Apply cargo fmt

1 files changed, 496 insertions, 444 deletions

diff --git a/src/rpc/layout.rs b/src/rpc/layout.rs
index afd7df17..ac31da72 100644
--- a/src/rpc/layout.rs
+++ b/src/rpc/layout.rs
@@ -1,12 +1,12 @@
+use std::cmp::min;
 use std::cmp::Ordering;
-use std::cmp::{min};
-use std::collections::{HashMap};
+use std::collections::HashMap;
 
 use serde::{Deserialize, Serialize};
 
+use garage_util::bipartite::*;
 use garage_util::crdt::{AutoCrdt, Crdt, LwwMap};
 use garage_util::data::*;
-use garage_util::bipartite::*;
 
 use rand::prelude::SliceRandom;
 
@@ -168,454 +168,506 @@ impl ClusterLayout {
 		true
 	}
 
+	/// This function calculates a new partition-to-node assignation.
+	/// The computed assignation maximizes the capacity of a
+	/// partition (assuming all partitions have the same size).
+	/// Among such optimal assignation, it minimizes the distance to
+	/// the former assignation (if any) to minimize the amount of
+	/// data to be moved. A heuristic ensures node triplets
+	/// dispersion (in garage_util::bipartite::optimize_matching()).
+	pub fn calculate_partition_assignation(&mut self) -> bool {
+		//The nodes might have been updated, some might have been deleted.
+		//So we need to first update the list of nodes and retrieve the
+		//assignation.
+		let old_node_assignation = self.update_nodes_and_ring();
+
+		let (node_zone, _) = self.get_node_zone_capacity();
+
+		//We compute the optimal number of partition to assign to
+		//every node and zone.
+		if let Some((part_per_nod, part_per_zone)) = self.optimal_proportions() {
+			//We collect part_per_zone in a vec to not rely on the
+			//arbitrary order in which elements are iterated in
+			//Hashmap::iter()
+			let part_per_zone_vec = part_per_zone
+				.iter()
+				.map(|(x, y)| (x.clone(), *y))
+				.collect::<Vec<(String, usize)>>();
+			//We create an indexing of the zones
+			let mut zone_id = HashMap::<String, usize>::new();
+			for i in 0..part_per_zone_vec.len() {
+				zone_id.insert(part_per_zone_vec[i].0.clone(), i);
+			}
 
