[SOLVED] GCP Cloud Function does not find Cloud Pub/Sub Topic

Hello everyone.

I know this is a GCP issue. But because it is indirectly related with ChirpStack, I am bringing it here. Maybe somebody more experienced with GCP might help me.

I was following this guide https://www.chirpstack.io/guides/google-cloud-platform/ to deploy ChirpStack in GCP. I am stuck on Create downlink Cloud Function.

The Cloud function fails on being deployed. This is the log:

Deployment failure:
indent preformatted text by 4 spaces
Build failed: go: finding google.golang.org/genproto v0.0.0-20190605220351-eb0b1bdb6ae6 
go: finding cloud.google.com/go v0.39.0 go: finding google.golang.org/genproto v0.0.0-20190508193815-b515fa19cec8 
go: finding google.golang.org/api v0.5.0 go: downloading cloud.google.com/go v0.39.0 
go: downloading google.golang.org/genproto v0.0.0-20190605220351-eb0b1bdb6ae6 
go: downloading google.golang.org/api v0.5.0 go: downloading google.golang.org/grpc v1.19.0 
go: downloading github.com/googleapis/gax-go/v2 v2.0.4 
go: downloading github.com/golang/protobuf v1.3.1 
go: downloading golang.org/x/net v0.0.0-20190311183353-d8887717615a 
go: downloading golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a 
go: downloading golang.org/x/text v0.3.1-0.20180807135948-17ff2d5776d2 
go: downloading golang.org/x/oauth2 v0.0.0-20190226205417-e64efc72b421 
go: downloading go.opencensus.io v0.21.0 
go: downloading github.com/hashicorp/golang-lru v0.5.0 
    # serverlessapp 
    ./worker.go:48:28: undefined: iotpubsub.HelloPubSub 
    ./worker.go:173:29: undefined: iotpubsub.HelloPubSub

When I re-edit the function, I can observe an error message: This selected message was not found in the list of topic projects.

Strange. As you can see, the topic is listed, but the function does not find it. I double-check in Pub/Sub, and it is there! I tried choosing from that list, and I also tried to create a topic. None of these attempts was successful.

I would appreciate any light here.

With regards

Sebastian

My mistake: I had omitted this specific instruction:

The Function to execute is called Send .

:man_facepalming: