From 0d9bf4f2e785cf09042b3e147d18a5c7462929ee Mon Sep 17 00:00:00 2001
From: "Bernardo A. Rodrigues" <bernardo@parity.io>
Date: Mon, 20 Jun 2022 19:01:14 -0300
Subject: [PATCH 1/8] allow custom gossipsub protocol id

---
 protocols/gossipsub/src/behaviour.rs | 23 ++++++++++++++------
 protocols/gossipsub/src/config.rs    | 29 ++++++++++++++++++++++---
 protocols/gossipsub/src/handler.rs   | 32 ++++++++++++++++++++++++++++
 protocols/gossipsub/src/protocol.rs  | 23 +++++++++++++++++---
 protocols/gossipsub/src/types.rs     |  3 +++
 5 files changed, 97 insertions(+), 13 deletions(-)

diff --git a/protocols/gossipsub/src/behaviour.rs b/protocols/gossipsub/src/behaviour.rs
index ea8bd73b89a..ec99621714f 100644
--- a/protocols/gossipsub/src/behaviour.rs
+++ b/protocols/gossipsub/src/behaviour.rs
@@ -3056,13 +3056,22 @@ where
     type OutEvent = GossipsubEvent;
 
     fn new_handler(&mut self) -> Self::ConnectionHandler {
-        GossipsubHandler::new(
-            self.config.protocol_id_prefix().clone(),
-            self.config.max_transmit_size(),
-            self.config.validation_mode().clone(),
-            self.config.idle_timeout(),
-            self.config.support_floodsub(),
-        )
+        if self.config.support_custom() {
+            GossipsubHandler::new_custom(
+                self.config.custom_protocol_id().clone(),
+                self.config.max_transmit_size(),
+                self.config.validation_mode().clone(),
+                self.config.idle_timeout(),
+            )
+        } else {
+            GossipsubHandler::new(
+                self.config.protocol_id_prefix().clone(),
+                self.config.max_transmit_size(),
+                self.config.validation_mode().clone(),
+                self.config.idle_timeout(),
+                self.config.support_floodsub(),
+            )
+        }
     }
 
     fn inject_connection_established(
diff --git a/protocols/gossipsub/src/config.rs b/protocols/gossipsub/src/config.rs
index e2758cd45da..ee700b252d2 100644
--- a/protocols/gossipsub/src/config.rs
+++ b/protocols/gossipsub/src/config.rs
@@ -53,6 +53,7 @@ pub enum ValidationMode {
 #[derive(Clone)]
 pub struct GossipsubConfig {
     protocol_id_prefix: Cow<'static, str>,
+    custom_protocol_id: Cow<'static, str>,
     history_length: usize,
     history_gossip: usize,
     mesh_n: usize,
@@ -90,6 +91,7 @@ pub struct GossipsubConfig {
     max_ihave_messages: usize,
     iwant_followup_time: Duration,
     support_floodsub: bool,
+    support_custom: bool,
     published_message_ids_cache_time: Duration,
 }
 
@@ -105,6 +107,11 @@ impl GossipsubConfig {
         &self.protocol_id_prefix
     }
 
+    /// The custom protocol id. It is optional and will replace anything that is set on protocol_id_prefix.
+    pub fn custom_protocol_id(&self) -> &Cow<'static, str> {
+        &self.custom_protocol_id
+    }
+
     // Overlay network parameters.
     /// Number of heartbeats to keep in the `memcache` (default is 5).
     pub fn history_length(&self) -> usize {
@@ -370,6 +377,11 @@ impl GossipsubConfig {
         self.support_floodsub
     }
 
+    /// Enable support for custom Gossipsub Protocol IDs. Default false.
+    pub fn support_custom(&self) -> bool {
+        self.support_custom
+    }
+
     /// Published message ids time cache duration. The default is 10 seconds.
     pub fn published_message_ids_cache_time(&self) -> Duration {
         self.published_message_ids_cache_time
@@ -395,6 +407,7 @@ impl Default for GossipsubConfigBuilder {
         GossipsubConfigBuilder {
             config: GossipsubConfig {
                 protocol_id_prefix: Cow::Borrowed("meshsub"),
+                custom_protocol_id: Cow::Borrowed(""),
                 history_length: 5,
                 history_gossip: 3,
                 mesh_n: 6,
@@ -444,6 +457,7 @@ impl Default for GossipsubConfigBuilder {
                 max_ihave_messages: 10,
                 iwant_followup_time: Duration::from_secs(3),
                 support_floodsub: false,
+                support_custom: false,
                 published_message_ids_cache_time: Duration::from_secs(10),
             },
         }
@@ -457,9 +471,16 @@ impl From<GossipsubConfig> for GossipsubConfigBuilder {
 }
 
 impl GossipsubConfigBuilder {
-    /// The protocol id to negotiate this protocol (default is `/meshsub/1.0.0`).
-    pub fn protocol_id_prefix(&mut self, protocol_id: impl Into<Cow<'static, str>>) -> &mut Self {
-        self.config.protocol_id_prefix = protocol_id.into();
+    /// The protocol id prefix to negotiate this protocol (default is `/meshsub/1.0.0`).
+    pub fn protocol_id_prefix(&mut self, protocol_id_prefix: impl Into<Cow<'static, str>>) -> &mut Self {
+        self.config.protocol_id_prefix = protocol_id_prefix.into();
+        self
+    }
+
+    /// The custom protocol id to negotiate this protocol (overrides any prefix set via `protocol_id_prefix`)
+    pub fn protocol_id(&mut self, protocol_id: impl Into<Cow<'static, str>>) -> &mut Self {
+        self.config.support_custom = true;
+        self.config.custom_protocol_id = protocol_id.into();
         self
     }
 
