From 9b6893ca48c193ba92f7652a6d40965c0d3434ca Mon Sep 17 00:00:00 2001
From: Paul <paulmakles@gmail.com>
Date: Tue, 14 Sep 2021 15:07:41 +0100
Subject: [PATCH] Write database migration for last_message_id. #67

---
 set_version.sh                     |  2 +-
 src/database/entities/message.rs   |  1 -
 src/database/migrations/scripts.rs | 58 +++++++++++++++++++++++++++++-
 src/version.rs                     |  2 +-
 4 files changed, 59 insertions(+), 4 deletions(-)

diff --git a/set_version.sh b/set_version.sh
index b576d45c..783f4f68 100755
--- a/set_version.sh
+++ b/set_version.sh
@@ -1,3 +1,3 @@
 #!/bin/bash
-export version=0.5.3-alpha.0-patch.1
+export version=0.5.3-alpha.1
 echo "pub const VERSION: &str = \"${version}\";" > src/version.rs
diff --git a/src/database/entities/message.rs b/src/database/entities/message.rs
index 7305e8c5..c853841e 100644
--- a/src/database/entities/message.rs
+++ b/src/database/entities/message.rs
@@ -9,7 +9,6 @@ use futures::StreamExt;
 use mongodb::options::UpdateOptions;
 use mongodb::{
     bson::{doc, to_bson, DateTime, Document},
-    options::FindOptions,
 };
 use rauth::entities::{Model, Session};
 use rocket::serde::json::Value;
diff --git a/src/database/migrations/scripts.rs b/src/database/migrations/scripts.rs
index d8ef0b81..c4e6bfbb 100644
--- a/src/database/migrations/scripts.rs
+++ b/src/database/migrations/scripts.rs
@@ -11,7 +11,7 @@ struct MigrationInfo {
     revision: i32,
 }
 
-pub const LATEST_REVISION: i32 = 9;
+pub const LATEST_REVISION: i32 = 10;
 
 pub async fn migrate_database() {
     let migrations = get_collection("migrations");
@@ -286,6 +286,62 @@ pub async fn run_migrations(revision: i32) -> i32 {
             .unwrap();
     }
 
+    if revision <= 9 {
+        info!("Running migration [revision 9 / 2021-09-14]: Switch from last_message to last_message_id.");
+
+        let mut cursor = get_collection("channels")
+            .find(doc! { }, None)
+            .await
+            .unwrap();
+        
+        while let Some(doc) = cursor.next().await {
+            if let Ok(channel) = doc {
+                let channel_id = channel.get_str("_id").unwrap();
+                if let Some(last_message) = channel.get("last_message") {
+                    #[derive(Serialize, Deserialize, Debug, Clone)]
+                    pub struct Obj {
+                        #[serde(rename = "_id")]
+                        id: String,
+                    }
+
+                    #[derive(Serialize, Deserialize, Debug, Clone)]
+                    #[serde(untagged)]
+                    pub enum LastMessage {
+                        Obj(Obj),
+                        Id(String)
+                    }
+
+                    let lm = from_bson::<LastMessage>(last_message.clone()).unwrap();
+                    let id = match lm {
+                        LastMessage::Obj(Obj { id }) => id,
+                        LastMessage::Id(id) => id
+                    };
+
+                    info!("Converting session {} to new format.", &channel_id);
+                    get_collection("channels")
+                        .update_one(
+                            doc! {
+                                "_id": channel_id
+                            },
+                            doc! {
+                                "$set": {
+                                    "last_message_id": id
+                                },
+                                "$unset": {
+                                    "last_message": 1,
+                                }
+                            },
+                            None
+                        )
+                        .await
+                        .unwrap();
+                } else {
+                    info!("{} has no last_message.", &channel_id);
+                }
+            }
+        }
+    }
+
     // Need to migrate fields on attachments, change `user_id`, `object_id`, etc to `parent`.
 
     // Reminder to update LATEST_REVISION when adding new migrations.
diff --git a/src/version.rs b/src/version.rs
index 6e66639f..528324c5 100644
--- a/src/version.rs
+++ b/src/version.rs
@@ -1 +1 @@
-pub const VERSION: &str = "0.5.3-alpha.0-patch.1";
+pub const VERSION: &str = "0.5.3-alpha.1";