如何从 perl 脚本中的文本文件调用 DBI 连接参数？

Question

I'm having a code in which i'm extracting data from table and displaying the O/P.我有一个代码，我在其中从表中提取数据并显示 O/P。 But i want to give connection string from txt file(not hardcoded in script) .但我想从 txt 文件中给出连接字符串（不是硬编码在脚本中）。 Can anyone help how i can provide below values from input file.任何人都可以帮助我如何从输入文件中提供以下值。

$dbh = DBI->connect( 'dbi:Oracle:DB_INST',"USER","PASS")
    or die "Database connection not made: $DBI::errstr";

My code:我的代码：

#!/usr/bin/perl
$ENV{ORACLE_HOME}='/ora/11.2.0.3';
$LD_LIBRARY_PATH='/ora/11.2.0.3/lib';
use Shell;
use DBI ;
use CGI ;
my $cgi = new CGI;
print $cgi->header;
my $dbh;
$CGI_ST = new CGI;
#################### FUNCTIONS DECLARATION ########################################################
sub Start_HTM
{
        print "<html>\n\n";
        print "<title>LOGICAL DATE CHECK</title>\n\n";
        print "<body>\n<center>\n";
        print "<hr><h1 align=center><font color=#FFA500><u>LOGICAL DATE CHECK</u></font></h1>\n";
}
sub End_HTM
{
        print "<a href=\"#\" onClick=window.close()>Close Window</a></b></small>";
        print "</center>\n</body>\n</html>";
}
sub DisBackButton
{
        print "<br><br><br><INPUT TYPE=button value=Back onClick=history.back()>";
}
####################################################################################################
print "Content-type: text/html\n\n";
open (FILE,"header.asp");
my $file = <FILE>;
close(FILE);
print "$file";
print "<SCRIPT LANGUAGE=JavaScript>";
print "</script>";
my $environment=$CGI_ST->param("environment");
my $product=$CGI_ST->param("product");
Start_HTM();
if ( "$product" eq "2" && "$environment" eq "MPET" ) {
print $cgi->start_html(-title=>'Basic CGI');
# you should change the connect method call to use the DBD you are
# using. The following examples all use DBD::ODBC and hence the
# first argument to the connect method is 'dbi:ODBC:DSN'.
my $dsn = "DBI:Oracle:$db_inst";
$dbh = DBI->connect( 'dbi:Oracle:DB_INST',"USER","PASS") or die "Database connection not made: $DBI::errstr";
my $sql = qq{SELECT logical_date,logical_date_type from logical_date where expiration_date is null };
my $sth = $dbh->prepare( $sql ) || die $dbh->errstr;
$sth->execute() || die $dbh->errstr;
print $cgi->table( { -border=>"1" } );
 while (@data = $sth->fetchrow_array()) {
 $Logical_Date_O = $data[0];
 $Logical_Date_B = $data[1];
 $Logical_Date_R = $data[2];
print "<tr><td><font color='black'>$Logical_Date_O</font></td>
<td>$Logical_Date_B</td><td>$Logical_Date_R</td></tr>\n";
}
} 
print $cgi->end_table;
print $cgi->end_html;

Answer 1

You want to parse database credentials from properties file instead of hard coding it.您想从属性文件中解析数据库凭据，而不是对其进行硬编码。 Create ini file and enter credentials into them and then use Config::IniFiles to extract value out of them.创建ini文件并在其中输入凭据，然后使用Config::IniFiles从中提取值。

Then, You can pass those values to DBI and connect to database.然后，您可以将这些值传递给DBI并连接到数据库。

my $cfg = Config::IniFiles -> new( -file => 'path/config/database_config.ini' );

my $dbinst = $cfg -> val( 'DATABASE', 'DBINST' );
my $dbuser = $cfg -> val( 'DATABASE', 'DBUSER' );
my $dbpass = $cfg -> val( 'DATABASE', 'DBPASS' );

my $dbh = DBI->connect( "dbi:Oracle:$dbinst", $dbuser, $dbpass)
    or die "Database connection not made: $DBI::errstr";

Here is config file:这是配置文件：

[DATABASE]
  # DB string
  DBINST=XXX
  # database username
  DBUSER=XXX
  # database password
  DBPASS=XXX

Answer 2

Create a file database.conf and you can write it in any format CSV, XLS or simple delimited Flat file so that you can easily parse it.创建一个文件database.conf，您可以将其写入任何格式的CSV、XLS 或简单的分隔平面文件，以便您可以轻松解析它。 I'm considering a format where I'm using '=' as a separator.我正在考虑使用 '=' 作为分隔符的格式。

# filename database.conf
HOST=dbi:Oracle:DB_INST
USER=USER,
PASSWORD=PASS

Now in your perl script use following code for retrieving it:现在在您的 perl 脚本中使用以下代码来检索它：

my $db_conf_file = 'database.conf';
my $delimiter = '='; # You can change the delimiter accordingly
my %db;

open(my $FH, '<', $db_conf_file) or die "Could not open $db_conf_file";

while(my $line = <$FH>){
  chomp $line;
  my @fields = split $delimiter , $line;
  $db->{$fields[0]} = $fields[1];
}

close($FH);

$dbh = DBI->connect($db->{HOST}, $db->{USER},$DB->{PASSWORD})
  or die "Database connection not made: $DBI::errstr";
..............

