TileController.java

/*
 * Copyright 2024 Global Crop Diversity Trust
 *
 * 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.gringlobal.api.v2.impl;

import java.io.IOException;
import java.util.concurrent.ExecutionException;

import org.gringlobal.service.AccessionService;
import org.gringlobal.service.ShortFilterService;
import org.gringlobal.service.filter.AccessionFilter;
import org.gringlobal.util.ColorUtil;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpStatus;
import org.springframework.http.MediaType;
import org.springframework.http.ResponseEntity;
import org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;

import lombok.extern.slf4j.Slf4j;

/**
 * This is not an API controller, it's accessible to anonymous users.
 */
@Controller
@Slf4j
public class TileController {

	@Autowired
	private AccessionService accessionService;

	@Autowired
	private ShortFilterService shortFilterService;

	@Autowired
	private ThreadPoolTaskExecutor taskExecutor;

	@RequestMapping(value = "/tile/a/{zoom:\\d+}/{x:\\d+}/{y:\\d+}", produces = MediaType.IMAGE_PNG_VALUE)
	public ResponseEntity<?> tile(@RequestParam(value = "f", required = true) String filterCode,
		@RequestParam(value = "color", required = false) String color,
		@PathVariable("x") int x, @PathVariable("y") int y, @PathVariable("zoom") int zoom) throws IOException, ExecutionException, InterruptedException {
		return taskExecutor.submit(() -> {
			try {
				AccessionFilter appliedFilters = shortFilterService.filterByCode(filterCode, AccessionFilter.class);

				byte[] image = accessionService.getTile(appliedFilters, zoom, x, y);;
				image = ColorUtil.changeColor("#578218", color, image); // #578218 is used by resources/tileserver/accessionDotX.png

				// HTTP maxAge
				int maxAge;
				if (zoom < 8) {
					maxAge = 60 * 60; // 1 hr
				} else {
					maxAge = 60 * 5; // 5 min
				}
				return ResponseEntity.status(HttpStatus.OK)
					.header(HttpHeaders.CACHE_CONTROL, "max-age=" + maxAge + ", s-maxage=" + maxAge + ", public, no-transform")
					.contentType(MediaType.IMAGE_PNG)
					.header(HttpHeaders.ACCESS_CONTROL_ALLOW_ORIGIN, "*")
					.contentLength(image.length)
					.body(image);
			} catch (Exception e) {
				log.warn("Exception in tile request processing", e);
				return ResponseEntity.badRequest().build();
			}
		}).get();
	}
}