reapack

commit bba76f9dffba9b0332644d724413fafe23ce10bf
parent 84f56a613e1cdd241d8fcd33765974c531b03cae
Author: cfillion <cfillion@users.noreply.github.com>
Date:   Mon, 18 Jan 2016 14:59:01 -0500

write code for database migrations

Diffstat:
M
src/database.cpp
 | 
20
+++++++++++++++++++-
M
src/database.hpp
 | 
6
++++--
M
src/registry.cpp
 | 
37
++++++++++++++++++++++++++-----------
M
src/registry.hpp
 | 
3
+++
M
test/database.cpp
 | 
8
++++++++

5 files changed, 60 insertions(+), 14 deletions(-)
diff --git a/src/database.cpp b/src/database.cpp
@@ -46,6 +46,19 @@ Database::~Database()
   sqlite3_close(m_db);
 }
 
+int Database::version() const
+{
+  int version = 0;
+
+  Statement stmt("PRAGMA user_version", this);
+  stmt.exec([&] {
+    version = stmt.intColumn(0);
+    return false;
+  });
+
+  return version;
+}
+
 Statement *Database::prepare(const char *sql)
 {
   Statement *stmt = new Statement(sql, this);
@@ -65,7 +78,7 @@ reapack_error Database::lastError() const
   return reapack_error(sqlite3_errmsg(m_db));
 }
 
-Statement::Statement(const char *sql, Database *db)
+Statement::Statement(const char *sql, const Database *db)
   : m_db(db)
 {
   if(sqlite3_prepare_v2(db->m_db, sql, -1, &m_stmt, nullptr) != SQLITE_OK)
@@ -113,6 +126,11 @@ void Statement::exec(const ExecCallback &callback)
   }
 }
 
+int Statement::intColumn(const int index) const
+{
+  return sqlite3_column_int(m_stmt, index);
+}
+
 uint64_t Statement::uint64Column(const int index) const
 {
   return (uint64_t)sqlite3_column_int64(m_stmt, index);
diff --git a/src/database.hpp b/src/database.hpp
@@ -35,6 +35,7 @@ public:
   Database(const std::string &filename = std::string());
   ~Database();
 
+  int version() const;
   Statement *prepare(const char *sql);
   void exec(const char *sql);
 
@@ -56,16 +57,17 @@ public:
   void exec();
   void exec(const ExecCallback &);
 
+  int intColumn(const int index) const;
   uint64_t uint64Column(const int index) const;
   std::string stringColumn(const int index) const;
 
 private:
   friend Database;
 
-  Statement(const char *sql, Database *db);
+  Statement(const char *sql, const Database *db);
   ~Statement();
 
-  Database *m_db;
+  const Database *m_db;
   sqlite3_stmt *m_stmt;
 };
 
diff --git a/src/registry.cpp b/src/registry.cpp
@@ -29,17 +29,7 @@ using namespace std;
 Registry::Registry(const Path &path)
   : m_db(path.join())
 {
-  m_db.exec(
-    "PRAGMA foreign_keys = ON;"
-
-    "CREATE TABLE IF NOT EXISTS entries ("
-    "  remote TEXT NOT NULL,"
-    "  category TEXT NOT NULL,"
-    "  package TEXT NOT NULL,"
-    "  version INTEGER NOT NULL,"
-    "  UNIQUE(remote, category, package)"
-    ");"
-  );
+  migrate();
 
   m_insertEntry = m_db.prepare(
     "INSERT OR REPLACE INTO entries "
@@ -56,6 +46,31 @@ Registry::Registry(const Path &path)
   m_db.exec("BEGIN EXCLUSIVE TRANSACTION");
 }
 
+void Registry::migrate()
+{
+  switch(m_db.version()) {
+  case 0:
+    // new database!
+    m_db.exec(
+      "PRAGMA user_version = 1;"
+
+      "CREATE TABLE entries ("
+      "  remote TEXT NOT NULL,"
+      "  category TEXT NOT NULL,"
+      "  package TEXT NOT NULL,"
+      "  version INTEGER NOT NULL,"
+      "  UNIQUE(remote, category, package)"
+      ");"
+    );
+    break;
+  case 1:
+    // current schema version
+    break;
+  default:
+    throw reapack_error("database was created with a newer version of ReaPack");
+  }
+}
+
 void Registry::push(Version *ver)
 {
   Package *pkg = ver->package();
diff --git a/src/registry.hpp b/src/registry.hpp
@@ -51,6 +51,9 @@ public:
   QueryResult query(Package *) const;
 
 private:
+  int version();
+  void migrate();
+
   Database m_db;
   Statement *m_insertEntry;
   Statement *m_findEntry;
diff --git a/test/database.cpp b/test/database.cpp
@@ -94,3 +94,11 @@ TEST_CASE("bing values and clear", M) {
     REQUIRE(string(e.what()) == "NOT NULL constraint failed: test.value");
   }
 }
+
+TEST_CASE("version", M) {
+  Database db;
+  REQUIRE(db.version() == 0);
+
+  db.exec("PRAGMA user_version = 1");
+  REQUIRE(db.version() == 1);
+}