@@ -811,6 +832,7 @@ impl std::fmt::Debug for GossipsubConfig {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         let mut builder = f.debug_struct("GossipsubConfig");
         let _ = builder.field("protocol_id_prefix", &self.protocol_id_prefix);
+        let _ = builder.field("custom_protocol_id", &self.custom_protocol_id);
         let _ = builder.field("history_length", &self.history_length);
         let _ = builder.field("history_gossip", &self.history_gossip);
         let _ = builder.field("mesh_n", &self.mesh_n);
@@ -842,6 +864,7 @@ impl std::fmt::Debug for GossipsubConfig {
         let _ = builder.field("max_ihave_messages", &self.max_ihave_messages);
         let _ = builder.field("iwant_followup_time", &self.iwant_followup_time);
         let _ = builder.field("support_floodsub", &self.support_floodsub);
+        let _ = builder.field("support_custom", &self.support_custom);
         let _ = builder.field(
             "published_message_ids_cache_time",
             &self.published_message_ids_cache_time,
diff --git a/protocols/gossipsub/src/handler.rs b/protocols/gossipsub/src/handler.rs
index c0034f09712..040586d98f5 100644
--- a/protocols/gossipsub/src/handler.rs
+++ b/protocols/gossipsub/src/handler.rs
@@ -195,6 +195,38 @@ impl GossipsubHandler {
             in_mesh: false,
         }
     }
+
+    /// Builds a new [`GossipsubHandler`] with a custom Protocol ID
+    pub fn new_custom(
+        protocol_id: std::borrow::Cow<'static, str>,
+        max_transmit_size: usize,
+        validation_mode: ValidationMode,
+        idle_timeout: Duration,
+    ) -> Self {
+        GossipsubHandler {
+            listen_protocol: SubstreamProtocol::new(
+                ProtocolConfig::new_custom(
+                    protocol_id,
+                    max_transmit_size,
+                    validation_mode,
+                ),
+                (),
+            ),
+            inbound_substream: None,
+            outbound_substream: None,
+            outbound_substream_establishing: false,
+            outbound_substreams_created: 0,
+            inbound_substreams_created: 0,
+            send_queue: SmallVec::new(),
+            peer_kind: None,
+            peer_kind_sent: false,
+            protocol_unsupported: false,
+            idle_timeout,
+            upgrade_errors: VecDeque::new(),
+            keep_alive: KeepAlive::Until(Instant::now() + Duration::from_secs(INITIAL_KEEP_ALIVE)),
+            in_mesh: false,
+        }
+    }
 }
 
 impl ConnectionHandler for GossipsubHandler {
diff --git a/protocols/gossipsub/src/protocol.rs b/protocols/gossipsub/src/protocol.rs
index 72c985f2534..659e2ade6b3 100644
--- a/protocols/gossipsub/src/protocol.rs
+++ b/protocols/gossipsub/src/protocol.rs
@@ -81,6 +81,22 @@ impl ProtocolConfig {
             validation_mode,
         }
     }
+
+    pub fn new_custom(
+        protocol_id: Cow<'static, str>,
+        max_transmit_size: usize,
+        validation_mode: ValidationMode
+    ) -> ProtocolConfig {
+        let protocol_ids = vec![
+            ProtocolId::new(protocol_id, PeerKind::Custom),
+        ];
+
+        ProtocolConfig {
+            protocol_ids,
+            max_transmit_size,
+            validation_mode,
+        }
+    }
 }
 
 /// The protocol ID
@@ -94,11 +110,12 @@ pub struct ProtocolId {
 
 /// An RPC protocol ID.
 impl ProtocolId {
-    pub fn new(prefix: Cow<'static, str>, kind: PeerKind) -> Self {
+    pub fn new(prefix_or_custom: Cow<'static, str>, kind: PeerKind) -> Self {
         let protocol_id = match kind {
-            PeerKind::Gossipsubv1_1 => format!("/{}/{}", prefix, "1.1.0"),
-            PeerKind::Gossipsub => format!("/{}/{}", prefix, "1.0.0"),
+            PeerKind::Gossipsubv1_1 => format!("/{}/{}", prefix_or_custom, "1.1.0"),
+            PeerKind::Gossipsub => format!("/{}/{}", prefix_or_custom, "1.0.0"),
             PeerKind::Floodsub => format!("/{}/{}", "floodsub", "1.0.0"),
+            PeerKind::Custom => format!("{}", prefix_or_custom),
             // NOTE: This is used for informing the behaviour of unsupported peers. We do not
             // advertise this variant.
             PeerKind::NotSupported => unreachable!("Should never advertise NotSupported"),
diff --git a/protocols/gossipsub/src/types.rs b/protocols/gossipsub/src/types.rs
index 6ffde514e37..41506b257a4 100644
--- a/protocols/gossipsub/src/types.rs
+++ b/protocols/gossipsub/src/types.rs
@@ -103,6 +103,8 @@ pub enum PeerKind {
     Gossipsub,
     /// A floodsub peer.
     Floodsub,
+    /// A custom gossipsub peer.
+    Custom,
     /// The peer doesn't support any of the protocols.
     NotSupported,
 }
@@ -372,6 +374,7 @@ impl PeerKind {
     pub fn as_static_ref(&self) -> &'static str {
         match self {
             Self::NotSupported => "Not Supported",
+            Self::Custom => "Custom",
             Self::Floodsub => "Floodsub",
             Self::Gossipsub => "Gossipsub v1.0",
             Self::Gossipsubv1_1 => "Gossipsub v1.1",

From 1440425f8b199366a94b8726834a41e0fc9ef5cf Mon Sep 17 00:00:00 2001
From: "Bernardo A. Rodrigues" <bernardo@parity.io>
Date: Sat, 25 Jun 2022 16:36:58 -0300
Subject: [PATCH 2/8] pass config to new_handler

---
 protocols/gossipsub/src/behaviour.rs | 33 ++++++++++----------
 protocols/gossipsub/src/handler.rs   | 45 ++--------------------------
 protocols/gossipsub/src/protocol.rs  | 45 +++++++++++-----------------
 3 files changed, 36 insertions(+), 87 deletions(-)

diff --git a/protocols/gossipsub/src/behaviour.rs b/protocols/gossipsub/src/behaviour.rs
index ec99621714f..ae5df864491 100644
--- a/protocols/gossipsub/src/behaviour.rs
+++ b/protocols/gossipsub/src/behaviour.rs
@@ -54,7 +54,7 @@ use crate::handler::{GossipsubHandler, GossipsubHandlerIn, HandlerEvent};
 use crate::mcache::MessageCache;
 use crate::metrics::{Churn, Config as MetricsConfig, Inclusion, Metrics, Penalty};
 use crate::peer_score::{PeerScore, PeerScoreParams, PeerScoreThresholds, RejectReason};
-use crate::protocol::SIGNING_PREFIX;
+use crate::protocol::{SIGNING_PREFIX, ProtocolConfig};
 use crate::subscription_filter::{AllowAllSubscriptionFilter, TopicSubscriptionFilter};
 use crate::time_cache::{DuplicateCache, TimeCache};
 use crate::topic::{Hasher, Topic, TopicHash};
@@ -3056,22 +3056,21 @@ where
     type OutEvent = GossipsubEvent;
 
     fn new_handler(&mut self) -> Self::ConnectionHandler {
-        if self.config.support_custom() {
-            GossipsubHandler::new_custom(
-                self.config.custom_protocol_id().clone(),
-                self.config.max_transmit_size(),
-                self.config.validation_mode().clone(),
-                self.config.idle_timeout(),
-            )
-        } else {
-            GossipsubHandler::new(
-                self.config.protocol_id_prefix().clone(),
-                self.config.max_transmit_size(),
-                self.config.validation_mode().clone(),
-                self.config.idle_timeout(),
-                self.config.support_floodsub(),
-            )
-        }
+        let protocol_config = ProtocolConfig::new(
+            match self.config.support_custom() {
+                true => self.config.custom_protocol_id().clone(),
+                false => self.config.protocol_id_prefix().clone(),
+            },
+            self.config.max_transmit_size(),
+            self.config.validation_mode().clone(),
+            self.config.support_floodsub(),
+            self.config.support_custom(),
+        );
+
+        GossipsubHandler::new(
+            protocol_config,
+            self.config.idle_timeout(),
+        )
     }
 
     fn inject_connection_established(
diff --git a/protocols/gossipsub/src/handler.rs b/protocols/gossipsub/src/handler.rs
index 040586d98f5..77fa35f0a96 100644
--- a/protocols/gossipsub/src/handler.rs
+++ b/protocols/gossipsub/src/handler.rs
@@ -18,7 +18,6 @@
 // FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 // DEALINGS IN THE SOFTWARE.
 
