rmqtt-http-api 0.23.1

//! Shared types for the HTTP API plugin.
//!
//! Defines gRPC [`Message`] / [`MessageReply`] enums, API parameter structs
//! ([`ClientSearchParams`], [`PublishParams`], [`SubscribeParams`],
//! [`UnsubscribeParams`]), result types ([`ClientSearchResult`]), and
//! [`PrometheusDataType`].

use std::time::Duration;

use anyhow::anyhow;
use base64::prelude::{Engine, BASE64_STANDARD};
use serde::{de, ser, Deserialize, Serialize};

use rmqtt::types::NodeHealthStatus;
use rmqtt::{
    codec::v5::PublishProperties,
    metrics::Metrics,
    node::{BrokerInfo, NodeInfo, NodeStatus},
    plugin::PluginInfo,
    stats::Stats,
    types::{
        ClientId, From, HashMap, MsgID, NodeId, Publish, QoS, Retain, Timestamp, TopicFilter, TopicName,
        UserName,
    },
    utils::{deserialize_datetime_option, format_timestamp, serialize_datetime_option},
    Result,
};

/// gRPC messages for the HTTP API plugin.
///
/// Each variant corresponds to a request type that can be forwarded to
/// remote nodes.
#[derive(Serialize, Deserialize, Clone, Debug)]
pub enum Message<'a> {
    BrokerInfo,
    NodeInfo,
    NodeHealthStatus,
    StatsInfo,
    MetricsInfo,
    ClientSearch(Box<ClientSearchParams>),
    ClientGet {
        clientid: &'a str,
    },
    Subscribe(SubscribeParams),
    Unsubscribe(UnsubscribeParams),
    GetPlugins,
    GetPlugin {
        name: &'a str,
    },
    GetPluginConfig {
        name: &'a str,
    },
    ReloadPluginConfig {
        name: &'a str,
    },
    LoadPlugin {
        name: &'a str,
    },
    UnloadPlugin {
        name: &'a str,
    },
    // ── History query messages ─────────────────────────────────────────
    /// Query another node's Stats history
    StatsHistoryQuery(HistoryQuery),
    /// Query another node's Metrics history
    MetricsHistoryQuery(HistoryQuery),
    // ── Feature support query ──────────────────────────────────────────
    /// Query another node's supported features
    Features,
}

impl Message<'_> {
    /// Encodes this message into a byte vector using postcard.
    /// Encodes this message into a byte vector using postcard.
    #[inline]
    pub fn encode(&self) -> Result<Vec<u8>> {
        postcard::to_stdvec(self).map_err(anyhow::Error::new)
    }
    /// Decodes this message from a byte slice.
    #[inline]
    pub fn decode(data: &[u8]) -> Result<Message<'_>> {
        postcard::from_bytes::<Message>(data).map_err(anyhow::Error::new)
    }
}

/// gRPC reply messages for the HTTP API plugin.
#[derive(Serialize, Deserialize, Debug)]
pub enum MessageReply {
    BrokerInfo(BrokerInfo),
    NodeInfo(NodeInfo),
    NodeHealthStatus(NodeHealthStatus),
    StatsInfo(NodeStatus, Box<Stats>),
    MetricsInfo(Box<Metrics>),
    ClientSearch(Vec<ClientSearchResult>),
    ClientGet(Option<ClientSearchResult>),
    Subscribe(HashMap<TopicFilter, (bool, Option<String>)>),
    Unsubscribe,
    GetPlugins(Vec<PluginInfo>),
    GetPlugin(Option<PluginInfo>),
    GetPluginConfig(Vec<u8>),
    ReloadPluginConfig,
    LoadPlugin,
    UnloadPlugin(bool),
    // ── History query replies ──────────────────────────────────────────
    /// Stats history data from a node.
    ///
    /// The [`HistoryData`] is transported as its **JSON string** because
    /// postcard cannot deserialize `serde_json::Value` (it requires
    /// `deserialize_any`, which postcard explicitly does not implement).
    StatsHistoryReply(String),
    /// Metrics history data from a node (same JSON-string transport).
    MetricsHistoryReply(String),
    // ── Feature support reply ──────────────────────────────────────────
    /// Feature support state of a node.
    Features(FeaturesInfo),
}

