Make the optional configuration sections really optional

crates/cli/src/commands/database.rs

@@ -17,7 +17,7 @@ use std::process::ExitCode;
 use anyhow::Context;
 use clap::Parser;
 use figment::Figment;
-use mas_config::{ConfigurationSection, DatabaseConfig};
+use mas_config::{ConfigurationSectionExt, DatabaseConfig};
 use mas_storage_pg::MIGRATOR;
 use tracing::{info_span, Instrument};
 
@@ -38,7 +38,7 @@ enum Subcommand {
 impl Options {
     pub async fn run(self, figment: &Figment) -> anyhow::Result<ExitCode> {
         let _span = info_span!("cli.database.migrate").entered();
-        let config = DatabaseConfig::extract(figment)?;
+        let config = DatabaseConfig::extract_or_default(figment)?;
         let mut conn = database_connection_from_config(&config).await?;
 
         // Run pending migrations

crates/cli/src/commands/debug.rs

@@ -18,7 +18,7 @@ use clap::Parser;
 use figment::Figment;
 use http_body_util::BodyExt;
 use hyper::{Response, Uri};
-use mas_config::{ConfigurationSection, PolicyConfig};
+use mas_config::{ConfigurationSectionExt, PolicyConfig};
 use mas_handlers::HttpClientFactory;
 use mas_http::HttpServiceExt;
 use tokio::io::AsyncWriteExt;
@@ -124,7 +124,7 @@ impl Options {
 
             SC::Policy => {
                 let _span = info_span!("cli.debug.policy").entered();
-                let config = PolicyConfig::extract(figment)?;
+                let config = PolicyConfig::extract_or_default(figment)?;
                 info!("Loading and compiling the policy module");
                 let policy_factory = policy_factory_from_config(&config).await?;
 

crates/cli/src/commands/manage.rs

@@ -19,7 +19,9 @@ use clap::{ArgAction, CommandFactory, Parser};
 use console::{pad_str, style, Alignment, Style, Term};
 use dialoguer::{theme::ColorfulTheme, Confirm, FuzzySelect, Input, Password};
 use figment::Figment;
-use mas_config::{ConfigurationSection, DatabaseConfig, MatrixConfig, PasswordsConfig};
+use mas_config::{
+    ConfigurationSection, ConfigurationSectionExt, DatabaseConfig, MatrixConfig, PasswordsConfig,
+};
 use mas_data_model::{Device, TokenType, Ulid, UpstreamOAuthProvider, User};
 use mas_email::Address;
 use mas_handlers::HttpClientFactory;
@@ -192,8 +194,8 @@ impl Options {
                 let _span =
                     info_span!("cli.manage.set_password", user.username = %username).entered();
 
-                let database_config = DatabaseConfig::extract(figment)?;
+                let database_config = DatabaseConfig::extract_or_default(figment)?;
-                let passwords_config = PasswordsConfig::extract(figment)?;
+                let passwords_config = PasswordsConfig::extract_or_default(figment)?;
 
                 let mut conn = database_connection_from_config(&database_config).await?;
                 let password_manager = password_manager_from_config(&passwords_config).await?;
@@ -233,7 +235,7 @@ impl Options {
                 )
                 .entered();
 
-                let database_config = DatabaseConfig::extract(figment)?;
+                let database_config = DatabaseConfig::extract_or_default(figment)?;
                 let mut conn = database_connection_from_config(&database_config).await?;
                 let txn = conn.begin().await?;
                 let mut repo = PgRepository::from_conn(txn);
@@ -267,7 +269,7 @@ impl Options {
                 admin,
                 device_id,
             } => {
-                let database_config = DatabaseConfig::extract(figment)?;
+                let database_config = DatabaseConfig::extract_or_default(figment)?;
                 let mut conn = database_connection_from_config(&database_config).await?;
                 let txn = conn.begin().await?;
                 let mut repo = PgRepository::from_conn(txn);
@@ -312,7 +314,7 @@ impl Options {
 
             SC::ProvisionAllUsers => {
                 let _span = info_span!("cli.manage.provision_all_users").entered();
-                let database_config = DatabaseConfig::extract(figment)?;
+                let database_config = DatabaseConfig::extract_or_default(figment)?;
                 let mut conn = database_connection_from_config(&database_config).await?;
                 let mut txn = conn.begin().await?;
 
@@ -338,7 +340,7 @@ impl Options {
             SC::KillSessions { username, dry_run } => {
                 let _span =
                     info_span!("cli.manage.kill_sessions", user.username = username).entered();
-                let database_config = DatabaseConfig::extract(figment)?;
+                let database_config = DatabaseConfig::extract_or_default(figment)?;
                 let mut conn = database_connection_from_config(&database_config).await?;
                 let txn = conn.begin().await?;
                 let mut repo = PgRepository::from_conn(txn);
@@ -408,7 +410,7 @@ impl Options {
                 deactivate,
             } => {
                 let _span = info_span!("cli.manage.lock_user", user.username = username).entered();
-                let config = DatabaseConfig::extract(figment)?;
+                let config = DatabaseConfig::extract_or_default(figment)?;
                 let mut conn = database_connection_from_config(&config).await?;
                 let txn = conn.begin().await?;
                 let mut repo = PgRepository::from_conn(txn);
@@ -440,7 +442,7 @@ impl Options {
 
