machine-envy » Uncategorized

Looking into PiCloud’s Sandbox

James Casbon — Mon, 26 Jul 2010 08:11:23 +0000

EDIT: this was due to python 2.7 incompatibility and incorrect documentation. These examples all work with python 2.6

PiCloud looks very interesting. Execute on demand python could give you a much greater level of control over cloud computing use. Now, of course, sandboxing python is not easy, despite some well known implementations.

So PiCloud don’t write much about the limitations of the sandbox, so I gave it a quick poke to see what happens:


import cloud

def blocker(x=1):
    while True:
        x = x + 1
    return x

jid = cloud.call(blocker)
cloud.join(jid)
print cloud.result(jid)
print cloud.info(jid, ['stde

This produces:

Traceback (most recent call last):
cloud.cloud.CloudException: Job 38: Traceback (most recent call last):
  File "/root/.local/lib/python2.6/site-packages/cloudserver/workers/employee/child.py", line 334, in run
  File "tp.py", line 4, in blocker
    while True:
SystemError: unknown opcode

Which is an interesting error!

Trying this:


def blocker(x=1):
    while x < 10:
        x = x + 1
    return x

returns

cloud.cloud.CloudException: Job 39: None

So we're not allowed while loops?

Friday quiz: where and when does this describe?

James Casbon — Fri, 09 Jul 2010 12:47:53 +0000

But these evils, though great, were small compared to
those far more deep-seated signs of disease which now
showed themselves throughout the country. One of these
was the obliteration of thrift from the minds of the ***
people. The *** are naturally thrifty; but, with such
masses of money and with such uncertainty as to its future
value, the ordinary motives for saving and care diminished,
and a loose luxury spread throughout the country. A still
worse outgrowth was the increase of speculation and
gambling. With the plethora of paper currency in *** ap·
peared the first evidences of that cancerous disease which
always follows large issues of irredeemable currency,—a
disease more permanently injurious to a nation than war,
pestilence or famine. For at the great metropolitan centers
grew a luxurious, speculative, stock-gambling body, which,
like a malignant tumor, absorbed into itself the strength of
the nation and sent out its cancerous fibres to the remotest
hamlets. At these city centers abundant wealth seemed to
be piled up: in the country at large there grew a dislike
of steady labor and a contempt for moderate gains and sim-
ple living.

…

This outgrowth was a
vast debtor class in the nation, directly interested in the
depreciation of the currency in which they were to pay their
debts. The nucleus of this class was formed by those who
had purchased the church lands from the government. Only
small payments down had been required and the remainder
was to be paid in deferred installments: an indebtedness of
a multitude of people had thus been created to the amount
of hundreds of millions. This body of debtors soon saw, of
course, that their interest was to depreciate the currency in
which their debts were to be paid; and these were speedily
joined by a far more influential class;—by that class whose
speculative tendencies had been stimulated by the abun-
dance of paper money, and who had gone largely into debt,
looking for a rise in nominal values. Soon demagogues of
the viler sort in the political clubs began to pander to it;
a little later important persons in this debtor class were to
be found intriguing in the Assembly—first in its seats and
later in more conspicuous places of public trust. Before long,
the debtor class became a powerful body extending through
all ranks of society. From the stock-gambler who sat in the
Assembly to the small land speculator in the rural districts;
from the sleek inventor of canards on the *** Exchange
to the lying stock-jobber in the market town, all pressed
vigorously for new issues of paper; all were apparently able
to demonstrate to the people that in new issues of paper lay
the only chance for national prosperity.

Making textmate virtualenv aware

James Casbon — Tue, 16 Dec 2008 19:19:52 +0000

So I am using textmate for my python development, but I wanted it to pick up any virtualenv configured in a project. Here’s how to hack the python bundle…

First off, the run script command needs to be aware of the virtualenv stuff. So open up the bundle editor, and replace this:

is_test_script = ENV["TM_FILEPATH"] =~ /(?:\b|_)(?:test)(?:\b|_)/ or File.read(ENV["TM_FILEPATH"]) =~ /\bimport\b.+(?:unittest)/

