refactor server to allow pluggable db and tracing (#1036)

* refactor server to allow pluggable db and tracing

* clean up

* fix descriptions

* remove dependencies

12 files changed, 170 insertions, 0 deletions

diff --git a/atuin-server-postgres/migrations/20210425153745_create_history.sql b/atuin-server-postgres/migrations/20210425153745_create_history.sql
new file mode 100644
index 00000000..2c2d17b0
--- /dev/null
+++ b/atuin-server-postgres/migrations/20210425153745_create_history.sql
@@ -0,0 +1,11 @@
+create table history (
+	id bigserial primary key,
+	client_id text not null unique, -- the client-generated ID
+	user_id bigserial not null,     -- allow multiple users
+	hostname text not null,         -- a unique identifier from the client (can be hashed, random, whatever)
+	timestamp timestamp not null,   -- one of the few non-encrypted metadatas
+
+	data varchar(8192) not null,    -- store the actual history data, encrypted. I don't wanna know!
+
+	created_at timestamp not null default current_timestamp
+);
diff --git a/atuin-server-postgres/migrations/20210425153757_create_users.sql b/atuin-server-postgres/migrations/20210425153757_create_users.sql
new file mode 100644
index 00000000..a25dcced
--- /dev/null
+++ b/atuin-server-postgres/migrations/20210425153757_create_users.sql
@@ -0,0 +1,10 @@
+create table users (
+	id bigserial primary key,               -- also store our own ID
+	username varchar(32) not null unique,   -- being able to contact users is useful
+	email varchar(128) not null unique,     -- being able to contact users is useful
+	password varchar(128) not null unique
+);
+
+-- the prior index is case sensitive :(
+CREATE UNIQUE INDEX email_unique_idx on users (LOWER(email));
+CREATE UNIQUE INDEX username_unique_idx on users (LOWER(username));
diff --git a/atuin-server-postgres/migrations/20210425153800_create_sessions.sql b/atuin-server-postgres/migrations/20210425153800_create_sessions.sql
new file mode 100644
index 00000000..c2fb6559
--- /dev/null
+++ b/atuin-server-postgres/migrations/20210425153800_create_sessions.sql
@@ -0,0 +1,6 @@
+-- Add migration script here
+create table sessions (
+	id bigserial primary key,
+	user_id bigserial,
+	token varchar(128) unique not null
+);
diff --git a/atuin-server-postgres/migrations/20220419082412_add_count_trigger.sql b/atuin-server-postgres/migrations/20220419082412_add_count_trigger.sql
new file mode 100644
index 00000000..dd1afa88
--- /dev/null
+++ b/atuin-server-postgres/migrations/20220419082412_add_count_trigger.sql
@@ -0,0 +1,51 @@
+-- Prior to this, the count endpoint was super naive and just ran COUNT(1). 
+-- This is slow asf. Now that we have an amount of actual traffic, 
+-- stop doing that!
+-- This basically maintains a count, so we can read ONE row, instead of ALL the
+-- rows. Much better.
+-- Future optimisation could use some sort of cache so we don't even need to hit
+-- postgres at all.
+
+create table total_history_count_user(
+	id bigserial primary key, 
+	user_id bigserial,
+	total integer -- try and avoid using keywords - hence total, not count
+);
+
+create or replace function user_history_count()
+returns trigger as 
+$func$
+begin
+	if (TG_OP='INSERT') then
+		update total_history_count_user set total = total + 1 where user_id = new.user_id;
+
+		if not found then
+			insert into total_history_count_user(user_id, total) 
+			values (
+				new.user_id, 
+				(select count(1) from history where user_id = new.user_id)
+			);
+		end if;
+		
+	elsif (TG_OP='DELETE') then
+		update total_history_count_user set total = total - 1 where user_id = new.user_id;
+
+		if not found then
+			insert into total_history_count_user(user_id, total) 
+			values (
+				new.user_id, 
+				(select count(1) from history where user_id = new.user_id)
+			);
+		end if;
+	end if;
+
+	return NEW; -- this is actually ignored for an after trigger, but oh well
+end;
+$func$
+language plpgsql volatile -- pldfplplpflh
+cost 100; -- default value
+
+create trigger tg_user_history_count 
+	after insert or delete on history 
+	for each row 
+	execute procedure user_history_count();
diff --git a/atuin-server-postgres/migrations/20220421073605_fix_count_trigger_delete.sql b/atuin-server-postgres/migrations/20220421073605_fix_count_trigger_delete.sql
new file mode 100644
index 00000000..6198f300
--- /dev/null
+++ b/atuin-server-postgres/migrations/20220421073605_fix_count_trigger_delete.sql
@@ -0,0 +1,35 @@
+-- the old version of this function used NEW in the delete part when it should
+-- use OLD
+
+create or replace function user_history_count()
+returns trigger as 
+$func$
+begin
+	if (TG_OP='INSERT') then
+		update total_history_count_user set total = total + 1 where user_id = new.user_id;
+
+		if not found then
+			insert into total_history_count_user(user_id, total) 
+			values (
+				new.user_id, 
