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Date: Fri, 9 Aug 2013 13:48:20 +0200
Message-ID: <CANEZrP2c6nsf2z5_hKDfHdO1HEJ+Y+aoiSdfYPMxK_jzrvLEow@mail.gmail.com>
From: Mike Hearn <mike@plan99.net>
To: Wendell <w@grabhive.com>
Content-Type: multipart/alternative; boundary=001a11c2db58e6ea0c04e3825972
Cc: Bitcoin Dev <bitcoin-development@lists.sourceforge.net>
Subject: Re: [Bitcoin-development] SPV client in pure JavaScript?
Precedence: list

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JavaScript is turing complete so of course it can be done. The real
question you're asking is, can it be done in a web app? I think the answer
is I think "no" because web apps aren't allowed to make raw TCP socket
connections.

Now there may be a way around that by using browser-specific things like
extensions or "installable apps" which give your code greater access
permissions. This approach means you essentially use Chrome as your app
platform instead of a JVM, the assumption presumably being that more users
have Chrome than a JVM. The flip side is that users who don't would
probably balk at the idea of installing an entire browser in order to run a
wallet app, whereas a JVM can be bundled and the resulting app acts like
any other. I don't know of a convenient way to "statically link" Chrome
into a regular-looking application.

I personally wouldn't find such a design compelling. Whilst Java isn't
exactly a great language, JavaScript is significantly worse in virtually
all aspects. I don't understand why anyone would want to use JavaScript
outside the browser - you get less safety, less performance, fewer
features, less mature tools and so on. If the end result is an installable
app like any other, all you did is cripple yourself vs the competition
that's using languages/platforms designed for it.


On Fri, Aug 9, 2013 at 1:32 PM, Wendell <w@grabhive.com> wrote:

> To those of you in the know about modern browser tech:
>
> Does it seem at all conceivable that an SPV wallet could be built entirely
> in JavaScript? And if indeed it is within the realm of the possible, how
> would such a thing be safely distributed for use? Would a signed Chrome
> Plugin be an ideal vehicle?
>
> -wendell
>
> grabhive.com | twitter.com/grabhive | gpg: 6C0C9411
>
>
>
> ------------------------------------------------------------------------------
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Content-Type: text/html; charset=UTF-8
Content-Transfer-Encoding: quoted-printable

<div dir=3D"ltr">JavaScript is turing complete so of course it can be done.=
 The real question you&#39;re asking is, can it be done in a web app? I thi=
nk the answer is I think &quot;no&quot; because web apps aren&#39;t allowed=
 to make raw TCP socket connections.<div>
<br></div><div>Now there may be a way around that by using browser-specific=
 things like extensions or &quot;installable apps&quot; which give your cod=
e greater access permissions. This approach means you essentially use Chrom=
e as your app platform instead of a JVM, the assumption presumably being th=
at more users have Chrome than a JVM. The flip side is that users who don&#=
39;t would probably balk at the idea of installing an entire browser in ord=
er to run a wallet app, whereas a JVM can be bundled and the resulting app =
acts like any other. I don&#39;t know of a convenient way to &quot;statical=
ly link&quot; Chrome into a regular-looking application.</div>
<div><br></div><div>I personally wouldn&#39;t find such a design compelling=
. Whilst Java isn&#39;t exactly a great language, JavaScript is significant=
ly worse in virtually all aspects. I don&#39;t understand why anyone would =
want to use JavaScript outside the browser - you get less safety, less perf=
ormance, fewer features, less mature tools and so on. If the end result is =
an installable app like any other, all you did is cripple yourself vs the c=
ompetition that&#39;s using languages/platforms designed for it.</div>
<div><br></div></div><div class=3D"gmail_extra"><br><br><div class=3D"gmail=
_quote">On Fri, Aug 9, 2013 at 1:32 PM, Wendell <span dir=3D"ltr">&lt;<a hr=
ef=3D"mailto:w@grabhive.com" target=3D"_blank">w@grabhive.com</a>&gt;</span=
> wrote:<br>
<blockquote class=3D"gmail_quote" style=3D"margin:0 0 0 .8ex;border-left:1p=
x #ccc solid;padding-left:1ex">To those of you in the know about modern bro=
wser tech:<br>
<br>
Does it seem at all conceivable that an SPV wallet could be built entirely =
in JavaScript? And if indeed it is within the realm of the possible, how wo=
uld such a thing be safely distributed for use? Would a signed Chrome Plugi=
n be an ideal vehicle?<br>

<br>
-wendell<br>
<br>
<a href=3D"http://grabhive.com" target=3D"_blank">grabhive.com</a> | <a hre=
f=3D"http://twitter.com/grabhive" target=3D"_blank">twitter.com/grabhive</a=
> | gpg: 6C0C9411<br>
<br>
<br>-----------------------------------------------------------------------=
-------<br>
Get 100% visibility into Java/.NET code with AppDynamics Lite!<br>
It&#39;s a free troubleshooting tool designed for production.<br>
Get down to code-level detail for bottlenecks, with &lt;2% overhead.<br>
Download for free and get started troubleshooting in minutes.<br>
<a href=3D"http://pubads.g.doubleclick.net/gampad/clk?id=3D48897031&amp;iu=
=3D/4140/ostg.clktrk" target=3D"_blank">http://pubads.g.doubleclick.net/gam=
pad/clk?id=3D48897031&amp;iu=3D/4140/ostg.clktrk</a><br>___________________=
____________________________<br>

Bitcoin-development mailing list<br>
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velopment</a><br>
<br></blockquote></div><br></div>

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