Add postgres code

- Set is currently working
- Other methods to test

Signed-off-by: Lee Smet <lee.smet@hotmail.com>

heromodels/Cargo.toml

@@ -15,11 +15,20 @@ tst = { path = "../tst" }
 heromodels-derive = { path = "../heromodels-derive" }
 heromodels_core = { path = "../heromodels_core" }
 rhailib_derive = { package = "derive", path = "../../rhailib/src/derive" }
-rhai = { version = "1.21.0", features = ["std", "sync", "decimal", "internals"] } # Added "decimal" feature, sync for Arc<Mutex<>>
+rhai = { version = "1.21.0", features = [
+  "std",
+  "sync",
+  "decimal",
+  "internals",
+] } # Added "decimal" feature, sync for Arc<Mutex<>>
 rhai_client_macros = { path = "../rhai_client_macros" }
 strum = "0.26"
 strum_macros = "0.26"
 uuid = { version = "1.17.0", features = ["v4"] }
+postgres = { version = "0.19.10", features = ["with-serde_json-1"] }
+jsonb = "0.5.2"
+r2d2 = "0.8.10"
+r2d2_postgres = "0.18.2"
 
 [features]
 default = []
@@ -46,4 +55,4 @@ path = "examples/flow_example.rs"
 [[example]]
 name = "biz_rhai"
 path = "examples/biz_rhai/example.rs"
-required-features = ["rhai"]
+required-features = ["rhai"]

