Setting debug_mode with Measurement Protocol (GA4) - google-analytics

Question

Can't find a way to set the debug_mode parameter using Measurement Protocol 4.
Tried to put it everywhere (and naming it all i can think of) but without luck :)
Documentation is still very light and doesn't mention the debug_mode.
With web/js and GA4 it works fine!

Answer 1

Weird. Suddenly the debug mode started to work with code I'm 100% sure didn't work before.
Adding the parameter "debug_mode": true to the measurement protocol request will make it show up in Analytics' DebugView.
Sample json payload that works:
{
"client_id": "XXXXXXXXXX.YYYYYYYYYY",
"events": [
{
"name": "page_view",
"params": {
"page_location": "...",
"page_path": "...",
"page_title": "...",
"debug_mode": true
}
}
]
}

Answer 2

To add to the answers of #DalmTo and #bang - I wasn't seeing events I was sending over the Measurement Protocol show up in our GA4 Debug View. The root cause in my case was that the Measurement Protocol expects a funky format for the user_properties, but the following steps should help others debug other problems as well.
Steps I took to resolve:
Add the debug_mode: true field to individual event params as described in #bang's answer
Use the /debug/mp endpoint as described in #DalmTo's answer - this pointed me towards the errors in my user_properties format
Regarding the user_properties field, I was sending something along these lines:
{
"client_id": "XXX.XXX",
"user_id": "YYY",
"user_properties": {
"property_a": "value_a",
"property_b": "value_b"
},
"events": ...
}
Turns out GA4 / Measurement Protocol expect something like this:
{
"client_id": "XXX.XXX",
"user_id": "YYY",
"user_properties": {
"property_a": { "value": "value_a" },
"property_b": { "value": "value_b" }
},
"events": ...
}
At the time of writing, the only way to figure this out is to carefully check out the example here.

Answer 3

The measurment protocol for ga4 has two endpoints just like the measurment protocol for the old Google anlaytics
Measurement Protocol /mp/collect
Measurement Protocol Validation Server /debug/mp/collect
So if you send a event to it will be sent to Google anlaytics ga4
POST /mp/collect HTTP/1.1
HOST: www.google-analytics.com
<payload_data>
So if you send a event to it will be sent to debug endpoint for Google anlaytics ga4
POST /debug/mp/collect HTTP/1.1
HOST: www.google-analytics.com
<payload_data>