add persistency for mailserver chat requests (#1598)

appdatabase/migrations/bindata.go

@@ -1,7 +1,7 @@
 // Code generated by go-bindata. DO NOT EDIT.
 // sources:
-// 0001_app.down.sql (344B)
-// 0001_app.up.sql (2.701kB)
+// 0001_app.down.sql (387B)
+// 0001_app.up.sql (2.876kB)
 // doc.go (74B)
 
 package migrations
@@ -71,7 +71,7 @@ func (fi bindataFileInfo) Sys() interface{} {
 	return nil
 }
 
-var __0001_appDownSql = []byte("\x1f\x8b\x08\x00\x00\x00\x00\x00\x00\xff\x74\xce\xbd\x0e\xc2\x30\x0c\x04\xe0\xbd\x4f\xd1\xf7\xe8\x04\x6a\x07\x24\x04\x08\x31\xb0\x59\x21\x35\xad\x45\x1b\x07\xdb\xe5\xe7\xed\xd9\x80\x40\xba\x7e\x77\x3a\x5d\xbd\xdf\xee\xca\xc3\x62\xb9\x6e\x4a\x45\x33\x0a\x9d\x56\xc5\x17\x3a\xef\x79\x0a\x96\xe2\x49\xf8\xae\x28\x79\x84\x9e\xd4\x58\x9e\x49\xd8\xba\x18\xd3\x7a\x44\x19\x49\x95\x38\xa4\x6e\xe2\x82\x9e\xff\xc6\x07\xf6\x97\xfc\x33\x30\x86\x4c\x3c\x3a\x1a\x14\xe5\xf6\xbb\xf4\x71\x10\xbc\x4e\xa8\x06\x9d\x7b\x7f\x5b\x6d\xea\xe6\x38\xd7\x01\xdf\x3b\x03\x6a\x81\xda\xc7\xdc\xa6\x71\x24\xaf\x55\xf1\x0a\x00\x00\xff\xff\x89\xe0\x6b\xf0\x58\x01\x00\x00")
+var __0001_appDownSql = []byte("\x1f\x8b\x08\x00\x00\x00\x00\x00\x00\xff\x74\x8e\xcd\x0e\x82\x40\x0c\x84\xef\x3c\x05\xef\xc1\x49\x03\x07\x13\xa3\xc6\x78\xf0\xd6\xac\x4b\x85\x46\xd8\xae\x6d\xf1\xe7\xed\x4d\x4c\xfc\x59\x85\xeb\x37\x93\x6f\xa6\xdc\xae\x37\xf9\x6e\x36\x5f\x56\xb9\xa2\x19\x85\x46\x8b\xec\x0b\x3a\xef\x79\x08\x96\xc2\x83\xf0\x55\x51\xc6\x21\xb4\xa4\xc6\x72\x4f\xc2\xda\xc5\x98\xd6\x23\x4a\x4f\xaa\xc4\x21\xe5\x26\x2e\xe8\xf1\x4f\xde\xb1\x3f\x8d\x3f\x03\x63\x18\x89\x7b\x47\x9d\xa2\x5c\x7e\x4d\x1f\x0e\x82\xe7\x01\xd5\xa0\x71\xef\x6f\x8b\x55\x59\xed\xa7\x3a\xe0\x5b\x67\x40\x35\x50\x7d\x9b\x72\x1a\x47\xf2\x93\x8b\x4f\xc1\x4b\x29\x2e\x34\xa8\x45\xf6\x08\x00\x00\xff\xff\xef\x20\x3b\x16\x83\x01\x00\x00")
 
 func _0001_appDownSqlBytes() ([]byte, error) {
 	return bindataRead(
@@ -86,12 +86,12 @@ func _0001_appDownSql() (*asset, error) {
 		return nil, err
 	}
 
-	info := bindataFileInfo{name: "0001_app.down.sql", size: 344, mode: os.FileMode(0644), modTime: time.Unix(1567620215, 0)}
-	a := &asset{bytes: bytes, info: info, digest: [32]uint8{0xa0, 0x74, 0x22, 0xcd, 0xfd, 0xf3, 0xf1, 0x2a, 0xa0, 0xc1, 0x37, 0x66, 0x32, 0x93, 0x2c, 0x75, 0x21, 0xd6, 0xd7, 0xb2, 0x37, 0x7c, 0x2, 0x4c, 0xab, 0xab, 0x4c, 0x5d, 0x55, 0x6c, 0x77, 0xf2}}
+	info := bindataFileInfo{name: "0001_app.down.sql", size: 387, mode: os.FileMode(0644), modTime: time.Unix(1567701212, 0)}
+	a := &asset{bytes: bytes, info: info, digest: [32]uint8{0xbc, 0x9c, 0xd2, 0xe1, 0x1d, 0x8, 0x34, 0x6a, 0xc8, 0x37, 0x13, 0xb3, 0x9f, 0x26, 0x23, 0x33, 0xd4, 0x25, 0x8, 0xed, 0x53, 0xe6, 0xd, 0x46, 0xc9, 0xf4, 0x24, 0xf8, 0x1, 0x1f, 0xf5, 0xc8}}
 	return a, nil
 }
 
