servicenow_cmdb_integration

pdk
tasks
A module that allows Puppet to query ServiceNow's CMDB for node data, including classification.
Puppet

Puppet

puppetlabs

2,036 downloads

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Version information

  • 0.2.0 (latest)
  • 0.1.0
released Jul 29th 2020
This version is compatible with:
  • Puppet Enterprise 2019.8.x, 2019.7.x, 2019.5.x, 2019.4.x
  • Puppet >= 6.14.0 < 7.0.0
  • CentOS
    ,
    OracleLinux
    ,
    RedHat
    ,
    Scientific
    ,
    Ubuntu
    ,
    SLES
Tasks:
  • add_environment_rule

Start using this module

Documentation

puppetlabs/servicenow_cmdb_integration — version 0.2.0 Jul 29th 2020

servicenow_cmdb_integration

Table of Contents

  1. Description
  2. Setup - The basics of getting started with servicenow_cmdb_integration
  3. Development - Guide for contributing to the module

Description

This module integrates ServiceNow's CMDB with Puppet Enterprise. Specifically, it lets you

  • Access a node's CMDB record as trusted external data via the trusted.external.servicenow hash.

  • Classify nodes in the CMDB by using it to store the node's Puppet environment and classes. Puppet will automatically fetch and apply this classification in the node's subsequent runs.

Setup

What servicenow_cmdb_integration affects

  • Installs a servicenow.rb script into a created /etc/puppetlabs/puppet/trusted-external-commands directory.

  • Creates a servicenow_cmdb.yaml configuration file in /etc/puppetlabs/puppet that is needed by the servicenow.rb script.

  • Updates puppet.conf's trusted_external_command setting to point to the servicenow.rb script.

  • Restarts puppetserver (pe-puppetserver service) so that the puppet.conf changes can take effect

If you'd like to also classify nodes in ServiceNow's CMDB, then the module:

  • Requires adding a rule that matches on a ServiceNow-specified Puppet environment to all of your environment groups

  • Requires adding a new servicenow_cmdb_integration::getvar Hiera backend to all of your environment hiera.yaml files

  • Requires updating all of your environments' site.pp files to include a servicenow_cmdb_integration::classification class

Beginning with servicenow_cmdb_integration

Note: If you're interested in both the ServiceNow CMDB external data and node classification features of this module, then you can just read the classification section since that depends on the CMDB external data feature.

ServiceNow CMDB as trusted external data

Apply the servicenow_cmdb_integration class on all of your compilers. This looks something like:

class { 'servicenow_cmdb_integration':
  instance    => '<fqdn_of_snow_instance>',
  user        => '<user>',
  password    => '<password>',
}

Or if you'd prefer to use an OAuth token:

class { 'servicenow_cmdb_integration':
  instance    => '<fqdn_of_snow_instance>',
  oauth_token => '<snow_oauth_token>',
}

Please note that you may specify a user/password or an oauth token, but not both.

If you're using a hiera-eyaml encrypted password, then make sure that eyaml decrypt -s <encrypted_password> returns the same password on all nodes in the PE Master node group.

For customers using PE 2019.7+, we recommend adding this class to the PE Master node group. If HA is installed, then it should also be added to the PE HA Replica group.

This class installs the servicenow.rb script. The script fetches the node's CMDB record from the cmdb_ci table and stores it in the trusted.external.servicenow variable. This variable is a hash of <field> => <value> where <field> is a field in the cmdb_ci table and <value> is the field's value. If the field's a reference field then <value> is that field's display value.

Note: Puppet invokes the servicenow.rb script via the calling-convention servicenow.rb <certname>. The script fetches the node's CMDB record by querying the record whose fqdn field matches <certname>. If you're storing node certnames in a separate CMDB field, then you can set the certname_field parameter to that CMDB field's column name.

Note to readers from the classification section: If you're already storing the node's environment and classes in your own CMDB fields, then make sure to specify those fields' column names in the environment_field and classes_field parameters, respectively. Otherwise, these default to u_puppet_environment and u_puppet_classes, respectively.

