wascc-logging 0.8.0

// Copyright 2015-2020 Capital One Services, LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#[macro_use]
extern crate wascc_codec as codec;

use codec::capabilities::{
    CapabilityDescriptor, CapabilityProvider, Dispatcher, NullDispatcher, OperationDirection,
    OP_GET_CAPABILITY_DESCRIPTOR,
};
use codec::core::{OP_BIND_ACTOR, OP_REMOVE_ACTOR};
use codec::{
    deserialize,
    logging::{WriteLogRequest, OP_LOG},
    serialize,
};

#[macro_use]
extern crate log;

use std::error::Error;
use std::sync::RwLock;

#[cfg(not(feature = "static_plugin"))]
capability_provider!(LoggingProvider, LoggingProvider::new);

const CAPABILITY_ID: &str = "wascc:logging";
const SYSTEM_ACTOR: &str = "system";
const VERSION: &str = env!("CARGO_PKG_VERSION");
const REVISION: u32 = 2; // Increment for each crates publish

const ERROR: u32 = 1;
const WARN: u32 = 2;
const INFO: u32 = 3;
const DEBUG: u32 = 4;
const TRACE: u32 = 5;

/// Standard output logging implementation of the `wascc:logging` specification
pub struct LoggingProvider {
    dispatcher: RwLock<Box<dyn Dispatcher>>,
}

impl Default for LoggingProvider {
    fn default() -> Self {
        match env_logger::try_init() {
            Ok(_) => {}
            Err(_) => {}
        }

        LoggingProvider {
            dispatcher: RwLock::new(Box::new(NullDispatcher::new())),
        }
    }
}

impl LoggingProvider {
    /// Creates a new logging provider
    pub fn new() -> Self {
        Self::default()
    }

    fn get_descriptor(&self) -> Result<Vec<u8>, Box<dyn Error + Sync + Send>> {
        Ok(serialize(
            CapabilityDescriptor::builder()
                .id(CAPABILITY_ID)
                .name("waSCC Default Logging Provider (STDOUT)")
                .long_description(
                    "A simple logging capability provider that supports levels from error to trace",
                )
                .version(VERSION)
                .revision(REVISION)
                .with_operation(
                    OP_LOG,
                    OperationDirection::ToProvider,
                    "Sends a log message to stdout",
                )
                .build(),
        )?)
    }

    fn write_log(
        &self,
        actor: &str,
        log_msg: WriteLogRequest,
    ) -> Result<Vec<u8>, Box<dyn Error + Sync + Send>> {
        match log_msg.level {
            ERROR => error!("[{}] {}", actor, log_msg.body),
            WARN => warn!("[{}] {}", actor, log_msg.body),
            INFO => info!("[{}] {}", actor, log_msg.body),
            DEBUG => debug!("[{}] {}", actor, log_msg.body),
            TRACE => trace!("[{}] {}", actor, log_msg.body),
            _ => error!("Unknown log level: {}", log_msg.level),
        }
        Ok(vec![])
    }
}

impl CapabilityProvider for LoggingProvider {
    // Invoked by the runtime host to give this provider plugin the ability to communicate
    // with actors
    fn configure_dispatch(
        &self,
        dispatcher: Box<dyn Dispatcher>,
    ) -> Result<(), Box<dyn Error + Sync + Send>> {
        let mut lock = self.dispatcher.write().unwrap();
        *lock = dispatcher;

        Ok(())
    }

    // Invoked by host runtime to allow an actor to make use of the capability
    // All providers MUST handle the "configure" message, even if no work will be done
    fn handle_call(
        &self,
        actor: &str,
        op: &str,
        msg: &[u8],
    ) -> Result<Vec<u8>, Box<dyn Error + Sync + Send>> {
        match op {
            OP_BIND_ACTOR if actor == SYSTEM_ACTOR => Ok(vec![]),
            OP_REMOVE_ACTOR if actor == SYSTEM_ACTOR => Ok(vec![]),
            OP_GET_CAPABILITY_DESCRIPTOR if actor == SYSTEM_ACTOR => self.get_descriptor(),
            OP_LOG => self.write_log(actor, deserialize(msg)?),
            _ => Err(format!("Unknown operation: {}", op).into()),
        }
    }
}