- Pharo-users - lists.pharo.org

Re: [Pharo-users] Persistence of data across sessions

by graham telfer

Hi, Maybe you are right about the garbage collector. This is the first thing I've tried in Smalltalk. I expected the image I saved would have the account details but no, I had to start over again and make a new account. It's not a big deal and I'll try some of the methods of storing data mentioned in other replies. > Date: Mon, 5 Sep 2011 22:32:04 -0700 > From: jeff(a)rogerthedog.com > To: pharo-users(a)lists.gforge.inria.fr > Subject: Re: [Pharo-users] Persistence of data across sessions > > I don't know about that particular tutorial but if you saved the image then > when you restart the objects will all still be in memory. > > Perhaps there's a code issue. When you create an account is it referenced by > anything? Maybe it's being gargbage collected when the app closes. > Difficult to say for sure without seeing the code. > > > -- > View this message in context: http://forum.world.st/Persistence-of-data-across-sessions-tp3787836p3792618… > Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com. >

Sept. 6, 2011

Re: [Pharo-users] Persistence of data across sessions

by Davorin Rusevljan

On Sat, Sep 3, 2011 at 2:54 PM, graham telfer <gakousei53(a)hotmail.com> wrote: > Hi there, > > I completed the Bank Account tutorial written for Squeak. It worked fine but > I have a question about persistence of data. After I built the bank account > and gave it a balance history I saved and quit. Later I wanted to go back to > it. The account and its details were gone and I could only create a new > account. > > How is data saved across sessions in Pharo? I am bit puzzled by your question, since when you save Pharo image, all your objects get saved, and when you load that image they are still there live and kicking. Your example sounds like it is for Seaside (since you mention sessions) - which is web development framework. If that is correct, seaside expires sessions after some time, for obvious reasons. So you should make your data objects accessible from the seaside application, not just current session. Aside from that, if you would like to store your object also _outside_ of an image, there dozens of ways to accomplish that task. From simple serialization to binary files (fuel and friends), serialization to XML, object smalltalk databases (SandstoneDB, Magma), NoSQL databases (CouchDB, and similar), to relational databases. Davorin Rusevljan http://www.cloud2'08.com/

Sept. 6, 2011

Re: [Pharo-users] Persistence of data across sessions

by StÃ©phane Ducasse

HI graham there are different ways to do that. you can use - a XMLWriter (See XMLSupport) - a binary object serializer (there smartref stream in the image but I sugest you to have a look at Fuel) - you can use storeOn: and readFromStream: (here the idea is that objects produce a texte representation of themslevs that when read using readFrom: recreate the object itself Stef On Sep 3, 2011, at 2:54 PM, graham telfer wrote: > Hi there, > > I completed the Bank Account tutorial written for Squeak. It worked fine but I have a question about persistence of data. After I built the bank account and gave it a balance history I saved and quit. Later I wanted to go back to it. The account and its details were gone and I could only create a new account. > > How is data saved across sessions in Pharo?

Sept. 6, 2011

Re: [Pharo-users] Persistence of data across sessions

by Jeff Gray

I don't know about that particular tutorial but if you saved the image then when you restart the objects will all still be in memory. Perhaps there's a code issue. When you create an account is it referenced by anything? Maybe it's being gargbage collected when the app closes. Difficult to say for sure without seeing the code. -- View this message in context: http://forum.world.st/Persistence-of-data-across-sessions-tp3787836p3792618… Sent from the Pharo Smalltalk Users mailing list archive at Nabble.com.

Sept. 6, 2011

[COTDC] 80 - CategoryEnvironment

by laurent laffont

Today: CategoryEnvironment Comment Of The Day Contest - One Day One Comment Rules: #1: Each day a not commented class is elected. Each day the best comment will be integrated with name of the author(s). #2: If you cannot comment it, deprecate it. Results: http://code.google.com/p/pharo/wiki/CommentOfTheDayContest Laurent

Sept. 5, 2011

Re: [Pharo-users] Status of crypto libraries for Pharo?

by Paul DeBruicker

On 09/05/2011 06:02 AM, pharo-users-request(a)lists.gforge.inria.fr wrote: > Date: Sun, 4 Sep 2011 22:27:16 +0200 > From: Geoffroy Couprie<geo.couprie(a)gmail.com> > Subject: Re: [Pharo-users] Status of crypto libraries for Pharo? > To: A friendly place where any question about pharo is welcome > <pharo-users(a)lists.gforge.inria.fr> > Message-ID: > <CAAi8dZyjrrOoi0hRHWjqoa_R5g11GNGOTuX2DSWMO85Cdkb5vg(a)mail.gmail.com> > Content-Type: text/plain; charset=UTF-8 > > IIRC, there's a Smalltalk AES implementation somewhere (I don't know > if it's efficient though). > MD5 and SHA1/SHA2 are there and rapid enough, but storing password > hashes using these algorithms is a very bad practice. You should use > key derivation functions like scrypt and bcrypt. There's no > implementation of these in Smalltalk, so you should wrap their libs in > a plugin. I made something that accesses the standard crypt(3) and libxcrypt libraries with FFI. I've only used it on linux. I have made a Gemstone port. The package is named PasswordHashingFFI and is in the Cryptography repository on squeaksource here: http://www.squeaksource.com/Cryptography With them you can do md5, DES, sha256, sha512, and bcrypt. The Cryptography repository has native implementations of md5, DES, sha256, sha512. I don't know about the security implications of using FFI vs. native vs. a plugin.

Sept. 5, 2011

Re: [Pharo-users] Status of crypto libraries for Pharo?

by Geoffroy Couprie

IIRC, there's a Smalltalk AES implementation somewhere (I don't know if it's efficient though). MD5 and SHA1/SHA2 are there and rapid enough, but storing password hashes using these algorithms is a very bad practice. You should use key derivation functions like scrypt and bcrypt. There's no implementation of these in Smalltalk, so you should wrap their libs in a plugin. On 9/4/11, Larry White <ljw1001(a)gmail.com> wrote: > Hi, > > I'd seen some mail in the archives saying that the old, Smalltalk native > encryption libraries were abandoned and new libraries should wrap some > standard implementation. > > I'm looking at the moment for symmetric algorithms and an md5 hash for > storing passwords. Does anybody know the status of these things? > > Thanks much. > > Larry >

Sept. 4, 2011

Status of crypto libraries for Pharo?

by Larry White

Hi, I'd seen some mail in the archives saying that the old, Smalltalk native encryption libraries were abandoned and new libraries should wrap some standard implementation. I'm looking at the moment for symmetric algorithms and an md5 hash for storing passwords. Does anybody know the status of these things? Thanks much. Larry

Sept. 4, 2011

Persistence of data across sessions

by graham telfer

Hi there, I completed the Bank Account tutorial written for Squeak. It worked fine but I have a question about persistence of data. After I built the bank account and gave it a balance history I saved and quit. Later I wanted to go back to it. The account and its details were gone and I could only create a new account. How is data saved across sessions in Pharo?

Sept. 3, 2011

[COTDC] 79 - RefactoryChange

by laurent laffont

A comment per day is known to expend your life expectancy. Today: RefactoryChange Comment Of The Day Contest - One Day One Comment Rules: #1: Each day a not commented class is elected. Each day the best comment will be integrated with name of the author(s). #2: If you cannot comment it, deprecate it. Results: http://code.google.com/p/pharo/wiki/CommentOfTheDayContest Laurent

Sept. 2, 2011