ServiceNow node classification

This section talks about the setup required to classify nodes in ServiceNow's CMDB. Specifically, it walks through how to store the node's Puppet environment and classes in the CMDB and make Puppet aware of that information.

Here's what you have to do.

1. Add the following custom fields to the cmdb_ci table in your ServiceNow instance:

Field Name Column Label Column Name Type
Puppet Environment Puppet Environment u_puppet_environment String (Full UTF-8)
Puppet Classes Puppet Classes u_puppet_classes String (Full UTF-8)

Here, Puppet Classes is a JSON encoding of a Hash[String, Hash[String, Any]] type (informally, a Hash[ClassName, Parameters] object). For example, "{\"foo_class\":{\"foo_param\":\"foo_value\"}}" is a valid value for Puppet Classes. However, {"foo_class":{"foo_param":"foo_value"}} is not.

2. In your control-repo, create a commit that:

  • Adds the following to the Puppetfile:

     mod 'puppetlabs/servicenow_cmdb_integration'
    
  • Adds the following Hiera backend to the hiera.yaml file:

    - name: "ServiceNow Hiera data"
      data_hash: servicenow_cmdb_integration::getvar
      options:
        var: trusted.external.servicenow.hiera_data
    

    This step's necessary for the integration to properly read the class parameters stored in Puppet Classes.

  • Adds a include servicenow_cmdb_integration::classification line to the site.pp file at topscope. You can do this at the bottom of the site.pp file as shown:

    # site.pp
    ...
    include servicenow_cmdb_integration::classification
    

    The classification class includes all the classes specified in trusted.external.servicenow.puppet_classes. If that variable's not defined for the given node, then the class noops.

Once you've created the commit, deploy it to all of your relevant enviroments. Otherwise, classification will not work.

3. For all relevant environments, add a rule of the form ['=', ['trusted', 'external', 'servicenow', 'puppet_environment'], '<enviroment>'] to their corresponding environment group. You can use the PE console to do this or the servicenow_cmdb_integration::add_environment_rule task. If you're using the PE console, then the rule should look something like:

trusted.external.servicenow.puppet_environment = <environment>

If you're using the task, then the task invocation should look something like:

puppet task run servicenow_cmdb_integration::add_environment_rule --params '{"group_names": <array_of_environment_group_names>}' --nodes <fqdn_of_node_containing_classifier_service>

This step's necessary for the integration to set the node's environment to Puppet Environment.

4. Setup the trusted external command by following the instructions in the trusted external data section.

Development

Unit tests

To run the unit tests:

bundle install
bundle exec rake spec

Acceptance tests

The acceptance tests use puppet-litmus in a multi-node fashion. The nodes consist of a 'master' node representing the PE master (and agent), and a 'ServiceNow' node representing the ServiceNow instance. All nodes are stored in a generated inventory.yaml file (relative to the project root) so that they can be used with Bolt.

To setup the test infrastructure, use bundle exec rake acceptance:setup. This will:

  • Provision the master VM
  • Setup PE on the VM
  • Setup the mock ServiceNow instance. This is just a Docker container on the master VM that mimics the relevant ServiceNow endpoints. Its code is contained in spec/support/acceptance/servicenow.
  • Install the module on the master

Each setup step is its own task; acceptance:setup's implementation consists of calling these tasks. Also, all setup tasks are idempotent. That means its safe to run them (and hence acceptance:setup) multiple times.

Note: You can run the tests on a real ServiceNow instance. To do so, make sure that you've extended the cmdb_ci table with the Puppet Classes (field type String), Puppet Environment (field type String), and Puppet Classes NVP (field type Name-Value pair) fields (using the ServiceNow-generated column names for each field). Afterwards, invoke bundle exec rake 'acceptance:setup_servicenow_instance[<fqdn>,<user>,<password>,<oauth_token>]'. This will update the inventory.yaml file with the actual ServiceNow instance credentials. Note that the <oauth_token> is optional; if not provided, then the oauth token tests will be skipped.