heromodels/examples/postgres_model_example.rs

@@ -0,0 +1,225 @@
+use heromodels::db::postgres::Config;
+use heromodels::db::{Collection, Db};
+use heromodels::models::userexample::user::user_index::{is_active, username};
+use heromodels::models::{Comment, User};
+use heromodels_core::Model;
+
+// Helper function to print user details
+fn print_user_details(user: &User) {
+    println!("\n--- User Details ---");
+    println!("ID: {}", user.get_id());
+    println!("Username: {}", user.username);
+    println!("Email: {}", user.email);
+    println!("Full Name: {}", user.full_name);
+    println!("Active: {}", user.is_active);
+    println!("Created At: {}", user.base_data.created_at);
+    println!("Modified At: {}", user.base_data.modified_at);
+    println!("Comments: {:?}", user.base_data.comments);
+}
+
+// Helper function to print comment details
+fn print_comment_details(comment: &Comment) {
+    println!("\n--- Comment Details ---");
+    println!("ID: {}", comment.get_id());
+    println!("User ID: {}", comment.user_id);
+    println!("Content: {}", comment.content);
+    println!("Created At: {}", comment.base_data.created_at);
+    println!("Modified At: {}", comment.base_data.modified_at);
+}
+
+fn main() {
+    let db = heromodels::db::postgres::Postgres::new(
+        Config::new()
+            .user(Some("postgres".into()))
+            .password(Some("test123".into()))
+            .host(Some("localhost".into()))
+            .port(Some(5432)),
+    )
+    .expect("Can connect to postgress");
+
+    println!("Hero Models - Basic Usage Example");
+    println!("================================");
+
+    // Create users with auto-generated IDs
+
+    // User 1
+    let user1 = User::new()
+        .username("johndoe")
+        .email("john.doe@example.com")
+        .full_name("John Doe")
+        .is_active(false)
+        .build();
+
+    // User 2
+    let user2 = User::new()
+        .username("janesmith")
+        .email("jane.smith@example.com")
+        .full_name("Jane Smith")
+        .is_active(true)
+        .build();
+
+    // User 3
+    let user3 = User::new()
+        .username("willism")
+        .email("willis.masters@example.com")
+        .full_name("Willis Masters")
+        .is_active(true)
+        .build();
+
+    // User 4
+    let user4 = User::new()
+        .username("carrols")
+        .email("carrol.smith@example.com")
+        .full_name("Carrol Smith")
+        .is_active(false)
+        .build();
+
+    // Save all users to database and get their assigned IDs and updated models
+    let (user1_id, db_user1) = db
+        .collection()
+        .expect("can open user collection")
+        .set(&user1)
+        .expect("can set user");
+    let (user2_id, db_user2) = db
+        .collection()
+        .expect("can open user collection")
+        .set(&user2)
+        .expect("can set user");
+    let (user3_id, db_user3) = db
+        .collection()
+        .expect("can open user collection")
+        .set(&user3)
+        .expect("can set user");
+    let (user4_id, db_user4) = db
+        .collection()
+        .expect("can open user collection")
+        .set(&user4)
+        .expect("can set user");
+
+    println!("User 1 assigned ID: {}", user1_id);
+    println!("User 2 assigned ID: {}", user2_id);
+    println!("User 3 assigned ID: {}", user3_id);
+    println!("User 4 assigned ID: {}", user4_id);
+
+    // We already have the updated models from the set method, so we don't need to retrieve them again
+
+    // Print all users retrieved from database
+    println!("\n--- Users Retrieved from Database ---");
+    println!("\n1. First user:");
+    print_user_details(&db_user1);
+
+    println!("\n2. Second user:");
+    print_user_details(&db_user2);
+
+    println!("\n3. Third user:");
+    print_user_details(&db_user3);
+
+    println!("\n4. Fourth user:");
+    print_user_details(&db_user4);
+
+    // Demonstrate different ways to retrieve users from the database
+
+    // 1. Retrieve by username index
+    println!("\n--- Retrieving Users by Different Methods ---");
+    println!("\n1. By Username Index:");
+    let stored_users = db
+        .collection::<User>()
+        .expect("can open user collection")
+        .get::<username, _>("johndoe")
+        .expect("can load stored user");
+
+    assert_eq!(stored_users.len(), 1);
+    print_user_details(&stored_users[0]);
+
+    // 2. Retrieve by active status
+    println!("\n2. By Active Status (Active = true):");
+    let active_users = db
+        .collection::<User>()
+        .expect("can open user collection")
+        .get::<is_active, _>(&true)
+        .expect("can load stored users");
+
+    assert_eq!(active_users.len(), 2);
+    for (_i, active_user) in active_users.iter().enumerate() {
+        print_user_details(active_user);
+    }
+
+    // 3. Delete a user and show the updated results
+    println!("\n3. After Deleting a User:");
+    let user_to_delete_id = active_users[0].get_id();
+    println!("Deleting user with ID: {}", user_to_delete_id);
+    db.collection::<User>()
+        .expect("can open user collection")
+        .delete_by_id(user_to_delete_id)
+        .expect("can delete existing user");
+
+    // Show remaining active users
+    let active_users = db
+        .collection::<User>()
+        .expect("can open user collection")
+        .get::<is_active, _>(&true)
+        .expect("can load stored users");
+
+    println!("   a. Remaining Active Users:");
+    assert_eq!(active_users.len(), 1);
+    for (_i, active_user) in active_users.iter().enumerate() {
+        print_user_details(active_user);
+    }
+
+    // Show inactive users
+    let inactive_users = db
+        .collection::<User>()
+        .expect("can open user collection")
+        .get::<is_active, _>(&false)
+        .expect("can load stored users");
+
+    println!("   b. Inactive Users:");
+    assert_eq!(inactive_users.len(), 2);
+    for (_i, inactive_user) in inactive_users.iter().enumerate() {
+        print_user_details(inactive_user);
+    }
+
+    println!("\n--- User Model Information ---");
+    println!("User DB Prefix: {}", User::db_prefix());
+
+    // Demonstrate comment creation and association with a user
+    println!("\n--- Working with Comments ---");
+
+    // 1. Create and save a comment
+    println!("\n1. Creating a Comment:");
+    let comment = Comment::new()
+        .user_id(db_user1.get_id()) // commenter's user ID
+        .content("This is a comment on the user")
+        .build();
+
+    // Save the comment and get its assigned ID and updated model
+    let (comment_id, db_comment) = db
+        .collection()
+        .expect("can open comment collection")
+        .set(&comment)
+        .expect("can set comment");
+
+    println!("Comment assigned ID: {}", comment_id);
+
+    println!("   a. Comment Retrieved from Database:");
+    print_comment_details(&db_comment);
+
+    // 3. Associate the comment with a user
+    println!("\n2. Associating Comment with User:");
+    let mut updated_user = db_user1.clone();
+    updated_user.base_data.add_comment(db_comment.get_id());
+
+    // Save the updated user and get the new version
+    let (_, user_with_comment) = db
+        .collection::<User>()
+        .expect("can open user collection")
+        .set(&updated_user)
+        .expect("can set updated user");
+
+    println!("   a. User with Associated Comment:");
+    print_user_details(&user_with_comment);
+
+    println!("\n--- Model Information ---");
+    println!("User DB Prefix: {}", User::db_prefix());
+    println!("Comment DB Prefix: {}", Comment::db_prefix());
+}

heromodels/src/db.rs

@@ -4,6 +4,7 @@ use heromodels_core::{Index, Model};
 use serde::{Deserialize, Serialize};
 
 pub mod hero;
+pub mod postgres;
 
 pub trait Db {
     /// Error type returned by database operations.

