WIP, pretty much there with serving image, just some layout stuff.

This commit is contained in:
zeyus 2024-11-03 21:58:43 +01:00
parent e3e483e40b
commit 477301157e
Signed by: zeyus
GPG key ID: CE89DA73E2E2C2CD
3 changed files with 169 additions and 53 deletions

1
node/.gitignore vendored
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@ -2,3 +2,4 @@ node_modules/
.DS_Store
hits.db
hits.db-*
example_counter_bg.png

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@ -1,10 +1,10 @@
import e, { Request, Response, NextFunction } from 'express';
import { type Database as DB } from 'better-sqlite3';
import { type Statement } from 'better-sqlite3';
import Database from 'better-sqlite3';
// import sharp for images
import sharp, { FormatEnum, AvailableFormatInfo, Sharp } from 'sharp';
import sharp, { FormatEnum, AvailableFormatInfo, Sharp, Metadata } from 'sharp';
import * as fs from 'fs';
import * as https from 'https';
// Map file extensions to sharp formats
const imageFormatMap: { [key: string]: keyof FormatEnum | AvailableFormatInfo } = {
@ -16,6 +16,16 @@ const imageFormatMap: { [key: string]: keyof FormatEnum | AvailableFormatInfo }
gif: 'gif'
};
// no need for third party library
const mimeTypeMap: { [key: string]: string } = {
jpg: 'image/jpeg',
jpeg: 'image/jpeg',
png: 'image/png',
webp: 'image/webp',
tiff: 'image/tiff',
gif: 'image/gif'
};
interface HitResult {
hits: number;
}
@ -33,6 +43,50 @@ interface HitCounterRenderer {
render(): Promise<any>;
}
function fileExt(file: string): string {
const fileExt = file.split('.').pop();
if (!fileExt) {
throw new Error('Invalid file extension');
}
return fileExt.toLowerCase();
}
function extToFormat(ext: string): keyof FormatEnum | AvailableFormatInfo {
const format = imageFormatMap[ext];
if (!format) {
throw new Error('Unsupported file extension');
}
return format;
}
/**
* Determine whether the given `path` is a http(s) URL. This method
* accepts a string value and a URL instance.
*
* inspiration:
* Marcus Pöhls
* https://futurestud.io/tutorials/node-js-check-if-a-path-is-a-file-url
*
* @param {String|URL} path
*
* @returns {Boolean}
*/
function isWebURI(path) {
// `path` is neither a string nor a URL -> early return
if (typeof path !== 'string' && !(path instanceof URL)) {
return false
}
try {
const url = new URL(path)
return url.protocol === 'http:' || url.protocol === 'https:'
} catch (error) {
return false
}
}
class BaseHitCounterRenderer implements HitCounterRenderer {
protected counter: HitCounter;
protected config: HitCounterConfig;
@ -53,17 +107,31 @@ class BaseHitCounterRenderer implements HitCounterRenderer {
class ImageHitCounterRenderer extends BaseHitCounterRenderer {
private imageType: string;
private imageFormat: keyof FormatEnum | AvailableFormatInfo;
private baseImage: Buffer;
private baseImageMetadata: Metadata;
constructor(counter: HitCounter, config: HitCounterConfig) {
super(counter, config);
const fileExt = this.config.imageFile.split('.').pop();
if (!fileExt) {
throw new Error('Invalid file extension');
}
this.imageType = fileExt;
this.imageFormat = imageFormatMap[fileExt.toLowerCase()];
if (!this.imageFormat) {
throw new Error('Unsupported file extension');
this.imageType = fileExt(this.config.imageFile);
this.imageFormat = extToFormat(this.imageType);
}
private async downloadImage(): Promise<Buffer> {
return new Promise((resolve, reject) => {
let buf = Buffer.alloc(0);
const request = https.get(this.config.backgroundImageUrl, (response) => {
response.on('data', (chunk) => {
buf = Buffer.concat([buf, chunk]);
});
response.on('end', () => {
resolve(buf);
});
});
request.on('error', (err) => {
fs.unlink(this.config.backgroundCacheFile, () => {
reject(err);
});
});
});
}
private async cachedBackgroundImage(overWrite: boolean = false): Promise<Sharp> {
