Atata.HtmlValidation

Atata.HtmlValidation is a .NET library that adds HTML page validation to Atata using html-validate NPM package.

The package targets .NET Standard 2.0, which supports .NET 5+, .NET Framework 4.6.1+ and .NET Core/Standard 2.0+.

Table of Contents

• Features
• Installation
• Usage
  • Using ValidateHtml extension method
  • Using ValidateHtmlAttribute trigger
  • Using HtmlValidator
• Configuration
• HtmlValidationOptions properties
• HtmlValidationResult members
• Validation results
  • Exception
  • Result file
  • Log
• Sample project
• Feedback
• Thanks
• SemVer
• License

Features

• Uses CLI of html-validate NPM package.
• Validates HTML of Atata page objects.
• Performs validation offline.
• Supports different result formatters.
• Supports custom validation rule sets by configuration files.
• Saves HTML and validation results to artifact files.
• Can produce either error or warning.

Installation

NuGet package

Install Atata.HtmlValidation NuGet package.

• Package Manager:

  Install-Package Atata.HtmlValidation
  

• .NET CLI:

  dotnet add package Atata.HtmlValidation
  

NPM package

Requires html-validate NPM package, as well as NPM itself, to be installed. By default, when html-validate package is missing, the library automatically tries to install the package, but in case of permissions lack, installation can fail. Therefore, it is recommended when possible to preinstall html-validate package using NPM command:

npm install -g html-validate

Usage

Using ValidateHtml extension method

The primary way to execute validations is using ValidateHtml extension method:

public static TPageObject ValidateHtml<TPageObject>(
    this TPageObject pageObject,
    HtmlValidationOptions options = null,
    bool asWarning = false)
    where TPageObject : PageObject<TPageObject>;

The method validates the HTML of current page. Relies on HtmlValidator class that uses "html-validate" NPM package to execute HTML validation.

Before the execution of validation, the check of installed "html-validate" package version performs. The required package version is defined in HtmlValidatePackageVersion property of options. The required version will be installed if "html-validate" package is not installed or the installed version differs from the required one.

By default, when validation fails, throws an assertion exception with a message containing a list of HTML errors. Produces a warning instead of assertion exception if asWarning argument is set to true.

Validate by default

Go.To<OrdinaryPage>(url: "some/url")
    .ValidateHtml();

Validate as warning

Go.To<OrdinaryPage>(url: "some/url")
    .ValidateHtml(asWarning: true);

Validate with custom options

var options = new HtmlValidationOptions
{
    OutputFormatter = HtmlValidateFormatter.Names.Text,
    ResultFileFormatter = HtmlValidateFormatter.Names.Json,
    ConfigPath = "some/config.json"
};

Go.To<OrdinaryPage>(url: "some/url")
    .ValidateHtml(options);

Validate with options based on default

Go.To<OrdinaryPage>(url: "some/url")
    .ValidateHtml(HtmlValidationOptions.Default.CloneWith(x => x.ConfigPath = "another/config.json"));

Using ValidateHtmlAttribute trigger

ValidateHtmlAttribute - the trigger attribute that indicates that the page HTML should be validated on the specified event. By default occurs upon the page object initialization. Invokes ValidateHtml method using HtmlValidationOptions.Default options.

Has public bool AsWarning { get; set; } property that gets or sets a value indicating whether to produce a warning instead of assertion exception on validation failure. The default value is false.

Apply to certain page object

[ValidateHtml]
public class SomePage : Page<_>
{
}

Apply to all page objects

AtataContext.GlobalConfiguration
    .Attributes.Global.Add(new ValidateHtmlAttribute { TargetType = typeof(PageObject<>) });

Using HtmlValidator

This approach is a bit low-level one. Can be used without active AtataContext.

HtmlValidator - uses "html-validate" NPM package to execute HTML validation. If required version of "html-validate" package is not installed, installs it.

HtmlValidator validator = new HtmlValidator(
    new HtmlValidationOptions()); // HtmlValidationOptions are optional here.

string html = "<html>...</html>";
// string html = webDriver.PageSource;

HtmlValidationResult result = validator.Validate(html);

if (!result.IsSuccessful)
{
    string resultMessage = result.Output;

    // TODO: Handle validation failure case.
}

Configuration

Check out html-validate Configuration documentation page on how to create config files.