heromodels/src/db/postgres.rs

@@ -0,0 +1,400 @@
+use std::time::Duration;
+
+use heromodels_core::Model;
+use postgres::{Client, NoTls};
+use r2d2::Pool;
+use r2d2_postgres::PostgresConnectionManager;
+
+#[derive(Clone)]
+pub struct Postgres {
+    pool: Pool<PostgresConnectionManager<NoTls>>,
+}
+
+/// Configuration used to connect to a postgres server. All values are optional, if they are
+/// [Option::None], the postgres defaults are used.
+#[derive(Default)]
+pub struct Config {
+    pub user: Option<String>,
+    pub password: Option<String>,
+    pub dbname: Option<String>,
+    pub host: Option<String>,
+    pub port: Option<u16>,
+}
+
+impl Config {
+    /// Create a new empty config
+    pub fn new() -> Self {
+        Self::default()
+    }
+
+    /// Set the user value in the config
+    pub fn user(mut self, user: Option<String>) -> Self {
+        self.user = user;
+        self
+    }
+
+    /// Set the password value in the config
+    pub fn password(mut self, password: Option<String>) -> Self {
+        self.password = password;
+        self
+    }
+
+    /// Set the dbname value in the config
+    pub fn dbname(mut self, dbname: Option<String>) -> Self {
+        self.dbname = dbname;
+        self
+    }
+
+    /// Set the host value in the config
+    pub fn host(mut self, host: Option<String>) -> Self {
+        self.host = host;
+        self
+    }
+
+    /// Set the port value in the config
+    pub fn port(mut self, port: Option<u16>) -> Self {
+        self.port = port;
+        self
+    }
+}
+
+#[derive(Debug)]
+pub enum Error {
+    /// An error communicating with the postgres server
+    Postgres(postgres::error::Error),
+    /// An error originating from the connection pool
+    ConnectionPool(r2d2::Error),
+    /// An error encoding to or decoding from json
+    Json(serde_json::Error),
+    /// An error encoding to or decoding from jsonb
+    JsonB(jsonb::Error),
+    /// We tried to insert a value but the row was not returned
+    FailedInsert,
+    /// We tried to update a value but we didn't get the expected 1 modified row
+    FailedUpdate(usize),
+    /// We tried to query the existence of a table but it failed
+    TableExistenceQuery,
+}
+
+impl Postgres {
+    /// Create a new connection to a postgres instance.
+    pub fn new(config: Config) -> Result<Self, Error> {
+        let mut cfg = Client::configure();
+        cfg.user(config.user.unwrap_or_default().as_ref())
+            .password(config.password.unwrap_or_default())
+            .dbname(config.dbname.unwrap_or_default().as_ref())
+            .host(config.host.unwrap_or_default().as_ref())
+            .port(config.port.unwrap_or_default());
+
+        // No TLS support for now
+        // let client = cfg.connect(postgres::tls::NoTls)?;
+        let manager = PostgresConnectionManager::new(cfg, NoTls);
+
+        let pool = Pool::builder()
+            .connection_timeout(Duration::from_secs(1))
+            .max_size(5)
+            .build(manager)?;
+
+        Ok(Postgres { pool })
+    }
+
+    /// Helper method which generates a table name for a model, to alleviate some keyword
+    /// conflicts.
+    fn collection_name<M: Model>() -> String {
+        format!("model_{}", M::db_prefix())
+    }
+}
+
+impl super::Db for Postgres {
+    type Error = Error;
+
+    fn collection<M: heromodels_core::Model>(
+        &self,
+    ) -> Result<impl super::Collection<&str, M>, super::Error<Self::Error>> {
+        // Check if the table exists, if not create it with proper indexes
+        let mut con = self.pool.get().map_err(Error::from)?;
+
+        let row = con
+            .query_one(
+                r#"SELECT EXISTS (
+SELECT 1
+FROM information_schema.tables
+WHERE table_name = $1 
+) AS table_existence;"#,
+                &[&Self::collection_name::<M>()],
+            )
+            .map_err(Error::from)?;
+
+        let exists: bool = row.get("table_existence");
+
+        // If table does not exist set it up
+        if !exists {
+            eprintln!(
+                "Table {} does not exist, create it now",
+                Self::collection_name::<M>()
+            );