-    /// This function calculates a new partition-to-node assignation.
-    /// The computed assignation maximizes the capacity of a 
-    /// partition (assuming all partitions have the same size).
-    /// Among such optimal assignation, it minimizes the distance to
-    /// the former assignation (if any) to minimize the amount of
-    /// data to be moved. A heuristic ensures node triplets 
-    /// dispersion (in garage_util::bipartite::optimize_matching()).
-    pub fn calculate_partition_assignation(&mut self) -> bool {
-        
-        //The nodes might have been updated, some might have been deleted.
-        //So we need to first update the list of nodes and retrieve the 
-        //assignation.
-        let old_node_assignation = self.update_nodes_and_ring();
-
-        let (node_zone, _) = self.get_node_zone_capacity();
-        
-        //We compute the optimal number of partition to assign to 
-        //every node and zone.
-        if let Some((part_per_nod, part_per_zone)) = self.optimal_proportions(){
-        //We collect part_per_zone in a vec to not rely on the
-        //arbitrary order in which elements are iterated in 
-        //Hashmap::iter()
-        let part_per_zone_vec = part_per_zone.iter()
-            .map(|(x,y)| (x.clone(),*y))
-            .collect::<Vec<(String,usize)>>();
-        //We create an indexing of the zones
-        let mut zone_id = HashMap::<String,usize>::new();
-        for i in 0..part_per_zone_vec.len(){
-            zone_id.insert(part_per_zone_vec[i].0.clone(), i);
-        }
-        
-        //We compute a candidate for the new partition to zone 
-        //assignation.
-        let nb_zones = part_per_zone.len();
-        let nb_nodes = part_per_nod.len();
-        let nb_partitions = 1<<PARTITION_BITS;
-        let left_cap_vec = vec![self.replication_factor as u32 ; nb_partitions];
-        let right_cap_vec = part_per_zone_vec.iter().map(|(_,y)| *y as u32)
-            .collect();
-        let mut zone_assignation =
-                dinic_compute_matching(left_cap_vec, right_cap_vec);
-
-        
-        //We create the structure for the partition-to-node assignation.
-        let mut node_assignation = 
-         vec![vec![None; self.replication_factor ];nb_partitions];
-        //We will decrement part_per_nod to keep track of the number
-        //of partitions that we still have to associate.
-        let mut part_per_nod = part_per_nod.clone();
-        
-        //We minimize the distance to the former assignation(if any)
-        
-        //We get the id of the zones of the former assignation
-        //(and the id no_zone if there is no node assignated)
-        let no_zone = part_per_zone_vec.len();
-        let old_zone_assignation : Vec<Vec<usize>> = 
-            old_node_assignation.iter().map(|x| x.iter().map(
-                    |id| match *id { Some(i) => zone_id[&node_zone[i]] ,
-                                     None => no_zone }
-                    ).collect()).collect();
-
-        //We minimize the distance to the former zone assignation 
-        zone_assignation = optimize_matching(
-            &old_zone_assignation, &zone_assignation, nb_zones+1); //+1 for no_zone
-
-        //We need to assign partitions to nodes in their zone
-        //We first put the nodes assignation that can stay the same
-        for i in 0..nb_partitions{
-            for j in 0..self.replication_factor {
-                if let Some(Some(former_node)) = old_node_assignation[i].iter().find(
-                    |x| if let Some(id) = x {
-                        zone_id[&node_zone[*id]] == zone_assignation[i][j]
-                    }
-                    else {false}
-                    ) 
-                {
-                    if part_per_nod[*former_node] > 0 {
-                        node_assignation[i][j] = Some(*former_node);
-                        part_per_nod[*former_node] -= 1;
-                    }
-                }
-            }
-        }
-
-        
-        //We complete the assignation of partitions to nodes
-        let mut rng = rand::thread_rng();
-        for i in 0..nb_partitions {
-            for j in 0..self.replication_factor {
-                if node_assignation[i][j] == None {
-                    let possible_nodes : Vec<usize> = (0..nb_nodes)
-                        .filter(
-                        |id| zone_id[&node_zone[*id]] == zone_assignation[i][j]
-                                && part_per_nod[*id] > 0).collect();
-                    assert!(possible_nodes.len()>0);
-                    //We randomly pick a node
-                    if let Some(nod) = possible_nodes.choose(&mut rng){
-                        node_assignation[i][j] = Some(*nod);
-                        part_per_nod[*nod] -= 1;
-                    }
-                }
-            }
-        }
-
-        //We write the assignation in the 1D table
-        self.ring_assignation_data = Vec::<CompactNodeType>::new();
-        for i in 0..nb_partitions{
-            for j in 0..self.replication_factor {
-                if let Some(id) = node_assignation[i][j] {
-                    self.ring_assignation_data.push(id as CompactNodeType);
-                }
-                else {assert!(false)}
-            }
-        }
-
-        true
-        }
-        else { false }
-    }
-
-    /// The LwwMap of node roles might have changed. This function updates the node_id_vec
-    /// and returns the assignation given by ring, with the new indices of the nodes, and
-    /// None of the node is not present anymore.
-    /// We work with the assumption that only this function and calculate_new_assignation
-    /// do modify assignation_ring and node_id_vec.
-    fn update_nodes_and_ring(&mut self) -> Vec<Vec<Option<usize>>> {
-        let nb_partitions = 1usize<<PARTITION_BITS;
-        let mut node_assignation = 
-         vec![vec![None; self.replication_factor ];nb_partitions];
-        let rf = self.replication_factor;
-        let ring = &self.ring_assignation_data;
-        
-        let new_node_id_vec : Vec::<Uuid> = self.roles.items().iter()
-            .map(|(k, _, _)| *k)
-            .collect();
-        
-        if ring.len() == rf*nb_partitions {
-            for i in 0..nb_partitions {
-                for j in 0..self.replication_factor {
-                    node_assignation[i][j] = new_node_id_vec.iter()
-                        .position(|id| *id == self.node_id_vec[ring[i*rf + j] as usize]);
-                }
-            }
-        }
-
-        self.node_id_vec = new_node_id_vec;
-        self.ring_assignation_data = vec![];
-        return node_assignation;
-    }
-    
-    ///This function compute the number of partition to assign to
-    ///every node and zone, so that every partition is replicated
-    ///self.replication_factor times and the capacity of a partition
-    ///is maximized.
-    fn optimal_proportions(&mut self) -> Option<(Vec<usize>, HashMap<String, usize>)> {
-        
-        let mut zone_capacity :HashMap<String, u32>= HashMap::new();
-        
-        let (node_zone, node_capacity) = self.get_node_zone_capacity();
-        let nb_nodes = self.node_id_vec.len();
-
-        for i in 0..nb_nodes
-        {
-            if zone_capacity.contains_key(&node_zone[i]) {
-                zone_capacity.insert(node_zone[i].clone(), zone_capacity[&node_zone[i]] + node_capacity[i]);
-            }
-            else{
-                zone_capacity.insert(node_zone[i].clone(), node_capacity[i]);
