[JDL/Enum]: Parsing issues with special chars / Missing quotes on export / JDL-injection with enums

##### **Overview of the issue**

Summary: There are several issues with the jdl query parser, the way enum values are stored internally and on export
- Enums like   `QUOTES("\"")` or `COMMA_SPACE (", ")`  , both correctly escaped and quoted, can't be imported
- Enums with special chars won't be exported correctly. Jhipster export jdl generated no quotes for special characters.
- Even  JDL-injection with enums is possible causes by the way how enum values are stored internally.


Examples and steps to reproduce:

**Example 1:** Missing quotes on export and Enum injection

##### **JHipster JDL**

  <details>
  <summary>JDL definitions (Example 1)</summary>
  <pre>
application {
  config {
    applicationType monolith
    authenticationType jwt
    baseName jdlbugs
    buildTool maven
    cacheProvider ehcache
    clientFramework angular
    clientTheme none
    creationTimestamp 1760733393175
    databaseType sql
    devDatabaseType h2Disk
    enableHibernateCache true
    enableTranslation true
    jhipsterVersion "9.0.0-alpha.0"
    jwtSecretKey "ZjNhZDE2MGIxMDFkMGU5ZDI0ODE1ZmVkYjlmZjgxOTIyMzE4OGE1ODUyMGNmZjlmOTUyMGYxYTFkOTIzYzU2NzAxMWQyMjZiNzczOGJmYzZjOTE1MjIzMTUzYWViOTBmYTdlZmU3Y2RkOTVlY2U1NGRmOTRlMDJmMTc0MjI2MTg="
    languages [en]
    microfrontends []
    nativeLanguage en
    packageName com.mycompany.myapp
    prodDatabaseType postgresql
    reactive false
    testFrameworks []
    withAdminUi true
  }
  
  entities Test
}

entity Test {
  test SpecialChars
}

enum SpecialChars {
  Ue ("Ü") // special character, has to be quoted
  Try_to_inject_enum_in_entity_json("a), InjectedEnum(a")
}
  </pre>
  </details>

Import enum-special-chars1.jdl:

`jhipster import-jdl enum-special-chars1.jdl`

Export Jdl:

`jhipster export-jdl enum-special-chars-export.jdl`

Result is:

  <details>
  <summary>JDL definitions (Example 1 exported)</summary>
  <pre>
application {
  config {
    applicationType monolith
    authenticationType jwt
    baseName jdlbugs
    buildTool maven
    cacheProvider ehcache
    clientFramework angular
    clientTheme none
    creationTimestamp 1760733393175
    databaseType sql
    devDatabaseType h2Disk
    enableHibernateCache true
    enableTranslation true
    jhipsterVersion "9.0.0-alpha.0"
    jwtSecretKey "ZjNhZDE2MGIxMDFkMGU5ZDI0ODE1ZmVkYjlmZjgxOTIyMzE4OGE1ODUyMGNmZjlmOTUyMGYxYTFkOTIzYzU2NzAxMWQyMjZiNzczOGJmYzZjOTE1MjIzMTUzYWViOTBmYTdlZmU3Y2RkOTVlY2U1NGRmOTRlMDJmMTc0MjI2MTg="
    languages [en]
    microfrontends []
    nativeLanguage en
    packageName com.mycompany.myapp
    prodDatabaseType postgresql
    reactive false
    testFrameworks []
    withAdminUi true
  }

  entities Test
}

@ChangelogDate("20251017204639")
entity Test {
  test SpecialChars
}

enum SpecialChars {
  Ue (Ü),
  Try_to_inject_enum_in_entity_json (a),
  InjectedEnum(a)
}

search Test with no
  </pre>
  </details>

Import exported jdl:

`jhipster import-jdl enum-special-chars-export.jdl`

results in this exception:
```
[..]
Welcome to JHipster v9.0.0-alpha.0

INFO! Generating jdls enum-special-chars-export.jdl
ERROR! An error occured while running jhipster:jdl#parseJDL
ERROR! ERROR! unexpected character: ->Ü<- at offset: 881, skipped 1 characters.
Error: unexpected character: ->Ü<- at offset: 881, skipped 1 characters.
    at getCst (generator-jhipster/dist/lib/jdl/core/parsing/api.js:31:15)
    at parse (generator-jhipster/dist/lib/jdl/core/parsing/api.js:24:17)
    at parse (generator-jhipster/dist/lib/jdl/core/readers/jdl-reader.js:78:31)
    at parseFromContent (generator-jhipster/dist/lib/jdl/core/readers/jdl-reader.js:44:12)
    at createImporterFromContent (generator-jhipster/dist/lib/jdl/jdl-importer.js:61:21)
    at JdlGenerator.parseJDL (generator-jhipster/dist/generators/jdl/generator.js:116:34)
    at JdlGenerator.executeTask (generator-jhipster/node_modules/yeoman-generator/dist/actions/lifecycle.js:265:26)
    at env.queueTask.once (generator-jhipster/node_modules/yeoman-generator/dist/actions/lifecycle.js:232:56)
    at runLoop.add.once (generator-jhipster/node_modules/yeoman-environment/dist/environment-base.js:383:23)
    at Immediate.<anonymous> (generator-jhipster/node_modules/grouped-queue/lib/subqueue.js:52:34)
```




