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# [0.46.0](v0.45.0...v0.46.0) (2021-05-05)

### Features

* validate `x-sdk-operations` extension ([#290](#290)) ([019c06f](019c06f))

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OpenAPI Validator

This command line tool lets you validate OpenAPI documents according to their specification, either 2.0 or 3.0, as well as IBM-defined best practices.


  • Node 10.x
  • NPM 5.x

Table of contents

Getting Started

The validator analyzes your API definition and reports any problems within. The validator is highly customizable, and supports both OpenAPI 3.0 and OpenAPI 2.0 (Swagger 2.0) formats. The tool also supports a number of rules from Spectral. You can easily extend the tool with custom rules to meet your specific needs and ensure compliance to your standards.

The default configuration uses both OpenAPI 3.0 rules as well as Spectral rules. The default mode section decscribes these rules. Get started by installing the tool, then run the tool on your API definition.


You can modify the behavior of the validator for your project to meet your preferred standards. Specific validation "rules" can be turned off, or configured to trigger an error, warning, info, or hint message in the validator output.

Some validations can be configured even further, such as switching the case convention for parameter names. There are also currently some validations that cannot be disabled or configured to a different severity. You can see the rule associated with each message produced by the validator with the -v command line option. Rules that are not configurable will show the name builtin.

The validator also employs the Spectral validation/linting engine to detect certain issues in the API document. Spectral rules can also be configured to trigger an error, warning, info, or hint message in the validator output with the .spectral.yaml configuration file. When the validator issues a message as the result of a Spectral rule, the rule name displayed will correspond to the Spectral rule. You must add a Spectral configuration if you want to create a new rule, as opposed to modifying an existing one.

To get started configuring the validator, set up a configuration file. See the Spectral configuration section for more details on customization with Spectral.


There are two main ways to install the validator, either using NPM or building from source. Installing with NPM is reccomended.

Install with NPM (recommended)

npm install -g ibm-openapi-validator

The -g flag installs the tool globally so that the validator can be run from anywhere in the file system. Alternatively, you can pass no flag or the --save-dev flag to add the validator as a dependency to your project and run it from your NPM scripts.

Build from source

  1. Clone or download this repository
  2. Navigate to the root directory of this project.
  3. Install the dependencies using npm install
  4. Build the command line tool by running npm run link.

If you installed the validator using npm install -g ibm-openapi-validator, you will need to run npm uninstall -g ibm-openapi-validator before running npm run link.

Platform specific binaries

It is possible to build platform specific binaries for Linux, MacOS, and Windows that do not depend on having node.js installed.

To build these, run npm run pkg in the root. The binaries (lint-openapi-linux, lint-openapi-macos, lint-openapi-windows.exe respectively) are built in the 'bin' directory in the root.

Docker container

A community Docker image is publicly available on Docker hub.

docker pull jamescooke/openapi-validator

Once pulled, the container can be run directly, but mount a volume containing the OpenAPI specification file so that it can be accessed.

docker run --volume "$PWD":/data jamescooke/openapi-validator [options] [command] [<files>]


Command line

lint-openapi [options] [command] [<files>]

  • -c (--config) <path/to/your/config> : Path to a validator configuration file. If provided, this is used instead of .validaterc.
  • -d (--default_mode) : This option turns off configuration and runs the validator in default mode.
  • -e (--errors_only) : Only print the errors, ignore the warnings.
  • -j (--json) : Output results as a JSON object
  • -n (--no_colors) : The output is colored by default. If this bothers you, this flag will turn off the coloring.
  • -p (--print_validator_modules) : Print the name of the validator source file the error/warning was caught it. This can be helpful for developing validations.
  • -v (--verbose) : Increase verbosity of reported results. Use this option to display the rule for each reported result.
  • -r (--ruleset) <path/to/your/ruleset> : Path to Spectral ruleset file, used instead of .spectral.yaml if provided.
  • -s (--report_statistics) : Print a simple report at the end of the output showing the frequency, in percentage, of each error/warning.
  • --debug : Enable debugging output.
  • --version : Print the current semantic version of the validator
  • -h (--help) : This option prints the usage menu.

These options only apply to running the validator on a file, not to any commands.


$ lint-openapi init

  • init : The init command initializes a .validaterc file, used to configure the validator. It can also be used to reset the configurable rules to their default values.

$ lint-openapi migrate

  • migrate : The migrate command migrates a .validaterc file from the legacy format to the current format, retaining all custom rules. The new format is required - this command provides an option to keep custom rules without manually updating the file or initializing a new configuration file with all rules set to the defaults using lint-openapi init.

None of the above options pertain to these commands.