-            }
-        }
-
-        //Compute the optimal number of partitions per zone
-        let sum_capacities: u32 =zone_capacity.values().sum();
-        
-        if sum_capacities <= 0 {
-            println!("No storage capacity in the network.");
-            return None;
-        }
-
-        let nb_partitions = 1<<PARTITION_BITS;
-       
-        //Initially we would like to use zones porportionally to
-        //their capacity.
-        //However, a large zone can be associated to at most
-        //nb_partitions to ensure replication of the date.
-        //So we take the min with nb_partitions:
-        let mut part_per_zone : HashMap<String, usize> = 
-            zone_capacity.iter()
-                .map(|(k, v)| (k.clone(), min(nb_partitions, 
-                    (self.replication_factor*nb_partitions
-                       **v as usize)/sum_capacities as usize) ) ).collect();
-
-        //The replication_factor-1 upper bounds the number of 
-        //part_per_zones that are greater than nb_partitions
-        for _ in 1..self.replication_factor {
-            //The number of partitions that are not assignated to
-            //a zone that takes nb_partitions.
-            let sum_capleft : u32 = zone_capacity.keys()
-                .filter(| k | {part_per_zone[*k] < nb_partitions} )
-                .map(|k| zone_capacity[k]).sum();
-            
-            //The number of replication of the data that we need
-            //to ensure.
-            let repl_left = self.replication_factor
-                - part_per_zone.values()
-                    .filter(|x| {**x == nb_partitions})
-                    .count();
-            if repl_left == 0 {
-                break;
-            }
-
-            for k in zone_capacity.keys() {
-                if part_per_zone[k] != nb_partitions 
-                {
-                    part_per_zone.insert(k.to_string() , min(nb_partitions,
-                        (nb_partitions*zone_capacity[k] as usize
-                        *repl_left)/sum_capleft as usize));
-                }
-            }
-        }
-
-        //Now we divide the zone's partition share proportionally 
-        //between their nodes.
-        
-        let mut part_per_nod : Vec<usize> = (0..nb_nodes).map(
-            |i| (part_per_zone[&node_zone[i]]*node_capacity[i] as usize)/zone_capacity[&node_zone[i]] as usize
-            )
-            .collect();
-
-        //We must update the part_per_zone to make it correspond to
-        //part_per_nod (because of integer rounding)
-        part_per_zone = part_per_zone.iter().map(|(k,_)| 
-                                              (k.clone(), 0))
-                            .collect();
-        for i in 0..nb_nodes {
-            part_per_zone.insert(
-                node_zone[i].clone() , 
-                part_per_zone[&node_zone[i]] + part_per_nod[i]);
-        }
-
-    //Because of integer rounding, the total sum of part_per_nod
-    //might not be replication_factor*nb_partitions. 
-    // We need at most to add 1 to every non maximal value of 
-    // part_per_nod. The capacity of a partition will be bounded
-    // by the minimal value of 
-    // node_capacity_vec[i]/part_per_nod[i]
-    // so we try to maximize this minimal value, keeping the 
-    // part_per_zone capped
-
-        let discrepancy : usize = 
-            nb_partitions*self.replication_factor
-            - part_per_nod.iter().sum::<usize>();
-        
-        //We use a stupid O(N^2) algorithm. If the number of nodes
-        //is actually expected to be high, one should optimize this.
-
-        for _ in 0..discrepancy {
-            if let Some(idmax) = (0..nb_nodes)
-                .filter(|i| part_per_zone[&node_zone[*i]] < nb_partitions) 
-                .max_by( |i,j|         
-                    (node_capacity[*i]*(part_per_nod[*j]+1) as u32)
-                        .cmp(&(node_capacity[*j]*(part_per_nod[*i]+1) as u32))
-                ) 
-            {
-                part_per_nod[idmax] += 1;
-                part_per_zone.insert(node_zone[idmax].clone(),part_per_zone[&node_zone[idmax]]+1);
-            }
-        }
-
-        //We check the algorithm consistency
-        
-        let discrepancy : usize = 
-            nb_partitions*self.replication_factor
-            - part_per_nod.iter().sum::<usize>();
-        assert!(discrepancy == 0);
-        assert!(if let Some(v) = part_per_zone.values().max()
-                {*v <= nb_partitions} else {false} );
-        
-        Some((part_per_nod, part_per_zone))
-    }
-    
-    
-    //Returns vectors of zone and capacity; indexed by the same (temporary)
-    //indices as node_id_vec.
-    fn get_node_zone_capacity(& self) -> (Vec<String> , Vec<u32>) {
-        
-        let node_zone = self.node_id_vec.iter().map(
-            |id_nod| match self.node_role(id_nod) {
-                Some(NodeRole{zone,capacity:_,tags:_}) => zone.clone() ,
-                _ => "".to_string()
-            }
-        ).collect();
-        
-        let node_capacity = self.node_id_vec.iter().map(
-            |id_nod| match self.node_role(id_nod) {
-                Some(NodeRole{zone:_,capacity,tags:_}) => 
-                        if let Some(c)=capacity 
-                        {*c}
-                        else {0},
-                _ => 0
-            }
-        ).collect();
-
-        (node_zone,node_capacity)
-    }
+			//We compute a candidate for the new partition to zone
+			//assignation.
+			let nb_zones = part_per_zone.len();
+			let nb_nodes = part_per_nod.len();
+			let nb_partitions = 1 << PARTITION_BITS;
+			let left_cap_vec = vec![self.replication_factor as u32; nb_partitions];
+			let right_cap_vec = part_per_zone_vec.iter().map(|(_, y)| *y as u32).collect();
+			let mut zone_assignation = dinic_compute_matching(left_cap_vec, right_cap_vec);
+
+			//We create the structure for the partition-to-node assignation.
+			let mut node_assignation = vec![vec![None; self.replication_factor]; nb_partitions];
+			//We will decrement part_per_nod to keep track of the number
+			//of partitions that we still have to associate.
+			let mut part_per_nod = part_per_nod.clone();
+
+			//We minimize the distance to the former assignation(if any)
+
+			//We get the id of the zones of the former assignation
+			//(and the id no_zone if there is no node assignated)
+			let no_zone = part_per_zone_vec.len();
+			let old_zone_assignation: Vec<Vec<usize>> = old_node_assignation
+				.iter()
+				.map(|x| {
+					x.iter()
+						.map(|id| match *id {
+							Some(i) => zone_id[&node_zone[i]],
+							None => no_zone,
+						})
+						.collect()
+				})
+				.collect();
+
+			//We minimize the distance to the former zone assignation
+			zone_assignation =
+				optimize_matching(&old_zone_assignation, &zone_assignation, nb_zones + 1); //+1 for no_zone
+
+			//We need to assign partitions to nodes in their zone
+			//We first put the nodes assignation that can stay the same
+			for i in 0..nb_partitions {
+				for j in 0..self.replication_factor {
+					if let Some(Some(former_node)) = old_node_assignation[i].iter().find(|x| {
+						if let Some(id) = x {
+							zone_id[&node_zone[*id]] == zone_assignation[i][j]
+						} else {
+							false
+						}
+					}) {
+						if part_per_nod[*former_node] > 0 {
+							node_assignation[i][j] = Some(*former_node);
+							part_per_nod[*former_node] -= 1;
+						}
+					}
+				}
+			}
 
