Request for non-existing resource responds with 400 (runtime)

[tripodsan]

Description
a request with a x-strain cookie of strain that does not exist returns a 400.

To Reproduce

$ curl -s -D - -b "X-Strain=foo"  -H X-Debug:true  https://www.project-helix.io/client/README.html
HTTP/2 400
access-control-allow-headers: Authorization, Origin, X-Requested-With, Content-Type, Accept, User-Agent
access-control-allow-methods: OPTIONS, GET, DELETE, POST, PUT, HEAD, PATCH
access-control-allow-origin: *
content-type: application/json
server: api-gateway/1.9.3.1
x-content-type-options: nosniff
x-frame-options: deny
x-openwhisk-activation-id: 413a39b4c9ac4362ba39b4c9ac136270
x-request-id: Z20CrNPBMQHXBgLM8VcVSIOBTJIWL3Fo
x-xss-protection: 1; mode=block
x-backend-name: 3t7g8apsfQlFyvuHIQn9e8--F_AdobeRuntime
x-cdn-request-id: 55c2fa79-d2b6-457e-a2b7-80d5ab92f9dd
accept-ranges: bytes
accept-ranges: bytes
date: Sun, 09 Jun 2019 12:48:10 GMT
via: 1.1 varnish
x-served-by: cache-tyo19923-TYO
x-cache: MISS
x-cache-hits: 0
x-timer: S1560084490.956233,VS0,VE309
vary: X-Debug,X-Strain,X-Request-Type
strict-transport-security: max-age=31536000
x-version: 121; src=121; cli=1.0.0; rev=online
x-url: /client/README.html
x-backend-url: /api/v1/web/helix/63a0124113294dd2e23b3fe85f79f280946112a6/html?owner=adobe&repo=project-helix.io&ref=master&path=/client/README.md&selector=&extension=html&strain=foo&rootPath=&params=
x-strain: foo
x-github-static-ref: @(null)
x-fulldirname: /client
x-action-root: helix/63a0124113294dd2e23b3fe85f79f280946112a6
x-orig-url: /client/README.html
x-repo-root-path:
x-trace: vcl_recv; hlx_recv_init; hlx_strain(cookie); hlx_block_recv; hlx_deny; hlx_allow; hlx_request_type(none); hlx_type_pipeline; hlx_owner; hlx_repo; hlx_ref; hlx_root_path; hlx_action_root; vcl_hash(www.project-helix.io/client/README.html); hlx_bereq,vcl_miss(www.project-helix.io/client/README.html); vcl_fetch(400: /client/README.html); vcl_deliver; hlx_headers_deliver; hlx_deliver_errors; hlx_deliver_static
content-length: 100

{
  "code": "Z20CrNPBMQHXBgLM8VcVSIOBTJIWL3Fo",
  "error": "Response is not valid 'message/http'."
}

The activation on wsk shows:

    "statusCode": 0,
    "response": {
        "status": "application error",
        "statusCode": 0,
        "success": false,
        "result": {
            "error": "StatusCodeError: 404 - \"404: Not Found\\n\"\n    at new StatusCodeError (/nodejsAction/XXLBElAn/node_modules/request-promise-core/lib/errors.js:32:15)\n    at Request.plumbing.callback (/nodejsAction/XXLBElAn/node_modules/request-promise-core/lib/plumbing.js:104:33)\n    at Request.RP$callback [as _callback] (/nodejsAction/XXLBElAn/node_modules/request-promise-core/lib/plumbing.js:46:31)\n    at Request.self.callback (/node_modules/request/request.js:185:22)\n    at Request.emit (events.js:189:13)\n    at Request.<anonymous> (/node_modules/request/request.js:1161:10)\n    at Request.emit (events.js:189:13)\n    at IncomingMessage.<anonymous> (/node_modules/request/request.js:1083:12)\n    at Object.onceWrapper (events.js:277:13)\n    at IncomingMessage.emit (events.js:194:15)"
        }
    },

Expected behavior
The server should respond with a 404.

@trieloff WDYT?

