pdfgen-core

Repository for pdfgen-core, an application written in Kotlin used to create PDFs and HTMLs

Technologies & Tools

• Kotlin
• Gradle
• Ktor
• Junit
• Handlebars
• VeraPDF-validation
• JDK 21

Getting started

pdfgen-core is used with templates, fonts, additional resources, and potential test data to verify that valid PDFs get produced by the templates.

Check GitHub releases to find the latest release version Check Github releases to find the latest release version

In your own repository create folders templates, resources and data on root of you repository

• templates Create subfolder inside templates folder

  mkdir {templates}/directory_name # directory_name can be anything, but it'll be a necessary part of the API later

  • templates/directory_name/ should then be populated with your .hbs-templates. the names of these templates will also decide parts of the API paths

• resources should contain additional resources (ex images) which can be referred in your .hbs-templates

• data should contain test JSON data that can be used to verify that valid PDFs get produced by templates. data folder should have same subdirectory structure as templates. Example how you can produce HTML and PDF with test data

Initialize pdfgen-core

Initialize with custom handlebar helpers

You can initialize pdfgen-core with additional handlebar helpers:

PDFGenCore.init(Environment(additionalHandlebarHelpers = mapOf(
    "enum_to_readable" to Helper<String> { context, _ ->
        when(context){
            "SOME_ENUM_VALUE" -> "Human readable text"
            else -> ""
        }
    },
)))

Initialize with alternative path to templates, resources folder

PDFGenCore.init(
Environment(
    additionalHandlebarHelpers = mapOf(
        "enum_to_readable" to Helper<String> { context, _ ->
            when (context) {
                "BIDRAGSMOTTAKER" -> "Bidragsmottaker"
                else -> ""
            }
        },
    ),
    templateRoot = PDFGenResource("/path/to/templates"),
    resourcesRoot = PDFGenResource("/path/to/resources"),
),
)

Reload templates and resources from disk

You can reload the resources and templates from disk using the following method. This will be especially useful for when developing templates and should be executed before generating HTML or PDF such that the updated templates and data are loaded from disk

PDFGenCore.reloadEnvironment()

Example usage

Generating HTML from predefined JSON data in data-folder

val html: String = createHtmlFromTemplateData(template, directoryName)

Generating PDF from predefined JSON data in data-folder

val html: String = createHtmlFromTemplateData(template, directoryName)
val pdfBytes: ByteArray = createPDFA(html)

Generating from JSON input data

val html: String = createHtmlFromTemplateData(template, directoryName, jsonNode)
val pdfBytes: ByteArray = createPDFA(html)

// Or directly
val pdfBytes: ByteArray = createPDFA(template, directoryName, jsonNode)

Handlerbars helpers

Example of usage of handlebar helpers defined in this library

{{filter}}

Filter array of objects by fieldvalue

Example data

{
  "roller": [
    {
      "type": "BARN",
      "navn": "Barn1 Etternavn"
    },
    {
      "type": "BARN",
      "navn": "Barn2 Etternavn"
    },
    {
      "type": "FORELDRE",
      "navn": "Mor Etternavn"
    }
  ]
}

Params

• json {List} List of JSON values
• fieldname {String} Fieldname used for filtering
• value {String} Value to filter by
• returns {List} Filtered list

Example

{{#filter roller "type" "BARN" as |barn|}}
   <div>{{ barn.navn }}</div>
{{/filter}}

{{json_to_period}}

Format json with parameters fom, tom/til as period string

Example data

{
  "periode": {
    "fom": "2020-03-20",
    "tom": "2021-09-23"
  }
}

Params

• json {Periode} Object with fields fom and tom ortil
• returns {List} Formatted date (ex 20.03.2020 - 23.09.2021)

Example

{{json_to_period periode}}

Developing pdfgen-core

Build and run tests

./gradlew build

Publish to local maven repository

Run the following command ./gradlew publishToMavenLocal (or ./gradlew -t publishToMavenLocal if you want to enable autobuild on changes)

This will publish pdfgen-core to local maven repository with version local-build

You can then import pdfgen-core to your gradle project with

implementation("no.nav.pdfgen:pdfgen-core:local-build")

Upgrading the gradle wrapper

Find the newest version of gradle here: https://gradle.org/releases/ Then run this command:

./gradlew wrapper --gradle-version $gradleVersjon

👥 Contact

This project is currently maintained by the organisation @navikt.

If you need to raise an issue or question about this library, please create an issue here and tag it with the appropriate label.

For contact requests within the @navikt org, you can use the slack channel #pdfgen

If you need to contact anyone directly, please see contributors.

✏️ Contributing

To get started, please fork the repo and checkout a new branch. You can then build the library with the Gradle wrapper

./gradlew shadowJar

See more info in CONTRIBUTING.md