-}
+			//We complete the assignation of partitions to nodes
+			let mut rng = rand::thread_rng();
+			for i in 0..nb_partitions {
+				for j in 0..self.replication_factor {
+					if node_assignation[i][j] == None {
+						let possible_nodes: Vec<usize> = (0..nb_nodes)
+							.filter(|id| {
+								zone_id[&node_zone[*id]] == zone_assignation[i][j]
+									&& part_per_nod[*id] > 0
+							})
+							.collect();
+						assert!(possible_nodes.len() > 0);
+						//We randomly pick a node
+						if let Some(nod) = possible_nodes.choose(&mut rng) {
+							node_assignation[i][j] = Some(*nod);
+							part_per_nod[*nod] -= 1;
+						}
+					}
+				}
+			}
+
+			//We write the assignation in the 1D table
+			self.ring_assignation_data = Vec::<CompactNodeType>::new();
+			for i in 0..nb_partitions {
+				for j in 0..self.replication_factor {
+					if let Some(id) = node_assignation[i][j] {
+						self.ring_assignation_data.push(id as CompactNodeType);
+					} else {
+						assert!(false)
+					}
+				}
+			}
 
+			true
+		} else {
+			false
+		}
+	}
+
+	/// The LwwMap of node roles might have changed. This function updates the node_id_vec
+	/// and returns the assignation given by ring, with the new indices of the nodes, and
+	/// None of the node is not present anymore.
+	/// We work with the assumption that only this function and calculate_new_assignation
+	/// do modify assignation_ring and node_id_vec.
+	fn update_nodes_and_ring(&mut self) -> Vec<Vec<Option<usize>>> {
+		let nb_partitions = 1usize << PARTITION_BITS;
+		let mut node_assignation = vec![vec![None; self.replication_factor]; nb_partitions];
+		let rf = self.replication_factor;
+		let ring = &self.ring_assignation_data;
+
+		let new_node_id_vec: Vec<Uuid> = self.roles.items().iter().map(|(k, _, _)| *k).collect();
+
+		if ring.len() == rf * nb_partitions {
+			for i in 0..nb_partitions {
+				for j in 0..self.replication_factor {
+					node_assignation[i][j] = new_node_id_vec
+						.iter()
+						.position(|id| *id == self.node_id_vec[ring[i * rf + j] as usize]);
+				}
+			}
+		}
+
+		self.node_id_vec = new_node_id_vec;
+		self.ring_assignation_data = vec![];
+		return node_assignation;
+	}
+
+	///This function compute the number of partition to assign to
+	///every node and zone, so that every partition is replicated
+	///self.replication_factor times and the capacity of a partition
+	///is maximized.
+	fn optimal_proportions(&mut self) -> Option<(Vec<usize>, HashMap<String, usize>)> {
+		let mut zone_capacity: HashMap<String, u32> = HashMap::new();
+
+		let (node_zone, node_capacity) = self.get_node_zone_capacity();
+		let nb_nodes = self.node_id_vec.len();
+
+		for i in 0..nb_nodes {
+			if zone_capacity.contains_key(&node_zone[i]) {
+				zone_capacity.insert(
+					node_zone[i].clone(),
+					zone_capacity[&node_zone[i]] + node_capacity[i],
+				);
+			} else {
+				zone_capacity.insert(node_zone[i].clone(), node_capacity[i]);
+			}
+		}
+
+		//Compute the optimal number of partitions per zone
+		let sum_capacities: u32 = zone_capacity.values().sum();
+
+		if sum_capacities <= 0 {
+			println!("No storage capacity in the network.");
+			return None;
+		}
+
+		let nb_partitions = 1 << PARTITION_BITS;
+
+		//Initially we would like to use zones porportionally to
+		//their capacity.
+		//However, a large zone can be associated to at most
+		//nb_partitions to ensure replication of the date.
+		//So we take the min with nb_partitions:
+		let mut part_per_zone: HashMap<String, usize> = zone_capacity
+			.iter()
+			.map(|(k, v)| {
+				(
+					k.clone(),
+					min(
+						nb_partitions,
+						(self.replication_factor * nb_partitions * *v as usize)
+							/ sum_capacities as usize,
+					),
+				)
+			})
+			.collect();
+
+		//The replication_factor-1 upper bounds the number of
+		//part_per_zones that are greater than nb_partitions
+		for _ in 1..self.replication_factor {
+			//The number of partitions that are not assignated to
+			//a zone that takes nb_partitions.
+			let sum_capleft: u32 = zone_capacity
+				.keys()
+				.filter(|k| part_per_zone[*k] < nb_partitions)
+				.map(|k| zone_capacity[k])
+				.sum();
+
+			//The number of replication of the data that we need
+			//to ensure.
+			let repl_left = self.replication_factor
+				- part_per_zone
+					.values()
+					.filter(|x| **x == nb_partitions)
+					.count();
+			if repl_left == 0 {
+				break;
+			}
+
+			for k in zone_capacity.keys() {
+				if part_per_zone[k] != nb_partitions {
+					part_per_zone.insert(
+						k.to_string(),
+						min(
+							nb_partitions,
+							(nb_partitions * zone_capacity[k] as usize * repl_left)
+								/ sum_capleft as usize,
+						),
+					);
+				}
+			}
+		}
+
+		//Now we divide the zone's partition share proportionally
+		//between their nodes.
+
+		let mut part_per_nod: Vec<usize> = (0..nb_nodes)
+			.map(|i| {
+				(part_per_zone[&node_zone[i]] * node_capacity[i] as usize)
+					/ zone_capacity[&node_zone[i]] as usize
+			})
+			.collect();
+
+		//We must update the part_per_zone to make it correspond to
+		//part_per_nod (because of integer rounding)
+		part_per_zone = part_per_zone.iter().map(|(k, _)| (k.clone(), 0)).collect();
+		for i in 0..nb_nodes {
+			part_per_zone.insert(
+				node_zone[i].clone(),
+				part_per_zone[&node_zone[i]] + part_per_nod[i],
+			);
+		}
+
+		//Because of integer rounding, the total sum of part_per_nod
+		//might not be replication_factor*nb_partitions.
+		// We need at most to add 1 to every non maximal value of
+		// part_per_nod. The capacity of a partition will be bounded
+		// by the minimal value of
+		// node_capacity_vec[i]/part_per_nod[i]
+		// so we try to maximize this minimal value, keeping the
+		// part_per_zone capped
+
+		let discrepancy: usize =
+			nb_partitions * self.replication_factor - part_per_nod.iter().sum::<usize>();
+
+		//We use a stupid O(N^2) algorithm. If the number of nodes
+		//is actually expected to be high, one should optimize this.
+
+		for _ in 0..discrepancy {
+			if let Some(idmax) = (0..nb_nodes)
+				.filter(|i| part_per_zone[&node_zone[*i]] < nb_partitions)
+				.max_by(|i, j| {
+					(node_capacity[*i] * (part_per_nod[*j] + 1) as u32)
+						.cmp(&(node_capacity[*j] * (part_per_nod[*i] + 1) as u32))
+				}) {
+				part_per_nod[idmax] += 1;
+				part_per_zone.insert(
+					node_zone[idmax].clone(),
+					part_per_zone[&node_zone[idmax]] + 1,
+				);
+			}
+		}
 
