emitter.send() drops datacontenttype header

[c-pius]

Not entirely sure on this but I think emitter.send() drops the datacontenttype header.

structured

const event = new CloudEvent({
    id: "4711",
    type: "foo",
    source: "bar",
    datacontenttype: "text/xml",
    data: "<xml>test</xml>"
});

emitter.send(event, { mode: "structured" }).then((response) => {
    console.log(`status: ${response.status} ${response.statusText}`)
}).catch(console.error)

received content-type header : "application/cloudevents+json"

received payload:

{
    "data": "<xml>test</xml>",
    "specversion": "1.0",
    "id": "4711",
    "time": "2020-07-06T06:56:01.645Z",
    "source": "bar",
    "type": "foo"
}

binary

const event = new CloudEvent({
    id: "4711",
    type: "foo",
    source: "bar",
    datacontenttype: "text/xml",
    data: "<xml>test</xml>"
});

emitter.send(event, { mode: "binary" }).then((response) => {
    console.log(`status: ${response.status} ${response.statusText}`)
}).catch(console.error)

received content-type header = "application/json"

I assume the datacontenttype is dropped (not allowed in binary binding). But then the missing value is defaulted to application/json for the content-type header (seems correct from the spec). However, the content-type header should be set to "text/xml" from the given datacontenttype value.

[lance]

For binary mode, the ce-datacontenttype header MUST NOT be present in the message. But you are correct that the content-type header should be text/xml in this case.

For structured mode, the received payload should have the datacontenttype property.

Thanks for reporting this.

[lance]

I have been testing the binary mode transmission, and realized that you need to use dataContentType. If you do, your scenario should work. Still poking structured mode.

[lance]

@c-pius the module is working as expected for both binary and structured events. In both cases, the property on the CloudEvent object is dataContentType. I'm going to close this as not-a-bug. If you find additional problems please feel free to reopen or create a new issue.

[c-pius]

ah okay, sorry for the confusion. Will this change with the new release however? I was looking at the examples and that is actually where I got the all lowercase datacontenttype from

sdk-javascript/examples/typescript-ex/src/index.ts

Line 9 in 51035dc

datacontenttype: "text/plain",

[lance]

@c-pius yes - the examples are previewing what will be coming in 3.0.0. You can track the release of that in this issue. We made this change to simplify marshaling/unmarshaling of CloudEvent objects, since the specification requires event attributes to be in all lowercase.