try to support nested cli command definitions

diff --git a/src/bin/pbs-datastore.rs b/src/bin/pbs-datastore.rs
index 3f81b61ed1e7a668e9f06c342ce1f9620a8cc728..ce8b3ba84844fe7a91e28f6d300cfa7486bfdefb 100644 (file)
--- a/src/bin/pbs-datastore.rs
+++ b/src/bin/pbs-datastore.rs
@@ -17,37 +17,67 @@ fn print_cli_usage() {
     eprintln!("Usage: TODO");
 }
 
-type CliCommandDefinition = HashMap<String, CliCommand>;
 
-fn run_cli_command(def: &CliCommandDefinition) -> Result<(), Error> {
+fn handle_simple_command(cli_cmd: &CliCommand, args: Vec<String>) -> Result<(), Error> {
 
-    let mut args: Vec<String> = std::env::args().skip(1).collect();
+    let (params, rest) = getopts::parse_arguments(
+        &args, &cli_cmd.arg_param, &cli_cmd.info.parameters)?;
+
+    if !rest.is_empty() {
+        bail!("got additional arguments: {:?}", rest);
+    }
+
+    let res = (cli_cmd.info.handler)(params,  &cli_cmd.info)?;
+
+    println!("Result: {}", serde_json::to_string_pretty(&res).unwrap());
+
+    Ok(())
+}
+
+fn handle_nested_command(def: &HashMap<String, CmdDef>, mut args: Vec<String>) -> Result<(), Error> {
 
     if args.len() < 1 {
-        bail!("no command specified.");
+        let mut cmds: Vec<&String> = def.keys().collect();
+        cmds.sort();
+
+        let list = cmds.iter().fold(String::new(),|mut s,item| {
+            if !s.is_empty() { s+= ", "; }
+            s += item;
+            s
+        });
+
+        bail!("expected command argument, but no command specified.\nPossible commands: {}", list);
     }
 
     let command = args.remove(0);
 
-    let cli_cmd = match def.get(&command) {
+    let sub_cmd = match def.get(&command) {
         Some(cmd) => cmd,
         None => {
             bail!("no such command '{}'", command);
         }
     };
 
-    let (params, rest) = getopts::parse_arguments(
-        &args, &cli_cmd.arg_param, &cli_cmd.info.parameters)?;
-
-    if !rest.is_empty() {
-        bail!("got additional arguments: {:?}", rest);
+    match sub_cmd {
+        CmdDef::Simple(cli_cmd) => {
+            handle_simple_command(cli_cmd, args)?;
+        }
+        CmdDef::Nested(map) => {
+            handle_nested_command(map, args)?;
+        }
     }
 
-    let res = (cli_cmd.info.handler)(params,  &cli_cmd.info)?;
+    Ok(())
+}
 
-    println!("Result: {}", serde_json::to_string_pretty(&res).unwrap());
+fn run_cli_command(def: &CmdDef) -> Result<(), Error> {
 
-    Ok(())
+    let args: Vec<String> = std::env::args().skip(1).collect();
+
+    match def {
+        CmdDef::Simple(cli_cmd) => handle_simple_command(cli_cmd, args),
+        CmdDef::Nested(map) => handle_nested_command(map, args),
+    }
 }
 
 struct CliCommand {
@@ -56,29 +86,43 @@ struct CliCommand {
     fixed_param: Vec<&'static str>,
 }
 
-fn main() {
+enum CmdDef {
+    Simple(CliCommand),
+    Nested(HashMap<String, CmdDef>),
+}
+
+fn datastore_commands() -> CmdDef {
 
     let mut cmd_def = HashMap::new();
 
-    cmd_def.insert("list".to_owned(), CliCommand {
+    cmd_def.insert("list".to_owned(), CmdDef::Simple(CliCommand {
         info: api3::config::datastore::get(),
         arg_param: vec![],
         fixed_param: vec![],
-    });
+    }));
 
-    cmd_def.insert("create".to_owned(), CliCommand {
+    cmd_def.insert("create".to_owned(), CmdDef::Simple(CliCommand {
         info: api3::config::datastore::post(),
         arg_param: vec!["name", "path"],
         fixed_param: vec![],
-    });
+    }));
 
-    cmd_def.insert("remove".to_owned(), CliCommand {
+    cmd_def.insert("remove".to_owned(), CmdDef::Simple(CliCommand {
         info: api3::config::datastore::delete(),
         arg_param: vec!["name"],
         fixed_param: vec![],
-    });
+    }));
+
+    CmdDef::Nested(cmd_def)
+}
+
+fn main() {
+
+    let mut cmd_def = HashMap::new();
+
+    cmd_def.insert("datastore".to_owned(), datastore_commands());
 
-    if let Err(err) = run_cli_command(&cmd_def) {
+    if let Err(err) = run_cli_command(&CmdDef::Nested(cmd_def)) {
         eprintln!("Error: {}", err);
         print_cli_usage();
         std::process::exit(-1);