+		//We check the algorithm consistency
+
+		let discrepancy: usize =
+			nb_partitions * self.replication_factor - part_per_nod.iter().sum::<usize>();
+		assert!(discrepancy == 0);
+		assert!(if let Some(v) = part_per_zone.values().max() {
+			*v <= nb_partitions
+		} else {
+			false
+		});
+
+		Some((part_per_nod, part_per_zone))
+	}
+
+	//Returns vectors of zone and capacity; indexed by the same (temporary)
+	//indices as node_id_vec.
+	fn get_node_zone_capacity(&self) -> (Vec<String>, Vec<u32>) {
+		let node_zone = self
+			.node_id_vec
+			.iter()
+			.map(|id_nod| match self.node_role(id_nod) {
+				Some(NodeRole {
+					zone,
+					capacity: _,
+					tags: _,
+				}) => zone.clone(),
+				_ => "".to_string(),
+			})
+			.collect();
+
+		let node_capacity = self
+			.node_id_vec
+			.iter()
+			.map(|id_nod| match self.node_role(id_nod) {
+				Some(NodeRole {
+					zone: _,
+					capacity,
+					tags: _,
+				}) => {
+					if let Some(c) = capacity {
+						*c
+					} else {
+						0
+					}
+				}
+				_ => 0,
+			})
+			.collect();
+
+		(node_zone, node_capacity)
+	}
+}
 