-var __0001_appUpSql = []byte("\x1f\x8b\x08\x00\x00\x00\x00\x00\x00\xff\xa4\x56\xc1\x92\xaa\x3a\x10\xdd\xf3\x15\xbd\xd4\x2a\x36\x6f\x3d\x2b\xd4\xe8\x50\x8f\x07\xef\x22\xde\x99\x59\xa5\x22\x44\xa5\x04\x92\x49\xe2\x38\xfe\xfd\xad\x00\x01\x54\xc0\xb1\xee\x8e\xa4\x3b\xc7\x73\x4e\x77\x3a\xce\x43\xe4\x44\x08\x22\x67\xe6\x21\x70\x97\xe0\x07\x11\xa0\x77\x77\x1d\xad\x41\x52\xa5\xd2\x62\x2f\x61\x62\xa9\x0b\xa7\xf0\xdb\x09\xe7\xaf\x4e\x08\xff\x87\xee\x7f\x4e\xf8\x01\xff\xa2\x0f\xdb\xfa\x22\xd9\x89\xc2\xcc\x0b\x66\xd6\x14\xde\xdc\xe8\x35\xd8\x44\x10\x06\x6f\xee\xe2\xc5\xb2\x46\xc0\x49\x1c\xb3\x53\xa1\x34\x38\x49\x12\x41\xa5\xec\xc7\x3f\x93\x2c\xa3\x0a\x66\x41\xe0\x21\xc7\xb7\xad\xf8\x40\x3a\xab\x92\x57\x84\xde\x23\xdb\x92\x8a\x09\xb2\x37\x2b\x7e\xda\x1e\xe9\xa5\xe4\x65\x5b\x9c\xa8\x43\xbd\x5f\x90\xdc\xa4\xc4\x2c\x63\xa2\xfc\x1e\x66\xbe\xf1\xdd\x5f\x1b\x04\xae\xbf\x40\xef\x70\x2a\xd2\xcf\x13\xc5\x15\x23\x6c\x58\x07\x7e\x47\x4b\x15\x9b\xc2\xdb\x2b\x0a\x51\xb3\x7c\x19\x83\xd3\x82\xfa\xc1\x74\xa4\x81\x2a\x17\xe3\x96\x6e\x05\x3b\x4b\x2a\xb4\xa5\x69\x52\x0a\xbb\xb6\xb2\xd1\x5e\x1e\xf2\x37\x9e\x67\x5b\x2a\xcd\xa9\x54\x24\xe7\xb0\x59\xaf\xdc\x95\x8f\x16\x30\x73\x57\xae\x1f\xd9\x56\x42\x38\x37\x4e\xc3\x02\x2d\x9d\x8d\x17\xc1\x8e\x64\x92\xda\xd6\x21\xd5\x76\x5f\xdc\x22\xa1\xdf\xb0\xf1\xd7\xd5\x49\xd7\x1f\xb1\x72\x8c\x31\xae\xf1\x60\x62\xd5\x5b\xd8\x28\x68\xa9\x9a\x9c\xaa\x7a\xcb\x20\x44\xee\xca\xd7\xca\x26\xed\x99\x29\x84\x68\x89\x42\xe4\xcf\x51\x8b\x3e\xd1\xfb\x81\xd6\xe0\xa1\x08\xc1\xdc\x59\xcf\x9d\x05\xb2\x1e\xb8\xa9\xe5\x6b\x2b\x5b\xd7\x3a\x66\x3e\x27\x93\x53\x91\xa7\x52\xa6\xac\xd0\x80\x1a\x18\xf7\xd5\xa2\x4d\xbb\x8d\x74\xc5\x36\xc7\xaf\xb4\x96\x6c\x27\xd5\x76\xbf\xd4\x31\x82\x4a\x90\x42\xee\xaa\xd6\x29\xa8\x3a\x33\x71\xd4\x05\x68\x0a\x5b\xb5\x44\xb7\x16\x44\x1e\x9a\xfb\xda\x6e\xdf\xde\xe4\x36\xb2\xcd\x8e\x78\xe0\x90\xfa\xae\xaf\xa9\xa4\x45\x42\x45\x4f\x86\xa0\x31\x4d\xb9\xaa\xd3\x32\xb6\xaf\xbf\xae\xa6\x52\xbf\x5b\xad\x1a\xdb\x50\xb8\xee\x91\x8c\xc5\x47\xd9\x4d\xab\x52\xee\x3c\xb4\xad\x79\xe0\xaf\xa3\xd0\xd1\x46\xd4\x57\xd7\xd8\x86\x39\x15\xe6\x0a\x97\xdf\x35\x9c\xb9\xef\x13\x8d\x69\xd7\x09\x76\xfb\x5b\xd3\x47\x3d\x58\xb1\xfb\xcb\xa2\x14\xa7\x7c\x4b\xc5\x7d\x7a\xe7\xea\x0f\x43\x52\x92\x94\x33\xa0\x19\x00\x4b\xc7\x5b\xf7\x9a\x51\x72\xed\x55\x7f\x6b\xee\xe0\xe1\x8a\xe9\x23\x8c\x2a\xeb\xa1\x77\x66\x8e\x62\xc5\xf0\x73\x3e\x8e\x77\xf1\x90\x9d\xf2\x52\xc4\x50\x0e\xce\x91\xfe\xab\xb9\x8f\x77\xa0\x49\xfa\x51\x0f\xe6\x84\xf3\xb4\xd8\xe3\x1d\x13\xb8\x96\xdc\x28\xee\x75\xd2\xb4\x61\x4b\xe7\x99\x8e\xcc\x49\x9a\x49\x2a\xbe\xaa\x59\x01\x00\x90\x26\xfd\x0f\xb7\x8e\x95\x53\xee\xde\x46\x1d\x1a\x36\x59\x47\x39\x91\xf2\xcc\x44\x03\x5d\xed\xee\x32\x4a\xd5\xdd\x89\xe7\x66\x71\x2b\x00\x0b\xfa\x79\xa2\x52\xe1\x3d\xe1\x46\xcc\x9e\x70\xbc\x13\x2c\xbf\x7a\xd3\xd0\x0a\xdd\xf2\xd3\x79\x8a\x3d\xca\xea\x7d\x85\x75\xa0\x7c\xf3\x6f\x5f\xb8\x61\x1d\xd5\xff\x85\x01\xe6\xb8\x06\xc3\x69\xf2\xad\x5b\x66\x50\x60\x9d\xf7\xe3\x02\x63\xc5\x78\x1a\x1b\x67\xca\xc5\x70\xa5\x6b\x70\x79\x5d\xb0\x8c\x48\x65\x58\x34\x1e\x99\x49\xf2\xcf\xbd\xe0\x3f\x01\x00\x00\xff\xff\xa9\x9c\x70\x28\x8d\x0a\x00\x00")
