Pdf Generator Microservice

A REST-accessible self-contained fat-jar micro-service that creates PDFs from XHTML templates, substituting placeholder text in the template with caller-supplied values.

Building and running

Build command (includes running unit and integration tests):

./gradlew build

Run locally:

./gradlew run

Running deployable fat jar (after building):

java -jar pdfGenerator.jar (in the build/libs directory)

Configuration parameters can be supplied via environment variables, e.g.:

PORT=4567 ./gradlew run
PORT=4567 java -jar pdfGenerator.jar

The service endpoint defaults to local port 8080.

Development notes

Developed in Java 8 with additional Lombok support. Unit and Integration tests are written in Groovy and Spock. The build system used is Gradle.

Google Guice provides a Dependency Injection framework, the HTTP REST service is provided by the Java Spark Framework, and the PDF Renderer uses the Flying Saucer library.

Templates are currently stored as *.html resources within the service, but this will be updated in the near future to obtain templates from a MongoDB database instead.

Deployment notes

The service currently runs stand-alone (it will require access to a MongoDB database instance in the future), and is configurable via environment parameters:

DEBUG_LOG=true (defaults to false for INFO level logging, set to true for DEBUG level)

Usage notes

To generate a PDF, issue a POST request to /generate that include the template name and substitution values, e.g.:

POST /generate HTTP/1.1
Host: localhost:8080

{
	"templateName": "helloWorld",
	"values": {
		"SALUTATION": "Mr",
		"FORENAME": "John",
		"SURNAME": "Smith"
	}
}

The service will return the PDF binary object as a JSON array of Byte values, e.g. [37, 80, 68, 70, 45, 49 ..

Debug mode

When the service is instantiated in Debug mode e.g. DEBUG_LOG=true java -jar pdfGenerator.jar, a browser-accessible GET endpoint for PDF generation is made available at /debug which can be used to test a template and value substitution directly.

E.g. browse to http://localhost:8080/debug/helloWorld?SALUTATION=Mr&FORENAME=John&SURNAME=Smith&CASE_NUMBER=ABC12345&ADDRESS_LINE_1=10%20High%20Street&ADDRESS_LINE_2=Sometown&ADDRESS_LINE_3=Shiresville&DD_MMM_YYYY=10th%20June%202017 for a demonstration if the service is running locally on your machine with default settings.

Template creation

To create or modify new templates, load or create e.g. a Word Document in LibreOffice, and alter as necessary to include PLACE_HOLDER text which will be substituted in generated PDFs.

Then choose File | Export.. from the menu, and export in XHTML .html format. This new template should then be made available to the PDF Generator service by storaing in the src/main/resources/templates directory.

Building and running with Docker

Build Docker Image ./buildDocker.sh
Run Docker Container docker run -d -p 8080:8080 --name pdfgenerator pdfgenerator

whi-tw/pdf-generator