LinkCreator.java

/*
Copyright (c) 2010-2016 Red Hat, Inc.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

  http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

package org.ovirt.engine.api.utils;

import java.util.List;

import org.apache.commons.lang.StringUtils;
import org.ovirt.engine.api.model.DetailedLink;
import org.ovirt.engine.api.model.Link;
import org.ovirt.engine.api.model.LinkCapabilities;
import org.ovirt.engine.api.model.Parameter;
import org.ovirt.engine.api.model.ParametersSet;
import org.ovirt.engine.api.model.Request;
import org.ovirt.engine.api.model.Url;

public class LinkCreator {
    private static final String SEARCH_RELATION = "/search";
    private static final String SEARCH_TEMPLATE = "?search={query}";
    private static final String MATRIX_PARAMETER_TEMPLATE = ";%s={%s}";

    /**
     * Create a search link with the given parameters
     *
     * @param url the url
     * @param rel the link to add
     * @param flags flags for this link, e.g: 'searchable'
     * @return the link the was created
     */
    public static DetailedLink createLink(String url, String rel, LinkFlags flags) {
        return createLink(url, rel, flags, new ParametersSet());
    }

    /**
     * Create a search link with the given parameters
     *
     * @param url the url
     * @param rel the link to add
     * @param flags flags for this link, e.g: 'searchable'
     * @param params url parameters
     * @return the link the was created
     */
    public static DetailedLink createLink(String url, String rel, LinkFlags flags, ParametersSet params) {
        DetailedLink link = new DetailedLink();
        link.setRel(rel);
        link.setHref(combine(url, rel));
        if (flags == LinkFlags.SEARCHABLE) {
            LinkCapabilities capabilities = new LinkCapabilities();
            capabilities.setSearchable(true);
            link.setLinkCapabilities(capabilities);
        }
        link.setRequest(new Request());
        link.getRequest().setUrl(new Url());
        link.getRequest().getUrl().getParametersSets().add(params);
        return link;
    }

    /**
     * Create a search link with the given parameters
     *
     * @param url the url
     * @param rel the link to add
     * @param params url parameters
     * @return the link the was created
     */
    public static Link createLink(String url, String rel, List<ParametersSet> params) {
        Link link = new Link();
        link.setRel(rel + SEARCH_RELATION);
        link.setHref(combine(url, params) + SEARCH_TEMPLATE);
        return link;
    }

    public static Link createLink(String url, String rel) {
        Link link = new Link();
        link.setRel(rel);
        link.setHref(url);
        return link;
    }

    /**
     * Create a search link with the given parameters
     * @param url the url
     * @param rel the link to add
     * @return link with search
     */
    public static Link createSearchLink(String url, String rel) {
        Link link = new Link();
        link.setRel(rel + SEARCH_RELATION);
        link.setHref(combine(url, rel) + SEARCH_TEMPLATE);
        return link;
    }

    /**
     * Combine head and tail portions of a URI path.
     *
     * @param head the path head
     * @param tail the path tail
     * @return the combined head and tail
     */
    public static String combine(String head, String tail) {
        return StringUtils.removeEnd(head, "/") + "/" + StringUtils.removeStart(tail, "/");
    }

    /**
     * Combine URL params to URI path.
     *
     * @param head the path head
     * @param params the URL params to append
     * @return the combined head and params
     */
    public static String combine(String head, List<ParametersSet> params) {
        StringBuilder combined_params = new StringBuilder();
        if (params != null) {
           for (ParametersSet ps : params) {
               for (Parameter param : ps.getParameters()) {
                   combined_params.append(String.format(MATRIX_PARAMETER_TEMPLATE, param.getName(), param.getValue()));
              }
           }
        }
        combined_params.insert(0, head);
        return combined_params.toString();
    }

    /**
     * Used to specify link options
     */
    public enum LinkFlags { NONE, SEARCHABLE; }
}