feat(glib): add Vala VAPI for GADBC

[esodan]

Vala VAPI file is generated for current GADBC 1.0 API version.

It is disable by default, but recommended to be enable when a development package is distributed.

This commit force a 1.0 API versioning, replacing the old one where 0 were used for GIR API version (gir_version), so now shows '1.0' instead of '0.0'.

[github-actions]

⚠️ Please follow the Conventional Commits format in CONTRIBUTING.md for PR titles.

[kou]

Could you also add a simple example like https://github.com/apache/arrow/blob/main/c_glib/example/vala/build.vala ?
Or do you want me to do it?

[kou]

Could you also read the auto-generated comment: #1152 (comment)

[esodan]

⚠️ Please follow the Conventional Commits format in CONTRIBUTING.md for PR titles.

Should be done now.

[esodan]

Could you also add a simple example like https://github.com/apache/arrow/blob/main/c_glib/example/vala/build.vala ? Or do you want me to do it?

I've added a C and Vala example for SQLite

[esodan]

I would like to add an example on how to access a data from a SELECT statement, could you guide me on how can I do that?

I have a problem: GArrow.Statement.execute() returns an out pointer (void*) but it seams to be a ArrowArrayStream which seams doesn't exists in the GLib/API, it is like an interface to be implemented, but no one in the API seems to be used to provide this functionality.

I think is required a GArrowArrayStream as a GInterface to be implemented by a GArrowSimpleStream that can be used to bind an ArrowArrayStream returns from execute().

By adding the above interface should be easy to bind to Vala and simple to use from GLIb/C API I think.

This interface could be defined to contain the methods: get_schema() and get_next(); don't think release() is usable, as it will be a GObject and g_object_unref(), calling release() internally, can be used.

GArrowSimpleStream could be a simple object that can be used to provide a GArrowArrayStream interface, and constructed from an ArrowArrayStream to access the functionality.

Also, this will help others to write C or even, Vala or any other supported GObject Introspection languages, drivers to databases or sources using Arrow format.

[kou]

Sure. We can use garrow_record_batch_reader_import() in Arrow GLib to read data from ArrowArrayStream:

diff --git a/glib/example/meson.build b/glib/example/meson.build
index bc365d72..01932312 100644
--- a/glib/example/meson.build
+++ b/glib/example/meson.build
@@ -18,7 +18,7 @@
 # under the License.
 
 executable('sqlite', 'sqlite.c',
-           dependencies: [adbc_glib],
+           dependencies: [adbc_glib, dependency('arrow-glib')],
            link_language: 'c')
 
 install_data('README.md',
diff --git a/glib/example/sqlite.c b/glib/example/sqlite.c
index 254c8ab5..3d2bd282 100644
--- a/glib/example/sqlite.c
+++ b/glib/example/sqlite.c
@@ -19,6 +19,8 @@
 
 #include <stdlib.h>
 
+#include <arrow-glib/arrow-glib.h>
+
 #include <adbc-glib/adbc-glib.h>
 
 int main(int argc, char** argv) {
@@ -68,6 +70,77 @@ int main(int argc, char** argv) {
     return EXIT_FAILURE;
   }
 