+            // Use a transaction here so if index creation failed the table is also not created.
+            let mut tx = con.transaction().map_err(Error::from)?;
+
+            tx.execute(
+                &format!(
+                    "CREATE TABLE {} (key SERIAL PRIMARY KEY, value JSONB NOT NULL);",
+                    Self::collection_name::<M>(),
+                ),
+                &[],
+            )
+            .map_err(Error::from)?;
+
+            // TODO: Create indexes
+
+            tx.commit().map_err(Error::from)?;
+        }
+
+        Ok(self.clone())
+    }
+}
+
+impl<M> super::Collection<&str, M> for Postgres
+where
+    M: Model,
+{
+    type Error = Error;
+
+    fn get<I, Q>(&self, key: &Q) -> Result<Vec<M>, super::Error<Self::Error>>
+    where
+        I: heromodels_core::Index<Model = M>,
+        I::Key: std::borrow::Borrow<Q>,
+        Q: ToString + ?Sized,
+    {
+        let mut con = self.pool.get().map_err(Error::from)?;
+
+        Ok(con
+            .query(
+                &format!(
+                    "SELECT (value) FROM {} WHERE value->$1 = $2;",
+                    Self::collection_name::<M>(),
+                ),
+                &[&I::key(), &key.to_string()],
+            )
+            .map_err(Error::from)?
+            .into_iter()
+            .map(|row| serde_json::from_str::<M>(row.get("value")).map_err(Error::from))
+            .collect::<Result<Vec<M>, _>>()?)
+    }
+
+    fn get_by_id(&self, id: u32) -> Result<Option<M>, super::Error<Self::Error>> {
+        let mut con = self.pool.get().map_err(Error::from)?;
+
+        if let Some(row) = con
+            .query(
+                &format!(
+                    "SELECT (value) FROM {} WHERE key = $1;",
+                    Self::collection_name::<M>()
+                ),
+                &[&id],
+            )
+            .map_err(Error::from)?
+            .into_iter()
+            .next()
+        {
+            Ok(Some(
+                serde_json::from_str::<M>(row.get("value")).map_err(Error::from)?,
+            ))
+        } else {
+            Ok(None)
+        }
+    }
+
+    fn set(&self, value: &M) -> Result<(u32, M), super::Error<Self::Error>> {
+        let mut con = self.pool.get().map_err(Error::from)?;
+
+        // let ser_val = serde_json::to_string(&value).map_err(Error::from)?;
+        let ser_val = jsonb::to_owned_jsonb(&value).map_err(Error::from)?;
+
+        if value.get_id() == 0 {
+            // NOTE: We perform a query here since we want the returned value which has the updated ID
+            let Some(row) = con
+                .query(
+                    &format!(
+                        "INSERT INTO {} (value) VALUES ($1) RETURNING key, value;",
+                        Self::collection_name::<M>()
+                    ),
+                    &[&postgres::types::Json(value)],
+                )
+                .map_err(Error::from)?
+                .into_iter()
+                .next()
+            else {
+                return Err(Error::FailedInsert.into());
+            };
+
+            eprintln!("insert done");
+
+            // Get the generated ID
+            let id = row.get::<_, i32>("key") as u32;
+            let mut value = row.get::<_, postgres::types::Json<M>>("value").0;
+            // .map_err(Error::from)?;
+            value.base_data_mut().id = id;
+
+            // NOTE: Update the value so the id is set correctly in the value itself
+            // let ser_val = serde_json::to_string(&value).map_err(Error::from)?;
+
+            let updated = con
+                .execute(
+                    &format!(
+                        "UPDATE {} SET value = $1 WHERE key = $2;",
+                        Self::collection_name::<M>()
+                    ),
+                    &[
+                        &postgres::types::Json(value.clone()),
+                        &(value.get_id() as i32),
+                    ],
+                )
+                .map_err(Error::from)?;
+
+            if updated != 1 {
+                return Err(Error::FailedUpdate(updated as usize).into());
+            }
+
+            Ok((id, value))
+        } else {
+            let updated = con
