Using IGWN credentials with HTCondor¶

If your workflow jobs require access to restricted IGWN services, you may need to configure your job to include an authorisation credential.

There are two types of credentials you can use with HTCondor jobs.

Kerberos¶

SciTokens¶

SciTokens are capabiltity tokens that inform services that the bearer of the token should be allowed access to a specific capability (e.g. read) on a specific service. See SciTokens for more details on what SciTokens are and how to use them in general.

For full details on specifying credentials in a job, please see

https://htcondor.readthedocs.io/en/lts/users-manual/submitting-a-job.html#jobs-that-require-credentials

The basic usage valid for the majority of IGWN contexts is as follows:

Using a token in a job¶

To use a SciToken in an HTCondor job, add these commands to your HTCondor submit instructions:

use_oauth_services = <issuer>
<issuer>_oauth_resource = <service-url>
<issuer>_oauth_permissions = <capability>

Where

• <issuer> is the name of the token issuer to use. In all cases for production workflows this should be igwn. For some testing applications, you can use igwn-test.

• <service-url> is the fully-qualified URL of the service to access. This is also referred to as the 'audience' (aud) of the token.

  This is optional, and will default to

  igwn_oauth_resource = ANY
  

• <capability> is the access level that is needed. This is also referred to as the 'scope' (scope) of the token. This can be a space-separated list of multiple scopes.

  This is optional and will default to the default set of scopes for all users (as defined by vault.ligo.org).

For example, to enable queries to the GWDataFind service located at https://datafind.igwn.org you would use:

use_oauth_services = igwn
igwn_oauth_resource = https://datafind.igwn.org
igwn_oauth_permissions = gwdatafind.read

With these instructions, HTCondor would automatically generate a new token for you, and would transfer it to the execute point into the .condor_creds directory. This is typically a subdirectory of the job scratch directory, but the value is stored in the $_CONDOR_CREDS environment variable.

For a single token job like above, the token filename will be igwn.use:

$_CONDOR_CREDS/igwn.use

$_CONDOR_SCRATCH_DIR/.condor_creds/igwn.use

Most IGWN scitoken clients should be able to automatically discover the appropriate token file inside the $_CONDOR_CREDS directory, so you shouldn't actually need to care where the token file exists at the execute point.

To use this token with client tools that do not support discovering tokens inside $_CONDOR_CREDS, you can set the environment variable BEARER_TOKEN_FILE in your condor submit file:

environment = "BEARER_TOKEN_FILE=$$(CondorScratchDir)/.condor_creds/igwn.use"

$ condor_submit science.sub
Submitting job(s)
condor_vault_storer: Credentials exist that do not match the request.
They can be removed by
  condor_store_cred delete-oauth -s igwn
but make sure no other job is using them.
  More details might be available by running
    condor_vault_storer -v "igwn&scopes=gwdatafind.read&audience=https://datafind.igwn.org"

ERROR: (0) invoking /usr/bin/condor_vault_storer

Token handles¶

Tokens may be given a 'handle' to allow HTCondor to distinguish between different sets of permissions and resources.

Handles are specified as a suffix to the <issuer>_oauth_resource and <issuer>_oauth_permissions commands, as follows:

use_oauth_services = igwn
igwn_oauth_resource_gracedb = https://gracedb.ligo.org
igwn_oauth_permissions_gracedb = gracedb.read

In the above example the handle is gracedb.

Tokens with handles are stored using the filename <issuer>_<handle>.use. In the above example, the token will be generated on the access point as

igwn_gracedb.use

and made available on the execute point as

.condor_creds/igwn_gracedb.use

Using handles for tokens enables submitting multiple different jobs with different token capabilities without clashes.

Using handles for tokens also enables submitting a job that requires multiple tokens.

Multiple tokens¶

To use multiple SciTokens in an HTCondor job, specify multiple tokens with unique handles in the same set of submit commands:

use_oauth_services = igwn
igwn_oauth_resource_token1 = <service-url-1>
igwn_oauth_permissions_token1 = <capability-1>
igwn_oauth_resource_token2 = <service-url-2>
igwn_oauth_permissions_token2 = <capability-2>

This will generate multiple token files with the following names

.condor_creds/igwn_token1.use
.condor_creds/igwn_token2.use

For example, to enable queries to GWDataFind at https://datafind.igwn.org and to GraceDB at https://gracedb.ligo.org in the same job:

use_oauth_services = igwn
igwn_oauth_resource_gwdatafind = https://datafind.igwn.org
igwn_oauth_permissions_gwdatafind = gwdatafind.read
igwn_oauth_resource_gracedb = https://gracedb.ligo.org
igwn_oauth_permissions_gracedb = gracedb.read

use_oauth_services = igwn
igwn_oauth_resource = https://datafind.igwn.org https://gracedb.ligo.org
igwn_oauth_permissions = gwdatafind.read gracedb.read

Examples:¶

1. Downloading proprietary IGWN data via OSDF¶

The following HTCondor submit commands can be used to configure a job with the necessary permissions to transfer IGWN proprietary h(t) data from OSDF to a job:

use_oauth_services = igwn
igwn_oauth_permissions = read:/ligo read:/virgo
should_transfer_files = yes
transfer_input_files = igwn+osdf:///igwn/ligo/frames/O4/hoft_C00/H1/H-H1_HOFT_C00-137/H-H1_HOFT_C00-1373577216-4096.gwf

In the above example, the igwn+osdf URL 'scheme' includes the name for the token (igwn in this case), to tell the appropriate HTCondor file transfer plugin to use that access token when attempting to download the data.

2. Reading proprietary IGWN data from CVMFS¶

The following condor submit commands can be used to configure a job with the necessary permissions to read IGWN proprietary h(t) data from CVMFS:

use_oauth_services = igwn
igwn_oauth_permissions = read:/ligo read:/virgo
environment = "BEARER_TOKEN_FILE=$$(CondorScratchDir)/.condor_creds/igwn.use"

X.509¶

X.509 is a credential standard used to encode an identity so that a service can authenticate a request and enable capabilities based on its own records of what users should be allowed to do.

See X.509 for more details on what X.509 is and how to use it in general.

Using an X.509 credential in a job¶

To use an X.509 credential file in an HTCondor job, add one of the following commands to your submit instructions:

use_x509userproxy = true

x509userproxy = /path/to/myproxy.pem

In either case, the credential will be transferred onto the execute machine with your job and its path encoded in the $X509_USER_PROXY environment variable.