@cap.js/widget/cap.min.js

Client-side widget for Cap, a lightweight, modern open-source CAPTCHA alternative designed using SHA-256 PoW.

!function(){const e="0.0.6",t=function(){return window?.CAP_CUSTOM_FETCH?window.CAP_CUSTOM_FETCH(...arguments):fetch(...arguments)};window.CAP_CUSTOM_WASM_URL||[`https://cdn.jsdelivr.net/npm/@cap.js/wasm@${e}/browser/cap_wasm.min.js`,`https://cdn.jsdelivr.net/npm/@cap.js/wasm@${e}/browser/cap_wasm_bg.wasm`].forEach(e=>{const t=document.createElement("link");t.rel="prefetch",t.href=e,t.as=e.endsWith(".wasm")?"fetch":"script",document.head.appendChild(t)});class r extends HTMLElement{#e="";#t=null;#r=navigator.hardwareConcurrency||8;token=null;#s;#i;#a;#n=!1;#o;getI18nText(e,t){return this.getAttribute(`data-cap-i18n-${e}`)||t}static get observedAttributes(){return["onsolve","onprogress","onreset","onerror","data-cap-worker-count","data-cap-i18n-initial-state","[cap]"]}constructor(){super(),this.#o&&this.#o.forEach((e,t)=>{this.removeEventListener(t.slice(2),e)}),this.#o=new Map,this.boundHandleProgress=this.handleProgress.bind(this),this.boundHandleSolve=this.handleSolve.bind(this),this.boundHandleError=this.handleError.bind(this),this.boundHandleReset=this.handleReset.bind(this)}initialize(){this.#e=URL.createObjectURL(new Blob(['(()=>{if("object"!=typeof WebAssembly||"function"!=typeof WebAssembly?.instantiate)return self.onmessage=async({data:{salt:e,target:r}})=>{let o=0;let t=0;const s=new TextEncoder,n=new Uint8Array(r.length/2);for(let e=0;e<n.length;e++)n[e]=parseInt(r.substring(2*e,2*e+2),16);const a=n.length;for(;;)try{for(let r=0;r<5e4;r++){const r=e+o,t=s.encode(r),l=await crypto.subtle.digest("SHA-256",t),c=new Uint8Array(l,0,a);let f=!0;for(let e=0;e<a;e++)if(c[e]!==n[e]){f=!1;break}if(f)return void self.postMessage({nonce:o,found:!0});o++}t+=5e4}catch(e){return console.error("[cap worker]",e),void self.postMessage({found:!1,error:e.message})}},console.warn("[cap worker] wasm not supported, falling back to alternative solver. this will be significantly slower.");let e,r;self.onmessage=async({data:{salt:o,target:t,wasmUrl:s}})=>{e!==s&&(e=s,await import(s).then(e=>e.default().then(o=>{r=(o&&o.exports?o.exports:e).solve_pow})).catch(e=>{console.error("[cap worker] using fallback solver due to error:",e)}));try{const e=performance.now(),s=r(o,t),n=performance.now();self.postMessage({nonce:Number(s),found:!0,durationMs:(n-e).toFixed(2)})}catch(e){console.error("[cap worker]",e),self.postMessage({found:!1,error:e.message||String(e)})}},self.onerror=e=>{self.postMessage({found:!1,error:e})}})();'],{type:"application/javascript"}))}attributeChangedCallback(e,t,r){if(e.startsWith("on")){const t=e.slice(2),s=this.#o.get(e);if(s&&this.removeEventListener(t,s),r){const r=t=>{const r=this.getAttribute(e);"function"==typeof window[r]&&window[r].call(this,t)};this.#o.set(e,r),this.addEventListener(t,r)}}"data-cap-worker-count"===e&&this.setWorkersCount(parseInt(r)),"data-cap-i18n-initial-state"===e&&this.#i&&this.#i?.querySelector("p")?.innerText&&(this.#i.querySelector("p").innerText=this.getI18nText("initial-state","I'm a human"))}async connectedCallback(){this.#a=this,this.#s=this.attachShadow({mode:"open"}),this.#i=document.createElement("div"),this.createUI(),this.addEventListeners(),await this.initialize(),this.#i.removeAttribute("disabled");const e=this.getAttribute("data-cap-worker-count"),t=e?parseInt(e,10):null;this.setWorkersCount(t||navigator.hardwareConcurrency||8);const r=this.getAttribute("data-cap-hidden-field-name")||"cap-token";this.#a.innerHTML=`<input type="hidden" name="${r}">`}async solve(){if(!this.#n)try{this.