Ankus.Examples.CustomLibraryName

Custom library name example

This ports pgrx's custom_libname example. Its Cargo package is custom_libname, but its [lib] name is other_name, so the shared library is other_name and the control file sets module_pathname = 'other_name'.

In Ankus, AnkusLibraryName names the native library without changing the assembly or the SQL extension:

<AnkusLibraryName>other_name</AnkusLibraryName>
<AnkusExtensionName>ankus_custom_libname</AnkusExtensionName>

Publishing produces other_name.so (other_name.dll on Windows, other_name.dylib on macOS with PostgreSQL 16 and later) and a control file whose module_pathname is that filename:

CREATE EXTENSION ankus_custom_libname;

SELECT hello_custom_libname();                       -- Hello, custom_libname
SELECT probin FROM pg_proc
WHERE oid = 'hello_custom_libname()'::regprocedure;  -- other_name.so

-- PostgreSQL 18 and later
SELECT module_name, file_name FROM pg_get_loaded_modules();
-- Ankus.Examples.CustomLibraryName | other_name.so

pgrx mapping

pgrx	Ankus
Cargo [package] name = "custom_libname"	The project, Ankus.Examples.CustomLibraryName.csproj, and its assembly name
Cargo [lib] name = "other_name"	<AnkusLibraryName>other_name</AnkusLibraryName>
other_name.control with module_pathname = 'other_name'	Generated ankus_custom_libname.control with module_pathname = 'other_name.so'
pg_module_magic!(name, version), which reports the package name	The generated module identity, which reports the assembly name and version
#[pg_extern] fn hello_custom_libname()	[PgFunction] HelloCustomLibname()

Without AnkusLibraryName, the library is named after TargetName, which defaults to AssemblyName. Changing AssemblyName also renames the library, but it changes the assembly's identity too: its module name, default extension name and generated export names. AnkusLibraryName changes only the file, and names such as other_name do not conflict with .NET assembly naming analyzers.

Deliberate differences

• cargo-pgrx names the installed library after the control file (other_name), so pgrx's library and extension names are the same. Ankus names the extension with AnkusExtensionName and the library separately; this sample uses ankus_custom_libname to show that they are independent.
• pgrx writes module_pathname without a suffix. Ankus generates the exact filename, including the suffix PostgreSQL's loader expects on that platform.
• pgrx's #[pg_test] checks the greeting. The Ankus integration test also checks the published filenames, the control file, the embedded schema, the function's probin and, on PostgreSQL 18 and later, the loaded module.

See build settings and the versioned custom library name sample.