path variables and blobs

[lpw]

Any pointers to the best way to handle a POST of a blob body to a url with path variables (/channel/timestamp)?

I'm not sure how to express that input as the path variables, such as channel and timestamp, are named, but the body isn't:

input: z.object({
  channel: z
    .string()
    .describe("channel string"),
  timestamp: z
    .number()
    .nonnegative()
    .describe("epoch timestamp"),
  body?: z.instanceof( Blob ),

I've read the docs, but I'm still not getting it - sorry if the answer to this is obvious and I'm just missing it.

[RobinTail]

Hello @lpw

Path params (which I presume you meant by "variables"), should be specified with : symbol in path for Express:

/:channel/:timestamp

Therefore, the Routing object should look this way:

const routing: Routing = {
  ":channel": {
    ":timestamp": theEndpoint
  }
};

See https://ez.robintail.cz/v27.0.1/routing for more examples.

Regarding the Blob instance — i'm not sure, because the input schema validates against the already parsed request properties combined. There is no body itself by default and Endpoints have no access to original request (by default).

However, if you use the ez.raw() schema as the input (and you're using the createServer() approach), the body would be parsed by express.raw(), and you can get the raw body as a Buffer, which I suppose can be converted into a Blob somehow.
See https://ez.robintail.cz/v27.0.1/accepting-raw-data for details.

See also rawParser option in config to customize such parsing. I hope it helps.

[lpw]

Hi, and thanks for the quick reply!

Yes, indeed my routing is setup with :channel and :timestamp, and I'm indeed using the createServer() approach (as in the example).

But I seem to be having a general problem posting raw blobs or buffers. I'm now running the just the example code which has an endpoint /v1/avatar/raw routed to the rawAcceptingEndpoint function (using ez.raw()) in your link and example. When I post a binary raw blob to /v1/avatar/raw the response is {"status":"error","error":{"message":"raw: Expected Buffer"}}. I'm posting various raw blob content-types, such as audio/webm, image/jpeg, image/png, video/mp4, but all are rejected as not being buffers.

But this is working when I post blobs via curl - I need to understand what's different about my client (sorry for the distraction)...

[RobinTail]

But this is working when I post blobs via curl

@lpw , perhaps it's due to the content type of your request.

Try application/octet-stream, similar to this test:

express-zod-api/example/index.spec.ts

Line 260 in 7f11493

headers: { "Content-Type": "application/octet-stream" },

That MIME type is the default one that express.raw() would process, see:
https://expressjs.com/en/5x/api.html#express.raw

audio/webm, image/jpeg, image/png, video/mp4

In order to adjust it to process others, you'd need to set rawParser option in your config with something like

express.raw({ type: ["audio/*", "image/*", "video/*" ] })

[lpw]

I just tried that, coincidentally. after inspecting the headers in the curl command, was about to delete or edit my previous reply...

application/octet-stream made the difference, and works - thanks!

I don't think I need to add the other parsing formats, but thanks for the pointers and contexts.

With that problem out of the way, this is working great:

  input: ez.raw({
    channel: z
      .string()
      .describe( 'channel string' ),
    timestamp: z
      // .number()
      // .nonnegative()
      .string()
      .regex( /\d+/ )
      .transform( id => parseInt( id, 10 ) )
      .describe( 'epoch timestamp' ),
  }),

Perhaps path params are inherently strings, but with regex and transform make this framework so versatile, not a problem.

Thanks so much again for such prompt and helpful replies!