#n=!0,this.updateUI("verifying",this.getI18nText("verifying-label","Verifying..."),!0),this.#i.setAttribute("aria-label",this.getI18nText("verifying-aria-label","Verifying you're a human, please wait")),this.dispatchEvent("progress",{progress:0});try{const e=this.getAttribute("data-cap-api-endpoint");if(!e)throw new Error("Missing API endpoint");const{challenge:r,token:s}=await(await t(`${e}challenge`,{method:"POST"})).json();let i=r;if(!Array.isArray(i)){function d(e,t){let r=function(e){let t=2166136261;for(let r=0;r<e.length;r++)t^=e.charCodeAt(r),t+=(t<<1)+(t<<4)+(t<<7)+(t<<8)+(t<<24);return t>>>0}(e),s="";function i(){return r^=r<<13,r^=r>>>17,r^=r<<5,r>>>0}for(;s.length<t;){s+=i().toString(16).padStart(8,"0")}return s.substring(0,t)}let l=0;i=Array.from({length:r.c},()=>(l+=1,[d(`${s}${l}`,r.s),d(`${s}${l}d`,r.d)]))}const a=await this.solveChallenges(i),n=await(await t(`${e}redeem`,{method:"POST",body:JSON.stringify({token:s,solutions:a}),headers:{"Content-Type":"application/json"}})).json();if(this.dispatchEvent("progress",{progress:100}),!n.success)throw new Error("Invalid solution");const o=this.getAttribute("data-cap-hidden-field-name")||"cap-token";this.querySelector(`input[name='${o}']`)&&(this.querySelector(`input[name='${o}']`).value=n.token),this.dispatchEvent("solve",{token:n.token}),this.token=n.token,this.#t&&clearTimeout(this.#t);const c=new Date(n.expires).getTime()-Date.now();return c>0&&c<864e5?this.#t=setTimeout(()=>this.reset(),c):this.error("Invalid expiration time"),this.#i.setAttribute("aria-label",this.getI18nText("verified-aria-label","We have verified you're a human, you may now continue")),{success:!0,token:this.token}}catch(h){throw this.#i.setAttribute("aria-label",this.getI18nText("error-aria-label","An error occurred, please try again")),this.error(h.message),h}}finally{this.#n=!1}}async solveChallenges(t){const r=t.length;let s=0;const i=Array(this.#r).fill(null).map(()=>{try{return new Worker(this.#e)}catch(e){throw console.error("[cap] Failed to create worker:",e),new Error("Worker creation failed")}}),a=([t,a],n)=>new Promise((o,c)=>{const d=i[n];if(!d)return void c(new Error("Worker not available"));const l=setTimeout(()=>{try{d.terminate(),i[n]=new Worker(this.#e)}catch(e){console.error("[cap] error terminating/recreating worker:",e)}c(new Error("Worker timeout"))},3e4);d.onmessage=({data:e})=>{e.found&&(clearTimeout(l),s++,this.dispatchEvent("progress",{progress:Math.round(s/r*100)}),o(e.nonce))},d.onerror=e=>{clearTimeout(l),this.error(`Error in worker: ${e.message||e}`),c(e)},d.postMessage({salt:t,target:a,wasmUrl:window.CAP_CUSTOM_WASM_URL||`https://cdn.jsdelivr.net/npm/@cap.js/wasm@${e}/browser/cap_wasm.min.js`})}),n=[];try{for(let e=0;e<t.length;e+=this.#r){const r=t.slice(e,Math.min(e+this.#r,t.length)),s=await Promise.all(r.map((e,t)=>a(e,t)));n.push(...s)}}finally{i.forEach(e=>{if(e)try{e.terminate()}catch(e){console.error("[cap] error terminating worker:",e)}})}return n}setWorkersCount(e){const t=parseInt(e,10),r=Math.min(navigator.hardwareConcurrency||8,16);this.#r=!isNaN(t)&&t>0&&t<=r?t:navigator.hardwareConcurrency||8}createUI(){this.#i.classList.add("captcha"),this.#i.setAttribute("role","button"),this.#i.setAttribute("tabindex","0"),this.#i.setAttribute("aria-label",this.getI18nText("verify-aria-label","Click to verify you're a human")),this.#i.setAttribute("aria-live","polite"),this.#i.setAttribute("disabled","true"),this.#i.innerHTML=`<div class="checkbox" part="checkbox"></div><p part="label">${this.getI18nText("initial-state","I'm a human")}</p><a part="attribution" aria-label="Secured by Cap" href="https://capjs.js.org/" class="credits" target="_blank" rel="follow noopener">Cap</a>`,this.