diff --git a/cloud/google/gcp/compute/computeengine/mode/discovery.pm b/cloud/google/gcp/compute/computeengine/mode/discovery.pm
new file mode 100644
index 000000000..0be13a025
--- /dev/null
+++ b/cloud/google/gcp/compute/computeengine/mode/discovery.pm
@@ -0,0 +1,118 @@
+#
+# Copyright 2020 Centreon (http://www.centreon.com/)
+#
+# Centreon is a full-fledged industry-strength solution that meets
+# the needs in IT infrastructure and application monitoring for
+# service performance.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+package cloud::google::gcp::compute::computeengine::mode::discovery;
+
+use base qw(centreon::plugins::mode);
+
+use strict;
+use warnings;
+use JSON::XS;
+
+sub new {
+    my ($class, %options) = @_;
+    my $self = $class->SUPER::new(package => __PACKAGE__, %options);
+    bless $self, $class;
+
+    $options{options}->add_options(arguments => {
+        'prettify'      => { name => 'prettify' }
+    });
+
+    return $self;
+}
+
+sub check_options {
+    my ($self, %options) = @_;
+    $self->SUPER::init(%options);
+}
+
+sub run {
+    my ($self, %options) = @_;
+
+    my $disco_data;
+    my $disco_stats;
+
+    $disco_stats->{start_time} = time();
+
+    my $instances = $options{custom}->gcp_list_compute_engine_instances();
+    foreach my $instance (@$instances) {
+        my $item = {};
+        $item->{id} = $instance->{id};
+        $item->{name} = $instance->{name};
+        $item->{description} = $instance->{description};
+        $item->{status} = $instance->{status};
+        $item->{cpu_platform} = $instance->{cpuPlatform};
+        if ($instance->{machineType} =~ /machineTypes\/(.*?)$/) {
+            $item->{machine_type} = $1;
+        }
+        if ($instance->{zone} =~ /zones\/(.*?)$/) {
+            $item->{zone} = $1;
+        }
+        $item->{network_interfaces} = [];
+        foreach (@{$instance->{networkInterfaces}}) {
+            push @{$item->{network_interfaces}}, { name => $_->{name}, ip => $_->{networkIP} };
+        }
+        $item->{tags} = [];
+        if (defined($instance->{tags}->{items})) {
+            push @{$item->{tags}}, @{$instance->{tags}->{items}};
+        }
+
+        push @$disco_data, $item;
+    }
+
+    $disco_stats->{end_time} = time();
+    $disco_stats->{duration} = $disco_stats->{end_time} - $disco_stats->{start_time};
+    $disco_stats->{discovered_items} = scalar(@$disco_data);
+    $disco_stats->{results} = $disco_data;
+
+    my $encoded_data;
+    eval {
+        if (defined($self->{option_results}->{prettify})) {
+            $encoded_data = JSON::XS->new->utf8->pretty->encode($disco_stats);
+        } else {
+            $encoded_data = JSON::XS->new->utf8->encode($disco_stats);
+        }
+    };
+    if ($@) {
+        $encoded_data = '{"code":"encode_error","message":"Cannot encode discovered data into JSON format"}';
+    }
+
+    $self->{output}->output_add(short_msg => $encoded_data);
+    $self->{output}->display(nolabel => 1, force_ignore_perfdata => 1);
+    $self->{output}->exit();
+}
+
+1;
+
+__END__
+
+=head1 MODE
+
+Compute engine discovery.
+
+=over 8
+
+=item B<--prettify>
+
+Prettify JSON output.
+
+=back
+
+=cut
diff --git a/cloud/google/gcp/compute/computeengine/plugin.pm b/cloud/google/gcp/compute/computeengine/plugin.pm
index ce2d21871..d7a4427df 100644
--- a/cloud/google/gcp/compute/computeengine/plugin.pm
+++ b/cloud/google/gcp/compute/computeengine/plugin.pm
@@ -31,9 +31,10 @@ sub new {
 
