Use require("extract") to find JSON, YAML, and similar structured-data candidates embedded in larger text.

The module returns candidates, not fully trusted parsed values. A candidate preserves source spans, wrapper metadata, format guesses, confidence, and diagnostics so downstream code can decide what to parse or repair.

Loading

const extract = require("extract");

Functions

options()

Returns a Go-backed extraction options builder. Use this to control accepted formats, tags, confidence thresholds, and validation behavior as the API grows.

const options = extract.options().Build();

markdownCodeBlocks(input, options?)

Finds Markdown fenced code blocks that look like structured data.

const candidates = extract.markdownCodeBlocks("~~~json\n{\"ok\": true}\n~~~");

xmlTagged(input, options?)

Finds simple XML-like same-name wrappers such as <json>...</json> and <yaml>...</yaml>.

This is intentionally XML-like extraction, not a full XML parser.

frontmatter(input, options?)

Finds YAML frontmatter at the start of a document.

rawStructured(input, options?)

Finds whole-string raw JSON or YAML candidates.

all(input, options?)

Runs all extractors and returns candidates sorted by source order.

Overlapping candidates are preserved in the current API so scripts can inspect the evidence and choose a policy.

validate(candidate, options?)

Validates and sanitizes one candidate by delegating JSON/YAML repair to the sanitize semantics.

const candidate = extract.all(input)[0];
const result = extract.validate(candidate);
console.log(result.Valid, result.Sanitized);

Candidate fields

Common ExtractionCandidate fields include:

• Kind — wrapper kind such as markdownCodeBlock, xmlTagged, frontmatter, or raw.
• Format — guessed data format, commonly json or yaml.
• Text — payload text intended for parsing.
• Raw — full raw wrapper text.
• StartByte, EndByte, StartRow, StartColumn, EndRow, EndColumn — source span for the raw candidate.
• PayloadStartByte, PayloadEndByte, PayloadStartRow, PayloadStartColumn, PayloadEndRow, PayloadEndColumn — source span for the payload.
• Fence, TagName, Info, Language — wrapper metadata when available.
• Confidence — heuristic confidence score.
• Diagnostics — extraction-time notes.

Validation result fields

Validation results expose PascalCase fields such as Valid, Format, Sanitized, Issues, and Fixes.