XmlAttrFilter.java

package com.hubspot.jinjava.lib.filter;

import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.Objects;

import org.apache.commons.lang3.BooleanUtils;
import org.apache.commons.lang3.StringEscapeUtils;
import org.apache.commons.lang3.StringUtils;

import com.hubspot.jinjava.doc.annotations.JinjavaDoc;
import com.hubspot.jinjava.doc.annotations.JinjavaParam;
import com.hubspot.jinjava.doc.annotations.JinjavaSnippet;
import com.hubspot.jinjava.interpret.JinjavaInterpreter;

@JinjavaDoc(
    value = "Create an HTML/XML attribute string based on the items in a dict.",
    params = {
        @JinjavaParam(value = "d", type = "dict", desc = "Dict to filter"),
        @JinjavaParam(value = "autospace", type = "boolean", defaultValue = "True", desc = "Automatically prepend a space in front of the item")
    },
    snippets = {
        @JinjavaSnippet(
            code = "{% set html_attributes = {'class': 'bold', 'id': 'sidebar'} %}\n" +
                "<div {{ html_attributes|xmlattr }}></div>")
    })
public class XmlAttrFilter implements Filter {

  @Override
  public String getName() {
    return "xmlattr";
  }

  @Override
  public Object filter(Object var, JinjavaInterpreter interpreter, String... args) {
    if (var == null || !Map.class.isAssignableFrom(var.getClass())) {
      return var;
    }

    @SuppressWarnings("unchecked")
    Map<String, Object> dict = (Map<String, Object>) var;
    List<String> attrs = new ArrayList<>();

    for (Map.Entry<String, Object> entry : dict.entrySet()) {
      attrs.add(new StringBuilder(entry.getKey())
          .append("=\"")
          .append(StringEscapeUtils.escapeXml10(Objects.toString(entry.getValue(), "")))
          .append("\"")
          .toString());
    }

    String space = " ";
    if (args.length > 0 && !BooleanUtils.toBoolean(args[0])) {
      space = "";
    }

    return space + StringUtils.join(attrs, "\n");
  }

}