Merge branch 'master' into patch-1

1 files changed, 39 insertions, 0 deletions

diff --git a/45.md b/45.md
new file mode 100644
index 0000000..a525391
--- /dev/null
+++ b/45.md
@@ -0,0 +1,39 @@
+NIP-45
+======
+
+Event Counts
+--------------
+
+`draft` `optional` `author:staab`
+
+Relays may support the verb `COUNT`, which provides a mechanism for obtaining event counts.
+
+## Motivation
+
+Some queries a client may want to execute against connected relays are prohibitively expensive, for example, in order to retrieve follower counts for a given pubkey, a client must query all kind-3 events referring to a given pubkey only to count them. The result may be cached, either by a client or by a separate indexing server as an alternative, but both options erode the decentralization of the network by creating a second-layer protocol on top of Nostr.
+
+## Filters and return values
+
+This NIP defines the verb `COUNT`, which accepts a subscription id and filters as specified in [NIP 01](01.md) for the verb `REQ`. Multiple filters are OR'd together and aggregated into a single count result.
+
+```
+["COUNT", <subscription_id>, <filters JSON>...]
+```
+
+Counts are returned using a `COUNT` response in the form `{"count": <integer>}`. Relays may use probabilistic counts to reduce compute requirements.
+
+```
+["COUNT", <subscription_id>, {"count": <integer>}]
+```
+
+Examples:
+
+```
+# Followers count
+["COUNT", <subscription_id>, {"kinds": [3], "#p": [<pubkey>]}]
+["COUNT", <subscription_id>, {"count": 238}]
+
+# Count posts and reactions
+["COUNT", <subscription_id>, {"kinds": [1, 7], "authors": [<pubkey>]}]
+["COUNT", <subscription_id>, {"count": 5}]
+```