+                .execute(
+                    &format!(
+                        "UPDATE {} SET value = $1 WHERE key = $2;",
+                        Self::collection_name::<M>(),
+                    ),
+                    &[
+                        &postgres::types::Json(value.clone()),
+                        &(value.get_id() as i32),
+                    ],
+                )
+                .map_err(Error::from)?;
+
+            if updated != 1 {
+                return Err(Error::FailedUpdate(updated as usize).into());
+            }
+
+            Ok((value.get_id(), value.clone()))
+        }
+    }
+
+    fn delete<I, Q>(&self, key: &Q) -> Result<(), super::Error<Self::Error>>
+    where
+        I: heromodels_core::Index<Model = M>,
+        I::Key: std::borrow::Borrow<Q>,
+        Q: ToString + ?Sized,
+    {
+        let mut con = self.pool.get().map_err(Error::from)?;
+
+        con.execute(
+            &format!(
+                "DELETE FROM {} WHERE value->$1 = $2;",
+                Self::collection_name::<M>()
+            ),
+            &[&I::key(), &key.to_string()],
+        )
+        .map_err(Error::from)?;
+
+        Ok(())
+    }
+
+    fn delete_by_id(&self, id: u32) -> Result<(), super::Error<Self::Error>> {
+        let mut con = self.pool.get().map_err(Error::from)?;
+
+        con.execute(
+            &format!(
+                "DELETE FROM {} WHERE key = $1;",
+                Self::collection_name::<M>()
+            ),
+            &[&id],
+        )
+        .map_err(Error::from)?;
+
+        Ok(())
+    }
+
+    fn get_all(&self) -> Result<Vec<M>, super::Error<Self::Error>> {
+        let mut con = self.pool.get().map_err(Error::from)?;
+
+        Ok(con
+            .query(
+                &format!("SELECT (value) FROM {};", Self::collection_name::<M>()),
+                &[],
+            )
+            .map_err(Error::from)?
+            .into_iter()
+            .map(|row| serde_json::from_str::<M>(row.get("value")).map_err(Error::from))
+            .collect::<Result<Vec<M>, _>>()?)
+    }
+
+    fn begin_transaction(
+        &self,
+    ) -> Result<Box<dyn super::Transaction<Error = Self::Error>>, super::Error<Self::Error>> {
+        todo!()
+    }
+}
+
+impl core::fmt::Display for Error {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            Self::Postgres(e) => f.write_fmt(format_args!("postgres error: {e}")),
+            Self::ConnectionPool(e) => {
+                f.write_fmt(format_args!("postgres connection pool error: {e}"))
+            }
+            Self::Json(e) => {
+                f.write_fmt(format_args!("could not decode from or encode to json: {e}"))
+            }
+            Self::JsonB(e) => f.write_fmt(format_args!(
+                "could not decode from or encode to jsonb: {e}"
+            )),
+            Self::FailedInsert => f.write_str("insert did not return any result"),
+            Self::FailedUpdate(amount) => f.write_fmt(format_args!(
+                "update did not return the expected 1 modified row (got {amount})"
+            )),
+            Self::TableExistenceQuery => f.write_str("query to check if table exists failed"),
+        }
+    }
+}
+
+impl core::error::Error for Error {
+    fn source(&self) -> Option<&(dyn std::error::Error + 'static)> {
+        match self {
+            Self::Postgres(e) => Some(e),
+            Self::ConnectionPool(e) => Some(e),
+            Self::Json(e) => Some(e),
+            Self::JsonB(e) => Some(e),
+            _ => None,
+        }
+    }
+}
+
+impl From<postgres::error::Error> for Error {
+    fn from(value: postgres::error::Error) -> Self {
+        Self::Postgres(value)
+    }
+}
+
+impl From<r2d2::Error> for Error {
+    fn from(value: r2d2::Error) -> Self {
+        Self::ConnectionPool(value)
+    }
+}
+
+impl From<serde_json::Error> for Error {
+    fn from(value: serde_json::Error) -> Self {
+        Self::Json(value)
+    }
+}
+
+impl From<jsonb::Error> for Error {
+    fn from(value: jsonb::Error) -> Self {
+        Self::JsonB(value)
+    }
+}
+
+impl From<Error> for super::Error<Error> {
+    fn from(value: Error) -> Self {
+        super::Error::DB(value)
+    }
+}