feat: add to_url_lossy to connect options (#2902)

* feat: add get_url to connect options

Add a get_url to connect options and implement it for all needed types;
include get_filename for sqlite. These changes make it easier to test
sqlx.

* refactor: use expect with message

* refactor: change method name to `to_url_lossy`

* fix: remove unused imports

Author: lily-mosquitoes

sqlx-core/src/any/options.rs

@@ -43,6 +43,10 @@ impl ConnectOptions for AnyConnectOptions {
         })
     }
 
+    fn to_url_lossy(&self) -> Url {
+        self.database_url.clone()
+    }
+
     #[inline]
     fn connect(&self) -> BoxFuture<'_, Result<AnyConnection, Error>> {
         AnyConnection::connect(self)

sqlx-core/src/connection.rs

@@ -189,6 +189,35 @@ pub trait ConnectOptions: 'static + Send + Sync + FromStr<Err = Error> + Debug +
     /// Parse the `ConnectOptions` from a URL.
     fn from_url(url: &Url) -> Result<Self, Error>;
 
+    /// Get a connection URL that may be used to connect to the same database as this `ConnectOptions`.
+    ///
+    /// ### Note: Lossy
+    /// Any flags or settings which do not have a representation in the URL format will be lost.
+    /// They will fall back to their default settings when the URL is parsed.
+    ///
+    /// The only settings guaranteed to be preserved are:
+    /// * Username
+    /// * Password
+    /// * Hostname
+    /// * Port
+    /// * Database name
+    /// * Unix socket or SQLite database file path
+    /// * SSL mode (if applicable)
+    /// * SSL CA certificate path
+    /// * SSL client certificate path
+    /// * SSL client key path
+    ///
+    /// Additional settings are driver-specific. Refer to the source of a given implementation
+    /// to see which options are preserved in the URL.
+    ///
+    /// ### Panics
+    /// This defaults to `unimplemented!()`.
+    ///
+    /// Individual drivers should override this to implement the intended behavior.
+    fn to_url_lossy(&self) -> Url {
+        unimplemented!()
+    }
+
     /// Establish a new database connection with the options specified by `self`.
     fn connect(&self) -> BoxFuture<'_, Result<Self::Connection, Error>>
     where

sqlx-mysql/src/options/connect.rs

@@ -14,6 +14,10 @@ impl ConnectOptions for MySqlConnectOptions {
         Self::parse_from_url(url)
     }
 
+    fn to_url_lossy(&self) -> Url {
+        self.build_url()
+    }
+
     fn connect(&self) -> BoxFuture<'_, Result<Self::Connection, Error>>
     where
         Self::Connection: Sized,

sqlx-mysql/src/options/parse.rs

@@ -1,9 +1,9 @@
 use std::str::FromStr;
 
-use percent_encoding::percent_decode_str;
+use percent_encoding::{percent_decode_str, utf8_percent_encode, NON_ALPHANUMERIC};
 use sqlx_core::Url;
 
-use crate::error::Error;
+use crate::{error::Error, MySqlSslMode};
 
 use super::MySqlConnectOptions;
 
@@ -78,6 +78,65 @@ impl MySqlConnectOptions {
 
         Ok(options)
     }
+
+    pub(crate) fn build_url(&self) -> Url {
+        let mut url = Url::parse(&format!(
+            "mysql://{}@{}:{}",
+            self.username, self.host, self.port
+        ))
+        .expect("BUG: generated un-parseable URL");
+
+        if let Some(password) = &self.password {
+            let password = utf8_percent_encode(&password, NON_ALPHANUMERIC).to_string();
+            let _ = url.set_password(Some(&password));
+        }
+
+        if let Some(database) = &self.database {
+            url.set_path(&database);
+        }
+
+        let ssl_mode = match self.ssl_mode {
+            MySqlSslMode::Disabled => "DISABLED",
+            MySqlSslMode::Preferred => "PREFERRED",
+            MySqlSslMode::Required => "REQUIRED",
+            MySqlSslMode::VerifyCa => "VERIFY_CA",
+            MySqlSslMode::VerifyIdentity => "VERIFY_IDENTITY",
+        };
+        url.query_pairs_mut().append_pair("ssl-mode", ssl_mode);
+
+        if let Some(ssl_ca) = &self.ssl_ca {
+            url.query_pairs_mut()
+                .append_pair("ssl-ca", &ssl_ca.to_string());
+        }
+
+        url.query_pairs_mut().append_pair("charset", &self.charset);
+
+        if let Some(collation) = &self.collation {
+            url.query_pairs_mut().append_pair("charset", &collation);
+        }
+
+        if let Some(ssl_client_cert) = &self.ssl_client_cert {
+            url.query_pairs_mut()
+                .append_pair("ssl-cert", &ssl_client_cert.to_string());
+        }
+
+        if let Some(ssl_client_key) = &self.ssl_client_key {
+            url.query_pairs_mut()
+                .append_pair("ssl-key", &ssl_client_key.to_string());
+        }
+
+        url.query_pairs_mut().append_pair(
+            "statement-cache-capacity",
+            &self.statement_cache_capacity.to_string(),
+        );
+
+        if let Some(socket) = &self.socket {
+            url.query_pairs_mut()
+                .append_pair("socket", &socket.to_string_lossy());
+        }
+
+        url
+    }
 }
 
