feat(app): load YAML element templates

[pinussilvestrus]

Uses js-yaml to transform YAML files to JSON element templates. If we decide to merge this, we should consider documenting, or keep it as hidden feature for now.

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What's in

This adds the support of loading these files into the Camunda Modeler and handling them as normal .json element templates configuration. Note that this is not needed to define element templates as .yml, one can also use online tools to make the conversion.

Known Issues

• Error logs are shown for the JSON representative as we still do JSON validation. I think that's okay given the fact we do not display the complete data path for each error (cf. Consider displaying dataPath for element templates validation errors bpmn-io/bpmn-js-properties-panel#459)

Additional Context

Editors as VS Code provide JSON Schema validation of .yml files via extensions.

Useful resources

• https://json-schema-everywhere.github.io/yaml

[pinussilvestrus]

Build artifacts

• https://camunda-modeler-on-demand.s3.eu-central-1.amazonaws.com/slack-time-yaml-templates/camunda-modeler-slack-time-yaml-templates-linux-x64.tar.gz
• https://camunda-modeler-on-demand.s3.eu-central-1.amazonaws.com/slack-time-yaml-templates/camunda-modeler-slack-time-yaml-templates-mac.dmg
• https://camunda-modeler-on-demand.s3.eu-central-1.amazonaws.com/slack-time-yaml-templates/camunda-modeler-slack-time-yaml-templates-mac.zip
• https://camunda-modeler-on-demand.s3.eu-central-1.amazonaws.com/slack-time-yaml-templates/camunda-modeler-slack-time-yaml-templates-win-ia32.zip
• https://camunda-modeler-on-demand.s3.eu-central-1.amazonaws.com/slack-time-yaml-templates/camunda-modeler-slack-time-yaml-templates-win-x64.zip

Example YAML Template

• templates.yml.txt

[pinussilvestrus]

After a chat with @christian-konrad I moved this to backlog. We want to have this, but we need to consider the general story behind YAML support from a product perspective (alongside the Web Modeler).

[CLAassistant]

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