To run the tests after setup, you can do bundle exec rspec spec/acceptance. To teardown the infrastructure, do bundle exec rake acceptance:tear_down.

Below is an example acceptance test workflow:

bundle exec rake acceptance:setup
bundle exec rspec spec/acceptance
bundle exec rake acceptance:tear_down

Note: Remember to run bundle exec rake acceptance:install_module whenever you make updates to the module code. This ensures that the tests run against the latest version of the module.

Debugging the acceptance tests

Since the high-level setup is separate from the tests, you should be able to re-run a failed test multiple times via bundle exec rspec spec/acceptance/path/to/test.rb.

Note: Sometimes, the modules in spec/fixtures/modules could be out-of-sync. If you see a weird error related to one of those modules, try running bundle exec rake spec_prep to make sure they're updated.

The file spec/support/acceptance/helpers.rb contains some useful helpers that can ease debugging. Below is an example of how you can use these helpers.

Eniss-MacBook-Pro:puppetlabs-servicenow_cmdb_integration enisinan$ bundle exec irb
irb(main):001:0> load 'spec/support/acceptance/helpers.rb'
=> true
irb(main):002:0> include TargetHelpers
=> Object
irb(main):003:0> # Use Limus' helpers to do stuff on the master
irb(main):004:0> master.run_shell('ls')
=> #<OpenStruct exit_code=0, exit_status=0, stdout="1\nanaconda-ks.cfg\nmanifest_20200622_22980_155zqve.pp\nmanifest_20200622_22980_19g775.pp\nmanifest_20200622_22980_1dtgel2.pp\nmanifest_20200622_22980_1mf16ty.pp\nmanifest_20200622_22980_1nsgok6.pp\nmanifest_20200623_44190_1b2h8rj.pp\nmanifest_20200623_44190_9e5vur.pp\nmanifest_20200623_44190_ks1n4g.pp\nmanifest_20200623_44190_o22v01.pp\nmanifest_20200623_44190_xlrcbb.pp\nmanifest_20200623_44434_19cjntc.pp\nmanifest_20200623_44434_1jx3doo.pp\nmanifest_20200623_44434_1smu6yu.pp\nmanifest_20200623_44434_1u3b4mx.pp\nmanifest_20200623_44434_3ly1x7.pp\nmanifest_20200623_44434_47kln0.pp\nmanifest_20200623_44434_f308bk.pp\nmanifest_20200623_44434_i2btyu.pp\nmanifest_20200623_44434_sfjv8m.pp\nmanifest_20200623_44434_unnvkv.pp\nmanifest_20200623_44434_vp776h.pp\nmanifest_20200624_49267_1a1jlju.pp\nmanifest_20200624_49267_1l00glp.pp\nmanifest_20200624_49267_908wir.pp\nmanifest_20200624_49267_jpbmno.pp\nmanifest_20200624_49267_tuqhen.pp\nmanifest_20200624_49267_w8ul17.pp\nmanifest_20200624_49573_10h19kd.pp\nmanifest_20200624_49573_1plh7h6.pp\nmanifest_20200624_49573_1r31p6c.pp\nmanifest_20200624_49573_336mn7.pp\nmanifest_20200624_49573_55rvj.pp\nmanifest_20200624_49573_gsx71m.pp\nmanifest_20200624_49724_1ckdy0w.pp\nmanifest_20200624_49724_1nzgs98.pp\nmanifest_20200624_49724_85h8t7.pp\nmanifest_20200624_49724_md3gjn.pp\nmanifest_20200624_49724_u0jgnr.pp\nmanifest_20200624_50029_1sbezi2.pp\nmanifest_20200624_50029_1ugxi7j.pp\nmanifest_20200624_50029_u4o2gi.pp\nmanifest_20200624_50141_16fqrkw.pp\nmanifest_20200624_50141_1u41mrr