 impl FromStr for MySqlConnectOptions {
@@ -104,3 +163,16 @@ fn it_parses_password_with_non_ascii_chars_correctly() {
 
     assert_eq!(Some("p@ssw0rd".into()), opts.password);
 }
+
+#[test]
+fn it_returns_the_parsed_url() {
+    let url = "mysql://username:p@ssw0rd@hostname:3306/database";
+    let opts = MySqlConnectOptions::from_str(url).unwrap();
+
+    let mut expected_url = Url::parse(url).unwrap();
+    // MySqlConnectOptions defaults
+    let query_string = "ssl-mode=PREFERRED&charset=utf8mb4&statement-cache-capacity=100";
+    expected_url.set_query(Some(query_string));
+
+    assert_eq!(expected_url, opts.build_url());
+}

sqlx-postgres/src/options/connect.rs

@@ -13,6 +13,10 @@ impl ConnectOptions for PgConnectOptions {
         Self::parse_from_url(url)
     }
 
+    fn to_url_lossy(&self) -> Url {
+        self.build_url()
+    }
+
     fn connect(&self) -> BoxFuture<'_, Result<Self::Connection, Error>>
     where
         Self::Connection: Sized,

sqlx-postgres/src/options/parse.rs

@@ -1,6 +1,6 @@
 use crate::error::Error;
-use crate::PgConnectOptions;
-use sqlx_core::percent_encoding::percent_decode_str;
+use crate::{PgConnectOptions, PgSslMode};
+use sqlx_core::percent_encoding::{percent_decode_str, utf8_percent_encode, NON_ALPHANUMERIC};
 use sqlx_core::Url;
 use std::net::IpAddr;
 use std::str::FromStr;
@@ -108,6 +108,62 @@ impl PgConnectOptions {
 
         Ok(options)
     }
+
+    pub(crate) fn build_url(&self) -> Url {
+        let host = match &self.socket {
+            Some(socket) => {
+                utf8_percent_encode(&*socket.to_string_lossy(), NON_ALPHANUMERIC).to_string()
+            }
+            None => self.host.to_owned(),
+        };
+
+        let mut url = Url::parse(&format!(
+            "postgres://{}@{}:{}",
+            self.username, host, self.port
+        ))
+        .expect("BUG: generated un-parseable URL");
+
+        if let Some(password) = &self.password {
+            let password = utf8_percent_encode(&password, NON_ALPHANUMERIC).to_string();
+            let _ = url.set_password(Some(&password));
+        }
+
+        if let Some(database) = &self.database {
+            url.set_path(&database);
+        }
+
+        let ssl_mode = match self.ssl_mode {
+            PgSslMode::Allow => "ALLOW",
+            PgSslMode::Disable => "DISABLED",
+            PgSslMode::Prefer => "PREFERRED",
+            PgSslMode::Require => "REQUIRED",
+            PgSslMode::VerifyCa => "VERIFY_CA",
+            PgSslMode::VerifyFull => "VERIFY_FULL",
+        };
+        url.query_pairs_mut().append_pair("ssl-mode", ssl_mode);
+
+        if let Some(ssl_root_cert) = &self.ssl_root_cert {
+            url.query_pairs_mut()
+                .append_pair("ssl-root-cert", &ssl_root_cert.to_string());
+        }
+
+        if let Some(ssl_client_cert) = &self.ssl_client_cert {
+            url.query_pairs_mut()
+                .append_pair("ssl-cert", &ssl_client_cert.to_string());
+        }
+
+        if let Some(ssl_client_key) = &self.ssl_client_key {
+            url.query_pairs_mut()
+                .append_pair("ssl-key", &ssl_client_key.to_string());
+        }
+
+        url.query_pairs_mut().append_pair(
+            "statement-cache-capacity",
+            &self.statement_cache_capacity.to_string(),
+        );
+
+        url
+    }
 }
 