impl MessageReply {
    /// Encodes this reply into a byte vector using postcard.
    /// Encodes this reply into a byte vector using postcard.
    #[inline]
    pub fn encode(&self) -> Result<Vec<u8>> {
        postcard::to_stdvec(self).map_err(anyhow::Error::new)
    }
    /// Decodes this reply from a byte slice.
    #[inline]
    pub fn decode(data: &[u8]) -> Result<MessageReply> {
        postcard::from_bytes::<MessageReply>(data).map_err(anyhow::Error::new)
    }
}

/// Search/filter parameters for listing clients via the HTTP API.
#[derive(Deserialize, Serialize, Debug, Clone, Default)]
pub struct ClientSearchParams {
    #[serde(default)]
    pub _limit: usize,
    pub clientid: Option<String>,
    pub username: Option<String>,
    pub ip_address: Option<String>,
    pub connected: Option<bool>,
    pub clean_start: Option<bool>,
    pub session_present: Option<bool>,
    pub proto_ver: Option<u8>,
    pub _like_clientid: Option<String>,
    //Substring fuzzy search
    pub _like_username: Option<String>,
    //Substring fuzzy search
    #[serde(
        default,
        deserialize_with = "deserialize_datetime_option",
        serialize_with = "serialize_datetime_option"
    )]
    pub _gte_created_at: Option<Duration>,
    //Greater than or equal search
    #[serde(
        default,
        deserialize_with = "deserialize_datetime_option",
        serialize_with = "serialize_datetime_option"
    )]
    pub _lte_created_at: Option<Duration>,
    //Less than or equal search
    #[serde(
        default,
        deserialize_with = "deserialize_datetime_option",
        serialize_with = "serialize_datetime_option"
    )]
    pub _gte_connected_at: Option<Duration>,
    //Greater than or equal search
    #[serde(
        default,
        deserialize_with = "deserialize_datetime_option",
        serialize_with = "serialize_datetime_option"
    )]
    pub _lte_connected_at: Option<Duration>,
    //Less than or equal search
    pub _gte_mqueue_len: Option<usize>,
    //Current length of message queue, Greater than or equal search
    pub _lte_mqueue_len: Option<usize>, //Current length of message queue, Less than or equal search
}

/// A single client's information returned by the search API.
#[derive(Deserialize, Serialize, Debug, Default)]
pub struct ClientSearchResult {
    pub node_id: NodeId,
    pub clientid: ClientId,
    pub username: UserName,
    pub superuser: bool,
    pub proto_ver: u8,
    pub ip_address: Option<String>,
    pub port: Option<u16>,
    pub connected: bool,
    pub connected_at: Timestamp,
    pub disconnected_at: Timestamp,
    pub disconnected_reason: String,
    pub keepalive: u16,
    pub clean_start: bool,
    pub session_present: bool,
    pub expiry_interval: i64,
    pub created_at: Timestamp,
    pub subscriptions_cnt: usize,
    pub max_subscriptions: usize,
    // pub extra_attrs: usize,
    #[serde(
        default,
        serialize_with = "ClientSearchResult::serialize_last_will",
        deserialize_with = "ClientSearchResult::deserialize_last_will"
    )]
    pub last_will: serde_json::Value,

    pub inflight: usize,
    pub max_inflight: u16,
    //    pub inflight_dropped: usize,
    pub mqueue_len: usize,
    pub max_mqueue: usize,
    //     pub mqueue_dropped: usize,

    //    pub awaiting_rel:0,
    //    pub max_awaiting_rel:s.listen_cfg.max_awaiting_rel,
    //    pub awaiting_rel_dropped:0,

