Added a functionning url shortening service

1 files changed, 79 insertions, 0 deletions

diff --git a/src/database.nim b/src/database.nim
new file mode 100644
index 0000000..8094f31
--- /dev/null
+++ b/src/database.nim
@@ -0,0 +1,79 @@
+import tiny_sqlite
+import std / [options, times]
+
+import dbUtils
+
+const migrations = [
+  """
+  CREATE TABLE schema_version (
+    version INTEGER NOT NULL
+  );
+  CREATE TABLE url (
+    id INTEGER PRIMARY KEY,
+    token TEXT NOT NULL UNIQUE,
+    title TEXT NOT NULL,
+    url TEXT,
+    created DATE,
+    expires DATE
+  );
+  CREATE UNIQUE INDEX idx_url_token ON url(token);
+  """
+]
+const latestVersion = migrations.len
+
+proc Migrate*(db: DbConn): bool {.raises: [].} =
+  var currentVersion : int
+  try:
+    currentVersion = db.value("SELECT version FROM schema_version;").get().fromDbValue(int)
+  except SqliteError:
+    discard
+  if currentVersion != latestVersion:
+    try:
+      db.exec("BEGIN")
+      for v in currentVersion..<latestVersion:
+        db.execScript(migrations[v])
+      db.exec("DELETE FROM schema_version;")
+      db.exec("INSERT INTO schema_version (version) VALUES (?);", latestVersion)
+      db.exec("COMMIT;")
+    except:
+      let msg = getCurrentExceptionMsg()
+      echo msg
+      try:
+        db.exec("ROLLBACK")
+      except SqliteError:
+        discard
+      return false
+  return true
+
+type ShortUrl* = object
+  ID*: int
+  Token*: string
+  Title*: string
+  Url*: string
+  Created*: DateTime
+  Expires*: DateTime
+
+proc AddUrl*(db: DbConn, url: ShortUrl) {.raises: [SqliteError].} =
+  let stmt = db.stmt("""
+    INSERT INTO url(token, title, url, created, expires)
+    VALUES (?, ?, ?, ?, ?);
+  """)
+  stmt.exec(url.Token, url.Title, url.Url, url.Created, $url.Expires)
+
+proc GetUrl*(db: DbConn, token: string): ref ShortUrl {.raises: [SqliteError].} =
+  let stmt = db.stmt("SELECT id, title, url, created, expires FROM url WHERE token = ?")
+  for row in stmt.iterate(token):
+    new(result)
+    result.ID = row[0].fromDbValue(int)
+    result.Token = token
+    result.Title = row[1].fromDbValue(string)
+    result.Url = row[2].fromDbValue(string)
+    result.Created = row[3].fromDbValue(DateTime)
+    result.Expires = row[4].fromDbValue(DateTime)
+
+proc CleanExpired*(db: DbConn) {.raises: [].} =
+  try:
+    let stmt = db.stmt("DELETE FROM url WHERE expires < ?")
+    stmt.exec(times.now())
+  except:
+    discard