// Copyright 2018-2024 the Deno authors. All rights reserved. MIT license. // deno-lint-ignore-file /* * @module mod * @description * This module provides a `display()` function for the Jupyter Deno Kernel, similar to IPython's display. * It can be used to asynchronously display objects in Jupyter frontends. There are also tagged template functions * for quickly creating HTML, Markdown, and SVG views. * * @example * Displaying objects asynchronously in Jupyter frontends. * ```typescript * import { display, html, md } from "https://deno.land/x/deno_jupyter/mod.ts"; * * await display(html`

Hello, world!

`); * await display(md`# Notebooks in TypeScript via Deno ![Deno logo](https://github.com/denoland.png?size=32) * * * TypeScript ${Deno.version.typescript} * * V8 ${Deno.version.v8} * * Deno ${Deno.version.deno} * * Interactive compute with Jupyter _built into Deno_! * `); * ``` * * @example * Emitting raw MIME bundles. * ```typescript * import { display } from "https://deno.land/x/deno_jupyter/mod.ts"; * * await display({ * "text/plain": "Hello, world!", * "text/html": "

Hello, world!

", * "text/markdown": "# Hello, world!", * }, { raw: true }); * ``` */ import { core, internals } from "ext:core/mod.js"; const $display = Symbol.for("Jupyter.display"); /** Escape copied from https://deno.land/std@0.192.0/html/entities.ts */ const rawToEntityEntries = [ ["&", "&"], ["<", "<"], [">", ">"], ['"', """], ["'", "'"], ]; const rawToEntity = new Map(rawToEntityEntries); const rawRe = new RegExp(`[${[...rawToEntity.keys()].join("")}]`, "g"); function escapeHTML(str) { return str.replaceAll( rawRe, (m) => rawToEntity.has(m) ? rawToEntity.get(m) : m, ); } /** Duck typing our way to common visualization and tabular libraries */ /** Vegalite */ function isVegaLike(obj) { return obj !== null && typeof obj === "object" && "toSpec" in obj; } function extractVega(obj) { const spec = obj.toSpec(); if (!("$schema" in spec)) { return null; } if (typeof spec !== "object") { return null; } let mediaType = "application/vnd.vega.v5+json"; if (spec.$schema === "https://vega.github.io/schema/vega-lite/v4.json") { mediaType = "application/vnd.vegalite.v4+json"; } else if ( spec.$schema === "https://vega.github.io/schema/vega-lite/v5.json" ) { mediaType = "application/vnd.vegalite.v5+json"; } return { [mediaType]: spec, }; } /** Polars */ function isDataFrameLike(obj) { const isObject = obj !== null && typeof obj === "object"; if (!isObject) { return false; } const df = obj; return df.schema !== void 0 && typeof df.schema === "object" && df.head !== void 0 && typeof df.head === "function" && df.toRecords !== void 0 && typeof df.toRecords === "function"; } /** * Map Polars DataType to JSON Schema data types. * @param dataType - The Polars DataType. * @returns The corresponding JSON Schema data type. */ function mapPolarsTypeToJSONSchema(colType) { const typeMapping = { Null: "null", Bool: "boolean", Int8: "integer", Int16: "integer", Int32: "integer", Int64: "integer", UInt8: "integer", UInt16: "integer", UInt32: "integer", UInt64: "integer", Float32: "number", Float64: "number", Date: "string", Datetime: "string", Utf8: "string", Categorical: "string", List: "array", Struct: "object", }; // These colTypes are weird. When you console.dir or console.log them // they show a `DataType` field, however you can't access it directly until you // convert it to JSON const dataType = colType.toJSON()["DataType"]; return typeMapping[dataType] || "string"; } function extractDataFrame(df) { const fields = []; const schema = { fields, }; let data = []; // Convert DataFrame schema to Tabular DataResource schema for (const [colName, colType] of Object.entries(df.schema)) { const dataType = mapPolarsTypeToJSONSchema(colType); schema.fields.push({ name: colName, type: dataType, }); } // Convert DataFrame data to row-oriented JSON // // TODO(rgbkrk): Determine how to get the polars format max rows // Since pl.setTblRows just sets env var POLARS_FMT_MAX_ROWS, // we probably just have to pick a number for now. // data = df.head(50).toRecords(); let htmlTable = ""; htmlTable += ""; schema.fields.forEach((field) => { htmlTable += ``; }); htmlTable += ""; htmlTable += ""; df.head(10).toRecords().forEach((row) => { htmlTable += ""; schema.fields.forEach((field) => { htmlTable += ``; }); htmlTable += ""; }); htmlTable += "
${escapeHTML(String(field.name))}
${escapeHTML(String(row[field.name]))}
"; return { "application/vnd.dataresource+json": { data, schema }, "text/html": htmlTable, }; } /** Canvas */ function isCanvasLike(obj) { return obj !== null && typeof obj === "object" && "toDataURL" in obj; } /** Possible HTML and SVG Elements */ function isSVGElementLike(obj) { return obj !== null && typeof obj === "object" && "outerHTML" in obj && typeof obj.outerHTML === "string" && obj.outerHTML.startsWith(" obj, }; } /** * Format an object for displaying in Deno * * @param obj - The object to be displayed * @returns MediaBundle */ async function format(obj) { if (hasDisplaySymbol(obj)) { return await obj[$display](); } if (typeof obj !== "object") { return { "text/plain": Deno[Deno.internal].inspectArgs(["%o", obj], { colors: !Deno.noColor, }), }; } if (isCanvasLike(obj)) { const dataURL = obj.toDataURL(); const parts = dataURL.split(","); const mime = parts[0].split(":")[1].split(";")[0]; const data = parts[1]; return { [mime]: data, }; } if (isVegaLike(obj)) { return extractVega(obj); } if (isDataFrameLike(obj)) { return extractDataFrame(obj); } if (isSVGElementLike(obj)) { return { "image/svg+xml": obj.outerHTML, }; } if (isHTMLElementLike(obj)) { return { "text/html": obj.outerHTML, }; } return { "text/plain": Deno[Deno.internal].inspectArgs(["%o", obj], { colors: !Deno.noColor, }), }; } /** * This function creates a tagged template function for a given media type. * The tagged template function takes a template string and returns a displayable object. * * @param mediatype - The media type for the tagged template function. * @returns A function that takes a template string and returns a displayable object. */ function createTaggedTemplateDisplayable(mediatype) { return (strings, ...values) => { const payload = strings.reduce( (acc, string, i) => acc + string + (values[i] !== undefined ? values[i] : ""), "", ); return makeDisplayable({ [mediatype]: payload }); }; } /** * Show Markdown in Jupyter frontends with a tagged template function. * * Takes a template string and returns a displayable object for Jupyter frontends. * * @example * Create a Markdown view. * * ```typescript * md`# Notebooks in TypeScript via Deno ![Deno logo](https://github.com/denoland.png?size=32) * * * TypeScript ${Deno.version.typescript} * * V8 ${Deno.version.v8} * * Deno ${Deno.version.deno} * * Interactive compute with Jupyter _built into Deno_! * ` * ``` */ const md = createTaggedTemplateDisplayable("text/markdown"); /** * Show HTML in Jupyter frontends with a tagged template function. * * Takes a template string and returns a displayable object for Jupyter frontends. * * @example * Create an HTML view. * ```typescript * html`