-use crate::config::ValidationMode;
 use crate::error::{GossipsubHandlerError, ValidationError};
 use crate::protocol::{GossipsubCodec, ProtocolConfig};
 use crate::types::{GossipsubRpc, PeerKind, RawGossipsubMessage};
@@ -164,52 +163,12 @@ enum OutboundSubstreamState {
 impl GossipsubHandler {
     /// Builds a new [`GossipsubHandler`].
     pub fn new(
-        protocol_id_prefix: std::borrow::Cow<'static, str>,
-        max_transmit_size: usize,
-        validation_mode: ValidationMode,
+        protocol_config: ProtocolConfig,
         idle_timeout: Duration,
-        support_floodsub: bool,
     ) -> Self {
         GossipsubHandler {
             listen_protocol: SubstreamProtocol::new(
-                ProtocolConfig::new(
-                    protocol_id_prefix,
-                    max_transmit_size,
-                    validation_mode,
-                    support_floodsub,
-                ),
-                (),
-            ),
-            inbound_substream: None,
-            outbound_substream: None,
-            outbound_substream_establishing: false,
-            outbound_substreams_created: 0,
-            inbound_substreams_created: 0,
-            send_queue: SmallVec::new(),
-            peer_kind: None,
-            peer_kind_sent: false,
-            protocol_unsupported: false,
-            idle_timeout,
-            upgrade_errors: VecDeque::new(),
-            keep_alive: KeepAlive::Until(Instant::now() + Duration::from_secs(INITIAL_KEEP_ALIVE)),
-            in_mesh: false,
-        }
-    }
-
-    /// Builds a new [`GossipsubHandler`] with a custom Protocol ID
-    pub fn new_custom(
-        protocol_id: std::borrow::Cow<'static, str>,
-        max_transmit_size: usize,
-        validation_mode: ValidationMode,
-        idle_timeout: Duration,
-    ) -> Self {
-        GossipsubHandler {
-            listen_protocol: SubstreamProtocol::new(
-                ProtocolConfig::new_custom(
-                    protocol_id,
-                    max_transmit_size,
-                    validation_mode,
-                ),
+                protocol_config,
                 (),
             ),
             inbound_substream: None,
diff --git a/protocols/gossipsub/src/protocol.rs b/protocols/gossipsub/src/protocol.rs
index 659e2ade6b3..c25b348791b 100644
--- a/protocols/gossipsub/src/protocol.rs
+++ b/protocols/gossipsub/src/protocol.rs
@@ -59,37 +59,28 @@ impl ProtocolConfig {
     ///
     /// Sets the maximum gossip transmission size.
     pub fn new(
-        id_prefix: Cow<'static, str>,
+        id: Cow<'static, str>,
         max_transmit_size: usize,
         validation_mode: ValidationMode,
         support_floodsub: bool,
+        support_custom: bool,
     ) -> ProtocolConfig {
-        // support version 1.1.0 and 1.0.0 with user-customized prefix
-        let mut protocol_ids = vec![
-            ProtocolId::new(id_prefix.clone(), PeerKind::Gossipsubv1_1),
-            ProtocolId::new(id_prefix, PeerKind::Gossipsub),
-        ];
-
-        // add floodsub support if enabled.
-        if support_floodsub {
-            protocol_ids.push(ProtocolId::new(Cow::from(""), PeerKind::Floodsub));
-        }
-
-        ProtocolConfig {
-            protocol_ids,
-            max_transmit_size,
-            validation_mode,
-        }
-    }
-
-    pub fn new_custom(
-        protocol_id: Cow<'static, str>,
-        max_transmit_size: usize,
-        validation_mode: ValidationMode
-    ) -> ProtocolConfig {
-        let protocol_ids = vec![
-            ProtocolId::new(protocol_id, PeerKind::Custom),
-        ];
+        let protocol_ids = match support_custom {
+            true => vec![ProtocolId::new(id, PeerKind::Custom)],
+            false => {
+                // support version 1.1.0 and 1.0.0 with user-customized prefix
+                let mut protocol_ids = vec![
+                    ProtocolId::new(id.clone(), PeerKind::Gossipsubv1_1),
+                    ProtocolId::new(id, PeerKind::Gossipsub),
+                ];
+
+                // add floodsub support if enabled.
+                if support_floodsub {
+                    protocol_ids.push(ProtocolId::new(Cow::from(""), PeerKind::Floodsub));
+                }
+                protocol_ids
+            }
+        };
 
         ProtocolConfig {
             protocol_ids,

From 0726aaea0b8fb4a8e9f18c19116f261ae7bfec78 Mon Sep 17 00:00:00 2001
From: "Bernardo A. Rodrigues" <bernardo@parity.io>
Date: Sun, 26 Jun 2022 18:50:58 -0300
Subject: [PATCH 3/8] drop PeerKind::Custom; rename protocol_id; introduce
 protocol_id_prefix flag

---
 protocols/gossipsub/src/behaviour.rs |  7 +--
 protocols/gossipsub/src/config.rs    | 70 ++++++++++++++++++----------
 protocols/gossipsub/src/protocol.rs  | 40 ++++++++--------
 protocols/gossipsub/src/types.rs     |  3 --
 4 files changed, 66 insertions(+), 54 deletions(-)

diff --git a/protocols/gossipsub/src/behaviour.rs b/protocols/gossipsub/src/behaviour.rs
index ae5df864491..c8c96a94d1a 100644
--- a/protocols/gossipsub/src/behaviour.rs
+++ b/protocols/gossipsub/src/behaviour.rs
@@ -3057,14 +3057,11 @@ where
 
     fn new_handler(&mut self) -> Self::ConnectionHandler {
         let protocol_config = ProtocolConfig::new(
-            match self.config.support_custom() {
-                true => self.config.custom_protocol_id().clone(),
-                false => self.config.protocol_id_prefix().clone(),
-            },
+            self.config.protocol_id().clone(),
             self.config.max_transmit_size(),
             self.config.validation_mode().clone(),
             self.config.support_floodsub(),
-            self.config.support_custom(),
+            self.config.protocol_id_is_prefix(),
         );
 
