Discloud Deployment Validation via Manifest Configuration

Solving Deployment Inconsistency with Schema Validation

Deploying applications to Discloud often leads to runtime failures when resource definitions in the manifest do not align with the target environment's actual capacity or naming conventions. The solution is to implement the Validation Phase via the platform manifest. By enabling this feature, Discloud inserts a pre‑allocation check into the deployment pipeline, rejecting the deployment immediately if the resource schema is incompatible, rather than allowing a failing container to start.

How the Validation Mechanism Works

The validation feature is triggered by a declarative top‑level block in your Discloud manifest. During the early initialization phase of a deployment, the runtime reads this block to activate behavioral flags. If the validation flag is set to true, the system compares your requested resources against a predefined schema before any actual infrastructure is allocated.

To maintain flexibility across development, staging, and production, Discloud uses a substitution variable resolver. This allows you to keep a single base manifest while changing the validation state per namespace using environment variables.

Implementation Example

Below is a sample configuration for a discloud.config file. In this example, we use a substitution variable ${VALIDATE_DEPLOY} to control whether the schema check is active.

[discloud]
APP_ID = my-app-123
MAIN_FILE = index.js

[features]
# Enables the pre‑allocation validation phase
# Value is resolved from the environment variable VALIDATE_DEPLOY
validation_enabled = ${VALIDATE_DEPLOY}

[resources]
memory = 512
cpu = 0.5

Operational Constraints and Common Pitfalls

While validation prevents runtime crashes, it introduces specific constraints that can block deployments if not handled correctly:

• Silent Fallbacks: If the [features] block is misplaced or the key is misspelled, Discloud defaults to false. The deployment will proceed without validation, and you will not receive an error indicating the feature is inactive.
• Naming Mismatches: Schema validation is strict. If your resource names differ between your local environment and the Discloud namespace, the validation phase will reject the deployment. You must use explicit alias mappings in your environment configuration to ensure consistency.
• Pipeline Latency: Enabling validation adds a small overhead to the deployment time as the system must perform the schema check before proceeding to the allocation phase.

Verifying the Configuration

To ensure the feature is active and the substitution variables are resolving correctly, use the following diagnostic steps.

1. Render the Active Config

Run the render command to see how the platform interprets your manifest after variable substitution. This must be run from the root of your project directory.

# Run as a user with project-level permissions
discloud config render

Expected Result: The output should show validation_enabled = true (or false, depending on your environment variable), confirming the block was parsed correctly.

2. Dry‑Run Deployment

Perform a dry‑run to verify the pipeline logic without altering the live state of your application.

# Execute a dry‑run deployment
discloud deploy --dry-run

Check: Review the pipeline logs. You should see a specific entry indicating that the "Resource Compatibility Validation" phase was executed. If the logs skip directly to allocation, the feature is not active.