  • The OpenAPI document(s) to be validated. All files must be a valid JSON or YAML (only .json, .yml, and .yaml file extensions are supported).
  • Multiple, space-separated files can be passed in and each will be validated. This includes support for globs (e.g. lint-openapi files/* will run the validator on all files in files/)

Node module

const validator = require('ibm-openapi-validator');

  .then(validationResults => {
    console.log(JSON.stringify(validationResults, null, 2));

// or, if inside `async` function
const validationResults = await validator(openApiDoc);
console.log(JSON.stringify(validationResults, null, 2));


validator(openApiDoc, [defaultMode = false])

Returns a Promise with the validation results.


Type: Object An object that represents an OpenAPI document.


Type: boolean Default: false If set to true, the validator will ignore the .validaterc file and will use the configuration defaults.

Validation results

The Promise returned from the validator resolves into a JSON object. The structure of the object is:

      path: ''
      message: 'Major problem in the OpenAPI document.'
      path: ''
      message: 'Minor problem in the OpenAPI document.'

The object will always have errors and warnings keys that map to arrays. If an array is empty, that means there were no errors/warnings in the OpenAPI document.


Use these sections to customize your traditional and Spectral rules to reflect your API standards.


To set up the configuration capability, simply run the command lint-openapi init. This will create (or overwrite) a .validaterc file with all rules set to their default value. This command does not create a .validateignore. That file must be created manually. These rules can then be changed to configure the validator. Continue reading for more details.

WARNING: If a .validaterc file already exists and has been customized, this command will reset all rules to their default values.

It is recommended to place these files in the root directory of your project. The code will recursively search up the filesystem for these files from wherever the validator is being run. Wherever in the file system the validator is being run, the nearest versions of these files will be used.



The validator supports two API definition specifications - OpenAPI 2.0, aka Swagger 2.0, and OpenAPI 3.0. The validator will automatically determine which spec a document is written in. There are some rules in the validator that only apply to one of the specs and some rules that apply to both. The configuration structure is organized by these "specs". The supported specs are described below:

Spec Description
swagger2 Rules pertaining only to the OpenAPI 2.0 specification.
oas3 Rules pertaining only to the OpenAPI 3.0 specification
shared Rules pertaining to both of the above specifications.


Rules are further organized by categories. Not every category is supported in every spec - these are a superset of the available categories. For the actual structure, see the default values. The supported categories are described below:

Category Description
operations Rules pertaining to Operation Objects
parameters Rules pertaining to Parameter Objects
paths Rules pertaining to Paths Objects
schemas Rules pertaining to Schema Objects
security_definitions Rules pertaining to Security Definition Objects
security Rules pertaining to Security Objects
walker Rules pertaining to the entire document.
pagination Rules pertaining to pagination


Each category contains a group of rules. The spec that each rule applies to is marked in the third column. For the actual configuration structure, see the default values. You can use the -v option of the CLI validator to display the rule for each reported result. The supported rules are described below:

