Скачать или смотреть Understanding the YAML to JSON Conversion Error: Failed to Read Input Object

Discover the causes of the `failed to read input object` error in YAML, how indentation issues play a role, and find solutions to automatically align your YAML files for seamless Jenkins builds.
---
This video is based on the question https://stackoverflow.com/q/63360606/ asked by the user 'GKr297' ( https://stackoverflow.com/u/13628029/ ) and on the answer https://stackoverflow.com/a/63361113/ provided by the user 'flyx' ( https://stackoverflow.com/u/347964/ ) at 'Stack Overflow' website. Thanks to these great users and Stackexchange community for their contributions.

Visit these links for original content and any more details, such as alternate solutions, latest updates/developments on topic, comments, revision history etc. For example, the original title of the Question was: error: failed to read input object (not a Template?): error converting YAML to JSON: yaml: mapping values are not allowed in this context

Also, Content (except music) licensed under CC BY-SA https://meta.stackexchange.com/help/l...
The original Question post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license, and the original Answer post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license.

If anything seems off to you, please feel free to write me at vlogize [AT] gmail [DOT] com.
---
Understanding the YAML to JSON Conversion Error: Failed to Read Input Object

When working with YAML files, especially in contexts like Jenkins builds, you may encounter the frustrating error: failed to read input object (not a Template?): error converting YAML to JSON: yaml: mapping values are not allowed in this context. This error often arises due to improper indentation in your YAML file, leading to a cascade of issues that can halt your CI/CD processes. In this guide, we'll dive into the details of what causes this error and how you can resolve it effectively.

What Causes the Error?

The error is typically triggered when the YAML parser encounters incorrectly structured data—usually linked to indentation. YAML files are sensitive to whitespace, similar to Python. Here's an example of problematic YAML:

[[See Video to Reveal this Text or Code Snippet]]

In the snippet above, the line valueFrom: is indented more than its parent key name:, which leads to confusion during parsing. The YAML interpreter interprets this as an invalid input, throwing up the error mentioned above.

Key Issues to Note:

Indentation Matters: YAML uses spaces for indentation, and incorrect spaces can disrupt the flow of data.

Scalar Values: When a new key-value mapping starts with a :, it signals the end of a previous mapping, which can confuse the indentation structure.

Solution: Correcting Indentation

To rectify the error, you need to correct the indentation issues in your YAML file. Here are two potential corrected formats based on the provided snippet:

Option 1: Corrected Indentation

[[See Video to Reveal this Text or Code Snippet]]

Option 2: Alternative Structure

If your intent was to attach valueFrom as a subkey of name, it could look like this:

[[See Video to Reveal this Text or Code Snippet]]

This option indicates that the valueFrom key should have a hierarchical relationship with name, but ensure it complies with your overall data structure.

Auto Aligning YAML Files

If you're struggling with multiple YAML files and consistent aligning challenges, you may wonder: Is there a way to auto-align YAML files? Unfortunately, there isn't a foolproof solution that can guess the intended semantics of badly formatted YAML. While theoretical approaches exist (like training machine learning models on YAML syntax issues), practical tools that reliably correct indentation do not currently exist.

Alternative Solutions:

Text Editors: Use advanced text editors like VSCode or Sublime Text, which have features or plugins to format YAML automatically.

Linter Tools: Consider using YAML linting tools available online, which can help identify indentation issues.

Manual Checks: Regularly review and manually adjust your YAML files for consistent indentation practices.

Conclusion

The failed to read input object error due to YAML indentation can be a daunting issue that disrupts workflows, especially in automated environments like Jenkins. By correctly aligning your YAML files and understanding the significance of indentation, you can prevent these errors and ensure smoother execution of your builds.

Feel free to save this guide for future reference and improve your YAML prowess today!