#s.innerHTML='<style>.captcha,.captcha * {box-sizing:border-box;}.captcha{background-color:var(--cap-background,#fdfdfd);border:1px solid var(--cap-border-color,#dddddd8f);border-radius:var(--cap-border-radius,14px);user-select:none;height:var(--cap-widget-height, 58px);width:var(--cap-widget-width, 230px);display:flex;align-items:center;padding:var(--cap-widget-padding,14px);gap:var(--cap-gap,15px);cursor:pointer;transition:filter .2s,transform .2s;position:relative;-webkit-tap-highlight-color:rgba(255,255,255,0);overflow:hidden;color:var(--cap-color,#212121)}.captcha:hover{filter:brightness(98%)}.checkbox{width:var(--cap-checkbox-size,25px);height:var(--cap-checkbox-size,25px);border:var(--cap-checkbox-border,1px solid #aaaaaad1);border-radius:var(--cap-checkbox-border-radius,6px);background-color:var(--cap-checkbox-background,#fafafa91);transition:opacity .2s;margin-top:var(--cap-checkbox-margin,2px);margin-bottom:var(--cap-checkbox-margin,2px)}.captcha *{font-family:var(--cap-font,system,-apple-system,"BlinkMacSystemFont",".SFNSText-Regular","San Francisco","Roboto","Segoe UI","Helvetica Neue","Lucida Grande","Ubuntu","arial",sans-serif)}.captcha p{margin:0;font-weight:500;font-size:15px;user-select:none;transition:opacity .2s}.captcha[data-state=verifying]\n.checkbox{background: none;display:flex;align-items:center;justify-content:center;transform: scale(1.1);border: none;border-radius: 50%;background: conic-gradient(var(--cap-spinner-color,#000) 0%, var(--cap-spinner-color,#000) var(--progress, 0%), var(--cap-spinner-background-color,#eee) var(--progress, 0%), var(--cap-spinner-background-color,#eee) 100%);position: relative;}.captcha[data-state=verifying] .checkbox::after {content: "";background-color: var(--cap-background,#fdfdfd);width: calc(100% - var(--cap-spinner-thickness,5px));height: calc(100% - var(--cap-spinner-thickness,5px));border-radius: 50%;margin:calc(var(--cap-spinner-thickness,5px) / 2)}.captcha[data-state=done] .checkbox{border:1px solid transparent;background-image:var(--cap-checkmark,url("data:image/svg+xml,%3Csvg%20xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F2000%2Fsvg%22%20width%3D%2224%22%20height%3D%2224%22%20viewBox%3D%220%200%2024%2024%22%3E%3Cstyle%3E%40keyframes%20anim%7B0%25%7Bstroke-dashoffset%3A23.21320343017578px%7Dto%7Bstroke-dashoffset%3A0%7D%7D%3C%2Fstyle%3E%3Cpath%20fill%3D%22none%22%20stroke%3D%22%2300a67d%22%20stroke-linecap%3D%22round%22%20stroke-linejoin%3D%22round%22%20stroke-width%3D%222%22%20d%3D%22m5%2012%205%205L20%207%22%20style%3D%22stroke-dashoffset%3A0%3Bstroke-dasharray%3A23.21320343017578px%3Banimation%3Aanim%20.5s%20ease%22%2F%3E%3C%2Fsvg%3E"));background-size:cover}.captcha[data-state=error] .checkbox{border:1px solid transparent;background-image:var(--cap-error-cross,url("data:image/svg+xml,%3Csvg xmlns=\'http://www.w3.org/2000/svg\' width=\'96\' height=\'96\' viewBox=\'0 0 24 24\'%3E%3Cpath fill=\'%23f55b50\' d=\'M11 15h2v2h-2zm0-8h2v6h-2zm1-5C6.47 2 2 6.5 2 12a10 10 0 0 0 10 10a10 10 0 0 0 10-10A10 10 0 0 0 12 2m0 18a8 8 0 0 1-8-8a8 8 0 0 1 8-8a8 8 0 0 1 8 8a8 8 0 0 1-8 8\'/%3E%3C/svg%3E"));background-size:cover}.captcha[disabled]{cursor:not-allowed}.captcha[disabled][data-state=verifying]{cursor:progress}.captcha[disabled][data-state=done]{cursor:default}.captcha .credits{position:absolute;bottom:10px;right:10px;font-size:var(--cap-credits-font-size,12px);color:var(--cap-color,#212121);opacity:var(--cap-opacity-hover,0.8);text-underline-offset: 1.5px;}</style>',this.#s.appendChild(this.#i)}addEventListeners(){this.