+  GADBCStatement *statement = gadbc_statement_new(conn, &error);
+  if (!statement) {
+    g_print("Error initializing a statement: %s", error->message);
+    g_object_unref(conn);
+    g_object_unref(database);
+    return EXIT_FAILURE;
+  }
+  if (!gadbc_statement_set_sql_query(statement,
+                                     "select sqlite_version() as version",
+                                     &error)) {
+    g_print("Error setting a query: %s", error->message);
+    g_object_unref(statement);
+    g_object_unref(conn);
+    g_object_unref(database);
+    return EXIT_FAILURE;
+  }
+  gpointer c_abi_array_stream;
+  gint64 n_rows_affected;
+  if (!gadbc_statement_execute(statement,
+                               TRUE,
+                               &c_abi_array_stream,
+                               &n_rows_affected,
+                               &error)) {
+    g_print("Error executing a query: %s", error->message);
+    g_error_free(error);
+    g_object_unref(statement);
+    g_object_unref(conn);
+    g_object_unref(database);
+    return EXIT_FAILURE;
+  }
+  GArrowRecordBatchReader *reader =
+    garrow_record_batch_reader_import(c_abi_array_stream, &error);
+  g_free(c_abi_array_stream);
+  if (!reader) {
+    g_print("Error importing a result: %s", error->message);
+    g_error_free(error);
+    g_object_unref(statement);
+    g_object_unref(conn);
+    g_object_unref(database);
+    return EXIT_FAILURE;
+  }
+  GArrowTable *table = garrow_record_batch_reader_read_all(reader, &error);
+  g_object_unref(reader);
+  if (!table) {
+    g_print("Error reading a result: %s", error->message);
+    g_error_free(error);
+    g_object_unref(statement);
+    g_object_unref(conn);
+    g_object_unref(database);
+    return EXIT_FAILURE;
+  }
+  gchar *table_content = garrow_table_to_string(table, &error);
+  g_object_unref(table);
+  if (!table_content) {
+    g_print("Error stringify a result: %s", error->message);
+    g_error_free(error);
+    g_object_unref(statement);
+    g_object_unref(conn);
+    g_object_unref(database);
+    return EXIT_FAILURE;
+  }
+  g_print("Result:\n%s\n", table_content);
+  g_free(table_content);
+  gadbc_statement_release(statement, &error);
+  if (error) {
+    g_print("Error releasing a statement: %s", error->message);
+    g_error_free(error);
+    error = NULL;
+  }
+  g_object_unref(statement);
+
   g_object_unref(conn);
   g_object_unref(database);

[kou]

For Vala:

diff --git a/glib/example/meson.build b/glib/example/meson.build
index bc365d72..76a07079 100644
--- a/glib/example/meson.build
+++ b/glib/example/meson.build
@@ -17,8 +17,10 @@
 # specific language governing permissions and limitations
 # under the License.
 
+arrow_glib = dependency('arrow-glib')
+
 executable('sqlite', 'sqlite.c',
-           dependencies: [adbc_glib],
+           dependencies: [adbc_glib, arrow_glib],
            link_language: 'c')
 
 install_data('README.md',
diff --git a/glib/example/vala/meson.build b/glib/example/vala/meson.build
index f5debcd7..731e0439 100644
--- a/glib/example/vala/meson.build
+++ b/glib/example/vala/meson.build
@@ -25,10 +25,11 @@ if generate_vapi
     ],
     'dependencies': [
       adbc_glib_vapi,
-      dependency('gobject-2.0'),
+      arrow_glib,
     ],
     'vala_args': [
       '--pkg', 'posix',
+      '--vapidir', arrow_glib.get_variable('vapidir'),
     ],
   }
   executable('sqlite', 'sqlite.vala',
diff --git a/glib/example/vala/sqlite.vala b/glib/example/vala/sqlite.vala
index dedb42a3..8d7d2068 100644
--- a/glib/example/vala/sqlite.vala
+++ b/glib/example/vala/sqlite.vala
@@ -29,10 +29,18 @@ int main (string[] args) {
       GLib.message ("Connection to database initialized...");
       try {
         var stm = new GADBC.Statement (conn);
-        string sql = "CREATE TABLE IF NOT EXISTS test (id INTEGER, name TEXT)";
+        string sql = "SELECT sqlite_version() AS version";
         stm.set_sql_query (sql);
-        stm.execute (false, null, null);
-      GLib.message ("Statement executed: %s", sql);
+        void *c_abi_array_stream = null;
+        stm.execute (true, out c_abi_array_stream, null);
+        try {
+            GLib.message ("Statement executed: %s", sql);
+            var reader = GArrow.RecordBatchReader.import (c_abi_array_stream);
+            var table = reader.read_all ();
+            GLib.message ("Executed result: %s", table.to_string ());
+        } finally {
+            GLib.free (c_abi_array_stream);
+        }
       }
       catch (GLib.Error e) {
         GLib.message ("Error executing statement: %s", e.message);

[esodan]

Now all suggestions and examples are in place.

[kou]

+1