[performance] cache recently allowed/denied domains to cut down on db calls (#794)

* fetch creation and fetching domain blocks from db

Signed-off-by: kim <grufwub@gmail.com>

* add separate domainblock cache type, handle removing block from cache on delete

Signed-off-by: kim <grufwub@gmail.com>

* fix sentinel nil values being passed into cache

Signed-off-by: kim <grufwub@gmail.com>

Signed-off-by: kim <grufwub@gmail.com>

internal/cache/domain.go

@@ -0,0 +1,106 @@
+/*
+   GoToSocial
+   Copyright (C) 2021-2022 GoToSocial Authors admin@gotosocial.org
+
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU Affero General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU Affero General Public License for more details.
+
+   You should have received a copy of the GNU Affero General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+package cache
+
+import (
+	"time"
+
+	"codeberg.org/gruf/go-cache/v2"
+	"github.com/superseriousbusiness/gotosocial/internal/gtsmodel"
+)
+
+// DomainCache is a cache wrapper to provide URL and URI lookups for gtsmodel.Status
+type DomainBlockCache struct {
+	cache cache.LookupCache[string, string, *gtsmodel.DomainBlock]
+}
+
+// NewStatusCache returns a new instantiated statusCache object
+func NewDomainBlockCache() *DomainBlockCache {
+	c := &DomainBlockCache{}
+	c.cache = cache.NewLookup(cache.LookupCfg[string, string, *gtsmodel.DomainBlock]{
+		RegisterLookups: func(lm *cache.LookupMap[string, string]) {
+			lm.RegisterLookup("id")
+		},
+
+		AddLookups: func(lm *cache.LookupMap[string, string], block *gtsmodel.DomainBlock) {
+			// Block can be equal to nil when sentinel
+			if block != nil && block.ID != "" {
+				lm.Set("id", block.ID, block.Domain)
+			}
+		},
+
+		DeleteLookups: func(lm *cache.LookupMap[string, string], block *gtsmodel.DomainBlock) {
+			// Block can be equal to nil when sentinel
+			if block != nil && block.ID != "" {
+				lm.Delete("id", block.ID)
+			}
+		},
+	})
+	c.cache.SetTTL(time.Minute*5, false)
+	c.cache.Start(time.Second * 10)
+	return c
+}
+
+// GetByID attempts to fetch a status from the cache by its ID, you will receive a copy for thread-safety
+func (c *DomainBlockCache) GetByID(id string) (*gtsmodel.DomainBlock, bool) {
+	return c.cache.GetBy("id", id)
+}
+
+// GetByURL attempts to fetch a status from the cache by its URL, you will receive a copy for thread-safety
+func (c *DomainBlockCache) GetByDomain(domain string) (*gtsmodel.DomainBlock, bool) {
+	return c.cache.Get(domain)
+}
+
+// Put places a status in the cache, ensuring that the object place is a copy for thread-safety
+func (c *DomainBlockCache) Put(domain string, block *gtsmodel.DomainBlock) {
+	if domain == "" {
+		panic("invalid domain")
+	}
+
+	if block == nil {
+		// This is a sentinel value for (no block)
+		c.cache.Set(domain, nil)
+	} else {
+		// This is a valid domain block
+		c.cache.Set(domain, copyDomainBlock(block))
+	}
+}
+
+// InvalidateByDomain will invalidate a domain block from the cache by domain name.
+func (c *DomainBlockCache) InvalidateByDomain(domain string) {
+	c.cache.Invalidate(domain)
+}
+
+// copyStatus performs a surface-level copy of status, only keeping attached IDs intact, not the objects.
+// due to all the data being copied being 99% primitive types or strings (which are immutable and passed by ptr)
+// this should be a relatively cheap process
+func copyDomainBlock(block *gtsmodel.DomainBlock) *gtsmodel.DomainBlock {
+	return &gtsmodel.DomainBlock{
+		ID:                 block.ID,
+		CreatedAt:          block.CreatedAt,
+		UpdatedAt:          block.UpdatedAt,
+		Domain:             block.Domain,
+		CreatedByAccountID: block.CreatedByAccountID,
+		CreatedByAccount:   nil,
+		PrivateComment:     block.PrivateComment,
+		PublicComment:      block.PublicComment,
+		Obfuscate:          block.Obfuscate,
+		SubscriptionID:     block.SubscriptionID,
+	}
+}