in reply to Re: Paws result how to process?
in thread Paws result how to process?

I must be missing something....

Thanks again for the help!

below is the dump from Data::Dumper

and the modified function produces these errors....

ERRORS: Scalar found where operator expected at ./describe_alarms.pl line 97, +near "@($result" (#1) (S syntax) The Perl lexer knows whether to expect a term or an ope +rator. If it sees what it knows to be a term when it was expecting to see + an operator, it gives you this warning. Usually it indicates that an operator or delimiter was omitted, such as a semicolon. (Missing operator before $result?) (#2) (S syntax) This is an educated guess made in conjunction with the +message "%s found where operator expected". Often the missing operator is + a comma. syntax error at ./describe_alarms.pl line 97, near "@($result" Execution of ./describe_alarms.pl aborted due to compilation errors (# +3) (F) Probably means you had a syntax error. Common reasons include +: A keyword is misspelled. A semicolon is missing. A comma is missing. An opening or closing parenthesis is missing. An opening or closing brace is missing. A closing quote is missing. Often there will be another error message associated with the synt +ax error giving more information. (Sometimes it helps to turn on -w. +) The error message itself often tells you where it was in the line +when it decided to give up. Sometimes the actual error is several toke +ns before this, because Perl is good at understanding random input. Occasionally the line number may be misleading, and once in a blue + moon the only way to figure out what's triggering the error is to call perl -c repeatedly, chopping away half the program each time to se +e if the error went away. Sort of the cybernetic version of 20 ques +tions. Uncaught exception from user code: syntax error at ./describe_alarms.pl line 97, near "@($result" Execution of ./describe_alarms.pl aborted due to compilation error +s.
MODIFIED FUNCTION: sub describe_alarms { my ($alarm_name_prefix) = @_; my $result; my $obj = Paws->service( 'CloudWatch', region => 'us-east-1' ); $result = $obj->DescribeAlarms( AlarmNamePrefix => $alarm_name_prefix, ); # print Dumper($result); print Dumper(ref @($result->MetricAlarms)); #print Dumper(@($result->MetricAlarms)); exit; =pod foreach ( @($result->MetricAlarms) ){ print "-"x79,"\n"; print "**AlarmName** : ", $_->AlarmName,"\n"; print Dumper($_); } print "\n***\n--number of elements: ", scalar @($result->MetricAla +rms), "\n"; #return $result; =cut return $result; }
DUMP: $VAR1 = bless( { '_request_id' => '3eeadc30-9588-11e8-9cf2-e1b5a579da44', 'MetricAlarms' => [ bless( { 'AlarmArn' => 'arn:aws:cloudwatch:us-east-1:xxxxxxxxxxxxx:alarm:pubtech-best-gte-90- +dev', 'StateReason' => 'Threshold Crossed: 1 out of the last 2 datapoints [0.152614819450015 +(01/08/18 11:31:00)] was not greater than or equal to the threshold ( +90.0) (minimum 1 datapoint for ALARM -> OK transition).', 'AlarmActions' => [ 'arn:aws:sns:us-east-1:xxxxxxxx:bestsellers_prd_best-alarm2' ], 'AlarmName' => 'pubtech-best-gte-90-dev', 'AlarmDescription' => 'Alarm when volume is greater than or equal 90 p +ercent', 'Period' => '300', 'ActionsEnabled' => 1, 'Dimensions' => [ bless( { 'Name' => 'Filesystem', 'Value' => '/dev/xvdf' }, 'Paws::CloudWatch::Dimension' ), bless( { 'Name' => 'MountPath', 'Value' => '/best' }, 'Paws::CloudWatch::Dimension' ), bless( { 'Value' => 'xxxxxxxxxxxxxxx', 'Name' => 'InstanceId' }, 'Paws::CloudWatch::Dimension' ) ], 'Statistic' => 'Average', 'Threshold' => '90.0', 'DatapointsToAlarm' => '2', 'Namespace' => 'System/Linux', 'ComparisonOperator' => 'GreaterThanOrEqualToThres +hold', 'StateReasonData' => '{"version":"1.0","queryDate":"2018-08-01T11:36:17.049+0000","startDat +e":"2018-08-01T11:31:00.000+0000","statistic":"Average","period":300, +"recentDatapoints":[0.152614819450015],"threshold":90.0}', 'StateValue' => 'OK', 'StateUpdatedTimestamp' => '2018-08-01T11:36:17.06 +2Z', 'EvaluationPeriods' => '2', 'TreatMissingData' => 'missing', 'MetricName' => 'DiskSpaceUtilization', 'AlarmConfigurationUpdatedTimestamp' => '2018-07-12T14:40:07.798Z' }, 'Paws::CloudWatch::MetricAlarm' ) ] }, 'Paws::CloudWatch::DescribeAlarmsOutput' );

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Re^3: Paws result how to process?
by Lotus1 (Vicar) on Aug 01, 2018 at 15:19 UTC

    It was untested code so I messed up the brackets to the right of '@'. It needs to be curly braces '{}' in that case.

    foreach( @{$result->MetricAlarms} ){ print "-"x79,"\n"; print "**AlarmName** : ", $_->AlarmName,"\n"; print Dumper($_); } print "\n***\n--number of elements: ", scalar @{$result->MetricAla +rms}, "\n";

    Alternatively you can use an intermediate variable to hold the array ref before de-referencing it.

    my $ar_ref = $result->MetricAlarms; foreach( @$ar_ref ){ ...

    This article shows how to use the curly braces for dereferencing things. Also have a look at this node and this article in the Perl docs.

      I had replaced curly braces, but still didn't seem to work, but it does now!!

      Thanks Again!