Client-side packages

Introduction

Application built with python-ndn can make use of the client packages provided.

There are four parts:

  1. PutfileClient: insert files into the repo.

  2. GetfileClient: get files from the repo.

  3. DeleteClient: detele data packets from the repo.

  4. CommandChecker: check process status from the repo.

The example programs in examples/ illustrate how to use these packages.

Note that the type Union[Iterable[Union[bytes, bytearray, memoryview, str]], str, bytes, bytearray, memoryview] in the documentation is equivalent to the ndn.name.NonStrictName type.

Reference

class ndn_python_repo.clients.putfile.PutfileClient(app, prefix, repo_name)

A client to insert files into the repo.

Parameters

  • app (NDNApp) – NDNApp.

  • prefix (Union[Iterable[Union[bytes, bytearray, memoryview, str]], str, bytes, bytearray, memoryview]) – NonStrictName. The name of this client

  • repo_name (Union[Iterable[Union[bytes, bytearray, memoryview, str]], str, bytes, bytearray, memoryview]) – NonStrictName. Routable name to remote repo.

async insert_file(file_path, name_at_repo, segment_size, freshness_period, cpu_count, forwarding_hint=None, register_prefix=None, check_prefix=None)

Insert a file to remote repo.

Parameters

  • file_path (str) – Local FS path to file to insert.

  • name_at_repo (Union[Iterable[Union[bytes, bytearray, memoryview, str]], str, bytes, bytearray, memoryview]) – NonStrictName. Name used to store file at repo.

  • segment_size (int) – Max size of data packets.

  • freshness_period (int) – Freshness of data packets.

  • cpu_count (int) – Cores used for converting file to TLV format.

  • forwarding_hint (Union[Iterable[Union[bytes, bytearray, memoryview, str]], str, bytes, bytearray, memoryview, None]) – NonStrictName. The forwarding hint the repo uses when fetching data.

  • register_prefix (Union[Iterable[Union[bytes, bytearray, memoryview, str]], str, bytes, bytearray, memoryview, None]) – NonStrictName. If repo is configured with register_root=False, it registers register_prefix after receiving the insertion command.

  • check_prefix (Union[Iterable[Union[bytes, bytearray, memoryview, str]], str, bytes, bytearray, memoryview, None]) – NonStrictName. The repo will publish process check messages under <check_prefix>/check. It is necessary to specify this value in the param, instead of using a predefined prefix, to make sure the subscriber can register this prefix under the NDN prefix registration security model. If not specified, default value is the client prefix.

Return type

int

Returns

Number of packets inserted.

class ndn_python_repo.clients.getfile.GetfileClient(app, repo_name)

This client fetches a file from the repo, and save it to working directory.

A client to retrieve files from the remote repo.

Parameters

  • app (NDNApp) – NDNApp.

  • repo_name – NonStrictName. Routable name to remote repo.

async fetch_file(name_at_repo, local_filename=None, overwrite=False)

Fetch a file from remote repo, and write to the current working directory.

Parameters

  • name_at_repo (Union[Iterable[Union[bytes, bytearray, memoryview, str]], str, bytes, bytearray, memoryview]) – NonStrictName. The name with which this file is stored in the repo.

  • local_filename (Optional[str]) – str. The filename of the retrieved file on the local file system.

  • overwrite – If true, existing files are replaced.

class ndn_python_repo.clients.delete.DeleteClient(app, prefix, repo_name)

This client deletes data packets from the remote repo.

Parameters

  • app (NDNApp) – NDNApp.

  • repo_name (Union[Iterable[Union[bytes, bytearray, memoryview, str]], str, bytes, bytearray, memoryview]) – NonStrictName. Routable name to remote repo.

async delete_file(prefix, start_block_id=0, end_block_id=None, register_prefix=None, check_prefix=None)

Delete from repo packets between “<name_at_repo>/<start_block_id>” and “<name_at_repo>/<end_block_id>” inclusively.

Parameters

  • prefix (Union[Iterable[Union[bytes, bytearray, memoryview, str]], str, bytes, bytearray, memoryview]) – NonStrictName. The name of the file stored in the remote repo.

  • start_block_id (int) – int. Default value is 0.

  • end_block_id (Optional[int]) – int. If not specified, repo will attempt to delete all data packets with segment number starting from start_block_id continously.

  • register_prefix (Union[Iterable[Union[bytes, bytearray, memoryview, str]], str, bytes, bytearray, memoryview, None]) – If repo is configured with register_root=False, it unregisters register_prefix after receiving the deletion command.

  • check_prefix (Union[Iterable[Union[bytes, bytearray, memoryview, str]], str, bytes, bytearray, memoryview, None]) – NonStrictName. The repo will publish process check messages under <check_prefix>/check. It is necessary to specify this value in the param, instead of using a predefined prefix, to make sure the subscriber can register this prefix under the NDN prefix registration security model. If not specified, default value is the client prefix.

Return type

int

Returns

Number of deleted packets.

class ndn_python_repo.clients.command_checker.CommandChecker(app)

This client sends check interests to the repo.

Parameters

app (NDNApp) – NDNApp.

async check_delete(repo_name, request_no)

Check the status of a delete process.

Parameters

  • repo_name – NonStrictName. The name of the remote repo.

  • request_no (bytes) – bytes. The request id of the process to check.

Return type

RepoCommandRes

Returns

The response from the repo.

async check_insert(repo_name, request_no)

Check the status of an insert process.

Parameters

  • repo_name (Union[Iterable[Union[bytes, bytearray, memoryview, str]], str, bytes, bytearray, memoryview]) – NonStrictName. The name of the remote repo.

  • request_no (bytes) – bytes. The request id of the process to check.

Return type

RepoCommandRes

Returns

The response from the repo.