 impl FromStr for PgConnectOptions {
@@ -242,3 +298,31 @@ fn it_parses_sqlx_options_correctly() {
         opts.options
     );
 }
+
+#[test]
+fn it_returns_the_parsed_url_when_socket() {
+    let url = "postgres://username@%2Fvar%2Flib%2Fpostgres/database";
+    let opts = PgConnectOptions::from_str(url).unwrap();
+
+    let mut expected_url = Url::parse(url).unwrap();
+    // PgConnectOptions defaults
+    let query_string = "ssl-mode=PREFERRED&statement-cache-capacity=100";
+    let port = 5432;
+    expected_url.set_query(Some(query_string));
+    let _ = expected_url.set_port(Some(port));
+
+    assert_eq!(expected_url, opts.build_url());
+}
+
+#[test]
+fn it_returns_the_parsed_url_when_host() {
+    let url = "postgres://username:p@ssw0rd@hostname:5432/database";
+    let opts = PgConnectOptions::from_str(url).unwrap();
+
+    let mut expected_url = Url::parse(url).unwrap();
+    // PgConnectOptions defaults
+    let query_string = "ssl-mode=PREFERRED&statement-cache-capacity=100";
+    expected_url.set_query(Some(query_string));
+
+    assert_eq!(expected_url, opts.build_url());
+}

sqlx-sqlite/src/options/connect.rs

@@ -24,6 +24,10 @@ impl ConnectOptions for SqliteConnectOptions {
         Self::from_str(url.as_str())
     }
 
+    fn to_url_lossy(&self) -> Url {
+        self.build_url()
+    }
+
     fn connect(&self) -> BoxFuture<'_, Result<Self::Connection, Error>>
     where
         Self::Connection: Sized,

sqlx-sqlite/src/options/mod.rs

@@ -211,6 +211,11 @@ impl SqliteConnectOptions {
         self
     }
 
+    /// Gets the current name of the database file.
+    pub fn get_filename(self) -> Cow<'static, Path> {
+        self.filename
+    }
+
     /// Set the enforcement of [foreign key constraints](https://www.sqlite.org/pragma.html#pragma_foreign_keys).
     ///
     /// SQLx chooses to enable this by default so that foreign keys function as expected,

sqlx-sqlite/src/options/parse.rs

@@ -1,10 +1,11 @@
 use crate::error::Error;
 use crate::SqliteConnectOptions;
-use percent_encoding::percent_decode_str;
+use percent_encoding::{percent_decode_str, utf8_percent_encode, NON_ALPHANUMERIC};
 use std::borrow::Cow;
 use std::path::{Path, PathBuf};
 use std::str::FromStr;
 use std::sync::atomic::{AtomicUsize, Ordering};
+use url::Url;
 
 // https://www.sqlite.org/uri.html
 
@@ -111,6 +112,36 @@ impl SqliteConnectOptions {
 
         Ok(options)
     }
+
+    pub(crate) fn build_url(&self) -> Url {
+        let filename =
+            utf8_percent_encode(&self.filename.to_string_lossy(), NON_ALPHANUMERIC).to_string();
+        let mut url =
+            Url::parse(&format!("sqlite://{}", filename)).expect("BUG: generated un-parseable URL");
+
+        let mode = match (self.in_memory, self.create_if_missing, self.read_only) {
+            (true, _, _) => "memory",
+            (false, true, _) => "rwc",
+            (false, false, true) => "ro",
+            (false, false, false) => "rw",
+        };
+        url.query_pairs_mut().append_pair("mode", mode);
+
+        let cache = match self.shared_cache {
+            true => "shared",
+            false => "private",
+        };
+        url.query_pairs_mut().append_pair("cache", cache);
+
+        url.query_pairs_mut()
+            .append_pair("immutable", &self.immutable.to_string());
+
+        if let Some(vfs) = &self.vfs {
+            url.query_pairs_mut().append_pair("vfs", &vfs);
+        }
+
+        url
+    }
 }
 
 impl FromStr for SqliteConnectOptions {
@@ -169,3 +200,14 @@ fn test_parse_shared_in_memory() -> Result<(), Error> {
 
     Ok(())
 }
+
+#[test]
+fn it_returns_the_parsed_url() -> Result<(), Error> {
+    let url = "sqlite://test.db?mode=rw&cache=shared";
+    let options: SqliteConnectOptions = url.parse()?;
+
+    let expected_url = Url::parse(url).unwrap();
+    assert_eq!(options.build_url(), expected_url);
+
+    Ok(())
+}