 #[cfg(test)]
 mod tests {
-    use super::*;
-    use itertools::Itertools;
-
-    fn check_assignation(cl : &ClusterLayout) {
-        
-        //Check that input data has the right format
-        let nb_partitions = 1usize<<PARTITION_BITS;
-        assert!([1,2,3].contains(&cl.replication_factor));
-        assert!(cl.ring_assignation_data.len() == nb_partitions*cl.replication_factor);
-       
-        let (node_zone, node_capacity) = cl.get_node_zone_capacity();
-        
-
-        //Check that is is a correct assignation with zone redundancy
-        let rf = cl.replication_factor;
-        for i in 0..nb_partitions{
-            assert!( rf ==
-                cl.ring_assignation_data[rf*i..rf*(i+1)].iter()
-                   .map(|nod| node_zone[*nod as usize].clone())
-                   .unique()
-                   .count() );
-        }
-
-        let nb_nodes = cl.node_id_vec.len();
-        //Check optimality
-        let node_nb_part =(0..nb_nodes).map(|i| cl.ring_assignation_data
-            .iter()
-            .filter(|x| **x==i as u8)
-            .count())
-            .collect::<Vec::<_>>();
-
-        let zone_vec = node_zone.iter().unique().collect::<Vec::<_>>();
-        let zone_nb_part = zone_vec.iter().map( |z| cl.ring_assignation_data.iter()
-                                               .filter(|x| node_zone[**x as usize] == **z)
-                                               .count() 
-                                               ).collect::<Vec::<_>>();
-         
-        //Check optimality of the zone assignation : would it be better for the
-        //node_capacity/node_partitions ratio to change the assignation of a partition
-        
-        if let Some(idmin) = (0..nb_nodes).min_by(
-            |i,j| (node_capacity[*i]*node_nb_part[*j] as u32)
-                    .cmp(&(node_capacity[*j]*node_nb_part[*i] as u32))
-            ){
-        if let Some(idnew) = (0..nb_nodes)
-            .filter( |i| if let Some(p) = zone_vec.iter().position(|z| **z==node_zone[*i])
-                            {zone_nb_part[p] < nb_partitions }
-                            else { false })
-            .max_by(
-            |i,j| (node_capacity[*i]*(node_nb_part[*j]as u32+1))
-                .cmp(&(node_capacity[*j]*(node_nb_part[*i] as u32+1)))
-            ){
-                assert!(node_capacity[idmin]*(node_nb_part[idnew] as u32+1) >=
-                                node_capacity[idnew]*node_nb_part[idmin] as u32);
-            }
-
-        }
-
-        //In every zone, check optimality of the nod assignation 
-        for z in zone_vec {
-            let node_of_z_iter = (0..nb_nodes).filter(|id| node_zone[*id] == *z );
-            if let Some(idmin) = node_of_z_iter.clone().min_by(
-                |i,j| (node_capacity[*i]*node_nb_part[*j] as u32)
-                        .cmp(&(node_capacity[*j]*node_nb_part[*i] as u32))
-                ){
-            if let Some(idnew) = node_of_z_iter.min_by(
-                |i,j| (node_capacity[*i]*(node_nb_part[*j] as u32+1))
-                        .cmp(&(node_capacity[*j]*(node_nb_part[*i] as u32+1)))
-                ){
-                    assert!(node_capacity[idmin]*(node_nb_part[idnew] as u32+1) >=
-                                    node_capacity[idnew]*node_nb_part[idmin] as u32);
-            }
-            }
-        }
-        
-    }
-
-    fn update_layout(cl : &mut ClusterLayout, node_id_vec : &Vec<u8>,
-                     node_capacity_vec : &Vec<u32> , node_zone_vec : &Vec<String>) {
-        for i in 0..node_id_vec.len(){
-            if let Some(x) = FixedBytes32::try_from(&[i as u8;32]) {
-                cl.node_id_vec.push(x);
-            }
-                
-            let update = cl.roles.update_mutator(cl.node_id_vec[i] , 
-                NodeRoleV(Some(NodeRole{
-                    zone : (node_zone_vec[i].to_string()), 
-                    capacity : (Some(node_capacity_vec[i])), 
-                    tags : (vec![])})));
-            cl.roles.merge(&update);
-        }
-    }
-
-    #[test]
-    fn test_assignation() {
-
-        let mut node_id_vec =  vec![1,2,3];
-        let mut node_capacity_vec = vec![4000,1000,2000];
-        let mut node_zone_vec= vec!["A", "B", "C"].into_iter().map(|x| x.to_string()).collect();
-        
-        let mut cl =  ClusterLayout {
-            node_id_vec: vec![],
-        