+var __0001_appUpSql = []byte("\x1f\x8b\x08\x00\x00\x00\x00\x00\x00\xff\xa4\x56\x4d\x93\xaa\x38\x14\xdd\xf3\x2b\xb2\xd4\x2a\x36\xb3\x7e\x2b\xd4\x68\x53\xc3\xc0\x0c\xe2\x74\xbf\x55\x2a\x42\x44\x4a\x20\xbc\x24\xb6\xed\xbf\x9f\xca\x17\xa0\x02\xb6\xf3\x76\x24\xf7\xe6\x78\xce\xb9\x37\x37\x2e\x63\xe8\x25\x10\x24\xde\x22\x80\xc0\x5f\x83\x30\x4a\x00\xfc\xf0\xb7\xc9\x16\x70\x22\x44\x51\xe7\x1c\xcc\x1c\x71\x6d\x08\xf8\xd7\x8b\x97\x6f\x5e\x0c\xfe\x8e\xfd\xbf\xbc\xf8\x27\xf8\x13\xfe\x74\x9d\x4f\x5c\x9e\x09\x58\x04\xd1\xc2\x99\x83\x77\x3f\x79\x8b\x76\x09\x88\xa3\x77\x7f\xf5\xc3\x71\x26\xc0\x71\x9a\xd2\x73\x2d\x24\x38\xce\x32\x46\x38\x1f\xc6\xbf\xe0\xb2\x24\x02\x2c\xa2\x28\x80\x5e\xe8\x3a\xe9\x11\xf7\x56\x8a\x57\x02\x3f\x12\xd7\xe1\x82\x32\x9c\xdb\x55\x73\xde\x9f\xc8\x55\xf1\x72\x9d\x06\x8b\xa3\xd9\xaf\x71\x65\x53\x52\x5a\x52\xa6\xbe\xc7\x99\xef\x42\xff\x9f\x1d\x04\x7e\xb8\x82\x1f\xe0\x5c\x17\xbf\xce\x04\x69\x46\xc8\xb2\x8e\xc2\x9e\x16\x1d\x9b\x83\xf7\x37\x18\xc3\x76\xf9\x63\x0a\x4e\x0a\x1a\x06\x93\x91\x16\x4a\x2d\xa6\x2d\xdd\x33\x7a\xe1\x84\x49\x4b\x8b\x4c\x09\xbb\xb5\xb2\xd5\xae\x0e\x85\xbb\x20\x70\x1d\x51\x54\x84\x0b\x5c\x35\x60\xb7\xdd\xf8\x9b\x10\xae\xc0\xc2\xdf\xf8\x61\xe2\x3a\x19\x6e\x1a\xeb\x34\x58\xc1\xb5\xb7\x0b\x12\x70\xc0\x25\x27\xae\x73\x2c\xa4\xdd\x57\xbf\xce\xc8\x17\xd8\x85\x5b\x7d\xd2\x0f\x27\xac\x9c\x62\x8c\x0c\x1e\x98\x39\x66\x0b\x59\x05\x1d\x55\x9b\xa3\xab\xb7\x8e\x62\xe8\x6f\x42\xa9\x6c\xd6\x9d\x99\x83\x18\xae\x61\x0c\xc3\x25\xec\xd0\x67\x72\x3f\x92\x1a\x02\x98\x40\xb0\xf4\xb6\x4b\x6f\x05\x9d\x27\x6e\x4a\xf9\xd2\xca\xce\xb5\x9e\x99\xaf\xc9\x6c\x08\xab\x0a\xce\x0b\x5a\x4b\x40\x09\x8c\x86\x6a\xd1\xa5\xdd\x47\xfa\x62\xdb\xe3\x37\x5a\x15\xdb\x99\xde\x1e\x96\x3a\x45\x50\x30\x5c\xf3\x83\x6e\x9d\x9a\x88\x0b\x65\x27\x59\x80\xb6\xb0\xba\x25\xfa\xb5\xc0\xfc\xd8\xde\xd7\x6e\xfb\xfe\x26\x77\x91\x7d\x79\x42\x23\x87\xc4\x97\xb9\xa6\x9c\xd4\x19\x61\x03\x19\x8c\xa4\xa4\x68\x84\x49\x2b\x69\x6e\xbe\x6e\xa6\xd2\xb0\x5b\x9d\x1a\xd7\x52\xb8\xed\x91\x92\xa6\x27\xde\x4f\xd3\x29\x0f\x1e\xba\xce\x32\x0a\xb7\x49\xec\x49\x23\xcc\xd5\xb5\xb6\xa1\x86\x30\x7b\x85\xd5\xb7\x81\xb3\xf7\x7d\x26\x31\x5d\x93\xe0\x76\xbf\x35\x7f\xd6\x83\x9a\xdd\x6f\x16\xa5\x3e\x57\x7b\xc2\x1e\xd3\x7b\x57\x7f\x1c\x92\xe0\x4c\xcd\x80\x76\x00\xac\xbd\x60\x3b\x68\x86\xe2\x3a\xa8\xfe\xde\xdc\xd1\xc3\x9a\xe9\x33\x0c\x9d\xf5\xd4\x3b\x3b\x47\x91\xa0\xe8\x35\x1f\xa7\xbb\x78\xcc\x4e\x7e\xad\x53\xa0\x06\xe7\x44\xff\x19\xee\xd3\x1d\x68\x93\xbe\xd5\x83\x15\x6e\x9a\xa2\xce\xd1\x81\x32\x64\x24\xb7\x8a\x07\x9d\xb4\x6d\xd8\xd1\x79\xa5\x23\x2b\x5c\x94\x9c\xb0\x4f\x3d\x2b\x00\x00\xa0\xc8\x86\x1f\x6e\x19\x53\x53\xee\xd1\x46\x19\x1a\x37\x59\x46\x1b\xcc\xf9\x85\xb2\x16\x5a\xef\x1e\x4a\x42\xc4\xc3\x89\xd7\x66\x71\x27\x00\x31\xf2\xeb\x4c\xb8\x40\x39\x6e\xac\x98\x1c\x37\xe8\xc0\x68\x75\xf3\xa6\xc1\x0d\xbc\xe7\x27\xf3\x04\x7d\x96\x35\xf8\x0a\xcb\x80\x7a\xf3\xef\x5f\xb8\x71\x1d\xfa\xff\xc2\x08\x73\x64\xc0\x50\x91\x7d\xc9\x96\x19\x15\x68\xf2\xbe\x5d\x60\x24\x68\x53\xa4\xd6\x19\xb5\x18\xaf\xb4\x01\xe7\xb7\x05\x2b\x31\x17\x96\x45\xeb\x91\x9d\x24\x7f\xfc\xef\xc2\xa9\x1f\xb3\xe2\x18\xae\x73\x62\x59\x5a\x63\x47\x79\x96\xf4\x42\x3a\x4e\xba\xd6\x86\x98\x4e\x38\x16\xf9\xb1\x9f\x21\xa8\x8d\x3f\xd2\xfd\x2f\x00\x00\xff\xff\x86\xe7\xc8\x0b\x3c\x0b\x00\x00")
 