+				(select count(1) from history where user_id = new.user_id)
+			);
+		end if;
+		
+	elsif (TG_OP='DELETE') then
+		update total_history_count_user set total = total - 1 where user_id = old.user_id;
+
+		if not found then
+			insert into total_history_count_user(user_id, total) 
+			values (
+				old.user_id, 
+				(select count(1) from history where user_id = old.user_id)
+			);
+		end if;
+	end if;
+
+	return NEW; -- this is actually ignored for an after trigger, but oh well
+end;
+$func$
+language plpgsql volatile -- pldfplplpflh
+cost 100; -- default value
diff --git a/atuin-server-postgres/migrations/20220421174016_larger-commands.sql b/atuin-server-postgres/migrations/20220421174016_larger-commands.sql
new file mode 100644
index 00000000..0ac43433
--- /dev/null
+++ b/atuin-server-postgres/migrations/20220421174016_larger-commands.sql
@@ -0,0 +1,3 @@
+-- Make it 4x larger. Most commands are less than this, but as it's base64
+-- SOME are more than 8192. Should be enough for now.
+ALTER TABLE history ALTER COLUMN data TYPE varchar(32768);
diff --git a/atuin-server-postgres/migrations/20220426172813_user-created-at.sql b/atuin-server-postgres/migrations/20220426172813_user-created-at.sql
new file mode 100644
index 00000000..a9138194
--- /dev/null
+++ b/atuin-server-postgres/migrations/20220426172813_user-created-at.sql
@@ -0,0 +1 @@
+alter table users add column created_at timestamp not null default now();
diff --git a/atuin-server-postgres/migrations/20220505082442_create-events.sql b/atuin-server-postgres/migrations/20220505082442_create-events.sql
new file mode 100644
index 00000000..57e16ec7
--- /dev/null
+++ b/atuin-server-postgres/migrations/20220505082442_create-events.sql
@@ -0,0 +1,14 @@
+create type event_type as enum ('create', 'delete');
+ 
+create table events (
+	id bigserial primary key,
+	client_id text not null unique, -- the client-generated ID
+	user_id bigserial not null,     -- allow multiple users
+	hostname text not null,         -- a unique identifier from the client (can be hashed, random, whatever)
+	timestamp timestamp not null,   -- one of the few non-encrypted metadatas
+
+	event_type event_type,
+	data text not null,    -- store the actual history data, encrypted. I don't wanna know!
+
+	created_at timestamp not null default current_timestamp
+);
diff --git a/atuin-server-postgres/migrations/20220610074049_history-length.sql b/atuin-server-postgres/migrations/20220610074049_history-length.sql
new file mode 100644
index 00000000..b1c23016
--- /dev/null
+++ b/atuin-server-postgres/migrations/20220610074049_history-length.sql
@@ -0,0 +1,2 @@
+-- Add migration script here
+alter table history alter column data type text;
diff --git a/atuin-server-postgres/migrations/20230315220537_drop-events.sql b/atuin-server-postgres/migrations/20230315220537_drop-events.sql
new file mode 100644
index 00000000..fe3cae17
--- /dev/null
+++ b/atuin-server-postgres/migrations/20230315220537_drop-events.sql
@@ -0,0 +1,2 @@
+-- Add migration script here
+drop table events;
diff --git a/atuin-server-postgres/migrations/20230315224203_create-deleted.sql b/atuin-server-postgres/migrations/20230315224203_create-deleted.sql
new file mode 100644
index 00000000..9a9e6263
--- /dev/null
+++ b/atuin-server-postgres/migrations/20230315224203_create-deleted.sql
@@ -0,0 +1,5 @@
+-- Add migration script here
+alter table history add column if not exists deleted_at timestamp;
+
+-- queries will all be selecting the ids of history for a user, that has been deleted
+create index if not exists history_deleted_index on history(client_id, user_id, deleted_at);
diff --git a/atuin-server-postgres/migrations/20230515221038_trigger-delete-only.sql b/atuin-server-postgres/migrations/20230515221038_trigger-delete-only.sql
new file mode 100644
index 00000000..3d0bba52
--- /dev/null
+++ b/atuin-server-postgres/migrations/20230515221038_trigger-delete-only.sql
@@ -0,0 +1,30 @@
+-- We do not need to run the trigger on deletes, as the only time we are deleting history is when the user
+-- has already been deleted
+-- This actually slows down deleting all the history a good bit!
+
+create or replace function user_history_count()
+returns trigger as 
+$func$
+begin
+	if (TG_OP='INSERT') then
+		update total_history_count_user set total = total + 1 where user_id = new.user_id;
+
+		if not found then
+			insert into total_history_count_user(user_id, total) 
+			values (
+				new.user_id, 
+				(select count(1) from history where user_id = new.user_id)
+			);
+		end if;
+	end if;
+
+	return NEW; -- this is actually ignored for an after trigger, but oh well
+end;
+$func$
+language plpgsql volatile -- pldfplplpflh
+cost 100; -- default value
+
+create or replace trigger tg_user_history_count 
+	after insert on history 
+	for each row 
+	execute procedure user_history_count();