.pp\nmanifest_20200624_50141_1xmtwhc.pp\nmanifest_20200624_50538_153o95v.pp\nmanifest_20200624_50538_3kiocu.pp\nmanifest_20200624_50538_ufdqd9.pp\nmanifest_20200624_50608_fz1coa.pp\nmanifest_20200624_50608_ptuwhr.pp\nmanifest_20200624_50608_qvgfbv.pp\nmanifest_20200624_50675_162gic8.pp\nmanifest_20200624_50675_1daji8m.pp\nmanifest_20200624_50675_1w7zy3p.pp\nmanifest_20200624_50723_11uvwo9.pp\nmanifest_20200624_50723_13farn8.pp\nmanifest_20200624_50723_14qgcoo.pp\nmanifest_20200624_50723_1j5z19k.pp\nmanifest_20200624_50723_1pqpciy.pp\nmanifest_20200624_50723_1q21n7c.pp\nmanifest_20200624_50723_1yjzbup.pp\nmanifest_20200624_50723_31lxzw.pp\nmanifest_20200624_50723_ddmwfx.pp\nmanifest_20200624_50723_fxqijx.pp\nmanifest_20200624_50723_yqj92c.pp\noriginal-ks.cfg\npe.conf\npuppet-enterprise-2019.7.0-el-8-x86_64\npuppet-enterprise-2019.7.0-el-8-x86_64.tar\npuppetlabs-servicenow_cmdb_integration-0.1.0.tar.gz\n", stderr="">
irb(main):005:0>
irb(main):006:0> # Use the CMDB helpers to do stuff on ServiceNow's CMDB
irb(main):007:0> CMDBHelpers.get_target_record(master)
=> nil
irb(main):008:0> # Use Litmus' helpers to do stuff on the ServiceNow instance
irb(main):009:0> servicenow_instance.run_bolt_task('servicenow_tasks::get_records', { 'table' => 'cmdb_ci', 'url_params' => {'sysparm_limit' => 1}}) 
=> #<OpenStruct exit_code=0, stdout="{\"result\"=>[{\"attested_date\"=>\"\", \"skip_sync\"=>\"false\", \"operational_status\"=>\"1\", \"sys_updated_on\"=>\"2019-03-05 21:54:31\", \"attestation_score\"=>\"\", \"u_puppet_classes\"=>\"\", \"discovery_source\"=>\"\", \"first_discovered\"=>\"\", \"sys_updated_by\"=>\"admin\", \"due_in\"=>\"\", \"sys_created_on\"=>\"2019-03-05 21:54:31\", \"sys_domain\"=>{\"link\"=>\"https://dev57373.service-now.com/api/now/table/sys_user_group/global\", \"value\"=>\"global\"}, \"install_date\"=>\"\", \"gl_account\"=>\"\", \"invoice_number\"=>\"\", \"sys_created_by\"=>\"admin\", \"warranty_expiration\"=>\"\", \"asset_tag\"=>\"\", \"fqdn\"=>\"\", \"change_control\"=>\"\", \"owned_by\"=>\"\", \"checked_out\"=>\"\", \"sys_domain_path\"=>\"/\", \"u_puppet_environment\"=>\"\", \"delivery_date\"=>\"\", \"maintenance_schedule\"=>\"\", \"install_status\"=>\"1\", \"cost_center\"=>\"\", \"attested_by\"=>\"\", \"supported_by\"=>\"\", \"dns_domain\"=>\"\", \"name\"=>\"Unknown\", \"assigned\"=>\"\", \"purchase_date\"=>\"\", \"subcategory\"=>\"\", \"short_description\"=>\"This CI is referenced by all duplicate CIs that were upgraded to New York. Before upgrade, discovery_source for these CIs was set to ‘Duplicate’. After upgrade, these CIs are updated to have the new Duplicate Of attribute. However, since the master CI for these upgraded duplicate CIs is unknown, Duplicate Of references the CI ‘Unknown’.\", \"assignment_group\"=>\"\", \"managed_by\"=>\"\", \"managed_by_group\"=>\"\", \"can_print\"=>\"false\", \"last_discovered\"=>\"\", \"sys_class_name\"=>\"cmdb_ci\", \"manufacturer\"=>\"\", \"sys_id\"=>\"8fbc3c053bc07300b924874064efc4ae\", \"po_number\"=>\"\", \"checked_in\"=>\"\", \"sys_class_path\"=>\"/!!