show attributes of current database

tools/cli/src/mentat_cli/command_parser.rs

@@ -38,6 +38,7 @@ pub static CLOSE_COMMAND: &'static str = &"close";
 pub static LONG_QUERY_COMMAND: &'static str = &"query";
 pub static SHORT_QUERY_COMMAND: &'static str = &"q";
 pub static SCHEMA_COMMAND: &'static str = &"schema";
+pub static ATTRIBUTES_COMMAND: &'static str = &"attributes";
 pub static LONG_TRANSACT_COMMAND: &'static str = &"transact";
 pub static SHORT_TRANSACT_COMMAND: &'static str = &"t";
 pub static LONG_EXIT_COMMAND: &'static str = &"exit";
@@ -51,6 +52,7 @@ pub enum Command {
     Open(String),
     Query(String),
     Schema,
+    Attributes,
     Transact(String),
 }
 
@@ -69,7 +71,8 @@ impl Command {
             &Command::Open(_) |
             &Command::Close |
             &Command::Exit |
-            &Command::Schema => true
+            &Command::Schema |
+            &Command::Attributes => true
         }
     }
 
@@ -96,6 +99,9 @@ impl Command {
             &Command::Schema => {
                 format!(".{}", SCHEMA_COMMAND)
             },
+            &Command::Attributes => {
+                format!(".{}", ATTRIBUTES_COMMAND)
+            },
         }
     }
 }
@@ -144,6 +150,15 @@ pub fn command(s: &str) -> Result<Command, cli::Error> {
                         }
                         Ok(Command::Schema)
                     });
+                    
+    let attributes_parser = string(ATTRIBUTES_COMMAND)
+                    .with(no_arg_parser())
+                    .map(|args| {
+                        if !args.is_empty() {
+                            bail!(cli::ErrorKind::CommandParse(format!("Unrecognized argument {:?}", args[0])) );
+                        }
+                        Ok(Command::Attributes)
+                    });
 
     let exit_parser = try(string(LONG_EXIT_COMMAND)).or(try(string(SHORT_EXIT_COMMAND)))
                     .with(no_arg_parser())
@@ -176,13 +191,14 @@ pub fn command(s: &str) -> Result<Command, cli::Error> {
 
     spaces()
     .skip(token('.'))
-    .with(choice::<[&mut Parser<Input = _, Output = Result<Command, cli::Error>>; 7], _>
+    .with(choice::<[&mut Parser<Input = _, Output = Result<Command, cli::Error>>; 8], _>
           ([&mut try(help_parser),
             &mut try(open_parser),
             &mut try(close_parser),
             &mut try(exit_parser),
             &mut try(query_parser),
             &mut try(schema_parser),
+            &mut try(attributes_parser),
             &mut try(transact_parser)]))
         .parse(s)
         .unwrap_or((Err(cli::ErrorKind::CommandParse(format!("Invalid command {:?}", s)).into()), "")).0
@@ -390,6 +406,33 @@ mod tests {
         }
     }
 
+    #[test]
+    fn test_attributes_parser_with_args() {
+        let input = ".attributes arg1";
+        let err = command(&input).expect_err("Expected an error");
+        assert_eq!(err.to_string(), format!("Invalid command {:?}", input));
+    }
+
+    #[test]
+    fn test_attributes_parser_no_args() {
+        let input = ".attributes";
+        let cmd = command(&input).expect("Expected attributes command");
+        match cmd {
+            Command::Attributes => assert!(true),
+            _ => assert!(false)
+        }
+    }
+    
+    #[test]
+    fn test_attributes_parser_no_args_trailing_whitespace() {
+        let input = ".attributes ";
+        let cmd = command(&input).expect("Expected attributes command");
+        match cmd {
+            Command::Attributes => assert!(true),
+            _ => assert!(false)
+        }
+    }
+
     #[test]
     fn test_query_parser_complete_edn() {
         let input = ".q [:find ?x :where [?x foo/bar ?y]]";

tools/cli/src/mentat_cli/repl.rs

@@ -27,6 +27,7 @@ use command_parser::{
     SHORT_TRANSACT_COMMAND,
     LONG_EXIT_COMMAND,
     SHORT_EXIT_COMMAND,
+    ATTRIBUTES_COMMAND,
 };
 use input::InputReader;
 use input::InputResult::{
@@ -43,6 +44,7 @@ use store::{
 lazy_static! {
     static ref COMMAND_HELP: HashMap<&'static str, &'static str> = {
         let mut map = HashMap::new();
+        map.insert(ATTRIBUTES_COMMAND, "Output the attributes for the schema in the current open database.");
         map.insert(LONG_EXIT_COMMAND, "Close the current database and exit the REPL.");
         map.insert(SHORT_EXIT_COMMAND, "Shortcut for `.exit`. Close the current database and exit the REPL.");
         map.insert(HELP_COMMAND, "Show help for commands.");
@@ -120,8 +122,14 @@ impl Repl {
                     Ok(s) => println!("{}", s),
                     Err(e) => println!("{}", e)
                 };
-                
+            },
-            }
+            Command::Attributes => {
+                let edn = self.store.fetch_attributes();
+                match edn.to_pretty(120) {
+                    Ok(s) => println!("{}", s),
+                    Err(e) => println!("{}", e)
+                };
+            },
             Command::Transact(transaction) => self.execute_transact(transaction),
             Command::Exit => {
                 self.close();

tools/cli/src/mentat_cli/store.rs

@@ -62,7 +62,24 @@ impl Store {
         Ok(self.conn.transact(&mut self.handle, &transaction)?)
     }
 
+    // the schema is the entire schema of the store including structure used to describe the store.
     pub fn fetch_schema(&self) -> edn::Value {
         self.conn.current_schema().to_edn_value()
     }
+
+    // the attributes are the specific attributes added to the schema for this particular store.
+    pub fn fetch_attributes(&self) -> edn::Value {
+        let schema = self.conn.current_schema();
+
+        edn::Value::Vector((&schema.schema_map).iter()
+            .filter_map(|(entid, attribute)| {
+                if let Some(ident) = schema.get_ident(*entid) {
+                    if !ident.namespace.starts_with("db") {
+                        return Some(attribute.to_edn_value(Some(ident.clone())));
+                    }
+                }
+                return None;
+            })
+            .collect())
+    }
 }