pyslk 2.3.0

Python library for interaction with the DKRZ tape archive based on non-public CLIs slk and slk_helpers

pyslk README

This is a python wrapper library for slk and slk_helpers. The slk is the official command line interface of StrongLink (R) by Crystal Onyx, which is the software managing the tape archive at DKRZ (Deutsches Klimarechenzentrum / German Climate Computing Center). slk_helpers are an in-house development of DKRZ which extends slk. This wrapper is compatible with slk versions >= 3.3.76 (>= 3.3.90 recommended) and slk helpers versions >= 1.13.0 (>= 1.13.3 recommended).

If you have any questions, please contact [e-mail] .

Installation

Dependencies

The installation requires the following dependencies

• >= python 3.9
• >= slk 3.3.76 (>= slk 3.3.90 recommended)
• >= slk_helpers 1.13.0 (>= slk_helpers 1.13.3 recommended)
• >= pandas 1.4.0
• psutil
• >= python-dateutil 2.8.2
• >= tenacity 8.0.1

Installatin via pip

The package can be installed via pip:

pip install pyslk

If a specific version is required:

pip install pyslk=2.2.9

Installation with conda/mamba

You can also install pyslk into a conda environment:

mamba create -n slk pip
conda activate slk

download the latest release for your Python version from one of these locations:

• https://gitlab.dkrz.de/hsm-tools/pyslk/-/packages
• https://hsm-tools.gitlab-pages.dkrz.de/pyslk/availability.html#conda-packages

Install the package es follows (example for pyslk 2.2.4):

conda install --use-local  pyslk-2.2.4-py_0.conda`

Usage

All command lines arguments of slk v3.3.91 and slk_helpers v1.13.3 are available as the functions' arguments.

A few basic usage examples:

List files

# load library
> import pyslk
> import os
# list content of a folder
> pyslk.list("/arch/bm0146/k204221/iow")
    permissions    owner   group      filesize       date   time                                    filename
0   -rwxr-xr-x-  k204221  bm0146  1.268945e+06 2020-06-10  08:25          /arch/bm0146/k204221/iow/INDEX.txt
1   -rw-r--r--t  k204221  bm0146  2.094216e+10 2020-06-05  17:36  /arch/bm0146/k204221/iow/iow_data2_001.tar
2   -rw-r--r--t  k204221  bm0146  2.034971e+10 2020-06-05  17:38  /arch/bm0146/k204221/iow/iow_data2_002.tar
3   -rw-r--r--t  k204221  bm0146  2.088344e+10 2020-06-05  17:38  /arch/bm0146/k204221/iow/iow_data2_003.tar
4   -rw-r--r--t  k204221  bm0146  2.071567e+10 2020-06-05  17:40  /arch/bm0146/k204221/iow/iow_data2_004.tar
5   -rw-r--r--t  k204221  bm0146  2.047869e+10 2020-06-05  17:40  /arch/bm0146/k204221/iow/iow_data2_005.tar
6   -rw-r--r--t  k204221  bm0146  8.364491e+09 2020-06-05  17:41  /arch/bm0146/k204221/iow/iow_data2_006.tar
7   -rw-r--r--t  k204221  bm0146  2.007016e+11 2020-06-05  19:37  /arch/bm0146/k204221/iow/iow_data3_001.tar
8   -rw-r--r--t  k204221  bm0146  2.646606e+10 2020-06-05  19:14  /arch/bm0146/k204221/iow/iow_data3_002.tar
9   -rw-r--r--t  k204221  bm0146  4.194304e+06 2020-06-05  19:43  /arch/bm0146/k204221/iow/iow_data4_001.tar
10  -rw-r--r--t  k204221  bm0146  1.128477e+10 2020-06-05  19:46  /arch/bm0146/k204221/iow/iow_data4_002.tar
11  -rw-r--r--t  k204221  bm0146  2.094216e+10 2020-06-10  08:21  /arch/bm0146/k204221/iow/iow_data5_001.tar
12  -rw-r--r--t  k204221  bm0146  2.034971e+10 2020-06-10  08:23  /arch/bm0146/k204221/iow/iow_data5_002.tar
13  -rw-r--r--t  k204221  bm0146  2.088344e+10 2020-06-10  08:23  /arch/bm0146/k204221/iow/iow_data5_003.tar
14  -rw-r--r--t  k204221  bm0146  2.071567e+10 2020-06-10  08:24  /arch/bm0146/k204221/iow/iow_data5_004.tar
15  -rw-r--r--t  k204221  bm0146  2.047869e+10 2020-06-10  08:25  /arch/bm0146/k204221/iow/iow_data5_005.tar
16  -rw-r--r--t  k204221  bm0146  8.364491e+09 2020-06-10  08:25  /arch/bm0146/k204221/iow/iow_data5_006.tar
17  -rw-r--r--t  k204221  bm0146  2.094216e+10 2020-06-05  17:53   /arch/bm0146/k204221/iow/iow_data_001.tar
18  -rw-r--r--t  k204221  bm0146  2.034971e+10 2020-06-05  17:53   /arch/bm0146/k204221/iow/iow_data_002.tar
19  -rw-r--r--t  k204221  bm0146  2.088344e+10 2020-06-05  17:56   /arch/bm0146/k204221/iow/iow_data_003.tar
20  -rw-r--r--t  k204221  bm0146  2.071567e+10 2020-06-05  17:56   /arch/bm0146/k204221/iow/iow_data_004.tar
21  -rw-r--r--t  k204221  bm0146  2.047869e+10 2020-06-05  17:58   /arch/bm0146/k204221/iow/iow_data_005.tar
22  -rw-r-----t  k204221  bm0146  8.364491e+09 2020-06-05  17:57   /arch/bm0146/k204221/iow/iow_data_006.tar