@ -78,71 +146,91 @@ class ImageHitCounterRenderer extends BaseHitCounterRenderer {
}
// store the image in the cache
const fileExt = dest.split('.').pop();
if (!fileExt) {
throw new Error('Invalid file extension');
}
const format = imageFormatMap[fileExt.toLowerCase()];
if (!format) {
throw new Error('Unsupported file extension');
}
const ext = fileExt(this.config.backgroundImageUrl);
const format = extToFormat(ext);
if (isWebURI(this.config.backgroundImageUrl)) {
const buf = await this.downloadImage();
const image = sharp(buf).toFormat(format);
await image.toFile(dest);
return image;
} else {
if (fs.existsSync(this.config.backgroundImageUrl)) {
const image = sharp(this.config.backgroundImageUrl).toFormat(format);
await image.toFile(dest);
return image;
} else {
throw new Error('Background image does not exist');
}
}
}
async render(): Promise<Sharp> {
const hits = await this.counter.getHits();
async prepareBaseImage(): Promise<void> {
if (typeof this.baseImage !== 'undefined') {
return;
}
const bgImage = await this.cachedBackgroundImage();
const bgInfo = await bgImage.metadata();
const text = this.config.customText;
const secondaryText = this.config.secondaryText;
const textColor = this.config.textColorRGB;
const secondaryTextColor = this.config.secondaryTextColorRGB;
const numberColor = this.config.numberColorRGB;
const frameColor = this.config.frameColorRGB;
const drawFrame = this.config.drawFrame;
const textX = this.config.textPositionX;
const textY = this.config.textPositionY;
const numberX = this.config.numberPositionX;
const numberY = this.config.numberPositionY;
const imgWidth = bgInfo.width;
const imgHeight = bgInfo.height;
if (typeof imgWidth === 'undefined' || typeof imgHeight === 'undefined') {
throw new Error('Invalid image dimensions');
}
const svgFrame = `
<svg width="${bgInfo.width}" height="${bgInfo.height}" xmlns="http://www.w3.org/2000/svg">
<rect x="0" y="0" width="${bgInfo.width}" height="${bgInfo.height}" stroke="rgb(${frameColor.r},${frameColor.g},${frameColor.b})" stroke-width="2" fill="none"/>
<rect x="${this.config.borderWidth}" y="${this.config.borderWidth}" width="${imgWidth - 2 * this.config.borderWidth}" height="${imgHeight - 2 * this.config.borderWidth}" fill="none" stroke-alignment="inner" stroke="rgb(${this.config.frameColorRGB.r},${this.config.frameColorRGB.g},${this.config.frameColorRGB.b})" stroke-width="${this.config.borderWidth}"/>
</svg>
`;
const svgOverlay = `
<svg width="${bgInfo.width}" height="${bgInfo.height}" xmlns="http://www.w3.org/2000/svg">
<text x="${textX}" y="${textY}" fill="rgb(${textColor.r},${textColor.g},${textColor.b})" font-size="12">${text}</text>
<text x="${textX}" y="${textY + 15}" fill="rgb(${secondaryTextColor.r},${secondaryTextColor.g},${secondaryTextColor.b})" font-size="12">${secondaryText}</text>
<text x="${numberX}" y="${numberY}" fill="rgb(${numberColor.r},${numberColor.g},${numberColor.b})" font-size="12">${hits}</text>
<text x="${this.config.textPositionX}" y="${this.config.textPositionY}" fill="rgb(${this.config.textColorRGB.r},${this.config.textColorRGB.g},${this.config.textColorRGB.b})" font-size="${this.config.fontSize}" font-family="${this.config.fontFace}">${this.config.customText}</text>
<text x="${this.config.textPositionX}" y="${this.config.textPositionY + 15}" fill="rgb(${this.config.textColorRGB.r},${this.config.textColorRGB.g},${this.config.textColorRGB.b})" font-size="${this.config.fontSize}" font-family="${this.config.fontFace}">${this.config.secondaryText}</text>
</svg>
`;
const overlay = sharp(Buffer.from(svgOverlay));
if (drawFrame) {
if (this.config.drawFrame) {
const frame = sharp(Buffer.from(svgFrame));
const composite = bgImage.composite([
{ input: await overlay.toBuffer(), gravity: 'northwest' },
{ input: await frame.toBuffer(), gravity: 'northwest' }
]);
return composite;