-            roles : LwwMap::new(),
-
-            replication_factor: 3,
-            ring_assignation_data : vec![],
-            version:0,
-            staging: LwwMap::new(),
-            staging_hash: sha256sum(&[1;32]),
-        };
-        update_layout(&mut cl, &node_id_vec, &node_capacity_vec, &node_zone_vec);
-        cl.calculate_partition_assignation();
-        check_assignation(&cl);
-
-        node_id_vec =  vec![1,2,3, 4, 5, 6, 7, 8, 9];
-        node_capacity_vec = vec![4000,1000,1000, 3000, 1000, 1000, 2000, 10000, 2000];
-        node_zone_vec= vec!["A", "B", "C", "C", "C", "B", "G", "H", "I"].into_iter().map(|x| x.to_string()).collect();
-        update_layout(&mut cl, &node_id_vec, &node_capacity_vec, &node_zone_vec);
-        cl.calculate_partition_assignation();
-        check_assignation(&cl);
-
-        node_capacity_vec = vec![4000,1000,2000, 7000, 1000, 1000, 2000, 10000, 2000];
-        update_layout(&mut cl, &node_id_vec, &node_capacity_vec, &node_zone_vec);
-        cl.calculate_partition_assignation();
-        check_assignation(&cl);
-
-
-        node_capacity_vec = vec![4000,4000,2000, 7000, 1000, 9000, 2000, 10, 2000];
-        update_layout(&mut cl, &node_id_vec, &node_capacity_vec, &node_zone_vec);
-        cl.calculate_partition_assignation();
-        check_assignation(&cl);
-    
-    }
-}
+	use super::*;
+	use itertools::Itertools;
+
+	fn check_assignation(cl: &ClusterLayout) {
+		//Check that input data has the right format
+		let nb_partitions = 1usize << PARTITION_BITS;
+		assert!([1, 2, 3].contains(&cl.replication_factor));
+		assert!(cl.ring_assignation_data.len() == nb_partitions * cl.replication_factor);
+
+		let (node_zone, node_capacity) = cl.get_node_zone_capacity();
+
+		//Check that is is a correct assignation with zone redundancy
+		let rf = cl.replication_factor;
+		for i in 0..nb_partitions {
+			assert!(
+				rf == cl.ring_assignation_data[rf * i..rf * (i + 1)]
+					.iter()
+					.map(|nod| node_zone[*nod as usize].clone())
+					.unique()
+					.count()
+			);
+		}
+
+		let nb_nodes = cl.node_id_vec.len();
+		//Check optimality
+		let node_nb_part = (0..nb_nodes)
+			.map(|i| {
+				cl.ring_assignation_data
+					.iter()
+					.filter(|x| **x == i as u8)
+					.count()
+			})
+			.collect::<Vec<_>>();
+
+		let zone_vec = node_zone.iter().unique().collect::<Vec<_>>();
+		let zone_nb_part = zone_vec
+			.iter()
+			.map(|z| {
+				cl.ring_assignation_data
+					.iter()
+					.filter(|x| node_zone[**x as usize] == **z)
+					.count()
+			})
+			.collect::<Vec<_>>();
+
+		//Check optimality of the zone assignation : would it be better for the
+		//node_capacity/node_partitions ratio to change the assignation of a partition
+
+		if let Some(idmin) = (0..nb_nodes).min_by(|i, j| {
+			(node_capacity[*i] * node_nb_part[*j] as u32)
+				.cmp(&(node_capacity[*j] * node_nb_part[*i] as u32))
+		}) {
+			if let Some(idnew) = (0..nb_nodes)
+				.filter(|i| {
+					if let Some(p) = zone_vec.iter().position(|z| **z == node_zone[*i]) {
+						zone_nb_part[p] < nb_partitions
+					} else {
+						false
+					}
+				})
+				.max_by(|i, j| {
+					(node_capacity[*i] * (node_nb_part[*j] as u32 + 1))
+						.cmp(&(node_capacity[*j] * (node_nb_part[*i] as u32 + 1)))
+				}) {
+				assert!(
+					node_capacity[idmin] * (node_nb_part[idnew] as u32 + 1)
+						>= node_capacity[idnew] * node_nb_part[idmin] as u32
+				);
+			}
+		}
+
+		//In every zone, check optimality of the nod assignation
+		for z in zone_vec {
+			let node_of_z_iter = (0..nb_nodes).filter(|id| node_zone[*id] == *z);
+			if let Some(idmin) = node_of_z_iter.clone().min_by(|i, j| {
+				(node_capacity[*i] * node_nb_part[*j] as u32)
+					.cmp(&(node_capacity[*j] * node_nb_part[*i] as u32))
+			}) {
+				if let Some(idnew) = node_of_z_iter.min_by(|i, j| {
+					(node_capacity[*i] * (node_nb_part[*j] as u32 + 1))
+						.cmp(&(node_capacity[*j] * (node_nb_part[*i] as u32 + 1)))
+				}) {
+					assert!(
+						node_capacity[idmin] * (node_nb_part[idnew] as u32 + 1)
+							>= node_capacity[idnew] * node_nb_part[idmin] as u32
+					);
+				}
+			}
+		}
+	}
+
+	fn update_layout(
+		cl: &mut ClusterLayout,
+		node_id_vec: &Vec<u8>,
+		node_capacity_vec: &Vec<u32>,
+		node_zone_vec: &Vec<String>,
+	) {
+		for i in 0..node_id_vec.len() {
+			if let Some(x) = FixedBytes32::try_from(&[i as u8; 32]) {
+				cl.node_id_vec.push(x);
+			}
 