# check if a file exists
> pyslk.resource_exists("/arch/bm0146/k204221/iow/iow_data2_001.tar")
True
# check another non-existing file
> pyslk.resource_exists("/arch/bm0146/k204221/iow/NOT_EXISTS.tar")
False
# get metadata of a file
> pyslk.get_metadata("/arch/bm0146/k204221/iow/INDEX.txt")
{'netcdf.Title': 'ABC DEF GHI'}
# get size
> pyslk.get_resource_size("/arch/bm0146/k204221/iow/INDEX.txt")
1268945
# get checksums
> pyslk.get_checksum("/arch/bm0146/k204221/iow/INDEX.txt")
{'adler32': '412dec3a',
 'sha512': '83644ffc384c70aaf60d29f3303d771e219f3b3f8abdb3a590ac501faf7abbeb371ee4b6b949a1cdc3fa7c44438cd6643f877e8c1ab27d8fe5cc26eb06896d99'}
# is the file stored in the cache? yet!
> pyslk.is_cached("/arch/bm0146/k204221/iow/INDEX.txt")
True
# retrieve file
> pyslk.retrieve("/arch/bm0146/k204221/iow/INDEX.txt", '.', preserve_path=False)
''
> os.path.exists('INDEX.txt')
True

Search

We want to search for files, which are stored in /arch/bm0146/k204221/iow, are larger than 1 kb and smaller than approximately 2 MB.

# load pyslk
import pyslk.core.gen_queries
import pyslk.base.searching
> import pyslk
# generate search query
> search_query = pyslk.gen_search_query(["path=/arch/bm0146/k204221/iow", "resources.size>1024", "resources.size<2000000"])
> search_query
'{"$and":[{"resources.size":{"$gt":1024}},{"resources.size":{"$lt":2000000}},{"path":{"$gte":"/arch/bm0146/k204221/iow","$max_iterations":1}}]}'
# run search
> search_id = pyslk.search(search_query)
> search_id
677761
# list search results
> pyslk.list(search_id)
   permissions    owner   group   filesize       date   time                            filename
0  -rwxr-xr-x-  k204221  bm0146  1268945.0 2020-06-10  08:25  /arch/bm0146/k204221/iow/INDEX.txt

or just

> import pyslk
> pyslk.list(pyslk.search(pyslk.core.gen_queries.gen_search_query(["path=/arch/bm0146/k204221/iow", "resources.size>1024", "resources.size<2000000"])))
   permissions    owner   group   filesize       date   time                            filename
0  -rwxr-xr-x-  k204221  bm0146  1268945.0 2020-06-10  08:25  /arch/bm0146/k204221/iow/INDEX.txt

Split file list per tape for retrieval

split large retrieval request

This should be done in two terminals!

