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Archive for June 16th, 2021

GitHub – jjjake/internetarchive: A Python and Command-Line Interface to Archive.org

Posted by jpluimers on 2021/06/16

On my list of things to play with: [WayBack] GitHub – jjjake/internetarchive: A Python and Command-Line Interface to Archive.org.

Via:

Related:

  • [WayBack] The Internet Archive Python Library — Internet Archive item APIs 1.8.5 documentation
  • [WayBack] Command-Line Interface — Internet Archive item APIs 1.8.5 documentation
  • [WayBack] Quickstart — Internet Archive item APIs 1.8.5 documentation, including:

    Configuring

    Certain functionality of the internetarchive Python library requires your archive.org credentials. Your IA-S3 keys are required for uploading, searching, and modifying metadata, and your archive.org logged-in cookies are required for downloading access-restricted content and viewing your task history. To automatically create a config file with your archive.org credentials, you can use the ia command-line tool:

    $ ia configure
    Enter your archive.org credentials below to configure 'ia'.
    
    Email address: user@example.com
    Password:
    
    Config saved to: /home/user/.config/ia.ini
    

    Your config file will be saved to $HOME/.config/ia.ini, or $HOME/.ia if you do not have a .configdirectory in $HOME. Alternatively, you can specify your own path to save the config to via ia --config-file '~/.ia-custom-config' configure.

    If you have a netc file with your archive.org credentials in it, you can simply run ia configure --netrc. Note that Python’s netrc library does not currently support passphrases, or passwords with spaces in them, and therefore not currently suported here.

–jeroen

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Posted in Development, Internet, InternetArchive, Power User, Python, Scripting, Software Development, WayBack machine | Leave a Comment »

ODAC: calling SYS.DBMS_SESSION.SET_NLS failing with ORA-06550/PLS-00103

Posted by jpluimers on 2021/06/16

Do not call SYS.DBMS_SESSION.SET_NLS with an instance of the [Archive.is] TOraStoredProc Class, as under the hood, it will translate the call to this:

Class:Ora.TOraStoredProc;Component:sprSetNls;Flag:tfQPrepare,Text:Prepare: begin
  SYS.DBMS_SESSION.SET_NLS(:PARAM, :VALUE);
end;
:PARAM(VARCHAR[22],IN)='NLS_NUMERIC_CHARACTERS' 
:VALUE(VARCHAR[4],IN)=''.,''

The above is a translation of the bold portions in this call (note it contains the an instantiation of an [Archive.is] TOraSession Class as you need one; examples further down assume this session instance to exist):

var
  MainOraSession: TOraSession;
  DbmsSessionSetNlsOraStoredProc: TOraStoredProc;
begin
  MainOraSession := TOraSession.Create(Self);
  try
    MainOraSession.Name := 'MainOraSession';
    MainOraSession.Username := 'FOO';
    MainOraSession.Server := 'BAR';
    MainOraSession.LoginPrompt := False;
    MainOraSession.Options.UseOCI7 := True;
    MainOraSession.Open();
    DbmsSessionSetNlsOraStoredProc := TOraStoredProc.Create(Self);
    try
      DbmsSessionSetNlsOraStoredProc.Name := 'DbmsSessionSetNlsOraStoredProc';
      DbmsSessionSetNlsOraStoredProc.StoredProcName := 'SYS.DBMS_SESSION.SET_NLS';
      DbmsSessionSetNlsOraStoredProc.Session := MainOraSession;
      DbmsSessionSetNlsOraStoredProc.Debug := True;
      with DbmsSessionSetNlsOraStoredProc.ParamData.Add do 
      begin
        DataType := ftString;
        Name := 'PARAM';
        ParamType := ptInput;
        Value := nil;
      end;
      with DbmsSessionSetNlsOraStoredProc.ParamData.Add do
      begin
        DataType := ftString;
        Name := 'VALUE';
        ParamType := ptInput;
        Value := nil;
      end;
      DbmsSessionSetNlsOraStoredProc.ParamByName('PARAM').AsString := sParam;
      DbmsSessionSetNlsOraStoredProc.ParamByName('VALUE').AsString := sValue;
      DbmsSessionSetNlsOraStoredProc.Prepare();
      DbmsSessionSetNlsOraStoredProc.ExecProc();
    finally
      DbmsSessionSetNlsOraStoredProc.Free();
    end;
  finally
    MainOraSession();
  end;
end;

It will result in an Oracle error during the Prepare of the statement:

ORA-06550: line 2, column 36:
PLS-00103: Encountered the symbol ":" when expecting one of the following:

   ( - + case mod new not null 
   
   continue avg count current exists max min prior sql stddev
   sum variance execute forall merge time timestamp interval
   date  pipe
   

In stead, take your TOraPackage object and make a call like this:

var
  DbmsSessionOraPackage: TOraPackage;
begin
  DbmsSessionOraPackage := TOraPackage.Create(Self);
  try
    DbmsSessionOraPackage.Name := 'DbmsSessionOraPackage';
    DbmsSessionOraPackage.Debug := True;
    DbmsSessionOraPackage.Session := dbSession;
    DbmsSessionOraPackage.PackageName := 'SYS.DBMS_SESSION';

    DbmsSessionOraPackage.ExecProcEx('SET_NLS', ['PARAM', 'NLS_NUMERIC_CHARACTERS', 'VALUE', '''.,''']);
  finally
    DbmsSessionOraPackage.Free();
  end;
end;

This then results in this in the SQL monitoring (note quoting quotes is different in SQL than Delphi):

Class:Ora.TOraSQL;Component:;Flag:tfQExecute,Text:begin
  SYS.DBMS_SESSION.SET_NLS(:PARAM, :VALUE);
end;
:PARAM(VARCHAR[22],IN)='NLS_NUMERIC_CHARACTERS' 
:VALUE(VARCHAR[4],IN)=''.,''

instead of this:

Class:Ora.TOraStoredProc;Component:sprSetNls;Flag:tfQPrepare,Text:Prepare: begin
  SYS.DBMS_SESSION.SET_NLS(:PARAM, :VALUE);
end;
:PARAM(VARCHAR[22],IN)='NLS_NUMERIC_CHARACTERS' 
:VALUE(VARCHAR[4],IN)=''.,''

I am still a sort of baffled why this is a problem. But using the TOraPackage works.

One thing to remember is that an TOraSession instance does not allow you to get to the underlying TOCIConnection instance, which does allow setting NLS information directly; see for instance the old code at [WayBack] OraClasses.pas in xinhaining-dianjianyiqi-tongxunchengxu | source code search engine.

This is because the underlying connection can be both OCI and Direct depending on the TOraSession.Options.Direct value: [WayBack] About Connection.Ping method when Direct Mode – Devart Forums.

Other calls on SYS.DBMS_SESSION succeed

The odd thing is that single-parameter calls on SYS.DBMS_SESSION.SET_ROLE (which can be tricky, see [WayBack] Introducing Database Security for Application Developers) work fine, so no alternative (like a plain [WayBack] SET ROLE) is needed:

var
  DbmsSessionSetRoleOraStoredProc: TOraStoredProc;
begin
  DbmsSessionSetRoleOraStoredProc := TOraStoredProc.Create(Self);
  try
    DbmsSessionSetRoleOraStoredProc.Name := 'DbmsSessionSetRoleOraStoredProc';
    DbmsSessionSetRoleOraStoredProc.StoredProcName := 'SYS.DBMS_SESSION.SET_ROLE';
    DbmsSessionSetRoleOraStoredProc.Session := dbSession;
    with DbmsSessionSetRoleOraStoredProc.ParamData.Add do begin 
      DataType := ftString;
      Name := 'ROLE_CMD';
      ParamType := ptInput;
      Value := 'EXAMPLE';
    end;
    DbmsSessionSetRoleOraStoredProc.ParamByName('ROLE_CMD').AsString := 'EXAMPLEROLE';
    DbmsSessionSetRoleOraStoredProc.Prepare;
    DbmsSessionSetRoleOraStoredProc.ExecProc;
  finally
    DbmsSessionSetRoleOraStoredProc.Free();
  end;
end;

results in this log:

Class:Ora.TOraStoredProc;Component:StrdPSetRole;Flag:tfQExecute,Text:begin
  SYS.DBMS_SESSION.SET_ROLE(:ROLE_CMD);
end;
:ROLE_CMD(VARCHAR[10],IN)='EXAMPLEROLE'

Similar for SYS.DBMS_APPLICATION_INFO

Calling anything on DBMS_APPLICATION_INFO gives you an exception.

