[feat] Add support of Secondary Instances (#29)

* Adding `OpenAsSecondary` support

* Bump up version

* Bump up version to 0.5.0

---------

Co-authored-by: Albert Torosyan <torosyanalbert@gmail.com>

setup.py

@@ -92,7 +92,7 @@
 
 setup(
     name="aimrocks",
-    version='0.4.0',
+    version='0.5.0',
     description='RocksDB wrapper implemented in Cython.',
     setup_requires=['setuptools>=25', 'Cython>=3.0.0a9'],
     packages=find_packages('./src'),

src/aimrocks/db.pxd

@@ -157,6 +157,8 @@ cdef extern from "rocksdb/db.h" namespace "rocksdb":
         Status DisableFileDeletions() nogil except+
         Status EnableFileDeletions() nogil except+
 
+        Status TryCatchUpWithPrimary() nogil except+
+
         # TODO: Status GetSortedWalFiles(VectorLogPtr& files)
         # TODO: SequenceNumber GetLatestSequenceNumber()
         # TODO: Status GetUpdatesSince(
@@ -194,6 +196,20 @@ cdef extern from "rocksdb/db.h" namespace "rocksdb":
         DB**,
         cpp_bool) nogil except+
 
+    cdef Status DB_OpenAsSecondary "rocksdb::DB::OpenAsSecondary"(
+        const options.Options&,
+        const string&,
+        const string&,
+        DB**) nogil except+
+
+    cdef Status DB_OpenAsSecondary_ColumnFamilies "rocksdb::DB::OpenAsSecondary"(
+        const options.Options&,
+        const string&,
+        const string&,
+        const vector[ColumnFamilyDescriptor]&,
+        vector[ColumnFamilyHandle*]*,
+        DB**) nogil except+
+
     cdef Status RepairDB(const string& dbname, const options.Options&)
 
     cdef Status ListColumnFamilies "rocksdb::DB::ListColumnFamilies" (

src/aimrocks/lib_rocksdb.pxd

@@ -625,6 +625,7 @@ cdef class DB(IDB):
     cpdef itersitems(self, column_families)
     cpdef snapshot(self)
     cpdef get_property(self, prop, ColumnFamilyHandle column_family = *)
+    cpdef try_catch_up_with_primary(self)
     cpdef get_live_files_metadata(self)
     cpdef void compact_range(
         self,

src/aimrocks/lib_rocksdb.pyx

@@ -1618,9 +1618,17 @@ cdef class DB(IDB):
     # cdef list cf_handles
     # cdef list cf_options
 
-    def __cinit__(self, db_name, Options opts, dict column_families=None, read_only=False):
+    def __cinit__(
+        self,
+        db_name,
+        Options opts,
+        dict column_families=None,
+        read_only=False,
+        secondary_path=None,
+    ):
         cdef Status st
         cdef string db_path
+        cdef string secondary_path_c
         cdef vector[db.ColumnFamilyDescriptor] column_family_descriptors
         cdef vector[db.ColumnFamilyHandle*] column_family_handles
         cdef bytes default_cf_name = db.kDefaultColumnFamilyName
@@ -1666,7 +1674,19 @@ cdef class DB(IDB):
                     )
                 )
                 self.cf_options.append(cf_options)
-        if read_only:
+
+        if secondary_path is not None:
+            assert read_only
+            secondary_path_c = path_to_string(secondary_path)
+            with nogil:
+                st = db.DB_OpenAsSecondary_ColumnFamilies(
+                    deref(opts.opts),
+                    db_path,
+                    secondary_path_c,
+                    column_family_descriptors,
+                    &column_family_handles,
+                    &self.db)
+        elif read_only:
             with nogil:
                 st = db.DB_OpenForReadOnly_ColumnFamilies(
                     deref(opts.opts),
@@ -2073,6 +2093,9 @@ cdef class DB(IDB):
         else:
             return None
 
+    cpdef try_catch_up_with_primary(self):
+        self.db.TryCatchUpWithPrimary()
+
     cpdef get_live_files_metadata(self):
         cdef vector[db.LiveFileMetaData] metadata