Initial commit

.gitignore

@@ -8,3 +8,8 @@ Cargo.lock
 
 # These are backup files generated by rustfmt
 **/*.rs.bk
+
+
+# Added by cargo
+
+/target

Cargo.toml

@@ -0,0 +1,15 @@
+[package]
+name = "aqua-dht"
+version = "0.1.0"
+authors = ["Fluence Labs"]
+edition = "2018"
+publish = false
+
+[[bin]]
+name = "aqua-dht"
+path = "src/main.rs"
+
+[dependencies]
+fluence = "0.5.0"
+fce-sqlite-connector = "0.3.0"
+fstrings = "0.2.3"

Config.toml

@@ -0,0 +1,19 @@
+modules_dir = "artifacts/"
+
+[[module]]
+    name = "sqlite3"
+    mem_pages_count = 100
+    logger_enabled = false
+
+    [module.wasi]
+    preopened_files = ["/tmp"]
+    mapped_dirs = { "tmp" = "/tmp" }
+
+[[module]]
+    name = "aqua-dht"
+    mem_pages_count = 1
+    logger_enabled = false
+
+    [module.wasi]
+    preopened_files = ["/tmp"]
+    mapped_dirs = { "tmp" = "/tmp" }

build.sh

@@ -0,0 +1,10 @@
+#!/usr/bin/env bash -o errexit -o nounset -o pipefail
+
+# This script builds all subprojects and puts all created Wasm modules in one dir
+cargo update
+fce build --release
+
+rm -f artifacts/*
+mkdir -p artifacts
+cp target/wasm32-wasi/release/aqua-dht.wasm artifacts/
+curl -L https://github.com/fluencelabs/sqlite/releases/download/v0.10.0_w/sqlite3.wasm -o artifacts/sqlite3.wasm

src/main.rs

@@ -0,0 +1,121 @@
+use fluence::fce;
+use fluence::module_manifest;
+
+use fce_sqlite_connector;
+use fce_sqlite_connector::{Value, Connection};
+
+#[macro_use]
+extern crate fstrings;
+
+module_manifest!();
+
+pub static TABLE_NAME: &str = "dht";
+pub static DB_PATH: &str = "/tmp/dht.db";
+pub static STALE_VALUE_AGE: u64 = 60 * 60 * 1000;
+pub static EXPIRED_VALUE_AGE: u64 = 24 * 60 * 60 * 1000;
+
+#[inline]
+fn get_connection() -> Connection{
+    fce_sqlite_connector::open(DB_PATH).unwrap()
+}
+
+#[fce]
+pub fn create_table(table_name: String) -> bool {
+    let connection = get_connection();
+
+    connection
+        .execute(f!("
+            CREATE TABLE IF NOT EXISTS {table_name} (
+                key TEXT PRIMARY KEY,
+                value TEXT,
+                timestamp INTEGER,
+                peer_id TEXT);
+        "),
+        ).is_ok()
+}
+
+fn main() {
+    create_table(TABLE_NAME.to_string());
+}
+
+#[fce]
+pub fn put_value(key: String, value: String, timestamp: u64) -> bool {
+    let connection = get_connection();
+    let peer_id = fluence::get_call_parameters().init_peer_id;
+
+    let statement = f!("
+            INSERT OR REPLACE INTO {TABLE_NAME} VALUES ('{key}', '{value}', {timestamp}, '{peer_id}');
+        ");
+    println!("{}", statement);
+    connection.execute(statement).is_ok()
+}
+
+#[fce]
+#[derive(Debug)]
+pub struct GetValueResult {
+    pub success: bool,
+    pub result: String,
+}
+
+#[fce]
+pub fn get_value(key: String) -> GetValueResult {
+    let connection = get_connection();
+
+    let mut cursor = connection
+        .prepare(f!("SELECT value FROM {TABLE_NAME} WHERE key = ?"))
+        .unwrap()
+        .cursor();
+
+    cursor.bind(&[Value::String(key)]).unwrap();
+    if let Some(row) = cursor.next().unwrap() {
+        GetValueResult { success: true, result: row[0].as_string().expect("error on row[0] parsing").to_string() }
+    } else {
+        GetValueResult { success: false, result: "not found".to_string() }
+    }
+}
+
+#[fce]
+pub fn clear_expired(current_timestamp: u64) -> u64 {
+    let connection = get_connection();
+
+    let expired_timestamp = current_timestamp - EXPIRED_VALUE_AGE;
+    connection
+        .execute(f!("DELETE FROM {TABLE_NAME} WHERE timestamp <= {expired_timestamp}"))
+        .unwrap();
+
+    connection.changes() as u64
+}
+
+#[fce]
+#[derive(Debug)]
+pub struct Record {
+    pub key: String,
+    pub value: String,
+    pub peer_id: String,
+}
+
+#[fce]
+pub fn get_stale_records(current_timestamp: u64) -> Vec<Record> {
+    let connection = get_connection();
+
+    let expired_timestamp = current_timestamp.saturating_sub(EXPIRED_VALUE_AGE);
+    let stale_timestamp = current_timestamp.saturating_sub(STALE_VALUE_AGE);
+
+    let statement = f!("SELECT key, value, peer_id FROM {TABLE_NAME} WHERE timestamp BETWEEN {expired_timestamp} AND {stale_timestamp}");
+    println!("{}", statement);
+    let mut cursor = connection
+        .prepare(statement)
+        .unwrap()
+        .cursor();
+
+    let mut result: Vec<Record> = Vec::new();
+    while let Some(row) = cursor.next().unwrap() {
+        let key = row[0].as_string().expect("error on key parsing").to_string();
+        let value = row[1].as_string().expect("error on value parsing").to_string();
+        let peer_id = row[2].as_string().expect("error on peer_id parsing").to_string();
+
+        result.push(Record { key, value, peer_id });
+    }
+
+    result
+}