\", \"mac_address\"=>\"\", \"vendor\"=>\"\", \"company\"=>\"\", \"justification\"=>\"\", \"model_number\"=>\"\", \"department\"=>\"\", \"assigned_to\"=>\"\", \"start_date\"=>\"\", \"comments\"=>\"\", \"cost\"=>\"\", \"sys_mod_count\"=>\"0\", \"monitor\"=>\"false\", \"serial_number\"=>\"\", \"ip_address\"=>\"\", \"model_id\"=>\"\", \"duplicate_of\"=>\"\", \"sys_tags\"=>\"\", \"cost_cc\"=>\"USD\", \"order_date\"=>\"\", \"schedule\"=>\"\", \"support_group\"=>\"\", \"environment\"=>\"\", \"due\"=>\"\", \"attested\"=>\"false\", \"correlation_id\"=>\"\", \"unverified\"=>\"false\", \"attributes\"=>\"\", \"location\"=>\"\", \"asset\"=>\"\", \"category\"=>\"\", \"fault_count\"=>\"0\", \"lease_id\"=>\"\"}]}", stderr=nil, result={"result"=>[{"attested_date"=>"", "skip_sync"=>"false", "operational_status"=>"1", "sys_updated_on"=>"2019-03-05 21:54:31", "attestation_score"=>"", "u_puppet_classes"=>"", "discovery_source"=>"", "first_discovered"=>"", "sys_updated_by"=>"admin", "due_in"=>"", "sys_created_on"=>"2019-03-05 21:54:31", "sys_domain"=>{"link"=>"https://dev57373.service-now.com/api/now/table/sys_user_group/global", "value"=>"global"}, "install_date"=>"", "gl_account"=>"", "invoice_number"=>"", "sys_created_by"=>"admin", "warranty_expiration"=>"", "asset_tag"=>"", "fqdn"=>"", "change_control"=>"", "owned_by"=>"", "checked_out"=>"", "sys_domain_path"=>"/", "u_puppet_environment"=>"", "delivery_date"=>"", "maintenance_schedule"=>"", "install_status"=>"1", "cost_center"=>"", "attested_by"=>"", "supported_by"=>"", "dns_domain"=>"", "name"=>"Unknown", "assigned"=>"", "purchase_date"=>"", "subcategory"=>"", "short_description"=>"This CI is referenced by all duplicate CIs that were upgraded to New York. Before upgrade, discovery_source for these CIs was set to ‘Duplicate’. After upgrade, these CIs are updated to have the new Duplicate Of attribute. However, since the master CI for these upgraded duplicate CIs is unknown, Duplicate Of references the CI ‘Unknown’.", "assignment_group"=>"", "managed_by"=>"", "managed_by_group"=>"", "can_print"=>"false", "last_discovered"=>"", "sys_class_name"=>"cmdb_ci", "manufacturer"=>"", "sys_id"=>"8fbc3c053bc07300b924874064efc4ae", "po_number"=>"", "checked_in"=>"", "sys_class_path"=>"/!!", "mac_address"=>"", "vendor"=>"", "company"=>"", "justification"=>"", "model_number"=>"", "department"=>"", "assigned_to"=>"", "start_date"=>"", "comments"=>"", "cost"=>"", "sys_mod_count"=>"0", "monitor"=>"false", "serial_number"=>"", "ip_address"=>"", "model_id"=>"", "duplicate_of"=>"", "sys_tags"=>"", "cost_cc"=>"USD", "order_date"=>"", "schedule"=>"", "support_group"=>"", "environment"=>"", "due"=>"", "attested"=>"false", "correlation_id"=>"", "unverified"=>"false", "attributes"=>"", "location"=>"", "asset"=>"", "category"=>"", "fault_count"=>"0", "lease_id"=>""}]}>