refactor: cleanup client output

client/src/main.rs

@@ -1,3 +1,4 @@
+use std::io::Write;
 use clap::Parser;
 use proto::handshake::client::do_client_handshake;
 use proto::handshake::request::HandshakeRequest;
@@ -5,7 +6,7 @@ use proto::reader::protoreader::ProtoReader;
 use proto::writer::protowriter::{ProtoFlush, ProtoWriter};
 use tokio::io::{BufReader, BufWriter};
 use tokio::net::TcpStream;
-use proto::message::backend::{BackendMessage, DataRowData, RowDescriptionData};
+use proto::message::backend::{BackendMessage, CommandCompleteData, DataRowData, ErrorResponseData, RowDescriptionData};
 use proto::message::frontend::{FrontendMessage, QueryData};
 use proto::reader::oneway::OneWayProtoReader;
 use proto::writer::oneway::OneWayProtoWriter;
@@ -19,12 +20,17 @@ struct Cli {
     /// Host name or IP address of the server.
     #[arg(long, default_value = "127.0.0.1", help = "Host name or IP address of the server")]
     host: String,
+
+    /// User name sent to the server.
+    #[arg(long, default_value = "minisql user", help = "User name")]
+    username: String,
 }
 
 #[tokio::main]
 async fn main() -> anyhow::Result<()> {
     let cli = Cli::parse();
     let addr = format!("{}:{}", cli.host, cli.port);
+    println!("Connecting to {}", addr);
 
     let mut stream = TcpStream::connect(addr).await?;
     let (reader, writer) = stream.split();
@@ -33,42 +39,55 @@ async fn main() -> anyhow::Result<()> {
     let mut reader = ProtoReader::new(BufReader::new(reader), 1024);
 
     let request = HandshakeRequest::new(196608)
-        .parameter("user", "test user")
+        .parameter("user", cli.username.as_str())
         .parameter("client_encoding", "UTF8");
 
-    let response = do_client_handshake(&mut writer, &mut reader, request).await?;
-
-    println!("Handshake complete:\n{response:?}");
+    let _ = do_client_handshake(&mut writer, &mut reader, request).await?;
+    println!("Connected to the server");
 
+    let mut exit = false;
+    let command = prompt()?;
+    if let Some(cmd) = command {
         writer.write_proto(FrontendMessage::Query(QueryData {
-        query: "SELECT * FROM users;".to_string().into(),
+            query: cmd.into(),
         })).await?;
         writer.flush().await?;
-    let mut line = String::new();
-    loop {
+    } else {
+        exit = true;
+    }
+
+    while !exit {
         let msg: BackendMessage = reader.read_proto().await?;
         match msg {
             BackendMessage::RowDescription(data) => {
-                print_header(data);
+                print_row_description(data);
             },
             BackendMessage::DataRow(data) => {
-                print_row(data);
+                print_row_data(data);
             },
             BackendMessage::CommandComplete(data) => {
-                println!("Command complete: {:?}", data);
+                print_command_complete(data);
+            },
+            BackendMessage::ErrorResponse(data) => {
+                print_error_response(data);
+            },
+            BackendMessage::EmptyQueryResponse => {
+                println!("Empty query response");
+            },
+            BackendMessage::NoData => {
+                println!("No data");
             },
             BackendMessage::ReadyForQuery(data) => {
-                println!("Ready for query: {:?}", data);
-                line.clear();
-                let res = std::io::stdin().read_line(&mut line);
-                if let Ok(_) = res {
-                    if line.eq("exit") {
-                        break;
-                    }
+                println!("Ready for next query ({})", data.status);
+
+                let command = prompt()?;
+                if let Some(cmd) = command {
                     writer.write_proto(FrontendMessage::Query(QueryData {
-                        query: line.clone().into(),
+                        query: cmd.into(),
                     })).await?;
                     writer.flush().await?;
+                } else {
+                    exit = true;
                 }
             },
             m => {
@@ -83,21 +102,70 @@ async fn main() -> anyhow::Result<()> {
     Ok(())
 }
 
-fn print_header(header: RowDescriptionData) {
-    print!("Header -> ");
-    for column in Vec::from(header.columns) {
-        print!("{} | ", column.name.as_str());
+fn prompt() -> std::io::Result<Option<String>> {
+    print!("> ");
+    std::io::stdout().flush()?;
+
+    let mut line = String::new();
+    let _ = std::io::stdin().read_line(&mut line)?;
+
+    let line = line.trim();
+
+    if line.is_empty() {
+        return prompt();
+    }
+
+    if line == "exit" || line == "quit" {
+        return Ok(None);
+    }
+
+    Ok(Some(line.trim().to_string()))
+}
+
+fn print_error_response(data: ErrorResponseData) {
+    println!("Error with code {}: {}", data.code, data.message.as_str());
+}
+
+fn print_command_complete(data: CommandCompleteData) {
+    println!("Result: {}", data.tag.as_str());
+}
+
+fn print_row_description(data: RowDescriptionData) {
+    let mut lengths = vec![];
+
+    let columns = Vec::from(data.columns);
+    for i in 0..columns.len() {
+        let column_name = columns[i].name.as_str();
+        lengths.push(column_name.len());
+        print!("{}", column_name);
+        if i < columns.len() - 1 {
+            print!(" | ");
+        }
+    }
+
+    println!();
+    for i in 0..lengths.len() {
+        for _ in 0..lengths[i] {
+            print!("-");
+        }
+        if i < lengths.len() - 1 {
+            print!("-+-");
+        }
     }
     println!();
 }
 
-fn print_row(row: DataRowData) {
-    print!("Row    -> ");
-    for column in Vec::from(row.columns) {
-        let bytes = Vec::from(column);
+fn print_row_data(data: DataRowData) {
+    let columns = Vec::from(data.columns);
+    let length = columns.len();
+    for column in columns.into_iter().enumerate() {
+        let bytes = Vec::from(column.1);
         let string = String::from_utf8(bytes).unwrap();
 
-        print!("{} | ", string);
+        print!("{}", string);
+        if column.0 < length - 1 {
+            print!(" | ");
+        }
     }
     println!();
 }