**Example 2**: JDL parser can't handle quoted and escaped special characters correctly

  <details>
  <summary>JDL definitions (Example 2)</summary>
  <pre>
application {
  config {
    applicationType monolith
    authenticationType jwt
    baseName jdlbugs
    buildTool maven
    cacheProvider ehcache
    clientFramework angular
    clientTheme none
    creationTimestamp 1760733393175
    databaseType sql
    devDatabaseType h2Disk
    enableHibernateCache true
    enableTranslation true
    jhipsterVersion "9.0.0-alpha.0"
    jwtSecretKey "ZjNhZDE2MGIxMDFkMGU5ZDI0ODE1ZmVkYjlmZjgxOTIyMzE4OGE1ODUyMGNmZjlmOTUyMGYxYTFkOTIzYzU2NzAxMWQyMjZiNzczOGJmYzZjOTE1MjIzMTUzYWViOTBmYTdlZmU3Y2RkOTVlY2U1NGRmOTRlMDJmMTc0MjI2MTg="
    languages [en]
    microfrontends []
    nativeLanguage en
    packageName com.mycompany.myapp
    prodDatabaseType postgresql
    reactive false
    testFrameworks []
    withAdminUi true
  }
  
  entities Test
}

entity Test {
  test SpecialChars2
}

enum SpecialChars2 {
  ESCAPING_WORKS("\\")
  ESCAPED_QUOTES_FAIL("\"")
}
  </pre>
  </details>

`jhipster import-jdl enum-special-chars2.jdl`

results in this exception:

```
Welcome to JHipster v9.0.0-alpha.0

INFO! Generating jdls enum-special-chars.jdl
ERROR! An error occured while running jhipster:jdl#parseJDL
ERROR! ERROR! unexpected character: ->"<- at offset: 892, skipped 1 characters.
Error: unexpected character: ->"<- at offset: 892, skipped 1 characters.
    at getCst (generator-jhipster/dist/lib/jdl/core/parsing/api.js:31:15)
    at parse (generator-jhipster/dist/lib/jdl/core/parsing/api.js:24:17)
    at parse (generator-jhipster/dist/lib/jdl/core/readers/jdl-reader.js:78:31)
    at parseFromContent (generator-jhipster/dist/lib/jdl/core/readers/jdl-reader.js:44:12)
    at createImporterFromContent (generator-jhipster/dist/lib/jdl/jdl-importer.js:61:21)
    at JdlGenerator.parseJDL (generator-jhipster/dist/generators/jdl/generator.js:116:34)
    at JdlGenerator.executeTask (generator-jhipster/node_modules/yeoman-generator/dist/actions/lifecycle.js:265:26)
    at env.queueTask.once (generator-jhipster/node_modules/yeoman-generator/dist/actions/lifecycle.js:232:56)
    at runLoop.add.once (generator-jhipster/node_modules/yeoman-environment/dist/environment-base.js:383:23)
    at Immediate.<anonymous> (generator-jhipster/node_modules/grouped-queue/lib/subqueue.js:52:34)

```

**Example 3**: JDL parser can't handle enum values with comma and space

  <details>
  <summary>JDL definitions (Example 3)</summary>
  <pre>
application {
  config {
    applicationType monolith
    authenticationType jwt
    baseName jdlbugs
    buildTool maven
    cacheProvider ehcache
    clientFramework angular
    clientTheme none
    creationTimestamp 1760733393175
    databaseType sql
    devDatabaseType h2Disk
    enableHibernateCache true
    enableTranslation true
    jhipsterVersion "9.0.0-alpha.0"
    jwtSecretKey "ZjNhZDE2MGIxMDFkMGU5ZDI0ODE1ZmVkYjlmZjgxOTIyMzE4OGE1ODUyMGNmZjlmOTUyMGYxYTFkOTIzYzU2NzAxMWQyMjZiNzczOGJmYzZjOTE1MjIzMTUzYWViOTBmYTdlZmU3Y2RkOTVlY2U1NGRmOTRlMDJmMTc0MjI2MTg="
    languages [en]
    microfrontends []
    nativeLanguage en
    packageName com.mycompany.myapp
    prodDatabaseType postgresql
    reactive false
    testFrameworks []
    withAdminUi true
  }
  
  entities Test
}

entity Test {
  test SpecialChars2
}

enum SpecialChars2 {
  COMMA_SPACE_CANNOT_BE_PARSED (", ")
}
  </pre>
  </details>

