Public API

comins-capture@0.0.1

Import only from comins-capture. Runtime exports are exactly capture, CaptureError and paperSize. Internal modules and engine types are not public.

capture(target, options?)

capture(target: HTMLElement, options?: CaptureOptions): Promise<CaptureSnapshot>

Option	Default	Contract
signal	None	AbortSignal; cancellation returns ABORTED
timeoutMs	30000	Positive number, at most 2147483647 ms
ready	None	async ({signal}) => {}; await application readiness
resources.network	deny	deny, same-origin, or {origins:['https://assets.example.com']}
resources.credentials	omit	omit or same-origin
resources.resolve	None	async ({resourceRef,kind,url,signal}) => Blob | undefined

Resolve kind is image/font. Undefined applies network policy. See resources for supported content and limits. Capture requires a connected static HTMLElement in a browser; DOM-free package import is allowed. There is no failure/partial-success option.

CaptureSnapshot

Member	Result / ownership
meta	snapshotId, capturedDpr, sourceRect, startedAt/completedAt, complete status, diagnostics
toSvg(options?)	Promise<CaptureOutput<string>>
toCanvas(options?)	Promise<CaptureOutput<HTMLCanvasElement>>
toBlob(options?)	Promise<CaptureOutput<Blob>>; PNG default, JPEG/WebP/SVG selectable
dispose()	Idempotent release and output cancellation

CaptureOutput is {value, meta}. Output meta adds width/height/unit, MIME and contentRect. Methods accept signal/timeoutMs and execute sequentially per snapshot. BUSY rejects overlap; DISPOSED rejects use after release. The caller owns returned Canvases and application-created Blob URLs.

Sizing, fit, alignment, background and format-specific quality are defined in output options. There are no crop, tile or partial APIs.

paperSize(name, options?)

paperSize(name: PaperName, options?: PaperOptions): Size

Pure DOM-free mm-to-pixel calculation. Names are A3/A4/A5/B3/B4/B5. Defaults: standard ISO (or JIS), portrait (or landscape), ppi 300. Invalid inputs throw RangeError. It does not validate the requested size against a browser’s available memory or promise printing quality.

import {paperSize} from 'comins-capture';
paperSize('A4'); // {width:2480, height:3508}
paperSize('B4', {standard:'JIS', ppi:254}); // {width:2570, height:3640}

CaptureError and types

CaptureError exposes code and prepare/capture/output stage. The complete code list and actions are in lifecycle and errors.

Public types: CaptureTarget, CaptureOptions, CaptureSnapshot, SnapshotMeta, OutputMeta, CaptureOutput, RasterOptions, SvgOptions, BlobOptions, RasterSize, SvgSize, Margins, ResourceOptions, ResourceKind, Size, Rect, PaperName, PaperOptions, NetworkPolicy, Diagnostic, CaptureErrorCode and CaptureStage.

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Runnable example · Source guide for this version