Add ability to start from different views via subcommands

The following views are supported:
- queries             Show now running queries (from system.processes)
- last-queries        Show last running queries (from system.query_log)
- slow-queries        Show slow (slower then 1 second, ordered by duration) queries (from system.query_log)
- merges              Show merges for MergeTree engine (system.merges)
- mutations           Show mutations for MergeTree engine (system.mutations)
- replication-queue   Show replication queue for ReplicatedMergeTree engine (system.replication_queue)
- replicated-fetches  Show fetches for ReplicatedMergeTree engine (system.replicated_fetches)
- replicas            Show information about replicas (system.replicas)
- errors              Show all errors that happend in a server since start (system.errors)
- backups             Show information about backups (system.backups)

src/interpreter/options.rs

@@ -1,4 +1,4 @@
-use clap::{builder::ArgPredicate, ArgAction, Args, CommandFactory, Parser};
+use clap::{builder::ArgPredicate, ArgAction, Args, CommandFactory, Parser, Subcommand};
 use clap_complete::{generate, Shell};
 use quick_xml::de::Deserializer;
 use serde::Deserialize;
@@ -31,6 +31,30 @@ struct ClickHouseClientConfig {
     connections_credentials: Option<ClickHouseClientConfigConnectionsCredentialsConnection>,
 }
 
+#[derive(Debug, Clone, Subcommand)]
+pub enum ChDigViews {
+    /// Show now running queries (from system.processes)
+    Queries,
+    /// Show last running queries (from system.query_log)
+    LastQueries,
+    /// Show slow (slower then 1 second, ordered by duration) queries (from system.query_log)
+    SlowQueries,
+    /// Show merges for MergeTree engine (system.merges)
+    Merges,
+    /// Show mutations for MergeTree engine (system.mutations)
+    Mutations,
+    /// Show replication queue for ReplicatedMergeTree engine (system.replication_queue)
+    ReplicationQueue,
+    /// Show fetches for ReplicatedMergeTree engine (system.replicated_fetches)
+    ReplicatedFetches,
+    /// Show information about replicas (system.replicas)
+    Replicas,
+    /// Show all errors that happend in a server since start (system.errors)
+    Errors,
+    /// Show information about backups (system.backups)
+    Backups,
+}
+
 #[derive(Parser, Clone)]
 #[command(name = "chdig")]
 #[command(author, version, about, long_about = None)]
@@ -39,6 +63,8 @@ pub struct ChDigOptions {
     pub clickhouse: ClickHouseOptions,
     #[command(flatten)]
     pub view: ViewOptions,
+    #[command(subcommand)]
+    pub start_view: Option<ChDigViews>,
     #[command(flatten)]
     internal: InternalOptions,
 }

src/view/navigation.rs

@@ -1,5 +1,5 @@
 use crate::{
-    interpreter::{clickhouse::TraceType, ContextArc, WorkerEvent},
+    interpreter::{clickhouse::TraceType, options::ChDigViews, ContextArc, WorkerEvent},
     view,
 };
 use anyhow::Result;
@@ -135,7 +135,27 @@ impl Navigation for Cursive {
                 ),
         );
 
-        self.show_clickhouse_processes(context.clone());
+        let start_view = context
+            .lock()
+            .unwrap()
+            .options
+            .start_view
+            .clone()
+            .unwrap_or(ChDigViews::Queries);
+        match start_view {
+            ChDigViews::Queries => self.show_clickhouse_processes(context.clone()),
+            ChDigViews::LastQueries => self.show_clickhouse_last_query_log(context.clone()),
+            ChDigViews::SlowQueries => self.show_clickhouse_slow_query_log(context.clone()),
+            ChDigViews::Merges => self.show_clickhouse_merges(context.clone()),
+            ChDigViews::Mutations => self.show_clickhouse_mutations(context.clone()),
+            ChDigViews::ReplicationQueue => self.show_clickhouse_replication_queue(context.clone()),
+            ChDigViews::ReplicatedFetches => {
+                self.show_clickhouse_replicated_fetches(context.clone())
+            }
+            ChDigViews::Replicas => self.show_clickhouse_replicas(context.clone()),
+            ChDigViews::Errors => self.show_clickhouse_errors(context.clone()),
+            ChDigViews::Backups => self.show_clickhouse_backups(context.clone()),
+        }
     }
 
     fn initialize_global_shortcuts(&mut self, context: ContextArc) {