         GossipsubHandler::new(
diff --git a/protocols/gossipsub/src/config.rs b/protocols/gossipsub/src/config.rs
index ee700b252d2..3807ae7214d 100644
--- a/protocols/gossipsub/src/config.rs
+++ b/protocols/gossipsub/src/config.rs
@@ -52,8 +52,8 @@ pub enum ValidationMode {
 /// Configuration parameters that define the performance of the gossipsub network.
 #[derive(Clone)]
 pub struct GossipsubConfig {
-    protocol_id_prefix: Cow<'static, str>,
-    custom_protocol_id: Cow<'static, str>,
+    protocol_id_prefix: bool,
+    protocol_id: Cow<'static, str>,
     history_length: usize,
     history_gossip: usize,
     mesh_n: usize,
@@ -91,25 +91,22 @@ pub struct GossipsubConfig {
     max_ihave_messages: usize,
     iwant_followup_time: Duration,
     support_floodsub: bool,
-    support_custom: bool,
     published_message_ids_cache_time: Duration,
 }
 
 impl GossipsubConfig {
     // All the getters
 
-    /// The protocol id prefix to negotiate this protocol. The protocol id is of the form
-    /// `/<prefix>/<supported-versions>`. As gossipsub supports version 1.0 and 1.1, there are two
-    /// protocol id's supported.
+    /// The protocol id to negotiate this protocol. By default, the resulting protocol id has the form
+    /// `/<prefix>/<supported-versions>`, but can optionally be changed to a literal form by disabling the `protocol_id_prefix` flag.
+    /// As gossipsub supports version 1.0 and 1.1, there are two suffixes supported for the resulting protocol id.
+    ///
+    /// Calling `GossipsubConfigBuilder::protocol_id_prefix` will set a new prefix and retain the prefix logic.
+    /// Calling `GossipsubConfigBuilder::protocol_id` will set a custom `protocol_id` and disable the prefix logic.
     ///
     /// The default prefix is `meshsub`, giving the supported protocol ids: `/meshsub/1.1.0` and `/meshsub/1.0.0`, negotiated in that order.
-    pub fn protocol_id_prefix(&self) -> &Cow<'static, str> {
-        &self.protocol_id_prefix
-    }
-
-    /// The custom protocol id. It is optional and will replace anything that is set on protocol_id_prefix.
-    pub fn custom_protocol_id(&self) -> &Cow<'static, str> {
-        &self.custom_protocol_id
+    pub fn protocol_id(&self) -> &Cow<'static, str> {
+        &self.protocol_id
     }
 
     // Overlay network parameters.
@@ -377,9 +374,9 @@ impl GossipsubConfig {
         self.support_floodsub
     }
 
-    /// Enable support for custom Gossipsub Protocol IDs. Default false.
-    pub fn support_custom(&self) -> bool {
-        self.support_custom
+    /// Gossipsub Protocol ID follows a prefix logic. Default true.
+    pub fn protocol_id_is_prefix(&self) -> bool {
+        self.protocol_id_prefix
     }
 
     /// Published message ids time cache duration. The default is 10 seconds.
@@ -406,8 +403,8 @@ impl Default for GossipsubConfigBuilder {
     fn default() -> Self {
         GossipsubConfigBuilder {
             config: GossipsubConfig {
-                protocol_id_prefix: Cow::Borrowed("meshsub"),
-                custom_protocol_id: Cow::Borrowed(""),
+                protocol_id_prefix: true,
+                protocol_id: Cow::Borrowed("meshsub"),
                 history_length: 5,
                 history_gossip: 3,
                 mesh_n: 6,
@@ -457,7 +454,6 @@ impl Default for GossipsubConfigBuilder {
                 max_ihave_messages: 10,
                 iwant_followup_time: Duration::from_secs(3),
                 support_floodsub: false,
-                support_custom: false,
                 published_message_ids_cache_time: Duration::from_secs(10),
             },
         }
@@ -473,14 +469,15 @@ impl From<GossipsubConfig> for GossipsubConfigBuilder {
 impl GossipsubConfigBuilder {
     /// The protocol id prefix to negotiate this protocol (default is `/meshsub/1.0.0`).
     pub fn protocol_id_prefix(&mut self, protocol_id_prefix: impl Into<Cow<'static, str>>) -> &mut Self {
-        self.config.protocol_id_prefix = protocol_id_prefix.into();
+        self.config.protocol_id_prefix = true;
+        self.config.protocol_id = protocol_id_prefix.into();
         self
     }
 
-    /// The custom protocol id to negotiate this protocol (overrides any prefix set via `protocol_id_prefix`)
+    /// The full protocol id to negotiate this protocol (does not append `/1.0.0` or `/1.1.0`).
     pub fn protocol_id(&mut self, protocol_id: impl Into<Cow<'static, str>>) -> &mut Self {
-        self.config.support_custom = true;
-        self.config.custom_protocol_id = protocol_id.into();
+        self.config.protocol_id_prefix = false;
+        self.config.protocol_id = protocol_id.into();
         self
     }
 
@@ -832,7 +829,7 @@ impl std::fmt::Debug for GossipsubConfig {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         let mut builder = f.debug_struct("GossipsubConfig");
         let _ = builder.field("protocol_id_prefix", &self.protocol_id_prefix);
-        let _ = builder.field("custom_protocol_id", &self.custom_protocol_id);
+        let _ = builder.field("protocol_id", &self.protocol_id);
         let _ = builder.field("history_length", &self.history_length);
         let _ = builder.field("history_gossip", &self.history_gossip);
         let _ = builder.field("mesh_n", &self.mesh_n);
@@ -864,7 +861,6 @@ impl std::fmt::Debug for GossipsubConfig {
         let _ = builder.field("max_ihave_messages", &self.max_ihave_messages);
         let _ = builder.field("iwant_followup_time", &self.iwant_followup_time);
         let _ = builder.field("support_floodsub", &self.support_floodsub);
-        let _ = builder.field("support_custom", &self.support_custom);
         let _ = builder.field(
             "published_message_ids_cache_time",
             &self.published_message_ids_cache_time,
@@ -966,4 +962,28 @@ mod test {
         let result = builder.message_id(&get_gossipsub_message());
         assert_eq!(result, get_expected_message_id());
     }
+
+    #[test]
+    fn create_config_with_protocol_id_prefix() {
+        let builder: GossipsubConfig = GossipsubConfigBuilder::default()
+            .protocol_id_prefix("purple")
+            .message_id_fn(message_id_plain_function)
+            .build()
+            .unwrap();
+
+        assert_eq!(builder.protocol_id(), "purple");
+        assert_eq!(builder.protocol_id_prefix, true);
+    }
+
+    #[test]
+    fn create_config_with_custom_protocol_id() {
+        let builder: GossipsubConfig = GossipsubConfigBuilder::default()
+            .protocol_id("purple")
+            .message_id_fn(message_id_plain_function)
+            .build()
+            .unwrap();
+
+        assert_eq!(builder.protocol_id(), "purple");
+        assert_eq!(builder.protocol_id_prefix, false);
+    }
 }
diff --git a/protocols/gossipsub/src/protocol.rs b/protocols/gossipsub/src/protocol.rs
index c25b348791b..4e4b4b72b34 100644
--- a/protocols/gossipsub/src/protocol.rs
+++ b/protocols/gossipsub/src/protocol.rs
@@ -63,24 +63,17 @@ impl ProtocolConfig {
         max_transmit_size: usize,
         validation_mode: ValidationMode,
         support_floodsub: bool,
-        support_custom: bool,
+        id_is_prefix: bool,
     ) -> ProtocolConfig {
-        let protocol_ids = match support_custom {
-            true => vec![ProtocolId::new(id, PeerKind::Custom)],
-            false => {
-                // support version 1.1.0 and 1.0.0 with user-customized prefix
-                let mut protocol_ids = vec![
-                    ProtocolId::new(id.clone(), PeerKind::Gossipsubv1_1),
-                    ProtocolId::new(id, PeerKind::Gossipsub),
-                ];
-
-                // add floodsub support if enabled.
-                if support_floodsub {
-                    protocol_ids.push(ProtocolId::new(Cow::from(""), PeerKind::Floodsub));
-                }
-                protocol_ids
-            }
-        };
+        let mut protocol_ids = vec![
+            ProtocolId::new(id.clone(), PeerKind::Gossipsubv1_1, id_is_prefix),
+            ProtocolId::new(id, PeerKind::Gossipsub, id_is_prefix),
+        ];
+
+        // add floodsub support if enabled.
+        if support_floodsub {
+            protocol_ids.push(ProtocolId::new(Cow::from(""), PeerKind::Floodsub, false));
+        }
 