    //     pub recv_msg:0,	//Number of received PUBLISH packets
    //     pub send_msg:0,	//Number of sent PUBLISH packets
    //     pub resend_msg:0, //Resent message data
    //     pub ackeds:0,  //Number of Acked received
}

impl ClientSearchResult {
    /// Serializes the last will as a JSON byte vector.
    #[inline]
    fn serialize_last_will<S>(last_will: &serde_json::Value, s: S) -> std::result::Result<S::Ok, S::Error>
    where
        S: ser::Serializer,
    {
        serde_json::to_vec(last_will).map_err(ser::Error::custom)?.serialize(s)
    }

    /// Deserializes the last will from a JSON byte vector.
    #[inline]
    pub fn deserialize_last_will<'de, D>(d: D) -> std::result::Result<serde_json::Value, D::Error>
    where
        D: de::Deserializer<'de>,
    {
        serde_json::from_slice(&Vec::deserialize(d)?).map_err(de::Error::custom)
    }

    /// Converts this search result to a JSON value for API responses.
    #[inline]
    pub fn to_json(&self) -> serde_json::Value {
        let data = serde_json::json!({
            "node_id": self.node_id,
            "clientid": self.clientid,
            "username": self.username,
            "superuser": self.superuser,
            "proto_ver": self.proto_ver,
            "ip_address": self.ip_address,
            "port": self.port,
            "connected": self.connected,
            "connected_at": format_timestamp(self.connected_at),
            "disconnected_at": format_timestamp(self.disconnected_at),
            "disconnected_reason": self.disconnected_reason,
            "keepalive": self.keepalive,
            "clean_start": self.clean_start,
            "session_present": self.session_present,
            "expiry_interval": self.expiry_interval,
            "created_at": format_timestamp(self.created_at),
            "subscriptions_cnt": self.subscriptions_cnt,
            "max_subscriptions": self.max_subscriptions,
            // "extra_attrs": self.extra_attrs,
            "last_will": self.last_will,

            "inflight": self.inflight,
            "max_inflight": self.max_inflight,
            //"inflight_dropped": 0,

            "mqueue_len": self.mqueue_len,
            "max_mqueue": self.max_mqueue,
            // "mqueue_dropped": 0,

            //"awaiting_rel": 0,
            //"max_awaiting_rel": s.listen_cfg.max_awaiting_rel,
            //"awaiting_rel_dropped": 0,

            // "recv_msg": 0,	//Number of received PUBLISH packets
            // "send_msg": 0,	//Number of sent PUBLISH packets
            // "resend_msg": 0, //Resent message data
            // "ackeds": 0,  //Number of Acked received

        });
        data
    }
}

/// Parameters for publishing an MQTT message via the HTTP API.
#[derive(Deserialize, Serialize, Debug, Clone, Default)]
pub struct PublishParams {
    //For topic and topics, with at least one of them specified
    pub topic: Option<TopicName>,
    //Multiple topics separated by ,. This field is used to publish messages to multiple topics at the same time
    pub topics: Option<TopicName>,
    //Client identifier. Default:　system
    #[serde(default = "PublishParams::clientid_default")]
    pub clientid: ClientId,
    //Message body
    pub payload: String,
    //The encoding used in the message body. Currently only plain and base64 are supported. Default:　plain
    #[serde(default = "PublishParams::encoding_default")]
    pub encoding: String,
    //QoS level, Default: 0
    #[serde(default = "PublishParams::qos_default")]
    pub qos: u8,
    //Whether it is a retained message, Default: false
    #[serde(default = "PublishParams::retain_default")]
    pub retain: bool,
    //Publish Properties
    pub properties: Option<PublishProperties>,
}

impl PublishParams {
    fn clientid_default() -> ClientId {
        "system".into()
    }