+			let update = cl.roles.update_mutator(
+				cl.node_id_vec[i],
+				NodeRoleV(Some(NodeRole {
+					zone: (node_zone_vec[i].to_string()),
+					capacity: (Some(node_capacity_vec[i])),
+					tags: (vec![]),
+				})),
+			);
+			cl.roles.merge(&update);
+		}
+	}
+
+	#[test]
+	fn test_assignation() {
+		let mut node_id_vec = vec![1, 2, 3];
+		let mut node_capacity_vec = vec![4000, 1000, 2000];
+		let mut node_zone_vec = vec!["A", "B", "C"]
+			.into_iter()
+			.map(|x| x.to_string())
+			.collect();
+
+		let mut cl = ClusterLayout {
+			node_id_vec: vec![],
 
+			roles: LwwMap::new(),
 
+			replication_factor: 3,
+			ring_assignation_data: vec![],
+			version: 0,
+			staging: LwwMap::new(),
+			staging_hash: sha256sum(&[1; 32]),
+		};
+		update_layout(&mut cl, &node_id_vec, &node_capacity_vec, &node_zone_vec);
+		cl.calculate_partition_assignation();
+		check_assignation(&cl);
+
+		node_id_vec = vec![1, 2, 3, 4, 5, 6, 7, 8, 9];
+		node_capacity_vec = vec![4000, 1000, 1000, 3000, 1000, 1000, 2000, 10000, 2000];
+		node_zone_vec = vec!["A", "B", "C", "C", "C", "B", "G", "H", "I"]
+			.into_iter()
+			.map(|x| x.to_string())
+			.collect();
+		update_layout(&mut cl, &node_id_vec, &node_capacity_vec, &node_zone_vec);
+		cl.calculate_partition_assignation();
+		check_assignation(&cl);
+
+		node_capacity_vec = vec![4000, 1000, 2000, 7000, 1000, 1000, 2000, 10000, 2000];
+		update_layout(&mut cl, &node_id_vec, &node_capacity_vec, &node_zone_vec);
+		cl.calculate_partition_assignation();
+		check_assignation(&cl);
+
+		node_capacity_vec = vec![4000, 4000, 2000, 7000, 1000, 9000, 2000, 10, 2000];
+		update_layout(&mut cl, &node_id_vec, &node_capacity_vec, &node_zone_vec);
+		cl.calculate_partition_assignation();
+		check_assignation(&cl);
+	}
+}