         ProtocolConfig {
             protocol_ids,
@@ -101,12 +94,17 @@ pub struct ProtocolId {
 
 /// An RPC protocol ID.
 impl ProtocolId {
-    pub fn new(prefix_or_custom: Cow<'static, str>, kind: PeerKind) -> Self {
+    pub fn new(id: Cow<'static, str>, kind: PeerKind, prefix: bool) -> Self {
         let protocol_id = match kind {
-            PeerKind::Gossipsubv1_1 => format!("/{}/{}", prefix_or_custom, "1.1.0"),
-            PeerKind::Gossipsub => format!("/{}/{}", prefix_or_custom, "1.0.0"),
+            PeerKind::Gossipsubv1_1 => match prefix {
+                true => format!("/{}/{}", id, "1.1.0"),
+                false => format!("{}", id),
+            },
+            PeerKind::Gossipsub => match prefix {
+                true => format!("/{}/{}", id, "1.0.0"),
+                false => format!("{}", id),
+            },
             PeerKind::Floodsub => format!("/{}/{}", "floodsub", "1.0.0"),
-            PeerKind::Custom => format!("{}", prefix_or_custom),
             // NOTE: This is used for informing the behaviour of unsupported peers. We do not
             // advertise this variant.
             PeerKind::NotSupported => unreachable!("Should never advertise NotSupported"),
diff --git a/protocols/gossipsub/src/types.rs b/protocols/gossipsub/src/types.rs
index 41506b257a4..6ffde514e37 100644
--- a/protocols/gossipsub/src/types.rs
+++ b/protocols/gossipsub/src/types.rs
@@ -103,8 +103,6 @@ pub enum PeerKind {
     Gossipsub,
     /// A floodsub peer.
     Floodsub,
-    /// A custom gossipsub peer.
-    Custom,
     /// The peer doesn't support any of the protocols.
     NotSupported,
 }
@@ -374,7 +372,6 @@ impl PeerKind {
     pub fn as_static_ref(&self) -> &'static str {
         match self {
             Self::NotSupported => "Not Supported",
-            Self::Custom => "Custom",
             Self::Floodsub => "Floodsub",
             Self::Gossipsub => "Gossipsub v1.0",
             Self::Gossipsubv1_1 => "Gossipsub v1.1",

From 97749f070eef1700041235082d083f75c85e9e2a Mon Sep 17 00:00:00 2001
From: "Bernardo A. Rodrigues" <bernardo@parity.io>
Date: Wed, 29 Jun 2022 13:25:20 -0300
Subject: [PATCH 4/8] introduce GossipsubVersion enum

---
 protocols/gossipsub/src/behaviour.rs |  2 +-
 protocols/gossipsub/src/config.rs    | 36 ++++++++++++++++------------
 protocols/gossipsub/src/lib.rs       |  2 +-
 protocols/gossipsub/src/protocol.rs  | 32 ++++++++++++++++---------
 4 files changed, 44 insertions(+), 28 deletions(-)

diff --git a/protocols/gossipsub/src/behaviour.rs b/protocols/gossipsub/src/behaviour.rs
index c8c96a94d1a..7994248c1bc 100644
--- a/protocols/gossipsub/src/behaviour.rs
+++ b/protocols/gossipsub/src/behaviour.rs
@@ -3058,10 +3058,10 @@ where
     fn new_handler(&mut self) -> Self::ConnectionHandler {
         let protocol_config = ProtocolConfig::new(
             self.config.protocol_id().clone(),
+            self.config.custom_id_version().clone(),
             self.config.max_transmit_size(),
             self.config.validation_mode().clone(),
             self.config.support_floodsub(),
-            self.config.protocol_id_is_prefix(),
         );
 
         GossipsubHandler::new(
diff --git a/protocols/gossipsub/src/config.rs b/protocols/gossipsub/src/config.rs
index 3807ae7214d..1d0a41ef278 100644
--- a/protocols/gossipsub/src/config.rs
+++ b/protocols/gossipsub/src/config.rs
@@ -49,11 +49,18 @@ pub enum ValidationMode {
     None,
 }
 
+/// Selector for custom Protocol Id
+#[derive(Clone, Debug, PartialEq)]
+pub enum GossipsubVersion {
+    V1_0,
+    V1_1,
+}
+
 /// Configuration parameters that define the performance of the gossipsub network.
 #[derive(Clone)]
 pub struct GossipsubConfig {
-    protocol_id_prefix: bool,
     protocol_id: Cow<'static, str>,
+    custom_id_version: Option<GossipsubVersion>,
     history_length: usize,
     history_gossip: usize,
     mesh_n: usize,
@@ -98,7 +105,7 @@ impl GossipsubConfig {
     // All the getters
 
     /// The protocol id to negotiate this protocol. By default, the resulting protocol id has the form
-    /// `/<prefix>/<supported-versions>`, but can optionally be changed to a literal form by disabling the `protocol_id_prefix` flag.
+    /// `/<prefix>/<supported-versions>`, but can optionally be changed to a literal form by providing some GossipsubVersion as custom_id_version.
     /// As gossipsub supports version 1.0 and 1.1, there are two suffixes supported for the resulting protocol id.
     ///
     /// Calling `GossipsubConfigBuilder::protocol_id_prefix` will set a new prefix and retain the prefix logic.
@@ -109,6 +116,10 @@ impl GossipsubConfig {
         &self.protocol_id
     }
 