     $self->{version} = '0.1';
     $self->{modes} = {
-        'cpu'     => 'cloud::google::gcp::compute::computeengine::mode::cpu',
-        'diskio'  => 'cloud::google::gcp::compute::computeengine::mode::diskio',
-        'network' => 'cloud::google::gcp::compute::computeengine::mode::network'
+        'cpu'       => 'cloud::google::gcp::compute::computeengine::mode::cpu',
+        'discovery' => 'cloud::google::gcp::compute::computeengine::mode::discovery',
+        'diskio'    => 'cloud::google::gcp::compute::computeengine::mode::diskio',
+        'network'   => 'cloud::google::gcp::compute::computeengine::mode::network'
     };
 
     $self->{custom_modes}->{api} = 'cloud::google::gcp::custom::api';
diff --git a/cloud/google/gcp/custom/api.pm b/cloud/google/gcp/custom/api.pm
index 248dc58df..143695caf 100644
--- a/cloud/google/gcp/custom/api.pm
+++ b/cloud/google/gcp/custom/api.pm
@@ -112,7 +112,7 @@ sub settings {
 sub get_access_token {
     my ($self, %options) = @_;
 
-    my $has_cache_file = $options{statefile}->read(statefile => 'gcp_api_' . md5_hex($self->{key_file}));
+    my $has_cache_file = $options{statefile}->read(statefile => 'gcp_api_' . md5_hex($self->{key_file} . ':' . $self->{authorization_endpoint}));
     my $expires_on = $options{statefile}->get(name => 'expires_on');
     my $access_token = $options{statefile}->get(name => 'access_token');
 
@@ -376,6 +376,90 @@ sub gcp_get_metrics {
     return $results;
 }
 
+sub request_api_paginate {
+    my ($self, %options) = @_;
+
+    my $items = [];
+    my $get_param;
+    $get_param = $options{get_param} if (defined$options{get_param});
+    while (1) {
+        my $response = $self->request_api(
+            method => 'GET',
+            full_url => $options{url},
+            hostname => '',
+            get_param => $get_param
+        );
+        last if (!defined($response->{items}));
+        push @$items, @{$response->{items}};
+
+        last if (!defined($response->{nextPageToken}));
+        $get_param = [@{$options{get_param}}, 'pageToken=' . $response->{nextPageToken}];
+    }
+
+    return $items;
+}
+
+sub gcp_compute_engine_set_base_url {
+    my ($self, %options) = @_;
+
+    my $project_id = $self->get_project_id();
+    my $url = 'https://compute.googleapis.com/compute/v1/projects/' . $project_id;
+    return $url;
+}
+
+sub gcp_list_compute_engine_zones {
+    my ($self, %options) = @_;
+
+    my $url = $self->gcp_compute_engine_set_base_url();
+    my $zones = $self->request_api_paginate(
+        url => $url . '/zones'
+    );
+    return $zones;
+}
+
+sub gcp_list_compute_engine_instances {
+    my ($self, %options) = @_;
+
+    my $results = [];
+    my $url = $self->gcp_compute_engine_set_base_url();
+    my $zones = $self->gcp_list_compute_engine_zones();
+    foreach (@$zones) {
+        my $instances = $self->request_api_paginate(
+            url => $url . '/zones/' . $_->{name} . '/instances'
+        );
+        push @$results, @$instances;
+    }
+    return $results;
+}
+
+sub gcp_cloudsql_set_base_url {
+    my ($self, %options) = @_;
+
+    my $project_id = $self->get_project_id();
+    my $url = 'https://sqladmin.googleapis.com/sql/v1beta4/projects/' . $project_id;
+    return $url;
+}
+
+sub gcp_list_cloudsql_instances {
+    my ($self, %options) = @_;
+
+    my $url = $self->gcp_cloudsql_set_base_url();
+    my $instances = $self->request_api_paginate(
+        url => $url . '/instances'
+    );
+    return $instances;
+}
+
+sub gcp_list_storage_buckets {
+    my ($self, %options) = @_;
+
+    my $buckets = $self->request_api_paginate(
+        url => 'https://storage.googleapis.com/storage/v1/b',
+        get_param => ['project=' . $self->get_project_id()]
+    );
+    return $buckets;
+}
+
 1;
 
 __END__
@@ -408,7 +492,7 @@ Set GCP monitoring endpoint URL (Default: 'https://monitoring.googleapis.com/v3'
 
 =item B<--scope-endpoint>
 
-Set GCP scope endpoint URL (Default: 'https://www.googleapis.com/auth/monitoring.read')
+Set GCP scope endpoint URL (Default: 'https://www.googleapis.com/auth/cloud-platform')
 
