go-corenlp

go-corenlp is a Golang wrapper for Stanford CoreNLP.

Install

Download and install it:

go get github.com/hironobu-s/go-corenlp

Make sure that you can run Stanford CoreNLP on command line:

java -cp "*" edu.stanford.nlp.pipeline.StanfordCoreNLP -h

Usage

A simple code for using go-corenlp is:

package main

import (
	"fmt"

	"github.com/hironobu-s/go-corenlp" // exposes "corenlp"
	"github.com/hironobu-s/go-corenlp/connector"
)

func main() {
	// sample text from https://stanfordnlp.github.io/CoreNLP/
	text := `President Xi Jinping of Chaina, on his first state visit to the United States, showed off his familiarity with American history and pop culture on Tuesday night.`

	// LocalExec connector is responsible to run Stanford CoreNLP process.
	c := connector.NewLocalExec(nil)
	c.ClassPath = "./corenlp/*" // set Java class path
	c.Annotators = []string{"tokenize", "ssplit", "pos"}

	// Annotate text
	doc, err := corenlp.Annotate(c, text)
	if err != nil {
		panic(err)
	}

	// Output words and pos
	for _, sentence := range doc.Sentences {
		for _, token := range sentence.Tokens {
			fmt.Printf("%s(%s)%s", token.Word, token.Pos, token.After)
		}
	}
}
	

Output:

President(NNP) Xi(NN) Jinping(NN) of(IN) Chaina(NNP),(,) on(IN) his(PRP$) first(JJ) state(NN) visit(NN) to(TO) the(DT) United(NNP) States(NNPS),(,) showed(VBD) off(IN) his(PRP$) familiarity(NN) with(IN) American(JJ) history(NN) and(CC) pop(NN) culture(NN) on(IN) Tuesday(NNP) night(NN).(.)

Handle an annotated documents

// Annotate text
doc, err := corenlp.Annotate(connector.NewLocalExec(nil), text)
if err != nil {
	panic(err)
}

// First sentence
sentence := doc.Sentences[0]

// RawParse contains text-based result of Parser annotator
fmt.Println(sentence.RawParse) // => (ROOT (S (NP (NP (NNP President)...

// Parse() returns go's struct of Parser annotator
parse, _ := sentence.Parse()
fmt.Printf("%v\n", parse.Pos) // => ROOT

// Tokenizer, PosTagger
for _, token := range sentence.Tokens {
	fmt.Printf("%s(%s)%s", token.Word, token.Pos, token.After)
}

// Dependencies
for _, dep := range sentence.Dependencies {
	fmt.Printf("%s => (%s) => %s\n", dep.GovernorGloss, dep.Dep, dep.DependentGloss)
}

Timeout

go-corenlp supports a timeout by using context.Context.

ctx, cancel := context.WithTimeout(context.Background(), 120*time.Second)
defer cancel()

c := connector.NewLocalExec(ctx)
doc, err := corenlp.Annotate(c, text)

Connect to CoreNLP server

To connect CoreNLP server, You may use HTTPClient provider.

ctx, cancel := context.WithTimeout(context.Background(), 120*time.Second)
defer cancel()

c := connector.NewHTTPClient(ctx, "http://127.0.0.1:9000/")
c.Username = "username"
c.Password = "password"

doc, err := corenlp.Annotate(c, text)

Parse json output

To use ParseOutput method, You can parse the output file which is generated by Stanford CoreNLP.

For example. If you run following command

java -cp "*" edu.stanford.nlp.pipeline.StanfordCoreNLP -annotators tokenize,ssplit -file input.txt --outputFormat json

The output file input.txt.json will be generated, So you can parse it as below.

rawjson, err := ioutil.ReadFile("input.txt.json")
if err != nil {
	panic(err)
}
doc, err := ParseOutput(rawjson)

LICENSE

MIT