1 pub mod api { 2 tonic::include_proto!("google.pubsub.v1"); 3 } 4 5 use api::{publisher_client::PublisherClient, ListTopicsRequest}; 6 use tonic::{ 7 metadata::MetadataValue, 8 transport::{Certificate, Channel, ClientTlsConfig}, 9 Request, 10 }; 11 12 const ENDPOINT: &str = "https://pubsub.googleapis.com"; 13 14 #[tokio::main] 15 async fn main() -> Result<(), Box<dyn std::error::Error>> { 16 let token = std::env::var("GCP_AUTH_TOKEN").map_err(|_| { 17 "Pass a valid 0Auth bearer token via `GCP_AUTH_TOKEN` environment variable.".to_string() 18 })?; 19 20 let project = std::env::args() 21 .nth(1) 22 .ok_or_else(|| "Expected a project name as the first argument.".to_string())?; 23 24 let bearer_token = format!("Bearer {}", token); 25 let header_value: MetadataValue<_> = bearer_token.parse()?; 26 27 let certs = tokio::fs::read("examples/data/gcp/roots.pem").await?; 28 29 let tls_config = ClientTlsConfig::new() 30 .ca_certificate(Certificate::from_pem(certs.as_slice())) 31 .domain_name("pubsub.googleapis.com"); 32 33 let channel = Channel::from_static(ENDPOINT) 34 .tls_config(tls_config)? 35 .connect() 36 .await?; 37 38 let mut service = PublisherClient::with_interceptor(channel, move |mut req: Request<()>| { 39 req.metadata_mut() 40 .insert("authorization", header_value.clone()); 41 Ok(req) 42 }); 43 44 let response = service 45 .list_topics(Request::new(ListTopicsRequest { 46 project: format!("projects/{0}", project), 47 page_size: 10, 48 ..Default::default() 49 })) 50 .await?; 51 52 println!("RESPONSE={:?}", response); 53 54 Ok(()) 55 } 56