 =item B<--zeroed>
 
diff --git a/cloud/google/gcp/database/mysql/mode/discovery.pm b/cloud/google/gcp/database/mysql/mode/discovery.pm
new file mode 100644
index 000000000..479d0e629
--- /dev/null
+++ b/cloud/google/gcp/database/mysql/mode/discovery.pm
@@ -0,0 +1,109 @@
+#
+# Copyright 2020 Centreon (http://www.centreon.com/)
+#
+# Centreon is a full-fledged industry-strength solution that meets
+# the needs in IT infrastructure and application monitoring for
+# service performance.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+package cloud::google::gcp::database::mysql::mode::discovery;
+
+use base qw(centreon::plugins::mode);
+
+use strict;
+use warnings;
+use JSON::XS;
+
+sub new {
+    my ($class, %options) = @_;
+    my $self = $class->SUPER::new(package => __PACKAGE__, %options);
+    bless $self, $class;
+
+    $options{options}->add_options(arguments => {
+        'prettify' => { name => 'prettify' }
+    });
+
+    return $self;
+}
+
+sub check_options {
+    my ($self, %options) = @_;
+    $self->SUPER::init(%options);
+}
+
+sub run {
+    my ($self, %options) = @_;
+
+    my $disco_data;
+    my $disco_stats;
+
+    $disco_stats->{start_time} = time();
+
+    my $instances = $options{custom}->gcp_list_cloudsql_instances();
+    foreach my $instance (@$instances) {
+        next if ($instance->{databaseVersion} !~ /mysql/i);
+        my $item = {};
+        $item->{name} = $instance->{name};
+        $item->{version} = $instance->{databaseVersion};
+        $item->{state} = $instance->{state};
+        $item->{region} = $instance->{region};
+        $item->{tier} = $instance->{settings}->{tier};
+        $item->{instance_type} = $instance->{settings}->{instance_type};
+        $item->{ip_addresses} = [];
+        foreach (@{$instance->{ipAddresses}}) {
+            push @{$item->{ip_addresses}}, { ip_address => $_->{ipAddress}, type => $_->{type} };
+        }
+        push @$disco_data, $item;
+    }
+
+    $disco_stats->{end_time} = time();
+    $disco_stats->{duration} = $disco_stats->{end_time} - $disco_stats->{start_time};
+    $disco_stats->{discovered_items} = scalar(@$disco_data);
+    $disco_stats->{results} = $disco_data;
+
+    my $encoded_data;
+    eval {
+        if (defined($self->{option_results}->{prettify})) {
+            $encoded_data = JSON::XS->new->utf8->pretty->encode($disco_stats);
+        } else {
+            $encoded_data = JSON::XS->new->utf8->encode($disco_stats);
+        }
+    };
+    if ($@) {
+        $encoded_data = '{"code":"encode_error","message":"Cannot encode discovered data into JSON format"}';
+    }
+
+    $self->{output}->output_add(short_msg => $encoded_data);
+    $self->{output}->display(nolabel => 1, force_ignore_perfdata => 1);
+    $self->{output}->exit();
+}
+
+1;
+
+__END__
+
+=head1 MODE
+
+MySQL instance discovery.
+
+=over 8
+
+=item B<--prettify>
+
+Prettify JSON output.
+
+=back
+
+=cut
diff --git a/cloud/google/gcp/database/mysql/plugin.pm b/cloud/google/gcp/database/mysql/plugin.pm
index 8fb7b8f8e..916494045 100644
--- a/cloud/google/gcp/database/mysql/plugin.pm
+++ b/cloud/google/gcp/database/mysql/plugin.pm
@@ -31,11 +31,12 @@ sub new {
 