             SC::UnlockUser { username } => {
                 let _span = info_span!("cli.manage.lock_user", user.username = username).entered();
-                let config = DatabaseConfig::extract(figment)?;
+                let config = DatabaseConfig::extract_or_default(figment)?;
                 let mut conn = database_connection_from_config(&config).await?;
                 let txn = conn.begin().await?;
                 let mut repo = PgRepository::from_conn(txn);
@@ -473,8 +475,8 @@ impl Options {
                 ignore_password_complexity,
             } => {
                 let http_client_factory = HttpClientFactory::new();
-                let password_config = PasswordsConfig::extract(figment)?;
+                let password_config = PasswordsConfig::extract_or_default(figment)?;
-                let database_config = DatabaseConfig::extract(figment)?;
+                let database_config = DatabaseConfig::extract_or_default(figment)?;
                 let matrix_config = MatrixConfig::extract(figment)?;
 
                 let password_manager = password_manager_from_config(&password_config).await?;

crates/cli/src/commands/server.rs

@@ -18,7 +18,9 @@ use anyhow::Context;
 use clap::Parser;
 use figment::Figment;
 use itertools::Itertools;
-use mas_config::{AppConfig, ClientsConfig, ConfigurationSection, UpstreamOAuth2Config};
+use mas_config::{
+    AppConfig, ClientsConfig, ConfigurationSection, ConfigurationSectionExt, UpstreamOAuth2Config,
+};
 use mas_handlers::{ActivityTracker, CookieManager, HttpClientFactory, Limiter, MetadataCache};
 use mas_listener::{server::Server, shutdown::ShutdownStream};
 use mas_matrix_synapse::SynapseConnection;
@@ -103,8 +105,8 @@ impl Options {
         } else {
             // Sync the configuration with the database
             let mut conn = pool.acquire().await?;
-            let clients_config = ClientsConfig::extract(figment)?;
+            let clients_config = ClientsConfig::extract_or_default(figment)?;
-            let upstream_oauth2_config = UpstreamOAuth2Config::extract(figment)?;
+            let upstream_oauth2_config = UpstreamOAuth2Config::extract_or_default(figment)?;
 
             crate::sync::config_sync(
                 upstream_oauth2_config,

crates/cli/src/commands/templates.rs

@@ -17,8 +17,8 @@ use std::process::ExitCode;
 use clap::Parser;
 use figment::Figment;
 use mas_config::{
-    AccountConfig, BrandingConfig, CaptchaConfig, ConfigurationSection, ExperimentalConfig,
+    AccountConfig, BrandingConfig, CaptchaConfig, ConfigurationSection, ConfigurationSectionExt,
-    MatrixConfig, PasswordsConfig, TemplatesConfig,
+    ExperimentalConfig, MatrixConfig, PasswordsConfig, TemplatesConfig,
 };
 use mas_storage::{Clock, SystemClock};
 use rand::SeedableRng;
@@ -45,13 +45,13 @@ impl Options {
             SC::Check => {
                 let _span = info_span!("cli.templates.check").entered();
 
-                let template_config = TemplatesConfig::extract(figment)?;
+                let template_config = TemplatesConfig::extract_or_default(figment)?;
-                let branding_config = BrandingConfig::extract(figment)?;
+                let branding_config = BrandingConfig::extract_or_default(figment)?;
                 let matrix_config = MatrixConfig::extract(figment)?;
-                let experimental_config = ExperimentalConfig::extract(figment)?;
+                let experimental_config = ExperimentalConfig::extract_or_default(figment)?;
-                let password_config = PasswordsConfig::extract(figment)?;
+                let password_config = PasswordsConfig::extract_or_default(figment)?;
-                let account_config = AccountConfig::extract(figment)?;
+                let account_config = AccountConfig::extract_or_default(figment)?;
-                let captcha_config = CaptchaConfig::extract(figment)?;
+                let captcha_config = CaptchaConfig::extract_or_default(figment)?;
 
                 let clock = SystemClock::default();
                 // XXX: we should disallow SeedableRng::from_entropy

crates/config/src/lib.rs

@@ -26,4 +26,7 @@ pub(crate) mod schema;
 mod sections;
 pub(crate) mod util;
 
-pub use self::{sections::*, util::ConfigurationSection};
+pub use self::{
+    sections::*,
+    util::{ConfigurationSection, ConfigurationSectionExt},
+};

crates/config/src/util.rs

@@ -46,3 +46,32 @@ pub trait ConfigurationSection: Sized + DeserializeOwned {
         Ok(this)
     }
 }
+
+/// Extension trait for [`ConfigurationSection`] to allow extracting the
+/// configuration section from a [`Figment`] or return the default value if the
+/// section is not present.
+pub trait ConfigurationSectionExt: ConfigurationSection + Default {
+    /// Extract the configuration section from the given [`Figment`], or return
+    /// the default value if the section is not present.
+    ///
+    /// # Errors
+    ///
+    /// Returns an error if the configuration section is invalid.
+    fn extract_or_default(figment: &Figment) -> Result<Self, figment::Error> {
+        let this: Self = if let Some(path) = Self::PATH {
+            // If the configuration section is not present, we return the default value
+            if !figment.contains(path) {
+                return Ok(Self::default());
+            }
+
+            figment.extract_inner(path)?
+        } else {
+            figment.extract()?
+        };
+
+        this.validate(figment)?;
+        Ok(this)
+    }
+}
+
+impl<T: ConfigurationSection + Default> ConfigurationSectionExt for T {}