Preset tables, latest workspace view, state logic improved

Signed-off-by: Danny Kopping <danny@coder.com>

coderd/database/migrations/000290_prebuilds.down.sql

@@ -1,6 +1,7 @@
 -- Revert prebuild views
 DROP VIEW IF EXISTS workspace_prebuild_builds;
 DROP VIEW IF EXISTS workspace_prebuilds;
+DROP VIEW IF EXISTS workspace_latest_build;
 
 -- Revert user operations
 DELETE FROM user_status_changes WHERE user_id = 'c42fdf75-3097-471c-8c33-fb52454d81c0';

coderd/database/migrations/000290_prebuilds.up.sql

@@ -12,3 +12,17 @@ CREATE VIEW workspace_prebuild_builds AS
 SELECT workspace_id
 FROM workspace_builds
 WHERE initiator_id = 'c42fdf75-3097-471c-8c33-fb52454d81c0';
+
+CREATE VIEW workspace_latest_build AS
+SELECT wb.*
+FROM (SELECT tv.template_id,
+			 wbmax.workspace_id,
+			 MAX(wbmax.build_number) as max_build_number
+	  FROM workspace_builds wbmax
+			   JOIN template_versions tv ON (tv.id = wbmax.template_version_id)
+	  GROUP BY tv.template_id, wbmax.workspace_id) wbmax
+		 JOIN workspace_builds wb ON (
+	wb.workspace_id = wbmax.workspace_id
+		AND wb.build_number = wbmax.max_build_number
+	);
+

coderd/database/migrations/000291_preset_prebuilds.down.sql

@@ -0,0 +1,3 @@
+DROP TABLE IF EXISTS template_version_preset_prebuild_schedules;
+DROP TABLE IF EXISTS template_version_preset_prebuilds;
+

coderd/database/migrations/000291_preset_prebuilds.up.sql

@@ -1 +1,21 @@
-CREATE TABLE
+CREATE TABLE template_version_preset_prebuilds
+(
+	id                    UUID PRIMARY KEY,
+	preset_id             UUID NOT NULL,
+	desired_instances     INT  NOT NULL,
+	invalidate_after_secs INT  NULL DEFAULT 0,
+
+	-- Deletion should never occur, but if we allow it we should check no prebuilds exist attached to this preset first.
+	FOREIGN KEY (preset_id) REFERENCES template_version_presets (id) ON DELETE CASCADE
+);
+
+CREATE TABLE template_version_preset_prebuild_schedules
+(
+	id                 UUID PRIMARY KEY,
+	preset_prebuild_id UUID NOT NULL,
+	timezone           TEXT NOT NULL,
+	cron_schedule      TEXT NOT NULL,
+	desired_instances  INT  NOT NULL,
+
+	FOREIGN KEY (preset_prebuild_id) REFERENCES template_version_preset_prebuilds (id) ON DELETE CASCADE
+);