Lint rules

This appendix lists all lint rules that bino lint and bino build apply to your report manifests. Lint rules check the content of your documents (semantic/business rules), while schema validation checks the structure.

All lint findings are currently treated as warnings and do not block builds.

Rules

ID	Name	Description
report-artefact-required	Report Artefact Required	At least one ReportArtefact document must be defined.
artefact-layoutpage-required	Artefact LayoutPage Required	Each ReportArtefact must have at least one LayoutPage that matches its constraints and format.
text-content-required	Text Content Required	Text components must have a non-empty spec.value field.
dataset-required	Dataset Required	Table, ChartStructure, and ChartTime components must have a spec.dataset binding.
page-layout-slots-used	Page Layout Slots Used	LayoutPage children count must match the expected slots for its pageLayout.
card-layout-slots-used	Card Layout Slots Used	LayoutCard children count must match the expected slots for its cardLayout.

Rule details

report-artefact-required

Every bino report project needs at least one ReportArtefact document to define what PDF(s) to generate.

Example fix: Add a ReportArtefact manifest to your project:

apiVersion: bino.bi/v1
kind: ReportArtefact
metadata:
  name: my-report
spec:
  title: Monthly Sales Report

artefact-layoutpage-required

Each ReportArtefact must have at least one LayoutPage that:

1. Passes constraints — The page’s metadata.constraints must match the artefact’s context (labels, spec, or mode). The linter checks both build and preview modes; a page is valid if it matches in either mode.
2. Matches format — The page’s spec.pageFormat must match the artefact’s spec.format. Both default to xga if not specified.

Example problem:

# Artefact with format: a4
kind: ReportArtefact
metadata:
  name: print-report
spec:
  format: a4
---
# Page with default format (xga) won't match!
kind: LayoutPage
metadata:
  name: page1
spec:
  children: [...]

Fix: Set spec.pageFormat: a4 on the LayoutPage.

text-content-required

Text components are meant to display content. An empty spec.value produces blank output.

Example problem:

kind: Text
metadata:
  name: header
spec:
  value: "" # Empty!

Fix: Provide meaningful content in spec.value.

dataset-required

Data visualization components (Table, ChartStructure, ChartTime) need a dataset to display. Without spec.dataset, there’s nothing to render.

Example problem:

kind: Table
metadata:
  name: sales-table
spec:
  tableTitle: Sales Overview
  # Missing dataset!

Fix: Add a dataset reference:

spec:
  dataset: sales-data

Or multiple datasets for charts:

spec:
  dataset:
    - revenue
    - costs

page-layout-slots-used

Each LayoutPage must have exactly the number of children that match its pageLayout slot count. This rule is evaluated per artefact, counting only children that:

1. Pass constraints — Children with metadata.constraints must match the artefact’s context.
2. Have valid refs — Children with ref must point to an existing document. Missing refs emit a warning and don’t count as slots.
3. Are renderable — Children must have either a ref or inline spec.

Slot counts for predefined layouts:

Layout	Slots
full	1
split-horizontal	2
split-vertical	2
2x2	4
3x3	9
4x4	16
1-over-2	3
1-over-3	4
2-over-1	3
3-over-1	4

For custom-template, the slot count is the number of distinct named area tokens in pageCustomTemplate:

# 3 slots: a, b, c
pageLayout: custom-template
pageCustomTemplate: |
  "a a"
  "b c"

# 2 slots: aa, bb
pageLayout: custom-template
pageCustomTemplate: |
  "aa aa"
  "bb bb"

Example problem:

kind: LayoutPage
metadata:
  name: dashboard
spec:
  pageLayout: 2x2 # Expects 4 children
  children:
    - kind: Text
      spec: { value: "Hello" }
    - kind: Table
      ref: sales-table
    # Only 2 children, but 2x2 expects 4!

Fix: Add children to fill all slots, or change pageLayout to match actual children count.

card-layout-slots-used

Same as page-layout-slots-used, but for LayoutCard components. Each card’s cardLayout defines how many children it expects.

Example problem:

kind: LayoutCard
metadata:
  name: summary-card
spec:
  cardLayout: split-horizontal # Expects 2 children
  children:
    - kind: Text
      spec: { value: "Only one child" }

Fix: Add a second child or change cardLayout: full.

Adding custom rules

The bino linter is designed for easy rule addition. Each rule has:

• ID: A unique identifier (e.g., naming-lowercase, reference-undefined-dataset).
• Name: A short human-readable name.
• Description: An explanation of what the rule checks.
• Check function: The logic that inspects documents and returns findings.

Rules are registered in internal/report/lint/rules.go.

Suppressing warnings

Currently, lint warnings cannot be suppressed. Future versions may add per-rule or per-file suppression.

See also

• bino lint – CLI command for running lint.
• bino build – build command (runs lint by default).