 func _0001_appUpSqlBytes() ([]byte, error) {
 	return bindataRead(
@@ -106,8 +106,8 @@ func _0001_appUpSql() (*asset, error) {
 		return nil, err
 	}
 
-	info := bindataFileInfo{name: "0001_app.up.sql", size: 2701, mode: os.FileMode(0644), modTime: time.Unix(1567620191, 0)}
-	a := &asset{bytes: bytes, info: info, digest: [32]uint8{0x36, 0xdf, 0xa0, 0x6b, 0x3f, 0x6a, 0x1, 0xa, 0x8, 0xae, 0x78, 0xe5, 0xea, 0x9c, 0x51, 0xcf, 0xef, 0x46, 0x16, 0xad, 0xa0, 0xc6, 0x98, 0xb4, 0xd1, 0xd2, 0xbd, 0x18, 0x1f, 0xe0, 0x16, 0x8f}}
+	info := bindataFileInfo{name: "0001_app.up.sql", size: 2876, mode: os.FileMode(0644), modTime: time.Unix(1567701215, 0)}
+	a := &asset{bytes: bytes, info: info, digest: [32]uint8{0xed, 0x65, 0x8f, 0x50, 0xd3, 0x89, 0x74, 0x2e, 0x23, 0x73, 0x25, 0xbe, 0x5b, 0x53, 0x39, 0x3f, 0x4a, 0x65, 0x55, 0x39, 0x20, 0x10, 0xaa, 0xa6, 0xb9, 0xd0, 0x4c, 0xfa, 0x86, 0xaf, 0xac, 0xb0}}
 	return a, nil
 }
 

