Improve error message for when no credential providers are available

src/cargo/util/auth/mod.rs

@@ -99,6 +99,7 @@ fn credential_provider(config: &Config, sid: &SourceId) -> CargoResult<Vec<Vec<S
  .collect()
  })
  .unwrap_or_else(default_providers);
+ tracing::debug!(?global_providers);
 
  let providers = match cfg {
  // If there's a specific provider configured for this registry, use it.
@@ -442,6 +443,7 @@ fn credential_action(
  headers,
  };
  let providers = credential_provider(config, sid)?;
+ let mut any_not_found = false;
  for provider in providers {
  let args: Vec<&str> = provider
  .iter()
@@ -471,8 +473,8 @@ fn credential_action(
  })?;
  match provider.perform(&registry, &action, &args[1..]) {
  Ok(response) => return Ok(response),
- Err(cargo_credential::Error::UrlNotSupported)
- | Err(cargo_credential::Error::NotFound) => {}
+ Err(cargo_credential::Error::UrlNotSupported) => {}
+ Err(cargo_credential::Error::NotFound) => any_not_found = true,
  e => {
  return e.with_context(|| {
  format!(
@@ -483,7 +485,11 @@ fn credential_action(
  }
  }
  }
- Err(cargo_credential::Error::NotFound.into())
+ if any_not_found {
+ Err(cargo_credential::Error::NotFound.into())
+ } else {
+ anyhow::bail!("no credential providers could handle the request")
+ }
 }
 
 /// Returns the token to use for the given registry.

src/doc/src/reference/unstable.md

@@ -1068,7 +1068,14 @@ specified in the `registries` table:
 
 ```toml
 [registries.my-registry]
-global-credential-provider = "/usr/bin/cargo-creds"
+credential-provider = "/usr/bin/cargo-creds"
+```
+
+The credential provider for crates.io can be specified as:
+
+```toml
+[registry]
+credential-provider = "/usr/bin/cargo-creds"
 ```
 
 The value can be a string with spaces separating arguments or it can be a TOML

tests/testsuite/credential_process.rs

@@ -320,6 +320,86 @@ fn build_provider(name: &str, response: &str) -> String {
  toml_bin(&cred_proj, name)
 }
 
+#[cargo_test]
+fn all_not_found() {
+ let server = registry::RegistryBuilder::new()
+ .no_configure_token()
+ .auth_required()
+ .http_index()
+ .build();
+ let not_found = build_provider("not_found", r#"{"Err": {"kind": "not-found"}}"#);
+ cargo_util::paths::append(
+ &paths::home().join(".cargo/config"),
+ format!(
+ r#"
+ [registry]
+ global-credential-providers = ["not_found"]
+ [credential-alias]
+ not_found = ["{not_found}"]
+ "#,
+ )
+ .as_bytes(),
+ )
+ .unwrap();
+
+ cargo_process("install -v foo -Zcredential-process -Zregistry-auth")
+ .masquerade_as_nightly_cargo(&["credential-process", "registry-auth"])
+ .replace_crates_io(server.index_url())
+ .with_status(101)
+ .with_stderr(
+ r#"[UPDATING] [..]
+[CREDENTIAL] [..]not_found[..] get crates-io
+{"v":1,"registry":{"index-url":"[..]","name":"crates-io","headers":[[..]"WWW-Authenticate: Cargo login_url=\"https://test-registry-login/me\""[..]]},"kind":"get","operation":"read","args":[]}
+[ERROR] failed to query replaced source registry `crates-io`
+
+Caused by:
+ no token found, please run `cargo login`
+ or use environment variable CARGO_REGISTRY_TOKEN
+"#,
+ )
+ .run();
+}
+
+#[cargo_test]
+fn all_not_supported() {
+ let server = registry::RegistryBuilder::new()
+ .no_configure_token()
+ .auth_required()
+ .http_index()
+ .build();
+ let not_supported =
+ build_provider("not_supported", r#"{"Err": {"kind": "url-not-supported"}}"#);
+ cargo_util::paths::append(
+ &paths::home().join(".cargo/config"),
+ format!(
+ r#"
+ [registry]
+ global-credential-providers = ["not_supported"]
+ [credential-alias]
+ not_supported = ["{not_supported}"]
+ "#,
+ )
+ .as_bytes(),
+ )
+ .unwrap();
+
+ cargo_process("install -v foo -Zcredential-process -Zregistry-auth")
+ .masquerade_as_nightly_cargo(&["credential-process", "registry-auth"])
+ .replace_crates_io(server.index_url())
+ .with_status(101)
+ .with_stderr(
+ r#"[UPDATING] [..]
+[CREDENTIAL] [..]not_supported[..] get crates-io
+{"v":1,"registry":{"index-url":"[..]","name":"crates-io","headers":[[..]"WWW-Authenticate: Cargo login_url=\"https://test-registry-login/me\""[..]]},"kind":"get","operation":"read","args":[]}
+[ERROR] failed to query replaced source registry `crates-io`
+
+Caused by:
+ no credential providers could handle the request
+"#,
+ )
+ .run();
+}
+
 #[cargo_test]
 fn multiple_providers() {
  let server = registry::RegistryBuilder::new()