thamos 0.8.3

A CLI tool and library for interacting with Thoth

A CLI tool and library for communicating with Thoth backend.

Using Thamos as a CLI tool

Thamos is released on PyPI. See installation instructions bellow to setup Thoth/Thamos for your repository:

# Install Thamos CLI tool:
$ pip3 install thamos  # keep in mind: requires Python 3.6+!!
# Go to repository that should be managed by Thoth which already has Pipfile present:
$ cd ~/git/repo/
# Setup Thamos configuration:
$ thamos config
# Ask Thoth for software stack recommendations:
$ thamos advise
# Retrieve logs of the last analysis:
$ thamos log

As Thamos notes analysis ids for better UX of thamos log, it’s recommended to add .thoth_last_analysis_id file to .gitignore.

Adjusting configuration based on environment variables

You can adjust content of configuration file each time Thamos CLI or Thamos library loads it by expanding entries with environment variables. This can be handy if you would like to parameterize some of the options at runtime (e.g. in deployment).

This behaviour is (due to security reasons) explicitly turned off by default. However you can turn it on by setting THAMOS_CONFIG_EXPAND_ENV environment variable to 1 (0 explicitly turns this behaviour off, default value):

THOTH_HOST=test.thoth-station.ninja THAMOS_CONFIG_EXPAND_ENV=1 thamos advise
2019-03-13 11:22:59,562 [18639] INFO     thamos.config: Expanding configuration file based on environment variables

Entries which should be expanded have environment variables in curly braces like the following example:

host: {THOTH_HOST}

Note the expansion is done by replacing these values directly with values of environment variable, this means types need to be taken into account (environment variable with value "true" is put into configuration file as true).

Using custom configuration file template

You can use your own custom configuration file as a template. This is especially useful if you want to have some configuration entries constant and let expand only some of the configuration options. In other words, you can parametrize configuration file.

An example of configuration file template can be:

host: {THOTH_SERVICE_HOST}
tls_verify: true
requirements_format: pipenv

runtime_environments:
  - name: '{os_name}:{os_version}'
    operating_system:
      name: {os_name}
      version: '{os_version}'
    hardware:
      cpu_family: {cpu_family}
      cpu_model: {cpu_model}
    python_version: '{python_version}'
    cuda_version: {cuda_version}
    recommendation_type: stable
    limit_latest_versions: null

Then, you need to supply this configuration file to the following command:

thamos config --template template.yaml

Listing of automatically expanded configuration options which are supplied the config sub-command (these options are optional and will be expanded based on HW or SW discovery):

Configuration option	Explanation	Example
os_name	name of operating system	fedora
os_version	version of operating system	30
cpu_family	CPU family identifier	6
cpu_model	CPU model identifier	94
python_version	Python version (major.minor)	3.6
cuda_version	CUDA version (major.minor)	9.0

These configuration options are optional and can be mixed with adjustment based on environment variables (see THOTH_SERVICE_HOST example above). Note the environment variables are not expanded on thamos config call but rather on other sub-commands issued (e.g. thamos advise or others).

The output format coming out of recommendations can be compatible with Pipenv, raw pip or similar to the one provided by pip-tools (actually same as for pip as these formats are interchangeable). The format is configured using requirements_format configuration option, available options are:

• requirements_format: pipenv for Pipenv compatible output

• requirements_format: pip or requirements_format: pip-tools for pip or pip-tools compatible output

Using Thoth and thamos in OpenShift’s s2i

Using configuration templates is especially useful for OpenShift builds where you can specify your template in an s2i repository (omit Pipfile.lock to enable call to thamos advise as shown in this repository).

Then, you need to provide following environment variables:

• THAMOS_CONFIG_TEMPLATE - holds path to template - use /tmp/src prefix to point to root of s2i repository (e.g. /tmp/src/template.yaml if template.yaml is the configuration template and is stored in root of your Git repository).

• THAMOS_NO_INTERACTIVE - set to 1 if you don’t want to omit interactive thamos (suitable for automated s2i builds happening in the cluster).

• THAMOS_NO_PROGRESSBAR - set to 1 to disable progressbar while waiting for response from Thoth backend - it can cause annoying too verbose output printed to OpenShift console during the build.

• THAMOS_CONFIG_EXPAND_ENV - set to 1 to enable expansion based on environment variables when generating .thoth.yaml file - this needs to be explicitly turned on due to possible security implications.

• THAMOS_FORCE - set to 1 not use cached results, always force analysis on Thoth’s side (note this option can be ignored by a Thoth operator based on deployment configuration).

• THAMOS_VERBOSE - set to 1 to run thamos in verbose mode to show what’s going on (verbosity on client side).

• THAMOS_DEBUG - set to 1 to run analyzes (adviser, provenance checker, …) on Thoth’s backend side in debug mode, you can obtain logs by running thamos logs or directly on Thoth’s user API; the analysis id gets printed into the console during the build process in OpenShift (verbosity on server side).

See OpenShift s2i documentation on how to pin build to a specific node in the cluster. This is needed if you would like to perform automatic hardware discovery to get optimized stacks on your hardware.

Using Thamos as a library

from thamos.lib import image_analysis
from thamos.config import config

# Set global context.
# Host to Thoth's User API. API discovery will be done
# transparently and the most appropriate API version will be used.
config.explicit_host = "thoth-user-api.redhat.com"
# TLS verification when communicating with Thoth API.
config.tls_verify = True

image_analysis(
  image="registry.redhat.com/fedora:29",
  registry_user="fridex",
  registry_password="secret!",
  # TLS verification when communicating with registry.
  verify_tls=True,
  nowait=False
)

Disabling TLS related warnings

If you communicate with Thoth’s user API without TLS (you have set the tls_verify configuration option to false in the .thoth.yaml file), Thamos CLI and Thamos library issue a warning each time there is done communication with the API server. To suppress this warning, set the THAMOS_DISABLE_TLS_WARNING environment variable to a non-zero value:

$ export THAMOS_DISABLE_TLS_WARNING=1
$ thamos advise

Autogenerated client from OpenAPI

Most parts of Thamos consist of automatic generated code. You can update Thamos by running the following command:

$ ./swagger-codegen.sh

The command above will download and run automatic code generation tool against the most recent OpenAPI specification of User API. Results of the tool are automatically placed into this repository in thamos/swagger_client/ and Documentation/. They consist of automatically generated code as well as documentation on how to use the code. Thamos itself provides routines built on top of this automated generated code to simplify usage in thamos/lib.