@tracepack/evidence-core

Tracepack's core domain model, with zero framework or runtime dependency: TracepackProject, EvidenceItem, TemplateSnapshot, PrivacyFinding, and the pure functions that operate on them. This is the type/logic layer @tracepack/template-engine, @tracepack/evidence-sdk, and Tracepack's own apps all build on -- not a UI, not storage, not PDF handling.

Install

npm install @tracepack/evidence-core

What's in here

• Types: TracepackProject, EvidenceItem, EvidenceCategory, TemplateSnapshot, PrivacyFinding, ChronologyGap, and the supporting field types (Requirement, ReviewStatus, SourceType, PrivacyFindingKind -- all open (string), not closed unions; a template or producer can declare kinds this package has never heard of).
• Pure functions:
  • createProject(...) -- builds a new TracepackProject from a template snapshot.
  • addEvidence(project, item) -- returns a new project with one more evidence item (never mutates the input).
  • getCategoryProgress(project) -- per-category completion state against the template's requirement/minItems.
  • getRequiredSummary(project) -- a project-level "N of M required categories complete" roll-up.
  • getChronologyGaps(project) -- flags a gap between two pieces of dated evidence wider than the template's chronologyRules.maxGapDays, when the template declares one.
  • diffManifests(before, after) -- compares two exported manifest.json files (the tracepack-source-manifest shape @tracepack/export-engine's buildManifest produces) by evidence item id and contentHash. Returns what was added, removed, had its content hash change (an anomaly -- Tracepack's own export guarantee is that an item's original bytes are never mutated), or had an ordinary metadata field (title, category, review status) change. Exposed as tracepack diff-manifest <before.json> <after.json> in @tracepack/cli.
  • looksLikeTracepackManifest(value) -- a lightweight structural check, so a caller gets a clear rejection reason before diffManifests would otherwise fail confusingly on .evidence of an unrelated JSON file.

Every function here is pure -- given the same input, always the same output, no I/O, no mutation of its arguments. That's deliberate: this package has no opinion about where a TracepackProject is stored or rendered.

Usage

import { createProject, addEvidence, getCategoryProgress, type TemplateSnapshot } from "@tracepack/evidence-core";

const template: TemplateSnapshot = {
  id: "example", name: "Example", version: "1.0.0", jurisdiction: "general",
  categories: [{ id: "docs", name: "Documents", requirement: "required", description: "", acceptedTypes: ["pdf"] }],
  exportSections: [],
};

let project = createProject({ title: "My pack", organisation: "", summary: "", desiredResolution: "", template });
project = addEvidence(project, {
  id: "item-1", projectId: project.id, title: "Receipt", categoryId: "docs",
  sourceType: "pdf", originalFileName: "receipt.pdf", importedAt: new Date().toISOString(),
  contentHash: "…", reviewStatus: "needs_review", notes: "", size: 1024, mimeType: "application/pdf",
});

console.log(getCategoryProgress(project));

License

Apache-2.0