TextMate::Executor.run(ENV["TM_PYTHON"] || "python", "-u", ENV["TM_FILEPATH"]) do |str, type|

with:

is_test_script = ENV["TM_FILEPATH"] =~ /(?:\b|_)(?:test)(?:\b|_)/ or File.read(ENV["TM_FILEPATH"]) =~ /\bimport\b.+(?:unittest)/


# default python

python = ENV["TM_PYTHON"] || "python"
# try for virtualenv if it exists

if ENV.has_key?("TM_PROJECT_DIRECTORY")

    virtualenv_python = ENV["TM_PROJECT_DIRECTORY"] + "/bin/python"

    if FileTest.exists?(virtualenv_python)

      python = virtualenv_python

    end

end

TextMate::Executor.run(python, "-u", ENV["TM_FILEPATH"]) do |str, type|

Now, we also want the unit tests to pick up that environment as well, so you need to do the same with the Run Project Unit Tests command. I am using nose to collect tests, and the nosexml plugin to format the results. You should install them if you need to. Replace:

# Find all files that end with "Test.py" and run # them.

find . -name "*Test.py" -exec "${TM_PYTHON:-python}" '{}' \;|pre

with:

cd $TM_PROJECT_DIRECTORY if [ -f bin/activate ] then source bin/activate fi nosetests --xml --xml-formatter=nosexml.TextMateFormatter

PS, it seems like the python bundle needs some love, anyone know the maintainer?

An interesting new campaign

James Casbon — Wed, 03 Dec 2008 21:01:18 +0000

RentalRights looks like it is finally getting a campaign together to organise in support of people who rent. If you rent and live in the uk you should check it out. No other country seems to treat tenants so badly.

Links for January 12th through March 7th

James Casbon — Sat, 08 Mar 2008 07:27:06 +0000

Insteresting stuff for January 12th through March 7th:

Running 32-bit Applications on 64-bit Debian GNU/Linux – nt tree, see apt-file code example below. To find out what libraries are needed use the ldd command – be aware that the file you think starts the application is often a script, and you may have to dig a bit to find the actual binary. The example below is
Arcane Market Is Next to Face Big Credit Test – New York Times –
Batteries From Nature –
Some Datasets Available on the Web Â» Data Wrangling Blog –
AV-Comparatives –
Candidates Push for a N.H. Recount – The Caucus – Politics – New York Times Blog –

Links for January 4th through January 11th

James Casbon — Sat, 12 Jan 2008 00:30:19 +0000

Insteresting stuff for January 4th through January 11th:

financial reality Â» Blog Archive Â» Minsky Has His Moment –
50 Best WordPress Plugins for Power Blogging : MoneyRumour.com –
ie7-js – Google Code –
100 Excellent Free WordPress Themes | Developer’s Toolbox | Smashing Magazine –
Davis Freebergâ��s Digital Connection Â» Bad COPP No Netflix – eir digital strategies to fail. While I understand the need for the studios to protect their content, I believe that these measures go too far. It makes little sense to block my ability to copy low res internet movies, when I can always rip the DVD straig

Links for December 31st through January 3rd

James Casbon — Fri, 04 Jan 2008 00:34:54 +0000

Insteresting stuff for December 31st through January 3rd:

ZSFA — Rails Is A Ghetto (2007-12-31) –
SRA / Society for Risk Analysis / April 2006 Press Release –
American Scientist Online – The Easiest Hard Problem –
Pay Option ARM’s – California’s Billion Pound Gorilla | Loan Modification & Loan Workout News –
Index of /logtags/howto – e pre-shared key is (afaik) the weakest part in the security of this setup. I’ll explain how to use X.509 certificates instead of pre-shared keys in a later post. If you’re also doing firewalling or some kind of NAT on one of the IPsec endpoints, make sur
Tune the Web – jaanix –
Market Ticker: The Year In Review And a Look Ahead for 2008 –

Links for December 21st through December 30th

James Casbon — Mon, 31 Dec 2007 14:11:26 +0000

These are my links for December 21st through December 30th:

Krugman on the subprime thing

James Casbon — Sat, 22 Dec 2007 18:31:12 +0000

Worth watching

Tenori On – I want

James Casbon — Sun, 23 Sep 2007 19:05:09 +0000

As seen on the excellent music thing