def migrate_clusters(my_address, host_pool):
"""Task that migrate every needed clusters from other server to
this new one."""
host_index = get_host_index(my_address, host_pool)
now = ClusterDistribution(nb_active_hosts(host_pool))
after = ClusterDistribution(nb_active_hosts(host_pool)+1)
needed_clusters = after.clusters_for_host(host_index)
for cluster in needed_clusters:
host_index = now.get_host_from_cluster(cluster)
host_address = host_pool[host_index]['address']
req = cluster_list_request(host_address, cluster)
data = urllib2.urlopen(req)
index_list = json.decode(data.read())
for index in index_list:
req = document_request(host_address, index)
data = urllib2.urlopen(req)
store_document(index, data.read())
#todo:notify other servers
print("Migration finished successfuly")
def test_distribution(self):
distrib = ClusterDistribution(1, nb_clusters=12)
self.assertEqual(
distrib.distribution,
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11]
)
distrib = ClusterDistribution(2, nb_clusters=12)
self.assertEqual(
distrib.distribution,
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11]
)
distrib = ClusterDistribution(3, nb_clusters=12)
self.assertEqual(
distrib.distribution,
[0, 1, 2, 3, 6, 7, 8, 9, 4, 5, 10, 11]
)
distrib = ClusterDistribution(4, nb_clusters=12)
self.assertEqual(
distrib.distribution,
[0, 1, 2, 6, 7, 8, 4, 5, 10, 3, 9, 11]
)
self.assertEqual(
distrib.clusters_for_host(0),
[0, 1, 2]
)
self.assertEqual(
distrib.clusters_for_host(3),
[3, 9, 11]
)
self.assertEqual(
distrib.get_host_from_cluster(3),
3
)
self.assertEqual(
distrib.get_host_from_cluster(11),
3
)
self.assertEqual(
distrib.get_host_from_cluster(2),
0
)