    fn encoding_default() -> String {
        "plain".into()
    }

    fn qos_default() -> u8 {
        0
    }

    fn retain_default() -> bool {
        false
    }
}

/// Parameters for subscribing to MQTT topics via the HTTP API.
#[derive(Deserialize, Serialize, Debug, Clone, Default)]
pub struct SubscribeParams {
    //For topic and topics, with at least one of them specified
    pub topic: Option<TopicFilter>,
    //Multiple topics separated by,. This field is used to subscribe to multiple topics at the same time
    pub topics: Option<TopicFilter>,
    //Client identifier, Required
    pub clientid: ClientId,
    //QoS level, Default: 0
    #[serde(default = "SubscribeParams::qos_default")]
    pub qos: u8,
}

impl SubscribeParams {
    fn qos_default() -> u8 {
        0
    }

    /// Returns the list of topic filters from the `topic` and/or `topics`
    /// fields.
    /// Returns the list of topic filters from the `topic` and/or `topics`
    /// fields.
    #[inline]
    pub fn topics(&self) -> Result<Vec<TopicFilter>> {
        let mut topics = if let Some(topics) = &self.topics {
            topics.split(',').collect::<Vec<_>>().iter().map(|t| TopicName::from(t.trim())).collect()
        } else {
            Vec::new()
        };
        if let Some(topic) = &self.topic {
            topics.push(topic.clone());
        }
        if topics.is_empty() {
            return Err(anyhow!("topics or topic is empty"));
        }
        Ok(topics)
    }

    /// Returns the QoS level parsed from the raw u8 value.
    #[inline]
    pub fn qos(&self) -> Result<QoS> {
        QoS::try_from(self.qos).map_err(|e| anyhow!(e))
    }
}

/// Parameters for unsubscribing from an MQTT topic via the HTTP API.
#[derive(Deserialize, Serialize, Debug, Clone, Default)]
pub struct UnsubscribeParams {
    pub topic: TopicFilter,
    pub clientid: ClientId,
}

/// Feature support state of a single node.
#[derive(Serialize, Deserialize, Clone, Debug, Default)]
pub struct FeaturesInfo {
    pub node_id: NodeId,
    pub node_name: String,
    pub features: Features,
}

/// Runtime capability flags of a broker node.
///
/// A feature is `true` when the backing implementation is loaded and
/// enabled at runtime (e.g. the corresponding plugin is started).
#[derive(Serialize, Deserialize, Clone, Debug, Default)]
pub struct Features {
    /// Retained messages (`rmqtt-retainer` plugin).
    pub retain: bool,
    /// Persistent message storage (`rmqtt-message-storage` plugin).
    pub message_storage: bool,
    /// Persistent session storage (`rmqtt-session-storage` plugin).
    pub session_storage: bool,
    /// Delayed message publishing (`$delayed/...` topics).
    pub delayed: bool,
    /// Shared subscriptions `$share` (`rmqtt-shared-subscription` plugin).
    pub shared_subscription: bool,
    /// Automatic subscriptions (`rmqtt-auto-subscription` plugin).
    pub auto_subscription: bool,
}

/// Aggregated feature support state across all cluster nodes.
///
/// `consistent` is `false` when at least one feature field differs between
/// nodes; the differing fields are reported in `conflicts` so operators can
/// locate mis-configured / partially-failed nodes.
#[derive(Serialize, Deserialize, Clone, Debug, Default)]
pub struct FeaturesSummary {
    /// Whether all successfully-reached nodes report identical feature flags.
    pub consistent: bool,
    /// Number of nodes that successfully reported their features.
    pub node_count: usize,
    /// Feature fields whose values differ across nodes (empty when `consistent`).
    #[serde(skip_serializing_if = "Vec::is_empty")]
    pub conflicts: Vec<FeatureConflict>,
    /// Per-node feature details. Unreachable nodes are represented as an
    /// error string and do not participate in the consistency check.
    pub nodes: Vec<FeaturesInfoOrError>,
}