Mostly, you can create standard .htmlvalidate.json file in the root of a test project with "Copy to Output Directory" property set to "Copy if newer".

HtmlValidationOptions properties

• static HtmlValidationOptions Default { get; set; }
  Gets or sets the default options.
• string WorkingDirectory { get; set; }
  Gets or sets the working directory where HTML and result files should be saved. The default value is null, meaning to use AtataContext.ArtifactsPath. The other value should be relative to Artifacts directory, for example, a name of subdirectory. The path supports AtataContext template variables.
• int? MaxWarnings { get; set; }
  Gets or sets the maximum allowed warnings count. The default value is null, which means that warnings are allowed. Use 0 to disallow warnings.
• string ConfigPath { get; set; }
  Gets or sets the configuration file path (full or relative to WorkingDirectory).
• string OutputFormatter { get; set; }
  Gets or sets the output formatter name. The default value is HtmlValidateFormatter.Names.Stylish. See HtmlValidateFormatter.Names class for options.
• string ResultFileFormatter { get; set; }
  Gets or sets the result file formatter name. The default value is HtmlValidateFormatter.Names.Codeframe. See HtmlValidateFormatter.Names class for options.
• string ResultFileExtension
  Gets or sets the result file extension, like ".txt" or ".json". The default value is null, which means that extension should be resolved automatically corresponding to ResultFileFormatter value.
• bool SaveResultToFile
  Gets or sets a value indicating whether to save validation result output to file. The default value is true.
• HtmlSaveCondition SaveHtmlToFile
  Gets or sets a value indicating the condition of HTML file saving. The default value is HtmlSaveCondition.Invalid, meaning that HTML file should be saved only when it is not valid. Other available options are: HtmlSaveCondition.Never and HtmlSaveCondition.Always.
• Encoding Encoding
  Gets or sets the encoding to use. The default value is null, which means that default encoding should be used.
• ICliCommandFactory CliCommandFactory
  Gets or sets the CLI command factory. The default value is null, which means that default CLI command factory should be used, which is ProgramCli.DefaultShellCliCommandFactory.
• string HtmlValidatePackageVersion
  Gets or sets the required version of "html-validate" NPM package. The required version will be installed if "html-validate" package is not installed or the installed version differs from the required one. The default value is "8.18.1". Set null to disable the version check and use any pre-installed version.

Configure default options

It is possible to configure default HtmlValidationOptions upon global initialization method.

Change some default values:

HtmlValidationOptions.Default.OutputFormatter = HtmlValidateFormatter.Names.Codeframe;

Reset default options completely:

HtmlValidationOptions.Default = new HtmlValidationOptions
{
    OutputFormatter = HtmlValidateFormatter.Names.Codeframe,
    SaveResultToFile = false,
    ConfigPath = "some/config.json"
};

HtmlValidationResult members

Properties

• bool IsSuccessful { get; }
  Gets a value indicating whether this result is successful.
• string Output { get; }
  Gets the text output of result.
• string HtmlFilePath { get; }
  Gets the HTML file path.
• string ResultFilePath { get; }
  Gets the result file path.

Methods

• HtmlValidationResult MoveFilesToDirectory(string directory)
  Moves the HTML and result files to another directory.

Validation results

The results of failed validation using ValidateHtml method can be found in few places.

Additionally original HTML snapshot, which was validated, is saved to Atata Artifacts directory as a file.

Exception

An AssertionException is thrown with the message similar to:

Wrong "<app>" page HTML document, which contains errors:
785a0e99-359a-4905-b490-3a62c61fbf37.html
  69:22  error  <th> is missing required "scope" attribute     element-required-attributes
  70:22  error  <th> is missing required "scope" attribute     element-required-attributes
  71:22  error  <th> is missing required "scope" attribute     element-required-attributes
  72:22  error  <th> is missing required "scope" attribute     element-required-attributes
  81:26  error  <button> is missing required "type" attribute  element-required-attributes
  82:26  error  <button> is missing required "type" attribute  element-required-attributes
  83:26  error  <button> is missing required "type" attribute  element-required-attributes

✖ 7 problems (7 errors, 0 warnings)