[tripodsan]

see https://github.com/adobe/helix-publish/blob/8099974e205d344643d7ccf48688e644af66945d/layouts/fastly/helix.vcl#L159-L162

[tripodsan]

the problem here is not the strain cookie - it only manifests here, because the root path of the strain is wrong. the underlying problem is that fetch fails.

eg:

$ curl -s  https://www.project-helix.io/client/foobar.html
{
  "code": "eUFFqI3JpLOgayxtg1nqWeZANIvqciAj",
  "error": "Response is not valid 'message/http'."
}

[tripodsan]

running the action locally shows the correct response:

$ node
> const html = require('./html.js');
> html.main({repo:'helix-pipeline', owner:'adobe', path:'not-exists.md'}).then(console.log).catch(console.error);
...
debug: Constructing HTML Pipeline
debug: fetching Markdown from https://raw.githubusercontent.com/adobe/helix-pipeline/master/not-exists.md
error: Could not find Markdown at https://raw.githubusercontent.com/adobe/helix-pipeline/master/not-exists.md
{ statusCode: 404,
  headers: {},
  body: '',
  error:
   'StatusCodeError: 404 - "404: Not Found\\n"\n    at new StatusCodeError (/Users/tripod/codez/helix/sandbox/hlxtest/.hlx/build/html/node_modules/request-promise-core/lib/errors.js:32:15)\n    at Request.plumbing.callback 

maybe something changed on openwhisk?

[tripodsan]

apparently, when the error is not set on the return value, the response is correct.

eg:

function main(...params) {
  return {
    headers: { 'Content-Type': 'text/plain' },
    statusCode: 404,
    error: 'not found',
    body: '',
  };
}

vs:

function main(...params) {
  return {
    headers: { 'Content-Type': 'text/plain' },
    statusCode: 404,
    body: '',
  };
}

[tripodsan]

as @alexkli pointed out:

---

Once there is one error field, it not only sees it as application error, but also drops all the other fields and only records the error field in the activation result.
That error field can be an object though, and should have its string message in another nested error field:

  error: {
    error: "did not work",
    statusCode: 500
  }
}

This is useful if you want a human readable error message and some programmatic error information such as codes.

whether the activation is an error or not is your choice I guess. I agree, for webactions a 4xx or 5xx http response should usually be a success result, no need for an application error. was just pointing out the options.

---

so when we use:

function main(params) {
  return {
    error: {
      headers: { 'Content-Type': 'text/html', 'X-Foo': 'bar' },
      statusCode: 404,
      error: 'not found'
    },
  };
}

then the result is as expected:

$ curl -D -  https://adobeioruntime.net/api/v1/web/tripod/default/test
HTTP/1.1 404 Not Found
Access-Control-Allow-Headers: Authorization, Origin, X-Requested-With, Content-Type, Accept, User-Agent
Access-Control-Allow-Methods: OPTIONS, GET, DELETE, POST, PUT, HEAD, PATCH
Access-Control-Allow-Origin: *
Content-Type: text/plain
Date: Mon, 10 Jun 2019 23:39:35 GMT
Server: api-gateway/1.9.3.1
X-Content-Type-Options: nosniff
X-Foo: bar
X-Frame-Options: deny
x-openwhisk-activation-id: adcbc496c8134a818bc496c8134a8158
X-Request-ID: bRlskyxwqkZqEb3OzoccN7RkfJAy83hN
X-XSS-Protection: 1; mode=block
Content-Length: 0
Connection: keep-alive

with:

$ wsk activation get -s adcbc496c8134a818bc496c8134a8158
activation result for '/tripod/test' (application error at 2019-06-11 08:39:35 +0900 JST)
{
    "error": {
        "error": "not found",
        "headers": {
            "Content-Type": "text/html",
            "X-Foo": "bar"
        },
        "statusCode": 404
    }
}

However, I agree with @alexkli, that we should not treat expected errors as application errors.

[adobe-bot]

🎉 This issue has been resolved in version 3.2.2 🎉

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

Your semantic-release bot 📦🚀