appdatabase/migrations/sql/0001_app.down.sql

@@ -11,3 +11,4 @@ DROP TABLE mailservers;
 DROP TABLE mailserver_request_gaps;
 DROP INDEX mailserver_request_gaps_chat_id_idx;
 DROP TABLE mailserver_topics;
+DROP TABLE mailserver_chat_request_ranges;

appdatabase/migrations/sql/0001_app.up.sql

@@ -98,3 +98,9 @@ CREATE TABLE IF NOT EXISTS mailserver_topics (
     chat_ids VARCHAR,
     last_request INTEGER DEFAULT 1
 ) WITHOUT ROWID;
+
+CREATE TABLE IF NOT EXISTS mailserver_chat_request_ranges (
+    chat_id VARCHAR PRIMARY KEY,
+    lowest_request_from INTEGER,
+    highest_request_to INTEGER
+) WITHOUT ROWID;

services/mailservers/README.md

@@ -97,3 +97,22 @@ Reads all saved mailserver topics.
 #### mailservers_deleteMailserverTopic
 
 Deletes a mailserver topic using `topic` as an identifier.
+
+#### mailservers_addChatRequestRange
+
+Stores `ChatRequestRange` in the database.
+```json
+{
+    "chat-id": "chat-id-001",
+    "lowest-request-from": 1567693421154,
+    "highest-request-to": 1567693576779 
+}
+```
+
+#### mailservers_getChatRequestRanges
+
+Reads all saved chat request ranges.
+
+#### mailservers_deleteChatRequestRange
+
+Deletes a chat request range by `chat-id`.