More information:
  https://html-validate.org/rules/element-required-attributes.html

Result file

By default, the result file that is saved to Atata Artifacts directory is generated using "codeframe" formatter, which provides nice detailed report.

error: <th> is missing required "scope" attribute (element-required-attributes) at 785a0e99-359a-4905-b490-3a62c61fbf37.html:69:22:
  67 |             <thead>
  68 |                 <tr>
> 69 |                     <th>Name</th>
     |                      ^^
  70 |                     <th>Price</th>
  71 |                     <th>Amount</th>
  72 |                     <th></th>
Details: https://html-validate.org/rules/element-required-attributes.html


error: <th> is missing required "scope" attribute (element-required-attributes) at 785a0e99-359a-4905-b490-3a62c61fbf37.html:70:22:
  68 |                 <tr>
  69 |                     <th>Name</th>
> 70 |                     <th>Price</th>
     |                      ^^
  71 |                     <th>Amount</th>
  72 |                     <th></th>
  73 |                 </tr>
Details: https://html-validate.org/rules/element-required-attributes.html

...

Log

Additional details of validation execution can be found in Atata log.

...
2024-04-16 19:06:22.708  INFO > Validate: "<app>" page HTML document
2024-04-16 19:06:22.710 TRACE - > Get page source HTML
2024-04-16 19:06:22.731 TRACE - < Get page source HTML (0.021s)
2024-04-16 19:06:22.743 TRACE - HTML saved to file "785a0e99-359a-4905-b490-3a62c61fbf37.html"
2024-04-16 19:06:23.331 TRACE - > Execute html-validate CLI command for "785a0e99-359a-4905-b490-3a62c61fbf37.html" with "stylish" formatter
2024-04-16 19:06:24.259 TRACE - < Execute html-validate CLI command for "785a0e99-359a-4905-b490-3a62c61fbf37.html" with "stylish" formatter (0.927s) >> { IsSuccessful = False }
2024-04-16 19:06:24.261 TRACE - > Execute html-validate CLI command for "785a0e99-359a-4905-b490-3a62c61fbf37.html" with "codeframe" formatter
2024-04-16 19:06:25.116 TRACE - < Execute html-validate CLI command for "785a0e99-359a-4905-b490-3a62c61fbf37.html" with "codeframe" formatter (0.854s) >> { IsSuccessful = False }
2024-04-16 19:06:25.120  INFO - HTML validation report saved to file "785a0e99-359a-4905-b490-3a62c61fbf37.txt"
2024-04-16 19:06:25.480 ERROR - Wrong "<app>" page HTML document, which contains errors:
785a0e99-359a-4905-b490-3a62c61fbf37.html
  69:22  error  <th> is missing required "scope" attribute     element-required-attributes
  70:22  error  <th> is missing required "scope" attribute     element-required-attributes
  71:22  error  <th> is missing required "scope" attribute     element-required-attributes
  72:22  error  <th> is missing required "scope" attribute     element-required-attributes
  81:26  error  <button> is missing required "type" attribute  element-required-attributes
  82:26  error  <button> is missing required "type" attribute  element-required-attributes
  83:26  error  <button> is missing required "type" attribute  element-required-attributes

✖ 7 problems (7 errors, 0 warnings)

More information:
  https://html-validate.org/rules/element-required-attributes.html

2024-04-16 19:06:25.484  INFO < Validate: "<app>" page HTML document (2.775s) >> NUnit.Framework.AssertionException: Wrong "<app>" page HTML document, which contains errors...
...

Sample project

Check out atata-framework/atata-sample-app-tests repository, which contains HtmlPageValidationTests test class that validates HTML of some pages. It also contains a sample .htmlvalidate.json configuration file.

Feedback

Any feedback, issues and feature requests are welcome.

If you faced an issue please report it to Atata.HtmlValidation Issues, ask a question on Stack Overflow using atata tag or use another Atata Contact way.

Thanks

The library is implemented thanks to the sponsorship of Lombiq Technologies.

SemVer

Atata Framework follows Semantic Versioning 2.0. Thus backward compatibility is followed and updates within the same major version (e.g. from 1.3 to 1.4) should not require code changes.

License

Atata is an open source software, licensed under the Apache License 2.0. See LICENSE for details.