On the .NET side of DevArt, you can use

–jeroen

Posted in Database Development, Delphi, Development, OracleDB, Software Development | Leave a Comment »

ODAC undocumented exception ‘Need Oracle 8 Call Interface’

Posted by jpluimers on 2021/06/16

I got this when taking over maintenance of some legacy code that called a stored procedure in a :

---------------------------
Debugger Exception Notification
---------------------------
Project LegacyProject.exe raised exception class Exception with message 'Need Oracle 8 Call Interface'.
---------------------------
Break   Continue   Help   
---------------------------

The problem with finding more information about this, is that there are virtual no hits on Oracle 8 Call Interface, OCI 8 or Oracle Call Interface 8.

A good document is [WayBack] OCI: Introduction and Upgrading (found via [Archive.is] “OCI 7” – Google Search), but it never mentions 8, only these terms occur:

  • release 7.x OCI
  • OCI release 7
  • OCI version 7
  • Oracle release 7 OCI
  • Release 8.0 of the OCI
  • 7.x OCI
  • Later OCI
  • Post-release 7.x OCI

The error happens on the first instance of at least an [Archive.is] TOraStoredProc Class or [Archive.is] TOraPackage Class that prepares or executes a stored procedure.

One problem is that this is an instance of a plain [WayBack] Exception Class , not a [WayBack] EDatabaseError Class or [Archive.is] EDAError Class.

What it means is that the UseOCI7 sub-property was set to True in your TOraSession property Options:

var
  MainOraSession: TOraSession;
begin
  MainOraSession := TOraSession.Create(Self);

  MainOraSession.Name := 'MainOraSession';
  MainOraSession.Username := 'ExammpleUser';
  MainOraSession.Server := 'ExampleTnsName';
  MainOraSession.LoginPrompt := False;
  MainOraSession.Options.UseOCI7 := True;

One thing to remember is that an TOraSession instance does not allow you to get to the underlying TOCIConnection instance, which does allow setting NLS information directly; see for instance the error at [WayBack] Not connected to oracle error – Devart Forums and old code at [WayBack] OraClasses.pas … | source code search engine and [WayBack] Ora.pas in … | source code search engine; UniDac is relatively similar [WayBack] UniDAC v3.7 …:OraClassesUni.pas (another explanation is in [WayBack] Setting the Client Info for the TOraAlerter extra session – Devart Forums).

This is because the underlying connection can be both OCI and Direct depending on the TOraSession.Options.Direct value: [WayBack] About Connection.Ping method when Direct Mode – Devart Forums.

After the first occurrence, you will not get this error again, you get way more spurious errors, especially on stored procedures in packages, where the stored procedure has 2 or more parameters. There you get errors like this one for TOraStoredProc:

ORA-06550: line 2, column 36:
PLS-00103: Encountered the symbol ":" when expecting one of the following:

   ( - + case mod new not null <an identifier>
   <a double-quoted delimited-identifier> <a bind variable>
   continue avg count current exists max min prior sql stddev
   sum variance execute forall merge time timestamp interval
   date <a string literal with character set specification>
   <a number> <a single-quoted SQL string> pipe
   <an alternatively-quoted string literal with character set speci.

When logging using a [Archive.is] TOraSQLMonitor Class instance (use the [Archive.is] TCustomDASQLMonitor.OnSQL Event with the [Archive.is] TOnSQLEvent Procedure Reference signature) you can get the underlying information of the TOraStoredProc (see the example code below that raises this):

Class:Ora.TOraStoredProc;Component:sprSetNls;Flag:tfQPrepare,Text:Prepare: begin
  SYS.DBMS_SESSION.SET_NLS(:PARAM, :VALUE);
end;
:PARAM(VARCHAR[22],IN)='NLS_NUMERIC_CHARACTERS' 
:VALUE(VARCHAR[4],IN)=''.,''

It fails equally when doing any DBMS_APPLICATION_INFO calls, for which the .NET version of ODAC has a special [WayBack] SetDbmsApplicationInfo Method in the [WayBack] OracleConnection Class. Too bad the Delphi version omits that.

When using TOraPackage, you can get different errors, like for instance this EDatabaseError:

Exception class EDatabaseError with message 'Parameter 'VALUE' not found'.

It basically means that through OCI, the parameter list could not be obtained, so the error is caught on the Delphi side instead of the Oracle side.

Using a TOraPackage is easier at design time, as it allows you to select the [Archive.is] TOraPackage.PackageName Property property using the underlying TOraSession. Somehow a TOraStoredProc does not allow you to select the [Archive.is] TOraStoredProc.StoredProcName Property at design time.

Related:

–jeroen

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