+    pub fn custom_id_version(&self) -> &Option<GossipsubVersion> {
+        &self.custom_id_version
+    }
+
     // Overlay network parameters.
     /// Number of heartbeats to keep in the `memcache` (default is 5).
     pub fn history_length(&self) -> usize {
@@ -374,11 +385,6 @@ impl GossipsubConfig {
         self.support_floodsub
     }
 
-    /// Gossipsub Protocol ID follows a prefix logic. Default true.
-    pub fn protocol_id_is_prefix(&self) -> bool {
-        self.protocol_id_prefix
-    }
-
     /// Published message ids time cache duration. The default is 10 seconds.
     pub fn published_message_ids_cache_time(&self) -> Duration {
         self.published_message_ids_cache_time
@@ -403,8 +409,8 @@ impl Default for GossipsubConfigBuilder {
     fn default() -> Self {
         GossipsubConfigBuilder {
             config: GossipsubConfig {
-                protocol_id_prefix: true,
                 protocol_id: Cow::Borrowed("meshsub"),
+                custom_id_version: None,
                 history_length: 5,
                 history_gossip: 3,
                 mesh_n: 6,
@@ -469,14 +475,14 @@ impl From<GossipsubConfig> for GossipsubConfigBuilder {
 impl GossipsubConfigBuilder {
     /// The protocol id prefix to negotiate this protocol (default is `/meshsub/1.0.0`).
     pub fn protocol_id_prefix(&mut self, protocol_id_prefix: impl Into<Cow<'static, str>>) -> &mut Self {
-        self.config.protocol_id_prefix = true;
+        self.config.custom_id_version = None;
         self.config.protocol_id = protocol_id_prefix.into();
         self
     }
 
     /// The full protocol id to negotiate this protocol (does not append `/1.0.0` or `/1.1.0`).
-    pub fn protocol_id(&mut self, protocol_id: impl Into<Cow<'static, str>>) -> &mut Self {
-        self.config.protocol_id_prefix = false;
+    pub fn protocol_id(&mut self, protocol_id: impl Into<Cow<'static, str>>, custom_id_version: GossipsubVersion) -> &mut Self {
+        self.config.custom_id_version = Some(custom_id_version);
         self.config.protocol_id = protocol_id.into();
         self
     }
@@ -828,8 +834,8 @@ impl GossipsubConfigBuilder {
 impl std::fmt::Debug for GossipsubConfig {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         let mut builder = f.debug_struct("GossipsubConfig");
-        let _ = builder.field("protocol_id_prefix", &self.protocol_id_prefix);
         let _ = builder.field("protocol_id", &self.protocol_id);
+        let _ = builder.field("custom_id_version", &self.custom_id_version);
         let _ = builder.field("history_length", &self.history_length);
         let _ = builder.field("history_gossip", &self.history_gossip);
         let _ = builder.field("mesh_n", &self.mesh_n);
@@ -972,18 +978,18 @@ mod test {
             .unwrap();
 
         assert_eq!(builder.protocol_id(), "purple");
-        assert_eq!(builder.protocol_id_prefix, true);
+        assert_eq!(builder.custom_id_version(), &None);
     }
 
     #[test]
     fn create_config_with_custom_protocol_id() {
         let builder: GossipsubConfig = GossipsubConfigBuilder::default()
-            .protocol_id("purple")
+            .protocol_id("purple", GossipsubVersion::V1_0)
             .message_id_fn(message_id_plain_function)
             .build()
             .unwrap();
 
         assert_eq!(builder.protocol_id(), "purple");
-        assert_eq!(builder.protocol_id_prefix, false);
+        assert_eq!(builder.custom_id_version(), &Some(GossipsubVersion::V1_0));
     }
 }
diff --git a/protocols/gossipsub/src/lib.rs b/protocols/gossipsub/src/lib.rs
index 0168a0a2842..d86263aace4 100644
--- a/protocols/gossipsub/src/lib.rs
+++ b/protocols/gossipsub/src/lib.rs
@@ -160,7 +160,7 @@ mod rpc_proto;
 pub use self::behaviour::{Gossipsub, GossipsubEvent, MessageAuthenticity};
 pub use self::transform::{DataTransform, IdentityTransform};
 
-pub use self::config::{GossipsubConfig, GossipsubConfigBuilder, ValidationMode};
+pub use self::config::{GossipsubConfig, GossipsubConfigBuilder, GossipsubVersion, ValidationMode};
 pub use self::peer_score::{
     score_parameter_decay, score_parameter_decay_with_base, PeerScoreParams, PeerScoreThresholds,
     TopicScoreParams,
diff --git a/protocols/gossipsub/src/protocol.rs b/protocols/gossipsub/src/protocol.rs
index 4e4b4b72b34..c0ebe72a031 100644
--- a/protocols/gossipsub/src/protocol.rs
+++ b/protocols/gossipsub/src/protocol.rs
@@ -18,7 +18,7 @@
 // FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 // DEALINGS IN THE SOFTWARE.
 
-use crate::config::ValidationMode;
+use crate::config::{GossipsubVersion, ValidationMode};
 use crate::error::{GossipsubHandlerError, ValidationError};
 use crate::handler::HandlerEvent;
 use crate::rpc_proto;
@@ -60,20 +60,30 @@ impl ProtocolConfig {
     /// Sets the maximum gossip transmission size.
     pub fn new(
         id: Cow<'static, str>,
+        custom_id_peer_kind: Option<GossipsubVersion>,
         max_transmit_size: usize,
         validation_mode: ValidationMode,
         support_floodsub: bool,
-        id_is_prefix: bool,
     ) -> ProtocolConfig {
-        let mut protocol_ids = vec![
-            ProtocolId::new(id.clone(), PeerKind::Gossipsubv1_1, id_is_prefix),
-            ProtocolId::new(id, PeerKind::Gossipsub, id_is_prefix),
-        ];
-
-        // add floodsub support if enabled.
-        if support_floodsub {
-            protocol_ids.push(ProtocolId::new(Cow::from(""), PeerKind::Floodsub, false));
-        }
+        let protocol_ids = match custom_id_peer_kind {
+            Some(v) => match v {
+                GossipsubVersion::V1_0 => vec![ProtocolId::new(id, PeerKind::Gossipsub, false)],
+                GossipsubVersion::V1_1 => vec![ProtocolId::new(id, PeerKind::Gossipsubv1_1, false)]
+            }
+            None => {
+                let mut protocol_ids = vec![
+                    ProtocolId::new(id.clone(), PeerKind::Gossipsubv1_1, true),
+                    ProtocolId::new(id, PeerKind::Gossipsub, true),
+                ];
+
+                // add floodsub support if enabled.
+                if support_floodsub {
+                    protocol_ids.push(ProtocolId::new(Cow::from(""), PeerKind::Floodsub, false));
+                }
+
+                protocol_ids
+            }
+        };
 