/// A feature field whose reported value differs across cluster nodes.
#[derive(Serialize, Deserialize, Clone, Debug)]
pub struct FeatureConflict {
    pub feature: String,
    /// Nodes grouped by their reported value of this feature field.
    pub values: Vec<FeatureValueGroup>,
}

/// Nodes that reported the same value for a conflicting feature field.
#[derive(Serialize, Deserialize, Clone, Debug)]
pub struct FeatureValueGroup {
    pub value: bool,
    pub node_ids: Vec<NodeId>,
}

/// Per-node entry of the features summary: either the feature state of a
/// reachable node, or an error string for an unreachable one.
#[derive(Serialize, Deserialize, Clone, Debug)]
#[serde(untagged)]
pub enum FeaturesInfoOrError {
    Info(FeaturesInfo),
    Error(String),
}

/// Query parameters for listing retained messages.
///
/// - When `topic_filter` is empty or `#`, the storage backend's paginated
///   snapshot is used directly (`RetainStorage::get_all_paginated`), which
///   includes the remaining TTL of each message.
/// - Otherwise all messages matching the filter are fetched via
///   `RetainStorage::get` and paginated in memory (no TTL information).
#[derive(Deserialize, Serialize, Debug, Clone, Default)]
pub struct RetainQueryParams {
    /// Topic filter, supports `#` / `+` wildcards. Default: `#` (all messages).
    #[serde(default = "RetainQueryParams::topic_filter_default")]
    pub topic_filter: TopicFilter,
    /// Pagination offset. Default: 0.
    #[serde(default)]
    pub offset: usize,
    /// Page size. `0` or values above `max_row_limit` are capped by the caller.
    #[serde(default)]
    pub limit: usize,
}

impl RetainQueryParams {
    fn topic_filter_default() -> TopicFilter {
        "#".into()
    }
}

/// A single retained message entry returned by the HTTP API.
#[derive(Serialize, Deserialize, Debug)]
pub struct RetainInfo {
    pub topic: TopicName,
    pub msg_id: Option<MsgID>,
    pub from: From,
    pub publish: RetainPublishInfo,
    /// Remaining time-to-live in seconds. `null` when the storage backend
    /// does not expose TTL information (the topic-filtered `get()` path).
    #[serde(skip_serializing_if = "Option::is_none")]
    pub remaining_ttl: Option<u64>,
    /// Client ID of the publisher, extracted from `from.id.client_id`.
    #[serde(skip_serializing_if = "Option::is_none")]
    pub client_id: Option<String>,
}

impl RetainInfo {
    /// Build an entry from a `(TopicName, Retain)` pair (no TTL info).
    #[inline]
    pub fn from_get(topic: TopicName, retain: Retain) -> Self {
        Self {
            topic,
            msg_id: retain.msg_id,
            from: retain.from.clone(),
            publish: RetainPublishInfo::from_publish(retain.publish),
            remaining_ttl: None,
            client_id: publisher_client_id(&retain.from),
        }
    }

    /// Build an entry from a `(TopicName, Retain, Option<Duration>)` triple.
    #[inline]
    pub fn from_paginated(topic: TopicName, retain: Retain, remaining: Option<Duration>) -> Self {
        Self {
            topic,
            msg_id: retain.msg_id,
            from: retain.from.clone(),
            publish: RetainPublishInfo::from_publish(retain.publish),
            remaining_ttl: remaining.map(|d| d.as_secs()),
            client_id: publisher_client_id(&retain.from),
        }
    }
}

/// Extract the publisher client ID from a `From` (empty -> `None`).
#[inline]
fn publisher_client_id(from: &From) -> Option<String> {
    let client_id = from.id.client_id.to_string();
    if client_id.is_empty() {
        None
    } else {
        Some(client_id)
    }
}