Terminal 1: recall

> import pyslk
> output = pyslk.group_files_by_tape("/arch/bm0146/k204221/iow", recursive=True)
> output
[{'id': -1, 'location': 'cache', 'description': 'files currently stored in the HSM cache', 'barcode': '', 'status': '', 'file_count': 2, 'files': ['/arch/bm0146/k204221/iow/iow_data4_001.tar', '/arch/bm0146/k204221/iow/INDEX.txt'], 'file_ids': [49058705506, 49058705497], 'search_query': '{"$and":[{"path":{"$gte":"/arch/bm0146/k204221/iow"}},{"smart_pool":"slpstor"}]}'}, {'id': 93505, 'location': 'tape', 'description': 'files stored on the tape with the given ID and barcode/label', 'barcode': 'M10211M8', 'status': 'AVAILABLE', 'file_count': 1, 'files': ['/arch/bm0146/k204221/iow/iow_data3_001.tar'], 'file_ids': [49058705504], 'search_query': '{"$and":[{"path":{"$gte":"/arch/bm0146/k204221/iow"}},{"tape_barcode":"M10211M8"}]}'}, {'id': 75696, 'location': 'tape', 'description': 'files stored on the tape with the given ID and barcode/label', 'barcode': 'C25543L6', 'status': 'AVAILABLE', 'file_count': 2, 'files': ['/arch/bm0146/k204221/iow/iow_data_006.tar', '/arch/bm0146/k204221/iow/iow_data2_001.tar'], 'file_ids': [49058705519, 49058705498], 'search_query': '{"$and":[{"path":{"$gte":"/arch/bm0146/k204221/iow"}},{"tape_barcode":"C25543L6"}]}'}, {'id': 75719, 'location': 'tape', 'description': 'files stored on the tape with the given ID and barcode/label', 'barcode': 'C25566L6', 'status': 'AVAILABLE', 'file_count': 2, 'files': ['/arch/bm0146/k204221/iow/iow_data5_006.tar', '/arch/bm0146/k204221/iow/iow_data5_002.tar'], 'file_ids': [49058705513, 49058705509], 'search_query': '{"$and":[{"path":{"$gte":"/arch/bm0146/k204221/iow"}},{"tape_barcode":"C25566L6"}]}'}, {'id': 75718, 'location': 'tape', 'description': 'files stored on the tape with the given ID and barcode/label', 'barcode': 'C25565L6', 'status': 'AVAILABLE', 'file_count': 1, 'files': ['/arch/bm0146/k204221/iow/iow_data5_004.tar'], 'file_ids': [49058705511], 'search_query': '{"$and":[{"path":{"$gte":"/arch/bm0146/k204221/iow"}},{"tape_barcode":"C25565L6"}]}'}, {'id': 75691, 'location': 'tape', 'description': 'files stored on the tape with the given ID and barcode/label', 'barcode': 'C25538L6', 'status': 'AVAILABLE', 'file_count': 5, 'files': ['/arch/bm0146/k204221/iow/iow_data_004.tar', '/arch/bm0146/k204221/iow/iow_data3_002.tar', '/arch/bm0146/k204221/iow/iow_data2_006.tar', '/arch/bm0146/k204221/iow/iow_data2_004.tar', '/arch/bm0146/k204221/iow/iow_data2_003.tar'], 'file_ids': [49058705517, 49058705505, 49058705503, 49058705501, 49058705500], 'search_query': '{"$and":[{"path":{"$gte":"/arch/bm0146/k204221/iow"}},{"tape_barcode":"C25538L6"}]}'}, {'id': 75723, 'location': 'tape', 'description': 'files stored on the tape with the given ID and barcode/label', 'barcode': 'C25570L6', 'status': 'AVAILABLE', 'file_count': 1, 'files': ['/arch/bm0146/k204221/iow/iow_data5_003.tar'], 'file_ids': [49058705510], 'search_query': '{"$and":[{"path":{"$gte":"/arch/bm0146/k204221/iow"}},{"tape_barcode":"C25570L6"}]}'}, {'id': 75690, 'location': 'tape', 'description': 'files stored on the tape with the given ID and barcode/label', 'barcode': 'C25537L6', 'status': 'AVAILABLE', 'file_count': 1, 'files': ['/arch/bm0146/k204221/iow/iow_data_002.tar'], 'file_ids': [49058705515], 'search_query': '{"$and":[{"path":{"$gte":"/arch/bm0146/k204221/iow"}},{"tape_barcode":"C25537L6"}]}'}, {'id': 75722, 'location': 'tape', 'description': 'files stored on the tape with the given ID and barcode/label', 'barcode': 'C25569L6', 'status': 'AVAILABLE', 'file_count': 2, 'files': ['/arch/bm0146/k204221/iow/iow_data5_005.tar', '/arch/bm0146/k204221/iow/iow_data5_001.tar'], 'file_ids': [49058705512, 49058705508], 'search_query': '{"$and":[{"path":{"$gte":"/arch/bm0146/k204221/iow"}},{"tape_barcode":"C25569L6"}]}'}, {'id': 75693, 'location': 'tape', 'description': 'files stored on the tape with the given ID and barcode/label', 'barcode': 'C25540L6', 'status': 'AVAILABLE', 'file_count': 1, 'files': ['/arch/bm0146/k204221/iow/iow_data_005.tar'], 'file_ids': [49058705518], 'search_query': '{"$and":[{"path":{"$gte":"/arch/bm0146/k204221/iow"}},{"tape_barcode":"C25540L6"}]}'}, {'id': 75692, 'location': 'tape', 'description': 'files stored on the tape with the given ID and barcode/label', 'barcode': 'C25539L6', 'status': 'AVAILABLE', 'file_count': 2, 'files': ['/arch/bm0146/k204221/iow/iow_data_003.tar', '/arch/bm0146/k204221/iow/iow_data4_002.tar'], 'file_ids': [49058705516, 49058705507], 'search_query': '{"$and":[{"path":{"$gte":"/arch/bm0146/k204221/iow"}},{"tape_barcode":"C25539L6"}]}'}, {'id': 75695, 'location': 'tape', 'description': 'files stored on the tape with the given ID and barcode/label', 'barcode': 'C25542L6', 'status': 'AVAILABLE', 'file_count': 3, 'files': ['/arch/bm0146/k204221/iow/iow_data_001.tar', '/arch/bm0146/k204221/iow/iow_data2_002.tar', '/arch/bm0146/k204221/iow/iow_data2_005.tar'], 'file_ids': [49058705514, 49058705499, 49058705502], 'search_query': '{"$and":[{"path":{"$gte":"/arch/bm0146/k204221/iow"}},{"tape_barcode":"C25542L6"}]}'}]
> tapeJobMapping: dict = dict()
# iterate files on normal tapes:
> for iFileSet in output:
    if iFileSet["id"] > 0:
        tapeJobMapping[iFileSet["barcode"]] = pyslk.recall_single(iFileSet["file_ids"], resource_ids=True)
    # wait if 4 recalls are running ...
# get split files (files on more than one tape); JSON looks like this:
#  {
#    "id": -1,
#    "location": "tape",
#    "description": "files stored on more than one tape",
#    "barcode": "",
#    "status": "",
#    "file_count": 1,
#    "files": [
#      "/arch/pd1309/forcings/reanalyses/ERA5/year1999/ERA5_1999_03_part2.tar"
#    ],
#    "file_ids": [
#      49083773276
#    ],
#    "search_query": "{\"$and\":[{\"path\":{\"$gte\":\"/arch/pd1309/forcings/reanalyses/ERA5/year1999\",\"$max_depth\":1}},{\"resources.name\":{\"$regex\":\"ERA5_1999_03_part2.tar\"}}]}"
#  }