         ProtocolConfig {
             protocol_ids,

From c7ef6fa182c7f3a92f9b87d44cb9662302b4083c Mon Sep 17 00:00:00 2001
From: "Bernardo A. Rodrigues" <bernardo@parity.io>
Date: Thu, 30 Jun 2022 11:59:40 -0300
Subject: [PATCH 5/8] test serialised protocol ids

---
 protocols/gossipsub/src/config.rs | 34 +++++++++++++++++++++++++++++++
 1 file changed, 34 insertions(+)

diff --git a/protocols/gossipsub/src/config.rs b/protocols/gossipsub/src/config.rs
index 1d0a41ef278..a97782d77ca 100644
--- a/protocols/gossipsub/src/config.rs
+++ b/protocols/gossipsub/src/config.rs
@@ -878,10 +878,14 @@ impl std::fmt::Debug for GossipsubConfig {
 #[cfg(test)]
 mod test {
     use super::*;
+    use crate::{Gossipsub, MessageAuthenticity};
     use crate::topic::IdentityHash;
     use crate::Topic;
     use std::collections::hash_map::DefaultHasher;
     use std::hash::{Hash, Hasher};
+    use libp2p_core::UpgradeInfo;
+    use libp2p_swarm::{ConnectionHandler, NetworkBehaviour};
+    use crate::types::PeerKind;
 
     #[test]
     fn create_thing() {
@@ -973,23 +977,53 @@ mod test {
     fn create_config_with_protocol_id_prefix() {
         let builder: GossipsubConfig = GossipsubConfigBuilder::default()
             .protocol_id_prefix("purple")
+            .validation_mode(ValidationMode::Anonymous)
             .message_id_fn(message_id_plain_function)
             .build()
             .unwrap();
 
         assert_eq!(builder.protocol_id(), "purple");
         assert_eq!(builder.custom_id_version(), &None);
+
+        let mut gossipsub: Gossipsub = Gossipsub::new(MessageAuthenticity::Anonymous, builder)
+            .expect("Correct configuration");
+
+        let handler = gossipsub.new_handler();
+        let (protocol_config, _) = handler.listen_protocol().into_upgrade();
+        let protocol_ids = protocol_config.protocol_info();
+
+        assert_eq!(protocol_ids.len(), 2);
+
+        assert_eq!(protocol_ids[0].protocol_id, b"/purple/1.1.0".to_vec());
+        assert_eq!(protocol_ids[0].kind, PeerKind::Gossipsubv1_1);
+
+        assert_eq!(protocol_ids[1].protocol_id, b"/purple/1.0.0".to_vec());
+        assert_eq!(protocol_ids[1].kind, PeerKind::Gossipsub);
+
     }
 
     #[test]
     fn create_config_with_custom_protocol_id() {
         let builder: GossipsubConfig = GossipsubConfigBuilder::default()
             .protocol_id("purple", GossipsubVersion::V1_0)
+            .validation_mode(ValidationMode::Anonymous)
             .message_id_fn(message_id_plain_function)
             .build()
             .unwrap();
 
         assert_eq!(builder.protocol_id(), "purple");
         assert_eq!(builder.custom_id_version(), &Some(GossipsubVersion::V1_0));
+
+        let mut gossipsub: Gossipsub = Gossipsub::new(MessageAuthenticity::Anonymous, builder)
+            .expect("Correct configuration");
+
+        let handler = gossipsub.new_handler();
+        let (protocol_config, _) = handler.listen_protocol().into_upgrade();
+        let protocol_ids = protocol_config.protocol_info();
+
+        assert_eq!(protocol_ids.len(), 1);
+
+        assert_eq!(protocol_ids[0].protocol_id, b"purple".to_vec());
+        assert_eq!(protocol_ids[0].kind, PeerKind::Gossipsub);
     }
 }

From 3348f9384d357d8ec530053f848f44513371d497 Mon Sep 17 00:00:00 2001
From: "Bernardo A. Rodrigues" <bernardo@parity.io>
Date: Fri, 1 Jul 2022 15:44:11 -0300
Subject: [PATCH 6/8] note new protocol_id function to changelog

---
 protocols/gossipsub/CHANGELOG.md | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/protocols/gossipsub/CHANGELOG.md b/protocols/gossipsub/CHANGELOG.md
index 09dec97c435..c07e4163370 100644
--- a/protocols/gossipsub/CHANGELOG.md
+++ b/protocols/gossipsub/CHANGELOG.md
@@ -4,6 +4,8 @@
 
 - Update to `libp2p-swarm` `v0.37.0`.
 
+- Allow for custom protocol ID via `GossipsubConfigBuilder::protocol_id()`. See [PR 2718].
+
 # 0.38.1
 
 - Fix duplicate connection id. See [PR 2702].

From c9eee350484d7a01675b3b88dd4b780e1ca60a78 Mon Sep 17 00:00:00 2001
From: Max Inden <mail@max-inden.de>
Date: Sat, 2 Jul 2022 03:10:13 +0200
Subject: [PATCH 7/8] Update protocols/gossipsub/CHANGELOG.md

---
 protocols/gossipsub/CHANGELOG.md | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/protocols/gossipsub/CHANGELOG.md b/protocols/gossipsub/CHANGELOG.md
index c07e4163370..f8c6d9e4ada 100644
--- a/protocols/gossipsub/CHANGELOG.md
+++ b/protocols/gossipsub/CHANGELOG.md
@@ -6,6 +6,8 @@
 
 - Allow for custom protocol ID via `GossipsubConfigBuilder::protocol_id()`. See [PR 2718].
 
+[PR 2718]: https://github.com/libp2p/rust-libp2p/pull/2718/
+
 # 0.38.1
 
 - Fix duplicate connection id. See [PR 2702].