`jhipster import-jdl enum-special-chars3.jdl`

results in this exception:

```
Welcome to JHipster v9.0.0-alpha.0

INFO! Generating jdls enum-special-chars3.jdl
     info Generating 1 application
 _______________________________________________________________________________________________________________

  Documentation for creating an application is at https://www.jhipster.tech/creating-an-app/

  Application files will be generated in folder: /home/martin/Jhipster/jdlbugs
 _______________________________________________________________________________________________________________

ERROR! An error occured while running jhipster:base-application:bootstrap#prepareFieldsForTemplates
ERROR! ERROR! Cannot read properties of null (reading '1')
TypeError: Cannot read properties of null (reading '1')
    at generator-jhipster/dist/generators/base-application/support/prepare-field.js:338:26
    at Array.map (<anonymous>)
    at getEnumValuesWithCustomValues (generator-jhipster/dist/generators/base-application/support/prepare-field.js:332:34)
    at prepareCommonFieldForTemplates (generator-jhipster/dist/generators/base-application/support/prepare-field.js:266:28)
    at BootstrapBaseApplicationGenerator.prepareFieldsForTemplates (generator-jhipster/dist/generators/base-application/generators/bootstrap/generator.js:303:17)
    at BootstrapBaseApplicationGenerator.executeTask (generator-jhipster/node_modules/yeoman-generator/dist/actions/lifecycle.js:265:26)
    at env.queueTask.once (generator-jhipster/node_modules/yeoman-generator/dist/actions/lifecycle.js:232:56)
    at runLoop.add.once (generator-jhipster/node_modules/yeoman-environment/dist/environment-base.js:383:23)
    at Immediate.<anonymous> (/home/martin/Jhipster/generator-jhipster/node_modules/grouped-queue/lib/subqueue.js:52:34)
    at process.processImmediate (node:internal/timers:491:21)
```

- [x] JDL is mandatory for bug reports. This will allow us to use automated tests and generate the broken sample using `jhipster from-issue` command.

##### **Motivation for or Use Case**

- The JDL parser should handle special characters in enum values. 
- Special characters in enum values should be exported correctly.
- JDL-injection should not be possible



##### **Reproduce the error**



##### **Related issues**



##### **Suggest a Fix**

The root cause for these issues is how fieldValues for enum are stored. This explains how injection is possible. Jhipster removes all quotes because a single string is used to store enum data:

```
{
  "annotations": {
    "changelogDate": "20251017204639"
  },
  "applications": ["jdlbugs"],
  "fields": [
    {
      "fieldName": "umlaut",
      "fieldType": "SpecialChars",
      "fieldValues": "Ue (Ü),Try_to_inject_enum_in_entity_json (a),InjectedEnum(a)"
    }
  ],
  "name": "Test",
  "relationships": [],
  "searchEngine": "no"
}
```

Parsing a single string for enum values correctly is very complex. I suggest using an array or JSON in general e.q.

```
{
  "annotations": {
    "changelogDate": "20251017204639"
  },
  "applications": ["jdlbugs"],
  "fields": [
    {
      "fieldName": "umlaut",
      "fieldType": "SpecialChars",
      "fieldValues": [
		{
		  "enumFieldName": "Ue",
		  "enumFieldValue": "Ü"
		}
		{
		  "enumFieldName": "Try_to_inject_enum_in_entity_json",
		  "enumFieldValue": "a),InjectedEnum(a"
		}
      ]
    }
  ],
  "name": "Test",
  "relationships": [],
  "searchEngine": "no"
}

```
Injection will fail and exporting with quotes will become simple: If "enumValue" contains a non alphanumeric value, then enumValue has to be exported in qoutes.



##### **JHipster Version(s)**



JHipster v9.0.0-alpha.0 , latest git version

##### **Browsers and Operating System**



- [x] Tickets opened without reproduction steps or that doesn't follows the template recommendation will be **closed**.
- [x] Checking this box is mandatory (this is just to show you read everything)

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[JDL/Enum]: Parsing issues with special chars / Missing quotes on export / JDL-injection with enums #31082

Overview of the issue

JHipster JDL

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Uh oh!

[JDL/Enum]: Parsing issues with special chars / Missing quotes on export / JDL-injection with enums #31082

Description

Overview of the issue

JHipster JDL

Motivation for or Use Case

Reproduce the error

Related issues

Suggest a Fix

JHipster Version(s)

Browsers and Operating System

Metadata

Metadata

Assignees

Labels

Type

Projects

Milestone

Relationships

Development

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