C3X: Offline cloud cost estimation from Terraform

Highlights

Behavior change: estimate <plan.json> now prices the full post-apply fleet

Estimating from plan JSON previously counted only the resources a plan changed. It now walks planned_values and prices every resource that will exist after apply, so PROJECT TOTAL and the --format json payload reflect the whole projected infrastructure, not just the diff.

If you feed plan JSON into a --budget CI gate, the reported total will be higher than before and may change whether the gate passes. Use the new --show-delta flag for the previous change-only view.

New: c3x estimate --show-delta

A diff-style view from plan JSON with + / ~ / - markers, a DELTA line (creates and updates net of deletions), and a rolled-up summary of unchanged resources. Falls back to the standard renderer with a warning when there is no plan context (for example a plain .tf input).

New: optional(type, default) type-constraint defaults

Module variable optional() defaults are now resolved for both root and child modules, matching Terraform's runtime behavior, so catalog pricing expressions see real values instead of nil.

Fixes

• Guard the plan walk against a null child_modules element and the type-constraint walk against a zero-arg object(), both of which could panic the parser on untrusted input.
• Resources scheduled purely for deletion are excluded from PROJECT TOTAL and surface only in the --show-delta view.

Changelog

• feat(plan): estimate the full post-apply fleet from plan JSON (#52)
• feat(estimate): plan delta view and optional() type defaults (#46)

Install

brew install c3xdev/tap/c3x
go install github.com/c3xdev/c3x/cmd/[email protected]
docker pull ghcr.io/c3xdev/c3x:0.2.0