From 6b3450d446ebb3fdd13a67c97afdc5d8ef534c99 Mon Sep 17 00:00:00 2001
From: "Bernardo A. Rodrigues" <bernardo@parity.io>
Date: Fri, 1 Jul 2022 22:33:26 -0300
Subject: [PATCH 8/8] rustfmt

---
 protocols/gossipsub/src/behaviour.rs |  7 ++-----
 protocols/gossipsub/src/config.rs    | 28 +++++++++++++++++-----------
 protocols/gossipsub/src/handler.rs   | 10 ++--------
 protocols/gossipsub/src/protocol.rs  |  4 ++--
 4 files changed, 23 insertions(+), 26 deletions(-)

diff --git a/protocols/gossipsub/src/behaviour.rs b/protocols/gossipsub/src/behaviour.rs
index fe7a86e4cb7..3ec0b117d58 100644
--- a/protocols/gossipsub/src/behaviour.rs
+++ b/protocols/gossipsub/src/behaviour.rs
@@ -54,7 +54,7 @@ use crate::handler::{GossipsubHandler, GossipsubHandlerIn, HandlerEvent};
 use crate::mcache::MessageCache;
 use crate::metrics::{Churn, Config as MetricsConfig, Inclusion, Metrics, Penalty};
 use crate::peer_score::{PeerScore, PeerScoreParams, PeerScoreThresholds, RejectReason};
-use crate::protocol::{SIGNING_PREFIX, ProtocolConfig};
+use crate::protocol::{ProtocolConfig, SIGNING_PREFIX};
 use crate::subscription_filter::{AllowAllSubscriptionFilter, TopicSubscriptionFilter};
 use crate::time_cache::{DuplicateCache, TimeCache};
 use crate::topic::{Hasher, Topic, TopicHash};
@@ -3061,10 +3061,7 @@ where
             self.config.support_floodsub(),
         );
 
-        GossipsubHandler::new(
-            protocol_config,
-            self.config.idle_timeout(),
-        )
+        GossipsubHandler::new(protocol_config, self.config.idle_timeout())
     }
 
     fn inject_connection_established(
diff --git a/protocols/gossipsub/src/config.rs b/protocols/gossipsub/src/config.rs
index a97782d77ca..93939757c63 100644
--- a/protocols/gossipsub/src/config.rs
+++ b/protocols/gossipsub/src/config.rs
@@ -474,14 +474,21 @@ impl From<GossipsubConfig> for GossipsubConfigBuilder {
 
 impl GossipsubConfigBuilder {
     /// The protocol id prefix to negotiate this protocol (default is `/meshsub/1.0.0`).
-    pub fn protocol_id_prefix(&mut self, protocol_id_prefix: impl Into<Cow<'static, str>>) -> &mut Self {
+    pub fn protocol_id_prefix(
+        &mut self,
+        protocol_id_prefix: impl Into<Cow<'static, str>>,
+    ) -> &mut Self {
         self.config.custom_id_version = None;
         self.config.protocol_id = protocol_id_prefix.into();
         self
     }
 
     /// The full protocol id to negotiate this protocol (does not append `/1.0.0` or `/1.1.0`).
-    pub fn protocol_id(&mut self, protocol_id: impl Into<Cow<'static, str>>, custom_id_version: GossipsubVersion) -> &mut Self {
+    pub fn protocol_id(
+        &mut self,
+        protocol_id: impl Into<Cow<'static, str>>,
+        custom_id_version: GossipsubVersion,
+    ) -> &mut Self {
         self.config.custom_id_version = Some(custom_id_version);
         self.config.protocol_id = protocol_id.into();
         self
@@ -878,14 +885,14 @@ impl std::fmt::Debug for GossipsubConfig {
 #[cfg(test)]
 mod test {
     use super::*;
-    use crate::{Gossipsub, MessageAuthenticity};
     use crate::topic::IdentityHash;
+    use crate::types::PeerKind;
     use crate::Topic;
-    use std::collections::hash_map::DefaultHasher;
-    use std::hash::{Hash, Hasher};
+    use crate::{Gossipsub, MessageAuthenticity};
     use libp2p_core::UpgradeInfo;
     use libp2p_swarm::{ConnectionHandler, NetworkBehaviour};
-    use crate::types::PeerKind;
+    use std::collections::hash_map::DefaultHasher;
+    use std::hash::{Hash, Hasher};
 
     #[test]
     fn create_thing() {
@@ -985,8 +992,8 @@ mod test {
         assert_eq!(builder.protocol_id(), "purple");
         assert_eq!(builder.custom_id_version(), &None);
 
-        let mut gossipsub: Gossipsub = Gossipsub::new(MessageAuthenticity::Anonymous, builder)
-            .expect("Correct configuration");
+        let mut gossipsub: Gossipsub =
+            Gossipsub::new(MessageAuthenticity::Anonymous, builder).expect("Correct configuration");
 
         let handler = gossipsub.new_handler();
         let (protocol_config, _) = handler.listen_protocol().into_upgrade();
@@ -999,7 +1006,6 @@ mod test {
 
         assert_eq!(protocol_ids[1].protocol_id, b"/purple/1.0.0".to_vec());
         assert_eq!(protocol_ids[1].kind, PeerKind::Gossipsub);
-
     }
 
     #[test]
@@ -1014,8 +1020,8 @@ mod test {
         assert_eq!(builder.protocol_id(), "purple");
         assert_eq!(builder.custom_id_version(), &Some(GossipsubVersion::V1_0));
 
-        let mut gossipsub: Gossipsub = Gossipsub::new(MessageAuthenticity::Anonymous, builder)
-            .expect("Correct configuration");
+        let mut gossipsub: Gossipsub =
+            Gossipsub::new(MessageAuthenticity::Anonymous, builder).expect("Correct configuration");
 
         let handler = gossipsub.new_handler();
         let (protocol_config, _) = handler.listen_protocol().into_upgrade();
diff --git a/protocols/gossipsub/src/handler.rs b/protocols/gossipsub/src/handler.rs
index 77fa35f0a96..9ea2e6ea49f 100644
--- a/protocols/gossipsub/src/handler.rs
+++ b/protocols/gossipsub/src/handler.rs
@@ -162,15 +162,9 @@ enum OutboundSubstreamState {
 
 impl GossipsubHandler {
     /// Builds a new [`GossipsubHandler`].
-    pub fn new(
-        protocol_config: ProtocolConfig,
-        idle_timeout: Duration,
-    ) -> Self {
+    pub fn new(protocol_config: ProtocolConfig, idle_timeout: Duration) -> Self {
         GossipsubHandler {
-            listen_protocol: SubstreamProtocol::new(
-                protocol_config,
-                (),
-            ),
+            listen_protocol: SubstreamProtocol::new(protocol_config, ()),
             inbound_substream: None,
             outbound_substream: None,
             outbound_substream_establishing: false,
diff --git a/protocols/gossipsub/src/protocol.rs b/protocols/gossipsub/src/protocol.rs
index c0ebe72a031..ce337c96455 100644
--- a/protocols/gossipsub/src/protocol.rs
+++ b/protocols/gossipsub/src/protocol.rs
@@ -68,8 +68,8 @@ impl ProtocolConfig {
         let protocol_ids = match custom_id_peer_kind {
             Some(v) => match v {
                 GossipsubVersion::V1_0 => vec![ProtocolId::new(id, PeerKind::Gossipsub, false)],
-                GossipsubVersion::V1_1 => vec![ProtocolId::new(id, PeerKind::Gossipsubv1_1, false)]
-            }
+                GossipsubVersion::V1_1 => vec![ProtocolId::new(id, PeerKind::Gossipsubv1_1, false)],
+            },
             None => {
                 let mut protocol_ids = vec![
                     ProtocolId::new(id.clone(), PeerKind::Gossipsubv1_1, true),