Answer 3

You already have code that reads data from a file:您已经有了从文件中读取数据的代码：

open (FILE,"header.asp");
my $file = <FILE>;
close(FILE);

So I'm not really sure what problem you are having.所以我不确定你遇到了什么问题。

Let's assume that you put the details in a file called credentials.txt which looks like this like this:假设您将详细信息放在一个名为 credentials.txt 的文件中，该文件如下所示：

Oracle:DB_INST:USER:PASS

You could then write a subroutine called get_credentials() which looks like this:然后，您可以编写一个名为get_credentials()的子例程，如下所示：

sub get_credentials {
  my $cred_file = 'credentials.txt';
  open my $cred_fh, '<', $cred_file
    or die "Can't open $cred_file: $!\n"

  my $data = <$cred_fh>;
  chomp $data;
  return split /:/, $data;
}

You would then call it like this:然后你会这样称呼它：

my ($type, $instance, $user, $pass) = get_credentials();
my $dbh = DBI->connect( "dbi:$type:$instance", $user, $pass)
  or die "Database connection not made: $DBI::errstr";

A few other comments on your code.关于您的代码的其他一些评论。

Always include use strict and use warnings in your code.始终在代码中包含use strict和use warnings 。
Why use Shell ?为什么use Shell ？ I don't think you use it?我不认为你使用它？
You create two CGI objects ( $cgi and $CGI_ST ).您创建了两个 CGI 对象（ $cgi和$CGI_ST ）。 You only need one.你只需要一个。
We've known since the last millennium that putting raw HTML inside your Perl code is a terrible idea.自上个千年以来，我们就知道将原始 HTML 放入 Perl 代码中是一个糟糕的主意。 Look at using templates to separate HTML from Perl.看看使用模板将 HTML 与 Perl 分开。
You print two CGI headers ( print $cgi->header and print "Content-type: text/html\\n\\n" . That's one too many.您打印两个 CGI 标题（ print $cgi->header并print "Content-type: text/html\\n\\n" 。这太多了。
Always check the return value from open() ( open (FILE,"header.asp") or die ... )始终检查open()的返回值（ open (FILE,"header.asp") or die ... ）
Use the three-arg version of open() and lexical filehandles ( open (my $fh, '<', 'header.asp') or die ... ).使用open()和词法文件句柄的三参数版本（ open (my $fh, '<', 'header.asp') or die ... ）。
Don't quote variables unnecessarily ( print "$file" is better written print $file and if ( "$product" eq "2" && "$environment" eq "MPET" ) is better written if ( $product eq "2" && $environment eq "MPET" ) .不要不必要地引用变量（ print "$file"最好写成print $file并且if ( "$product" eq "2" && "$environment" eq "MPET" )最好写if ( $product eq "2" && $environment eq "MPET" ) 。
I think you mean $cgi->start_table() , not $cgi->table() .我想你的意思是$cgi->start_table() ，而不是$cgi->table() 。 But the HTML generation functions have been deprecated .但是HTML 生成功能已被弃用。 Please don't use them.请不要使用它们。

Finally, and most importantly, CGI is old technology.最后，也是最重要的，CGI 是一种古老的技术。 Please read CGI::Alternatives and switch to a modern technology that is based on PSGI.请阅读CGI::Alternatives并切换到基于 PSGI 的现代技术。

如何从 perl 脚本中的文本文件调用 DBI 连接参数？

问题描述

3 个解决方案

解决方案1
1 2017-01-17 06:36:52

解决方案2
0 2017-01-17 06:49:00

解决方案3
0 2017-01-18 07:23:19

如何从 perl 脚本中的文本文件调用 DBI 连接参数？

问题描述

3 个解决方案

解决方案1 1 2017-01-17 06:36:52

解决方案2 0 2017-01-17 06:49:00

解决方案3 0 2017-01-18 07:23:19

解决方案1
1 2017-01-17 06:36:52

解决方案2
0 2017-01-17 06:49:00

解决方案3
0 2017-01-18 07:23:19