calculate the redirect_url for web oauth too

a bit more complicated because it needs to use the configured
public_address, etc

4 files changed, 37 insertions, 21 deletions

diff --git a/README.md b/README.md
index 4bdf079..66ed19a 100644
--- a/README.md
+++ b/README.md
@@ -169,9 +169,6 @@ need to configure separate OAuth applications for `cli` and `web` since the
     * OAuth client id. Required.
 * `client_secret`
     * OAuth client secret. Required.
-* `redirect_url`
-    * OAuth client redirect url. Required if `<client>` is `web`, and must be
-      the `/oauth` path at the externally reachable domain of your web server.
 
 #### `[client]` (used by `tt stream` and `tt watch`)
 
@@ -213,6 +210,20 @@ need to configure separate OAuth applications for `cli` and `web` since the
     * Name of the TTYrec file to save to or read from.
     * Default: `teleterm.ttyrec`
 
+### OAuth
+
+`tt` expects OAuth applications to be configured with specific values for the
+`redirect_url` setting. In particular:
+
+* For `cli`, the `redirect_url` should be exactly
+  `http://localhost:44141/oauth`.
+* For `web`, the `redirect_url` should be
+  `<scheme>://<public_address>/oauth/<method>`, where `<scheme>` is either
+  `http` or `https` depending on whether your web server has TLS enabled,
+  `<public_address>` is the `public_address` value configured in the `[web]`
+  section, and `<method>` is the authentication method (currently only
+  `recurse_center` is supported here).
+
 ## Troubleshooting
 
 ### I'm trying to watch someone and the output is a garbled mess!
diff --git a/teleterm/src/cmd/web.rs b/teleterm/src/cmd/web.rs
index 889179b..a9dc830 100644
--- a/teleterm/src/cmd/web.rs
+++ b/teleterm/src/cmd/web.rs
@@ -38,9 +38,20 @@ impl crate::config::Config for Config {
             self.oauth_configs
                 .iter()
                 .filter_map(|(ty, configs)| {
-                    configs
-                        .get(&crate::protocol::AuthClient::Web)
-                        .map(|config| (*ty, config.clone()))
+                    configs.get(&crate::protocol::AuthClient::Web).map(
+                        |config| {
+                            let mut config = config.clone();
+                            // TODO: tls
+                            let url = url::Url::parse(&format!(
+                                "http://{}/oauth/{}",
+                                self.web.public_address,
+                                ty.name()
+                            ))
+                            .unwrap();
+                            config.set_redirect_url(url);
+                            (*ty, config)
+                        },
+                    )
                 })
                 .collect(),
         ))
diff --git a/teleterm/src/config.rs b/teleterm/src/config.rs
index 4000cb7..95d5366 100644
--- a/teleterm/src/config.rs
+++ b/teleterm/src/config.rs
@@ -913,22 +913,12 @@ where
                             auth_client,
                         })
                         .map_err(serde::de::Error::custom)?;
+                    // this is wrong for Web configs, but it gets fixed up
+                    // later since we need to calculate the real value from
+                    // other parts of the config
                     let redirect_url =
-                        if auth_client == crate::protocol::AuthClient::Cli {
-                            url::Url::parse(crate::oauth::CLI_REDIRECT_URL)
-                                .unwrap()
-                        } else {
-                            config
-                                .redirect_url
-                                .context(
-                                    crate::error::OauthMissingConfiguration {
-                                        field: "redirect_url",
-                                        auth_type,
-                                        auth_client,
-                                    },
-                                )
-                                .map_err(serde::de::Error::custom)?
-                        };
+                        url::Url::parse(crate::oauth::CLI_REDIRECT_URL)
+                            .unwrap();
                     crate::oauth::RecurseCenter::config(
                         &client_id,
                         &client_secret,
diff --git a/teleterm/src/oauth.rs b/teleterm/src/oauth.rs
index 5283957..4e4ad72 100644
--- a/teleterm/src/oauth.rs
+++ b/teleterm/src/oauth.rs
@@ -145,6 +145,10 @@ pub struct Config {
 }
 
 impl Config {
+    pub fn set_redirect_url(&mut self, url: url::Url) {
+        self.redirect_url = url;
+    }
+
     fn into_basic_client(self) -> oauth2::basic::BasicClient {
         oauth2::basic::BasicClient::new(
             oauth2::ClientId::new(self.client_id),