services/mailservers/api.go

@@ -50,3 +50,15 @@ func (a *API) GetMailserverTopics(ctx context.Context) ([]MailserverTopic, error
 func (a *API) DeleteMailserverTopic(ctx context.Context, topic string) error {
 	return a.db.DeleteTopic(topic)
 }
+
+func (a *API) AddChatRequestRange(ctx context.Context, req ChatRequestRange) error {
+	return a.db.AddChatRequestRange(req)
+}
+
+func (a *API) GetChatRequestRanges(ctx context.Context) ([]ChatRequestRange, error) {
+	return a.db.ChatRequestRanges()
+}
+
+func (a *API) DeleteChatRequestRange(ctx context.Context, chatID string) error {
+	return a.db.DeleteChatRequestRange(chatID)
+}

services/mailservers/api_test.go

@@ -131,3 +131,36 @@ func TestAddGetDeleteMailserverTopics(t *testing.T) {
 	err = api.DeleteMailserverTopic(context.Background(), "non-existing-topic")
 	require.NoError(t, err)
 }
+
+func TestAddGetDeleteChatRequestRanges(t *testing.T) {
+	db, close := setupTestDB(t)
+	defer close()
+	api := &API{db: db}
+	chatRequestRange1 := ChatRequestRange{
+		ChatID:            "chat-id-001",
+		LowestRequestFrom: 123,
+		HighestRequestTo:  456,
+	}
+	chatRequestRange2 := chatRequestRange1
+	chatRequestRange2.ChatID = "chat-id-002"
+
+	err := api.AddChatRequestRange(context.Background(), chatRequestRange1)
+	require.NoError(t, err)
+	err = api.AddChatRequestRange(context.Background(), chatRequestRange2)
+	require.NoError(t, err)
+
+	// Verify topics were added.
+	ranges, err := api.GetChatRequestRanges(context.Background())
+	require.NoError(t, err)
+	require.EqualValues(t, []ChatRequestRange{chatRequestRange1, chatRequestRange2}, ranges)
+
+	err = api.DeleteChatRequestRange(context.Background(), chatRequestRange1.ChatID)
+	require.NoError(t, err)
+	ranges, err = api.GetChatRequestRanges(context.Background())
+	require.NoError(t, err)
+	require.EqualValues(t, []ChatRequestRange{chatRequestRange2}, ranges)
+
+	// Delete non-existing topic.
+	err = api.DeleteChatRequestRange(context.Background(), "non-existing-chat-id")
+	require.NoError(t, err)
+}

services/mailservers/database.go

@@ -38,6 +38,12 @@ type MailserverTopic struct {
 	LastRequest int      `json:"last-request"` // default is 1
 }
 
+type ChatRequestRange struct {
+	ChatID            string `json:"chat-id"`
+	LowestRequestFrom int    `json:"lowest-request-from"`
+	HighestRequestTo  int    `json:"highest-request-to"`
+}
+
 // sqlStringSlice helps to serialize a slice of strings into a single column using JSON serialization.
 type sqlStringSlice []string
 
@@ -246,3 +252,44 @@ func (d *Database) DeleteTopic(topic string) error {
 	_, err := d.db.Exec(`DELETE FROM mailserver_topics WHERE topic = ?`, topic)
 	return err
 }
+
+func (d *Database) AddChatRequestRange(req ChatRequestRange) error {
+	_, err := d.db.Exec(`INSERT OR REPLACE INTO mailserver_chat_request_ranges(
+			chat_id,
+			lowest_request_from,
+			highest_request_to
+		) VALUES (?, ?, ?)`,
+		req.ChatID,
+		req.LowestRequestFrom,
+		req.HighestRequestTo,
+	)
+	return err
+}
+
+func (d *Database) ChatRequestRanges() ([]ChatRequestRange, error) {
+	var result []ChatRequestRange
+
+	rows, err := d.db.Query(`SELECT chat_id, lowest_request_from, highest_request_to FROM mailserver_chat_request_ranges`)
+	if err != nil {
+		return nil, err
+	}
+
+	for rows.Next() {
+		var req ChatRequestRange
+		if err := rows.Scan(
+			&req.ChatID,
+			&req.LowestRequestFrom,
+			&req.HighestRequestTo,
+		); err != nil {
+			return nil, err
+		}
+		result = append(result, req)
+	}
+
+	return result, nil
+}
+
+func (d *Database) DeleteChatRequestRange(chatID string) error {
+	_, err := d.db.Exec(`DELETE FROM mailserver_chat_request_ranges WHERE chat_id = ?`, chatID)
+	return err
+}