add 'db migrate' subcommand

src/cli.rs

@@ -9,6 +9,7 @@ use clap::{Parser, Subcommand};
 
 use crate::error;
 
+mod migrate_db;
 mod serve;
 
 /// Command line arguments
@@ -26,6 +27,10 @@ pub(crate) struct Args {
 pub(crate) enum Command {
     /// Run the server.
     Serve(ServeArgs),
+
+    /// Commands for interacting with the database.
+    #[clap(subcommand)]
+    Db(DbCommand),
 }
 
 /// Wrapper for the `--config` arg.
@@ -57,10 +62,38 @@ pub(crate) struct ServeArgs {
     pub(crate) config: ConfigArg,
 }
 
+#[derive(Subcommand)]
+pub(crate) enum DbCommand {
+    /// Migrate database from one server implementation to another.
+    ///
+    /// This command is not protected against symlink-swapping attacks. Do not
+    /// use it when any subdirectories or parents of the `--in`, `--out`, or
+    /// `--inplace` directories may be written by an untrusted user during
+    /// execution.
+    Migrate(MigrateDbArgs),
+}
+
+#[derive(clap::Args)]
+pub(crate) struct MigrateDbArgs {
+    #[clap(flatten)]
+    config: ConfigArg,
+
+    /// Path to read database from.
+    #[clap(long = "in", short)]
+    pub(crate) in_path: PathBuf,
+
+    /// Path to write migrated database to.
+    #[clap(long = "out", short)]
+    pub(crate) out_path: PathBuf,
+}
+
 impl Args {
     pub(crate) async fn run(self) -> Result<(), error::Main> {
         match self.command {
             Command::Serve(args) => serve::run(args).await?,
+            Command::Db(DbCommand::Migrate(args)) => {
+                migrate_db::run(args).await?;
+            }
         }
         Ok(())
     }