com.github.jrubygradle.jem.Gem.java Source code

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Here is the source code for com.github.jrubygradle.jem.Gem.java

Source

package com.github.jrubygradle.jem;

import com.fasterxml.jackson.annotation.JsonProperty;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.DeserializationFeature;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.dataformat.yaml.YAMLFactory;

import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.util.List;

/**
 * Plain Old Java Object for an enumeration of metadata provided by a gem
 */
public class Gem {
    @JsonProperty
    public String name;

    @JsonProperty
    public Version version;

    @JsonProperty
    public String description;

    @JsonProperty
    public String platform;

    @JsonProperty
    public Object email;

    @JsonProperty
    public String homepage;

    @JsonProperty
    public List<String> authors;

    @JsonProperty
    public List<String> files;

    @JsonProperty(value = "test_files")
    public List<String> testFiles;

    @JsonProperty
    public List<String> executables;

    @JsonProperty
    public String bindir;

    @JsonProperty(value = "require_paths")
    public List<String> requirePaths;

    @JsonProperty
    public List<String> licenses;

    @JsonProperty(value = "specification_version")
    public Integer specificationVersion;

    @JsonProperty(value = "rubygems_version")
    public String rubygemsVersion;

    /**
     * Take the given argument and produce a {@code Gem} instance
     *
     * @param metadata a {@code java.lang.String}, a {@code java.io.File} or a {@code java.util.zip.GZIPInputStream}
     * @return constructed instance of Gem or null if we couldn't process arguments
     * @throws JsonProcessingException when the String provided is not JSON
     * @throws IOException when the File provided can not be properly read
     */
    public static Gem fromFile(Object metadata) throws JsonProcessingException, IOException {
        if (metadata instanceof String) {
            return createGemFromFile(new File((String) metadata));
        }
        if (metadata instanceof File) {
            return createGemFromFile((File) (metadata));
        }
        if (metadata instanceof InputStream) {
            return createGemFromInputStream((InputStream) (metadata));
        }

        return null;
    }

    /**
     * Output the gemspec stub for this file
     *
     * See: https://github.com/rubygems/rubygems/blob/165030689defe16680b7f336232db62024f49de4/lib/rubygems/specification.rb#L2422-L2512
     *
     * @return String representation of the computed .gemspec file
     * @throws JsonProcessingException if some attributes could not be properly serialized out to JSON
     */
    public String toRuby() throws JsonProcessingException {
        String[] specification = { "# -*- encoding: utf-8 -*-", "#",
                String.format("# stub: %s %s %s %s", name, version.version, platform,
                        join(requirePaths.toArray(new String[0]), "\0")),
                "#", "# NOTE: This specification was generated by `jem`",
                "#  <https://github.com/jruby-gradle/jem>", "", "Gem::Specification.new do |s|",
                "  s.name = " + sanitize(name), "  s.version = " + sanitize(version.version),
                "  s.description = " + sanitize(description), "  s.homepage = " + sanitize(homepage),
                "  s.authors = " + sanitize(authors), "  s.email = " + sanitize(email),
                "  s.licenses = " + sanitize(licenses), "", "  s.platform = " + sanitize(platform),
                "  s.require_paths = " + sanitize(requirePaths), "  s.executables = " + sanitize(executables),
                "  s.rubygems_version = " + sanitize(rubygemsVersion), "end", };
        return join(specification);
    }

    private String join(String[] segments) {
        return this.join(segments, System.getProperty("line.separator"));
    }

    private String join(String[] segments, String split) {
        StringBuilder builder = new StringBuilder();
        for (String segment : segments) {
            builder.append(String.format("%s%s", segment, split));
        }
        return builder.toString();
    }

    /**
     * Convert whatever object we're given into a safe (see: JSON) reprepsentation
     *
     * @param value Object to pass to Jackson to create a string representation of
     * @return String representation of the value parameter
     * @throws JsonProcessingException Exception when the value cannot be JSON serialized
     */
    protected String sanitize(Object value) throws JsonProcessingException {
        ObjectMapper mapper = new ObjectMapper();
        return mapper.writeValueAsString(value);
    }

    private static Gem createGemFromFile(File gemMetadataFile) throws JsonProcessingException, IOException {
        if (!gemMetadataFile.exists()) {
            return null;
        }
        return getYamlMapper().readValue(gemMetadataFile, Gem.class);
    }

    private static Gem createGemFromInputStream(InputStream gemMetadataStream)
            throws JsonProcessingException, IOException {
        return getYamlMapper().readValue(gemMetadataStream, Gem.class);
    }

    private static ObjectMapper getYamlMapper() {
        ObjectMapper mapper = new ObjectMapper(new YAMLFactory());
        mapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);
        return mapper;
    }
}