change content-type of performance tests to application/json

[capri-xiyue]

Fixes #2009

Proposed Changes

• change content-type of performance tests to application/json

Release Note

None

[capri-xiyue]

/assign @grantr

[chizhg]

/retest

[slinkydeveloper]

@capri-xiyue why this change?

[slinkydeveloper]

If you want to change the content type to application/json, then you must quote the body string to make the json valid. An unquoted string is not a valid application/json body

[capri-xiyue]

/retest

[capri-xiyue]

@capri-xiyue why this change?

FYI #2009. Currently cloudevents sdk doesn't support Content-type "text/plain"

[capri-xiyue]

If you want to change the content type to application/json, then you must quote the body string to make the json valid. An unquoted string is not a valid application/json body

@slinkydeveloper, this is how the performance test sends cloudevents
`func (cet CloudEventsTargeter) VegetaTargeter() vegeta.Targeter {
return func(t *vegeta.Target) error {
t.Method = http.MethodPost
t.URL = cet.sinkUrl

	t.Header = make(http.Header)

	t.Header.Set("Ce-Id", uuid.New().String())
	t.Header.Set("Ce-Type", cet.eventType)
	t.Header.Set("Ce-Source", cet.eventSource)
	t.Header.Set("Ce-Specversion", "0.2")

	t.Header.Set("Content-Type", "application/json")

	t.Body = []byte(generateRandString(cet.msgSize))

	return nil
}

}`
What do you mean by "you must quote the body string to make the json valid"? I thought the packge vegeta shoud be able to handle this.

[capri-xiyue]

/assign @grantr

[slinkydeveloper]

FYI #2009. Currently cloudevents sdk doesn't support Content-type "text/plain"

The reason I avoided json is to avoid the additional parsing step the receiver does when it receives the message. Maybe can we use a binary format like application/octet-stream to avoid parsing at all?

[slinkydeveloper]

If you want to change the content type to application/json, then you must quote the body string to make the json valid. An unquoted string is not a valid application/json body

@slinkydeveloper, this is how the performance test sends cloudevents
`func (cet CloudEventsTargeter) VegetaTargeter() vegeta.Targeter {
return func(t *vegeta.Target) error {
t.Method = http.MethodPost
t.URL = cet.sinkUrl

	t.Header = make(http.Header)

	t.Header.Set("Ce-Id", uuid.New().String())
	t.Header.Set("Ce-Type", cet.eventType)
	t.Header.Set("Ce-Source", cet.eventSource)
	t.Header.Set("Ce-Specversion", "0.2")

	t.Header.Set("Content-Type", "application/json")

	t.Body = []byte(generateRandString(cet.msgSize))

	return nil
}

}`
What do you mean by "you must quote the body string to make the json valid"? I thought the packge vegeta shoud be able to handle this.

This one:

t.Body = []byte(generateRandString(cet.msgSize))

Should be:

t.Body = []byte("\"" + generateRandString(cet.msgSize) + "\"")

[capri-xiyue]

FYI #2009. Currently cloudevents sdk doesn't support Content-type "text/plain"

The reason I avoided json is to avoid the additional parsing step the receiver does when it receives the message. Maybe can we use a binary format like application/octet-stream to avoid parsing at all?

@slinkydeveloper Currently cloudevents sdk-go only supports only supports type as follows:
"", "application/json" and "text/json" and "application/xml" and "text/xml".
application/octet-stream is not supported by cloudevents sdk-go. I've already created cloudevents/sdk-go#232 to further track the Content-type support issues in cloudevents sdk-go.

[grantr]

The request body should be valid given the content-type, so we should add the quotes. When cloudevents/sdk-go#232 is fixed we can change the content-type back.

[grantr]

/lgtm

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