const preparedImg = composite.toFormat(this.imageFormat);
this.baseImageMetadata = await preparedImg.metadata();
this.baseImage = await preparedImg.toBuffer();;
}
const composite = bgImage.composite([
{ input: await overlay.toBuffer(), gravity: 'northwest' }
]);
return composite;
const preparedImg = composite.toFormat(this.imageFormat);
this.baseImageMetadata = await preparedImg.metadata();
this.baseImage = await preparedImg.toBuffer();
}
async render(): Promise<Buffer> {
const hits = await this.counter.getHits();
const numberColor = this.config.numberColorRGB;
const numberX = this.config.numberPositionX;
const numberY = this.config.numberPositionY;
await this.prepareBaseImage();
const overlay = `
<svg width="${this.baseImageMetadata.width}" height="${this.baseImageMetadata.height}" xmlns="http://www.w3.org/2000/svg">
<text x="${numberX}" y="${numberY}" fill="rgb(${numberColor.r},${numberColor.g},${numberColor.b})" font-size="12">${hits}</text>
</svg>
`;
const composite = sharp(this.baseImage).composite([
{ input: Buffer.from(overlay), gravity: 'northwest' }
]);
return composite.toBuffer();
}
}
@ -163,6 +251,9 @@ interface HitCounterConfig {
textPositionY: number; // Y position of the text
numberPositionX: number; // X position of the number
numberPositionY: number; // Y position of the number
fontSize: number; // Font size
fontFace: string; // Font face
borderWidth: number; // Border width
textColorRGB: RGBColor; // Text color
secondaryTextColorRGB: RGBColor; // Secondary text color
numberColorRGB: RGBColor; // Number color
@ -184,12 +275,15 @@ const defaultHitCounterConfig: HitCounterConfig = {
secondaryText: 'Super cyber, super cool!',
textPositionX: 5,
textPositionY: 5,
numberPositionX: 5,
numberPositionX: 160,
numberPositionY: 15,
fontSize: 12,
fontFace: 'Arial',
borderWidth: 3,
textColorRGB: { r: 253, g: 252, b: 1 },
secondaryTextColorRGB: { r: 0, g: 255, b: 0 },
numberColorRGB: { r: 255, g: 255, b: 255 },
frameColorRGB: { r: 255, g: 238, b: 0 },
frameColorRGB: { r: 255, g: 0, b: 0 },
drawFrame: true,
renderer: ImageHitCounterRenderer
};
@ -201,6 +295,7 @@ class HitCounter {
private preparedGet: Statement;
private preparedIncrement: Statement;
private preparedReset: Statement;
private mimeType: string;
constructor(renderer: Type<BaseHitCounterRenderer>, config?: HitCounterConfig) {
this.config = { ...defaultHitCounterConfig, ...config };
@ -208,6 +303,7 @@ class HitCounter {
this.openDB();
this.setupDB();
this.setupStatements();
this.mimeType = mimeTypeMap[fileExt(this.config.imageFile)];
}
private openDB(): void {
@ -266,6 +362,14 @@ class HitCounter {
this.preparedReset.run(this.config.siteId);
}
async render(): Promise<any> {
return this.renderer.render();
}
getMimeType(): string {
return this.mimeType;
}
// destructor
destroy(): void {
this.closeDB();

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@ -4,10 +4,12 @@ import { HitCounter, ImageHitCounterRenderer } from "./hit-counter";
const app: Express = express();
const PORT: number = 8000;
const hitCounter = new HitCounter(ImageHitCounterRenderer);
const imageMimeType = hitCounter.getMimeType();
app.get("/", (req: Request, res: Response) => {
res.send("Hello World!");
hitCounter.increment();
res.send("Hello dear interlocutor! Your visit has been noted.");
});
app.get("/hits", async (req: Request, res: Response) => {
@ -15,7 +17,16 @@ app.get("/hits", async (req: Request, res: Response) => {
res.send(`This site has ${hits} hits!`);
});
app.get("/reset", async (req: Request, res: Response) => {
await hitCounter.reset();
res.send("Hit counter has been reset!");
});
app.get("/image", async (req: Request, res: Response) => {
const image = await hitCounter.render();
res.setHeader("Content-Type", imageMimeType);
res.send(image);
});
app.listen(PORT, () => {
console.log(`[server]: Express server started on port ${PORT}`);