kotoba-projection-engine 0.1.21

Real-time projection engine for GraphDB materialization using RocksDB
Documentation
//! View Manager
//!
//! Manages materialized views and projections in the GraphDB.

use std::collections::HashMap;
use std::sync::Arc;
use async_trait::async_trait;
use serde::{Deserialize, Serialize};
use anyhow::Result;
use tracing::{info, warn, error, instrument};

use crate::ProjectionDefinition;

/// View manager for handling materialized views
pub struct ViewManager {
    /// Active views
    views: HashMap<String, ViewDefinition>,
}

/// View definition
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct ViewDefinition {
    pub name: String,
    pub definition: ProjectionDefinition,
    pub created_at: chrono::DateTime<chrono::Utc>,
    pub last_updated: chrono::DateTime<chrono::Utc>,
}

impl ViewManager {
    /// Create a new view manager
    pub fn new() -> Self {
        Self {
            views: HashMap::new(),
        }
    }

    /// Create a new projection
    #[instrument(skip(self))]
    pub async fn create_projection(&self, name: String, definition: ProjectionDefinition) -> Result<()> {
        info!("Creating projection: {}", name);

        let view_def = ViewDefinition {
            name: name.clone(),
            definition,
            created_at: chrono::Utc::now(),
            last_updated: chrono::Utc::now(),
        };

        // TODO: Persist view definition to storage
        // For now, just store in memory
        // self.views.insert(name.clone(), view_def);

        info!("Projection created: {}", name);
        Ok(())
    }

    /// Delete a projection
    #[instrument(skip(self))]
    pub async fn delete_projection(&self, name: &str) -> Result<()> {
        info!("Deleting projection: {}", name);

        // TODO: Remove from storage
        // self.views.remove(name);

        info!("Projection deleted: {}", name);
        Ok(())
    }

    /// List all projections
    pub async fn list_projections(&self) -> Result<Vec<String>> {
        // TODO: Load from storage
        Ok(vec![])
    }

    /// Get projection definition
    pub async fn get_projection(&self, name: &str) -> Result<Option<ViewDefinition>> {
        // TODO: Load from storage
        Ok(None)
    }
}

impl Default for ViewManager {
    fn default() -> Self {
        Self::new()
    }
}