Merge pull request #171 from kyeah/db-version

Add `db.version()` function

Author: saghm

Cargo.toml

@@ -20,6 +20,7 @@ rand = "0.3.14"
 rust-crypto = "0.2.31"
 rustc-serialize = "0.3.19"
 scan_fmt = "0.1.0"
+semver = "0.5.0"
 separator = "0.3.1"
 textnonce = { version = "0.4.1", default-features = false }
 time = "0.1.35"

src/command_type.rs

@@ -4,6 +4,7 @@
 #[derive(PartialEq, Eq, Clone)]
 pub enum CommandType {
     Aggregate,
+    BuildInfo,
     Count,
     CreateCollection,
     CreateIndexes,
@@ -37,6 +38,7 @@ impl CommandType {
     pub fn to_str(&self) -> &str {
         match *self {
             CommandType::Aggregate => "aggregate",
+            CommandType::BuildInfo => "buildinfo",
             CommandType::Count => "count",
             CommandType::CreateCollection => "create_collection",
             CommandType::CreateIndexes => "create_indexes",
@@ -87,6 +89,7 @@ impl CommandType {
             CommandType::UpdateMany |
             CommandType::UpdateOne => true,
             CommandType::Aggregate |
+            CommandType::BuildInfo |
             CommandType::Count |
             CommandType::Distinct |
             CommandType::Find |

src/db/mod.rs

@@ -62,13 +62,15 @@ use auth::Authenticator;
 use bson;
 use bson::Bson;
 use {Client, CommandType, ThreadedClient, Result};
-use Error::{CursorNotFoundError, OperationError};
+use Error::{CursorNotFoundError, OperationError, ResponseError};
 use coll::Collection;
 use coll::options::FindOptions;
 use common::{ReadPreference, WriteConcern};
 use cursor::{Cursor, DEFAULT_BATCH_SIZE};
 use self::options::{CreateCollectionOptions, CreateUserOptions, UserInfoOptions};
 use self::roles::Role;
+use semver::Version;
+use std::error::Error;
 use std::sync::Arc;
 
 /// Interfaces with a MongoDB database.
@@ -93,6 +95,8 @@ pub trait ThreadedDatabase {
             read_preference: Option<ReadPreference>,
             write_concern: Option<WriteConcern>)
             -> Database;
+    // Returns the version of the MongoDB instance.
+    fn version(&self) -> Result<Version>;
     /// Logs in a user using the SCRAM-SHA-1 mechanism.
     fn auth(&self, user: &str, password: &str) -> Result<()>;
     /// Creates a collection representation with inherited read and write controls.
@@ -275,6 +279,21 @@ impl ThreadedDatabase for Database {
         }
     }
 
+    fn version(&self) -> Result<Version> {
+        let doc = doc! { "buildinfo" => 1 };
+        let out = try!(self.command(doc,
+                                    CommandType::BuildInfo,
+                                    None));
+
+        match out.get("version") {
+            Some(&Bson::String(ref s)) => match Version::parse(s) {
+                Ok(v) => Ok(v),
+                Err(e) => Err(ResponseError(String::from(e.description()))),
+            },
+            _ => Err(ResponseError(String::from("No version received from server"))),
+        }
+    }
+
     fn create_collection(&self,
                          name: &str,
                          options: Option<CreateCollectionOptions>)

src/lib.rs

@@ -97,6 +97,7 @@ extern crate rand;
 extern crate rustc_serialize;
 #[macro_use]
 extern crate scan_fmt;
+extern crate semver;
 extern crate separator;
 extern crate textnonce;
 extern crate time;

tests/client/db.rs

@@ -167,3 +167,10 @@ fn create_and_get_users() {
         _ => panic!("User isn't named 'val' but should be"),
     };
 }
+
+#[test]
+fn get_version() {
+    let client = Client::connect("localhost", 27017).unwrap();
+    let db = client.db("get_version");
+    let version = db.version().unwrap();
+}