implement new command for using fast latch-persistence copies

src/latch_cli/main.py

@@ -812,6 +812,23 @@ def cp(
         chunk_size_mib=chunk_size_mib,
     )
 
+@main.command("cp-fast")
+@click.argument("src", shell_complete=cp_complete, nargs=-1)
+@click.argument("dest", shell_complete=cp_complete, nargs=1)
+@requires_login
+def cp_fast(
+    src: List[str],
+    dest: str,
+):
+    """
+    Fast copy of files between Latch Data and local, or between two Latch Data locations.
+    """
+    crash_handler.message = f"Unable to copy {src} to {dest}"
+    crash_handler.pkg_root = str(Path.cwd())
+
+    from latch_cli.services.cp.main import cp_fast
+
+    cp_fast(src, dest)
 
 @main.command("mv")
 @click.argument("src", shell_complete=remote_complete, nargs=1)

src/latch_cli/services/cp/main.py

@@ -8,6 +8,7 @@
 from latch.ldata._transfer.progress import Progress
 from latch.ldata._transfer.remote_copy import remote_copy as _remote_copy
 from latch.ldata._transfer.upload import upload as _upload
+from latch.ldata.path import LPath
 from latch.ldata.type import LatchPathError
 from latch_cli.services.cp.glob import expand_pattern
 from latch_cli.utils import human_readable_time, with_si_suffix
@@ -104,3 +105,34 @@ def cp(
         except Exception as e:
             click.secho(str(e), fg="red")
             raise click.exceptions.Exit(1) from e
+
+def cp_fast(
+    srcs: List[str],
+    dest: str,
+):
+    dest_remote = is_remote_path(dest)
+
+    for src in srcs:
+        src_remote = is_remote_path(src)
+
+        try:
+            if src_remote and not dest_remote:
+                LPath(src).download(Path(dest))
+            elif not src_remote and dest_remote:
+                LPath(dest).upload_from(Path(src))
+            elif src_remote and dest_remote:
+                LPath(src).copy_to(LPath(dest))
+            else:
+                raise ValueError(
+                    dedent(f"""
+                    `latch cp-fast` cannot be used for purely local file copying.
+
+                    Please ensure at least one of your arguments is a remote path (beginning with `latch://`)
+                    """).strip("\n"),
+                )
+        except LatchPathError as e:
+            click.secho(get_path_error(e.remote_path, e.message, e.acc_id), fg="red")
+            raise click.exceptions.Exit(1) from e
+        except Exception as e:
+            click.secho(str(e), fg="red")
+            raise click.exceptions.Exit(1) from e