrl('http', address, cid)
+    console.log(`Testing HEAD request: ${url}`)
+    try {
+      const res = await this.#fetch(url, {
+        method: 'HEAD',
+        headers: {
+          Accept: 'application/vnd.ipld.raw'
+        },
+        signal: AbortSignal.timeout(10_000)
+      })
+      stats.headStatusCode = res.status
+    } catch (err) {
+      console.error(`Failed to make HEAD request to ${address} for ${cid}`)
+      console.error(err)
+      stats.headStatusCode = mapErrorToStatusCode(err)
+    }
+  }
+
   async submitMeasurement (task, stats) {
     console.log('Submitting measurement...')
     const payload = {
@@ -263,7 +285,8 @@ export function newStats () {
     carTooLarge: false,
     byteLength: 0,
     carChecksum: null,
-    statusCode: null
+    statusCode: null,
+    headStatusCode: null
   }
 }
 

test/integration.js

@@ -42,6 +42,9 @@ test('retrieval check for our CID', async () => {
   assertProp('protocol', 'http')
   assertProp('timeout', false)
   assertProp('statusCode', 200)
+  // Note: frisbii.fly.io doesn't support HEAD requests yet
+  // https://github.com/CheckerNetwork/frisbii-on-fly/issues/3
+  assertProp('headStatusCode', 405)
   assertProp('byteLength', 200)
   assertProp('carTooLarge', false)
   // TODO - spark-api does not record this field yet

test/spark.js

@@ -69,6 +69,52 @@ test('getRetrieval', async () => {
   ])
 })
 
+test('testHeadRequest', async () => {
+  const requests = []
+  const spark = new Spark({
+    fetch: async (url, { method, headers }) => {
+      requests.push({ url: url.toString(), method, headers })
+      return {
+        status: 200
+      }
+    }
+  })
+  const stats = {}
+  await spark.testHeadRequest('/dns/frisbii.fly.dev/tcp/443/https', KNOWN_CID, stats)
+  assertEquals(stats.headStatusCode, 200)
+  assertEquals(requests, [{ url: `https://frisbii.fly.dev/ipfs/${KNOWN_CID}?dag-scope=block`, method: 'HEAD', headers: { Accept: 'application/vnd.ipld.raw' } }])
+})
+
+test('testHeadRequest - with statusCode=500', async () => {
+  const requests = []
+  const spark = new Spark({
+    fetch: async (url, { method }) => {
+      requests.push({ url: url.toString(), method })
+      return {
+        status: 500
+      }
+    }
+  })
+  const stats = {}
+  await spark.testHeadRequest('/dns/frisbii.fly.dev/tcp/443/https', KNOWN_CID, stats)
+  assertEquals(stats.headStatusCode, 500)
+  assertEquals(requests, [{ url: `https://frisbii.fly.dev/ipfs/${KNOWN_CID}?dag-scope=block`, method: 'HEAD' }])
+})
+
+test('testHeadRequest - with network failure', async () => {
+  const requests = []
+  const spark = new Spark({
+    fetch: async (url, { method }) => {
+      requests.push({ url: url.toString(), method })
+      throw new Error()
+    }
+  })
+  const stats = {}
+  await spark.testHeadRequest('/dns/frisbii.fly.dev/tcp/443/https', KNOWN_CID, stats)
+  assertEquals(stats.headStatusCode, 600)
+  assertEquals(requests, [{ url: `https://frisbii.fly.dev/ipfs/${KNOWN_CID}?dag-scope=block`, method: 'HEAD' }])
+})
+
 test('fetchCAR - http', async () => {
   const requests = []
   const spark = new Spark({