/// Serialized form of a retained publish packet for the HTTP API response.
#[derive(Serialize, Deserialize, Debug)]
pub struct RetainPublishInfo {
    pub topic: TopicName,
    pub qos: u8,
    pub retain: bool,
    pub dup: bool,
    /// Message payload encoded as base64.
    pub payload: String,
    pub create_time: Option<i64>,
    pub properties: Option<PublishProperties>,
}

impl RetainPublishInfo {
    #[inline]
    fn from_publish(p: Publish) -> Self {
        let inner = p.inner;
        Self {
            topic: inner.topic,
            qos: inner.qos as u8,
            retain: inner.retain,
            dup: inner.dup,
            payload: BASE64_STANDARD.encode(inner.payload.as_ref()),
            create_time: p.create_time,
            properties: inner.properties,
        }
    }
}

/// Specifies which nodes' Prometheus data to include.
///
/// - `All`: data from every node.
/// - `Sum`: aggregated sum across all nodes.
/// - `Node(id)`: data from a specific node.
#[derive(Deserialize, Serialize, Debug, Copy, Clone, Hash, Eq, PartialEq)]
pub enum PrometheusDataType {
    All,
    Node(NodeId),
    Sum,
}

/// Query parameters for fetching history data from a remote node via gRPC.
#[derive(Serialize, Deserialize, Debug, Clone)]
pub struct HistoryQuery {
    /// Start timestamp (milliseconds, inclusive)
    pub start_ts: u64,
    /// End timestamp (milliseconds, inclusive)
    pub end_ts: u64,
    /// Maximum number of data points to return
    pub limit: usize,
    /// Merge window in seconds — returns data merged at this granularity.
    /// When `None`, uses the node's `flush_interval`.
    pub merge_window: Option<u64>,
}

/// History data returned by a node for a history query.
#[derive(Serialize, Deserialize, Debug, Clone)]
pub struct HistoryData {
    /// Node that produced this data
    pub node: NodeId,
    /// Start of the query window
    pub from: u64,
    /// End of the query window
    pub to: u64,
    /// Number of data points returned
    pub count: usize,
    /// JSON data points, each is a flattened Stats/Metrics snapshot
    /// with a "ts" field for the timestamp.
    pub data: Vec<serde_json::Value>,
}

// #[inline]
// fn format_timestamp(t: i64) -> String {
//     if t <= 0 {
//         "".into()
//     } else {
//         use chrono::TimeZone;
//         if let LocalResult::Single(t) = chrono::Local.timestamp_opt(t, 0) {
//             t.format("%Y-%m-%d %H:%M:%S").to_string()
//         } else {
//             "".into()
//         }
//     }
// }

// ════════════════════════════════════════════════════════════════════════
//  LRU Cache types for history optimisation
// ════════════════════════════════════════════════════════════════════════

/// Bit flags for cache entry persistence state.
#[derive(Clone, Copy, Debug, PartialEq, Eq)]
pub(crate) struct EntryFlags(u8);

impl EntryFlags {
    pub const NONE: u8 = 0b00;
    pub const PENDING: u8 = 0b01;
    pub const FAILED: u8 = 0b10;

    #[inline]
    pub const fn new(bits: u8) -> Self {
        Self(bits)
    }

    #[inline]
    #[allow(dead_code)]
    pub fn is_pending(self) -> bool {
        self.0 & Self::PENDING != 0
    }
    #[inline]
    #[allow(dead_code)]
    pub fn is_failed(self) -> bool {
        self.0 & Self::FAILED != 0
    }

    /// Returns `true` if the entry needs recovery attention (has FAILED bit set).
    #[inline]
    pub fn needs_recovery(self) -> bool {
        self.0 & Self::FAILED != 0
    }
}

/// A single history data point in the LRU cache.
#[derive(Clone, Debug)]
pub(crate) struct CacheEntry {
    /// JSON-serialised Stats or Metrics snapshot.
    pub json: String,
    /// Persistence state flags.
    pub flags: EntryFlags,
}

impl CacheEntry {
    #[inline]
    pub fn new(json: String) -> Self {
        Self { json, flags: EntryFlags::new(EntryFlags::PENDING) }
    }
}