X-Appengine-Inbound-Appid header is not added in G

Question

According to https://cloud.google.com/appengine/docs/flexible/go/migrating#url_fetch ,in flexible environment we can use http lib instead of urlFetch which is supposed to add GAE related headers.

My app is in flexible environment but "X-Appengine-Inbound-Appid" is not set when it makes http request.

My app is in python using flask framework.

To test is the right headers got set, I'm making http request to the same app (different endpoint). But the inbound request doesn't have "X-Appengine-Inbound-Appid" in the headers. This is how I made http call:

@app.route('/ping')
def ping():
    res = requests.get("https://myapp.appspot.com/pong")
    print res.status_code
    return "ping"

@app.route('/pong')
def pong():
    print request.headers
    return "pong"

print request.headers shows that no "X-Appengine-Inbound-Appid" was set.

Anyone knows how to solve the issue? Thanks!

Answer 1

I did some research and created a case for GAE tech support's help.

Yes, this is indeed working as intended, this header is provided by the UrlFetch service, which isn't used on this case so there isn't a component to append this header.

Above is what I heard from GAE support. So... I believe "X-Appengine-Inbound-Appid" header for flex env is not available.