> for iFileSet in output:
    if iFileSet["id"] == -1 and iFileSet["location"] == "tape":
        for fileId in iFileSet["file_ids"]:
            pyslk.recall_single(fileId, resource_ids=True)
        # wait if 4 recalls are running ...

Terminal 2: retrieval

> import pyslk
> pyslk.retrieve_improved("/arch/bm0146/k204221/iow", destination="/work/ab1234/test", recursive=True, preserve_path=True, dry_run=True)
pyslk.retrieve_improved("/arch/bm0146/k204221/iow", destination=".", recursive=True, preserve_path=True, dry_run=True)
{'FAILED': {'FAILED_NOT_CACHED': ['/arch/bm0146/k204221/iow/iow_data_006.tar', ...]}, 'ENVISAGED': {'ENVISAGED': ['/arch/bm0146/k204221/iow/iow_data4_001.tar', '/arch/bm0146/k204221/iow/INDEX.txt']}, 'FILES': {'/arch/bm0146/k204221/iow/iow_data_006.tar': '/work/ab1234/test/./arch/bm0146/k204221/iow/iow_data_006.tar', ..., '/arch/bm0146/k204221/iow/INDEX.txt': '/work/ab1234/test/./arch/bm0146/k204221/iow/INDEX.txt'}}
# the 'ENVISAGED' files will be retrieved
> pyslk.retrieve_improved("/arch/bm0146/k204221/iow", destination="/work/ab1234/test", recursive=True, preserve_path=True)
# ... retrieval running ...

pyslk in the DKRZ jupyterhub

To make use of pyslk in the jupyterhub, you have to make the slk executable available in the PATH environment variable. You can do this by creating your own kernel.json file, e.g.,

module load slk
python -m ipykernel install --name slk --display-name "hsm kernel" --env PATH $PATH --env JAVA_HOME $JAVA_HOME --user

You need to restart the kernel if you modified/replaced an existing kernel.json. You can find your kernel.json, e.g., in .local/share/jupyter/kernels/your_kernel depending on where you store your kernel files (probably in your $HOME directory).

If you want to use a different version of slk, you have to update the path to your executable.

See also here.

Contributing

Anyone is welcome to contribute to the code. Please check the HTML documentation for details:

• https://hsm-tools.gitlab-pages.dkrz.de/pyslk/development.html

Acknowledgements

Martin Bergemann (DKRZ), Dogus Kaan Bilir (DKRZ), Lars Buntemeyer (GERICS), Carsten Ehbrecht (DKRZ), Andrej Fast (DKRZ), Helge Heuer (DLR), Karsten Peters-von Gehlen (DKRZ), Fabian Wachsmann (DKRZ) and Karl-Hermann Wieners (MPI-M) contributed to this package. They are listed in alphabetical order.