Rule Description Spec
undefined_tag Flag a tag that is in operations and not listed in tags on the top level. shared
unused_tag Flag a tag that is listed in tags on the top level that is not used in the spec. shared
no_consumes_for_put_or_post Flag put or post operations that do not have a consumes field. swagger2
get_op_has_consumes Flag get operations that contain a consumes field. swagger2
no_produces Flag operations that do not have a produces field (except for head and operations that return a 204). swagger2
no_operation_id Flag any operations that do not have an operationId field. shared
operation_id_case_convention Flag any operationId that does not follow a given case convention. shared
no_summary Flag any operations that do not have a summary field. shared
no_array_responses Flag any operations with a top-level array response. shared
parameter_order Flag any operations with optional parameters before a required param. shared
operation_id_naming_convention Flag any operationId that does not follow naming convention. shared
no_request_body_name Flag any operations with a non-form requestBody that does not have a name set with x-codegen-request-body-name. oas3
Rule Description Spec
pagination_style Flag any parameter or response schema that does not follow pagination requirements. oas3
Rule Description Spec
required_param_has_default Flag any required parameter that specifies a default value. shared
no_parameter_description Flag any parameter that does not contain a description field. shared
param_name_case_convention Flag any parameter with a name field that does not follow a given case convention. shared
invalid_type_format_pair Flag any parameter that does not follow the data type/format rules. shared
content_type_parameter Flag any parameter that explicitly defines a Content-Type. That should be defined by the consumes field. shared
accept_type_parameter Flag any parameter that explicitly defines an Accept type. That should be defined by the produces field. shared
authorization_parameter Flag any parameter that explicitly defines an Authorization type. That should be defined by the securityDefinitions/security fields. shared
Rule Description Spec
missing_path_parameter For a path that contains path parameters, flag any operations that do not correctly define those parameters. shared
snake_case_only Flag any path segment that does not use snake case. shared
paths_case_convention Flag any path segment that does not follow a given case convention. snake_case_only must be 'off' to use. shared
duplicate_path_parameter Flag any path parameters that have identical definitions in all operations. shared
Rule Description Spec
inline_response_schema Flag any response object with a schema that doesn't reference a named model. Even if the model is only used once, naming it offers significant benefits for SDK generation. shared
no_success_response_codes Flag any response object that has no success response codes. oas3
no_response_body Flag any non-204 success responses without a response body. oas3
ibm_status_code_guidelines Flag any violations of status code conventions per IBM API Handbook oas3
Rule Description Spec
invalid_type_format_pair Flag any schema that does not follow the data type/format rules. shared
snake_case_only Flag any property with a name that is not lower snake case. shared
no_schema_description Flag any schema without a description field. shared
no_property_description Flag any schema that contains a 'property' without a description field. shared
description_mentions_json Flag any schema with a 'property' description that mentions the word 'JSON'. shared
array_of_arrays Flag any schema with a 'property' of type array with items of type array. shared
inconsistent_property_type Flag any properties that have the same name but an inconsistent type. shared
property_case_convention Flag any property with a name that does not follow a given case convention. snake_case_only must be 'off' to use. shared
property_case_collision Flag any property with a name that is identical to another property's name except for the naming convention shared
enum_case_convention Flag any enum with a value that does not follow a given case convention. snake_case_only must be 'off' to use. shared
json_or_param_binary_string Flag parameters or application/json request/response bodies with schema type: string, format: binary. oas3
undefined_required_properties Flag any schema with undefined required properties shared
Rule Description Spec
unused_security_schemes Flag any security scheme defined in securityDefinitions that is not used in the spec. shared
unused_security_scopes Flag any security scope defined in securityDefinitions that is not used in the spec. shared
Rule Description Spec
invalid_non_empty_security_array Flag any non-empty security array this is not of type OAuth2 shared
Rule Description Spec
no_empty_descriptions Flag any description field in the spec with an empty or whitespace string. shared
has_circular_references Flag any circular references found in the API document. shared
$ref_siblings Flag any properties that are siblings of a $ref property. shared
duplicate_sibling_description Flag descriptions sibling to $ref if identical to referenced description. shared
incorrect_ref_pattern Flag internal $ref values that do not point to the section they should (e.g. referencing parameters from a schema field). shared


Each rule can be assigned a status. The supported statuses are error, warning, info, hint and off. Some rules can be configured further with configuration options. The format of this configuration is to provide an array, rather than just a string. e.g. "param_name_case_convention": ["error", "lower_camel_case"] If just a string is provided for these rule, the default configuration option will be used. If only one value is provided in the array, it MUST be a status. The default configuration option will be used in this case as well. The rules that support configuration options will have two values in the defaults table.

Configuration Options

For rules that accept additional configuration, there will be a limited set of available options.

Case Convention Options
  • Some rules check strings for adherence to a specific case convention. In some cases, the case convention checked is configurable.
  • Rules with configurable case conventions will end in _case_convention, such as param_name_case_convention.
Option Description Example
lower_snake_case Words must follow standard lower snake case conventions. learning_opt_out
upper_snake_case Words must follow standard upper snake case conventions. LEARNING_OPT_OUT
upper_camel_case Words must follow standard upper camel case conventions. LearningOptOut
lower_camel_case Words must follow standard lower camel case conventions. learningOptOut
k8s_camel_case Words must follow Kubernetes API camel case conventions. learningOptOutAPI
lower_dash_case Words must follow standard lower dash case conventions. learning-opt-out
upper_dash_case Words must follow standard upper dash case conventions. LEARNING-OPT-OUT

Configuration file

Non-Spectral configurations are defined in a file, titled .validaterc. Spectral rules must be configured in .spectral.yaml rather than in .validaterc. Additionally, certain files can be ignored by the validator. Any glob placed in a file called .validateignore will always be ignored by the validator at runtime. This is set up like a .gitignore or a .eslintignore file.

The configuration file must be structured as a JSON object with specs as first-level keys, categories as second-level keys, rules as third-level keys, and statuses as values for the 'rules' objects.

If a rule is not included in the file, that rule will be set to the default status automatically. See the Default Values for more info.

For an example of the structure, see the defaults file.

The easiest way to create a .validaterc file is using the initialization command.

Default mode

The validator has a set of predefined default statuses for each rule that are used in 'default mode'.

Default mode can be turned on with the command line option -d. If this option is given, the .validaterc file will be ignored.

If a .validaterc file does not exist at the root directory of your project, the validator will automatically run in default mode.

The default values for each rule are described below.