     $self->{version} = '0.1';
     $self->{modes} = {
-        'cpu'     => 'cloud::google::gcp::database::common::mode::cpu',
-        'innodb'  => 'cloud::google::gcp::database::mysql::mode::innodb',
-        'network' => 'cloud::google::gcp::database::common::mode::network',
-        'queries' => 'cloud::google::gcp::database::mysql::mode::queries',
-        'storage' => 'cloud::google::gcp::database::common::mode::storage'
+        'cpu'       => 'cloud::google::gcp::database::common::mode::cpu',
+        'discovery' => 'cloud::google::gcp::database::mysql::mode::discovery',
+        'innodb'    => 'cloud::google::gcp::database::mysql::mode::innodb',
+        'network'   => 'cloud::google::gcp::database::common::mode::network',
+        'queries'   => 'cloud::google::gcp::database::mysql::mode::queries',
+        'storage'   => 'cloud::google::gcp::database::common::mode::storage'
     };
 
     $self->{custom_modes}->{api} = 'cloud::google::gcp::custom::api';
diff --git a/cloud/google/gcp/storage/mode/discovery.pm b/cloud/google/gcp/storage/mode/discovery.pm
new file mode 100644
index 000000000..3198128b5
--- /dev/null
+++ b/cloud/google/gcp/storage/mode/discovery.pm
@@ -0,0 +1,105 @@
+#
+# Copyright 2020 Centreon (http://www.centreon.com/)
+#
+# Centreon is a full-fledged industry-strength solution that meets
+# the needs in IT infrastructure and application monitoring for
+# service performance.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+package cloud::google::gcp::storage::mode::discovery;
+
+use base qw(centreon::plugins::mode);
+
+use strict;
+use warnings;
+use JSON::XS;
+
+sub new {
+    my ($class, %options) = @_;
+    my $self = $class->SUPER::new(package => __PACKAGE__, %options);
+    bless $self, $class;
+
+    $options{options}->add_options(arguments => {
+        'prettify'      => { name => 'prettify' }
+    });
+
+    return $self;
+}
+
+sub check_options {
+    my ($self, %options) = @_;
+    $self->SUPER::init(%options);
+}
+
+sub run {
+    my ($self, %options) = @_;
+
+    my $disco_data;
+    my $disco_stats;
+
+    $disco_stats->{start_time} = time();
+
+    my $buckets = $options{custom}->gcp_list_storage_buckets();
+    foreach my $bucket (@$buckets) {
+        my $item = {};
+        $item->{id} = $bucket->{id};
+        $item->{name} = $bucket->{name};
+        $item->{project_number} = $bucket->{projectNumber};
+        $item->{location} = $bucket->{location};
+        $item->{location_type} = $bucket->{locationType};
+        $item->{storage_class} = $bucket->{storageClass};
+
+        push @$disco_data, $item;
+    }
+
+    $disco_stats->{end_time} = time();
+    $disco_stats->{duration} = $disco_stats->{end_time} - $disco_stats->{start_time};
+    $disco_stats->{discovered_items} = scalar(@$disco_data);
+    $disco_stats->{results} = $disco_data;
+
+    my $encoded_data;
+    eval {
+        if (defined($self->{option_results}->{prettify})) {
+            $encoded_data = JSON::XS->new->utf8->pretty->encode($disco_stats);
+        } else {
+            $encoded_data = JSON::XS->new->utf8->encode($disco_stats);
+        }
+    };
+    if ($@) {
+        $encoded_data = '{"code":"encode_error","message":"Cannot encode discovered data into JSON format"}';
+    }
+
+    $self->{output}->output_add(short_msg => $encoded_data);
+    $self->{output}->display(nolabel => 1, force_ignore_perfdata => 1);
+    $self->{output}->exit();
+}
+
+1;
+
+__END__
+
+=head1 MODE
+
+Storage discovery.
+
+=over 8
+
+=item B<--prettify>
+
+Prettify JSON output.
+
+=back
+
+=cut
diff --git a/cloud/google/gcp/storage/plugin.pm b/cloud/google/gcp/storage/plugin.pm
index 5117752aa..5a98e4293 100644
--- a/cloud/google/gcp/storage/plugin.pm
+++ b/cloud/google/gcp/storage/plugin.pm
@@ -31,7 +31,8 @@ sub new {
 
     $self->{version} = '0.1';
     $self->{modes} = {
-        'bucket'  => 'cloud::google::gcp::storage::mode::bucket'
+        'bucket'    => 'cloud::google::gcp::storage::mode::bucket',
+        'discovery' => 'cloud::google::gcp::storage::mode::discovery'
     };
 
     $self->{custom_modes}->{api} = 'cloud::google::gcp::custom::api';