Add instance stats to object returned by /api/v1/instance

docs/openapi.yaml

@@ -1038,6 +1038,19 @@ components:
         registrations:
           description: Whether registrations are enabled.
           type: boolean
+        stats:
+          description: Statistics about how much information the instance contains.
+          type: object
+          properties:
+            user_count:
+              description: Users registered on this instance
+              type: integer
+            status_count:
+              description: Statuses authored by users on instance.
+              type: integer
+            domain_count:
+              description: Domains federated with this instance.
+              type: integer
         login_message:
           description: Login message for signer.
           type: string

src/mastodon_api/instance/types.rs

@@ -5,6 +5,13 @@ use crate::config::{BlockchainConfig, Config};
 use crate::ethereum::contracts::ContractSet;
 use crate::mastodon_api::MASTODON_API_VERSION;
 
+#[derive(Serialize)]
+struct InstanceStats {
+    user_count: i64,
+    status_count: i64,
+    domain_count: i64,
+}
+
 #[derive(Serialize)]
 struct BlockchainFeatures {
     minter: bool,
@@ -27,6 +34,7 @@ pub struct InstanceInfo {
     description: String,
     version: String,
     registrations: bool,
+    stats: InstanceStats,
 
     login_message: String,
     post_character_limit: usize,
@@ -43,7 +51,13 @@ fn get_full_api_version(version: &str) -> String {
 }
 
 impl InstanceInfo {
-    pub fn create(config: &Config, maybe_blockchain: Option<&ContractSet>) -> Self {
+    pub fn create(
+        config: &Config,
+        maybe_blockchain: Option<&ContractSet>,
+        user_count: i64,
+        post_count: i64,
+        peer_count: i64,
+    ) -> Self {
         let mut blockchains = vec![];
         match config.blockchain() {
             Some(BlockchainConfig::Ethereum(ethereum_config)) => {
@@ -90,6 +104,11 @@ impl InstanceInfo {
             description: config.instance_description.clone(),
             version: get_full_api_version(&config.version),
             registrations: config.registrations_open,
+            stats: InstanceStats {
+                user_count,
+                status_count: post_count,
+                domain_count: peer_count,
+            },
             login_message: config.login_message.clone(),
             post_character_limit: config.post_character_limit,
             blockchains: blockchains,

src/mastodon_api/instance/views.rs

@@ -1,18 +1,32 @@
 use actix_web::{get, web, HttpResponse, Scope};
 
 use crate::config::Config;
+use crate::database::{Pool, get_database_client};
 use crate::errors::HttpError;
 use crate::ethereum::contracts::ContractSet;
+use crate::models::{
+    instances::queries::get_peer_count,
+    posts::queries::get_local_post_count,
+    users::queries::get_user_count,
+};
 use super::types::InstanceInfo;
 
 #[get("")]
 async fn instance_view(
     config: web::Data<Config>,
+    db_pool: web::Data<Pool>,
     maybe_blockchain: web::Data<Option<ContractSet>>,
 ) -> Result<HttpResponse, HttpError> {
+    let db_client = &**get_database_client(&db_pool).await?;
+    let user_count = get_user_count(db_client).await?;
+    let post_count = get_local_post_count(db_client).await?;
+    let peer_count = get_peer_count(db_client).await?;
     let instance = InstanceInfo::create(
         config.as_ref(),
         maybe_blockchain.as_ref().as_ref(),
+        user_count,
+        post_count,
+        peer_count,
     );
     Ok(HttpResponse::Ok().json(instance))
 }

src/models/instances/mod.rs

@@ -0,0 +1 @@
+pub mod queries;

src/models/instances/queries.rs

@@ -0,0 +1,28 @@
+use tokio_postgres::GenericClient;
+
+use crate::errors::DatabaseError;
+
+pub async fn create_instance(
+    db_client: &impl GenericClient,
+    hostname: &str,
+) -> Result<(), DatabaseError> {
+    db_client.execute(
+        "
+        INSERT INTO instance VALUES ($1)
+        ON CONFLICT DO NOTHING
+        ",
+        &[&hostname],
+    ).await?;
+    Ok(())
+}
+
+pub async fn get_peer_count(
+    db_client: &impl GenericClient,
+) -> Result<i64, DatabaseError> {
+    let row = db_client.query_one(
+        "SELECT count(instance) FROM instance",
+        &[],
+    ).await?;
+    let count = row.try_get("count")?;
+    Ok(count)
+}

src/models/mod.rs

@@ -1,5 +1,6 @@
 pub mod attachments;
 pub mod cleanup;
+pub mod instances;
 pub mod invoices;
 pub mod markers;
 pub mod notifications;

src/models/profiles/queries.rs

@@ -10,6 +10,7 @@ use crate::models::cleanup::{
     find_orphaned_ipfs_objects,
     DeletionQueue,
 };
+use crate::models::instances::queries::create_instance;
 use crate::models::relationships::types::RelationshipType;
 use crate::utils::currencies::Currency;
 use crate::utils::id::new_uuid;
@@ -29,13 +30,7 @@ pub async fn create_profile(
 ) -> Result<DbActorProfile, DatabaseError> {
     let profile_id = new_uuid();
     if let Some(ref hostname) = profile_data.hostname {
-        db_client.execute(
-            "
-            INSERT INTO instance VALUES ($1)
-            ON CONFLICT DO NOTHING
-            ",
-            &[&hostname],
-        ).await?;
+        create_instance(db_client, hostname).await?;
     };
     let row = db_client.query_one(
         "