#i&&(this.#i.querySelector("a").addEventListener("click",e=>{e.stopPropagation(),e.preventDefault(),window.open("https://capjs.js.org","_blank")}),this.#i.addEventListener("click",()=>{this.#i.hasAttribute("disabled")||this.solve()}),this.#i.addEventListener("keydown",e=>{"Enter"!==e.key&&" "!==e.key||this.#i.hasAttribute("disabled")||(e.preventDefault(),e.stopPropagation(),this.solve())}),this.addEventListener("progress",this.boundHandleProgress),this.addEventListener("solve",this.boundHandleSolve),this.addEventListener("error",this.boundHandleError),this.addEventListener("reset",this.boundHandleReset))}updateUI(e,t,r=!1){this.#i&&(this.#i.setAttribute("data-state",e),this.#i.querySelector("p").innerText=t,r?this.#i.setAttribute("disabled","true"):this.#i.removeAttribute("disabled"))}handleProgress(e){if(!this.#i)return;const t=this.#i.querySelector("p"),r=this.#i.querySelector(".checkbox");t&&r&&(r.style.setProperty("--progress",`${e.detail.progress}%`),t.innerText=`${this.getI18nText("verifying-label","Verifying...")} ${e.detail.progress}%`),this.executeAttributeCode("onprogress",e)}handleSolve(e){this.updateUI("done",this.getI18nText("solved-label","You're a human"),!0),this.executeAttributeCode("onsolve",e)}handleError(e){this.updateUI("error",this.getI18nText("error-label","Error. Try again.")),this.executeAttributeCode("onerror",e)}handleReset(e){this.updateUI("",this.getI18nText("initial-state","I'm a human")),this.executeAttributeCode("onreset",e)}executeAttributeCode(e,t){const r=this.getAttribute(e);r&&new Function("event",r).call(this,t)}error(e="Unknown error"){console.error("[cap]",e),this.dispatchEvent("error",{isCap:!0,message:e})}dispatchEvent(e,t={}){const r=new CustomEvent(e,{bubbles:!0,composed:!0,detail:t});super.dispatchEvent(r)}reset(){this.#t&&(clearTimeout(this.#t),this.#t=null),this.dispatchEvent("reset"),this.token=null;const e=this.getAttribute("data-cap-hidden-field-name")||"cap-token";this.querySelector(`input[name='${e}']`)&&(this.querySelector(`input[name='${e}']`).value="")}get tokenValue(){return this.token}disconnectedCallback(){this.removeEventListener("progress",this.boundHandleProgress),this.removeEventListener("solve",this.boundHandleSolve),this.removeEventListener("error",this.boundHandleError),this.removeEventListener("reset",this.boundHandleReset),this.#o.forEach((e,t)=>{this.removeEventListener(t.slice(2),e)}),this.#o.clear(),this.#s&&(this.#s.innerHTML=""),this.reset(),this.cleanup()}cleanup(){this.#t&&(clearTimeout(this.#t),this.#t=null),this.#e&&(URL.revokeObjectURL(this.#e),this.#e="")}}class s{constructor(e={},t){let r=t||document.createElement("cap-widget");if(Object.entries(e).forEach(([e,t])=>{r.setAttribute(e,t)}),!e.apiEndpoint)throw r.remove(),new Error("Missing API endpoint");r.setAttribute("data-cap-api-endpoint",e.apiEndpoint),this.widget=r,this.solve=this.widget.solve.bind(this.widget),this.reset=this.widget.reset.bind(this.widget),this.addEventListener=this.widget.addEventListener.bind(this.widget),Object.defineProperty(this,"token",{get:()=>r.token,configurable:!0,enumerable:!0}),t||(r.style.display="none",document.documentElement.appendChild(r))}}window.Cap=s,customElements.get("cap-widget")||window?.CAP_DONT_SKIP_REDEFINE?console.warn("[cap] the cap-widget element has already been defined, skipping re-defining it.\nto prevent this, set window.CAP_DONT_SKIP_REDEFINE to true"):customElements.define("cap-widget",r),"object"==typeof exports&&"undefined"!=typeof module?module.exports=s:"function"==typeof define&&define.amd&&define([],function(){return s}),"undefined"!=typeof exports&&(exports.default=s)}();