Hello, world!

` * ``` */ const html = createTaggedTemplateDisplayable("text/html"); /** * SVG Tagged Template Function. * * Takes a template string and returns a displayable object for Jupyter frontends. * * Example usage: * * svg` * * ` */ const svg = createTaggedTemplateDisplayable("image/svg+xml"); function isMediaBundle(obj) { if (obj == null || typeof obj !== "object" || Array.isArray(obj)) { return false; } for (const key in obj) { if (typeof key !== "string") { return false; } } return true; } async function formatInner(obj, raw) { if (raw && isMediaBundle(obj)) { return obj; } else { return await format(obj); } } internals.jupyter = { formatInner }; function enableJupyter() { const { op_jupyter_broadcast } = core.ops; async function broadcast( msgType, content, { metadata = {}, buffers = [] } = {}, ) { await op_jupyter_broadcast(msgType, content, metadata, buffers); } async function broadcastResult(executionCount, result) { try { if (result === undefined) { return; } const data = await format(result); await broadcast("execute_result", { execution_count: executionCount, data, metadata: {}, }); } catch (err) { if (err instanceof Error) { const stack = err.stack || ""; await broadcast("error", { ename: err.name, evalue: err.message, traceback: stack.split("\n"), }); } else if (typeof err == "string") { await broadcast("error", { ename: "Error", evalue: err, traceback: [], }); } else { await broadcast("error", { ename: "Error", evalue: "An error occurred while formatting a result, but it could not be identified", traceback: [], }); } } } internals.jupyter.broadcastResult = broadcastResult; /** * Display function for Jupyter Deno Kernel. * Mimics the behavior of IPython's `display(obj, raw=True)` function to allow * asynchronous displaying of objects in Jupyter. * * @param obj - The object to be displayed * @param options - Display options */ async function display(obj, options = { raw: false, update: false }) { const bundle = await formatInner(obj, options.raw); let messageType = "display_data"; if (options.update) { messageType = "update_display_data"; } let transient = {}; if (options.display_id) { transient = { display_id: options.display_id }; } await broadcast(messageType, { data: bundle, metadata: {}, transient, }); return; } globalThis.Deno.jupyter = { broadcast, display, format, md, html, svg, $display, }; } internals.enableJupyter = enableJupyter;