Default values

Rule Default
no_consumes_for_put_or_post error
get_op_has_consumes warning
no_produces error
Rule Default
no_request_body_name warning
Rule Default
has_schema_and_content error
Rule Default
no_success_response_codes warning
no_response_body warning
ibm_status_code_guidelines warning
Rule Default
json_or_param_binary_string warning
undefined_required_properties warning
Rule Default
undefined_tag warning
unused_tag warning
no_operation_id warning
operation_id_case_convention warning, lower_snake_case
no_summary warning
no_array_responses error
parameter_order warning
operation_id_naming_convention warning
Rule Default
pagination_style warning
Rule Default
no_parameter_description error
param_name_case_convention error, lower_snake_case
invalid_type_format_pair error
content_type_parameter error
accept_type_parameter error
authorization_parameter warning
required_param_has_default warning
Rule Default
missing_path_parameter error
snake_case_only off
paths_case_convention error, lower_snake_case
Rule Default
inline_response_schema warning
Rule Default
unused_security_schemes warning
unused_security_scopes warning
Rule Default
invalid_non_empty_security_array error
Rule Default
invalid_type_format_pair error
snake_case_only off
no_schema_description warning
no_property_description warning
description_mentions_json warning
array_of_arrays warning
inconsistent_property_type warning, [code, default, type, value]]
(list of property names to exclude)
property_case_convention error, lower_snake_case
property_case_collision error
enum_case_convention warning, lower_snake_case
Rule Default
no_empty_descriptions error
has_circular_references warning
$ref_siblings off
duplicate_sibling_description warning
incorrect_ref_pattern warning

Spectral configuration

Currently the validator configures Spectral to check the following rules from its “oas" ruleset:

no-eval-in-markdown: true
no-script-tags-in-markdown: true
openapi-tags: true
operation-description: true
operation-operationId-unique: true
operation-parameters: true
operation-tags: true
operation-tag-defined: true
path-keys-no-trailing-slash: true
path-not-include-query: true
typed-enum: true
oas2-api-host: true
oas2-api-schemes: true
oas2-host-trailing-slash: true
oas2-valid-example: true
oas2-valid-definition-example: true
oas2-anyOf: true
oas2-oneOf: true
oas2-operation-formData-consume-check: true
oas3-api-servers: true
oas3-examples-value-or-externalValue: true
oas3-server-trailing-slash: true
oas3-schema: true
oas3-valid-example: true
oas3-valid-schema-example: true

This ruleset has the alias ibm:oas, and you can "extend" this ruleset or specify your own custom ruleset with a Spectral ruleset file. Note that all of the rules in the spectral:oas ruleset are defined in ibm:oas but only the rules listed above are enabled by default.

The ibm:oas ruleset also includes custom Spectral rules, documented here. These are configurable rules in the ibm:oas ruleset that are not part of the spectral:oas ruleset.

You can provide a Spectral ruleset file to the IBM OpenAPI validator in a file named .spectral.yaml in the current directory or with the --ruleset command line option of the validator.

Changing Spectral rule severity

Any rule in the ibm:oas ruleset can be configured to trigger an error, warning, info, or hint message in the validator output. For example, to configure the openapi-tags rule to trigger an info message instead of a warning, specify the following in your Spectral ruleset file:

extends: ibm:oas
  openapi-tags: warn

To completely disable a rule, use the severity of off. For example, to disable the operation-tags rule, specify the following in your Spectral ruleset file:

extends: ibm:oas
  operation-tags: off

Since the ibm:oas ruleset includes all the rules in spectral:oas, you can also enable rules from that ruleset that are disabled by default in ibm:oas. For example, to enable the info-contact rule with it's default severity (warning), specify the following in your Spectral ruleset file:

extends: ibm:oas
  info-contact: true

You could also set the severity of info-contact explicitly to error, warn, info, or hint.

Custom Spectral rules

New custom rules can be specified using a simple but powerful yaml syntax or with custom Javascript functions. Use the documentation on Spectral custom rules in order to add these to your .spectral.yaml file.

Warnings Limit

You may impose a warning limit on your API definitions. If the number of warnings issued exceeds the warning limit, the exit code will be set to 1. If the Validator is part of your CI build, this will cause the build to fail.

To impose a warnings limit on a project, add a .thresholdrc to your project. It is recommended to add this file to the root of the project. The validator recursively searches up the filesystem from whichever directory the validator is invoked, and the nearest .thresholdrc will be used.

The format for the .thresholdrc file is a top-level JSON object with a "warnings" field (shown below).

  "warnings": 0
Limit Default
warnings MAX_VALUE

Turning off update-notifier

This package uses update-notifier to alert users when new versions of the tool are available. To turn this feature off, follow these instructions from the package authors. It is recommended to keep this feature on to help stay up to date with the latest changes.


Copyright 2017 SmartBear Software

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

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.