Datacite submission & Orcid authority (#665)

* A DataCite submission workflow

and coresponding updates in the dissemination crosswalk.
Add new metadata fields via the registry-loader
```
/dspace/bin/dspace registry-loader -metadata \
/dspace/config/registries/datacite.xml
```

There's a lot of TODOs - ideas for future improvements, or where the
mapping isn't ideal.

* ORCID authority which stores the ids in the authority column

easier to access in ui/dissemination...
At the moment only the getLabel calls are cached.

dspace-api/src/main/java/org/dspace/content/authority/SimpleORCIDAuthority.java

@@ -0,0 +1,164 @@
+/**
+ * The contents of this file are subject to the license and copyright
+ * detailed in the LICENSE and NOTICE files at the root of the source
+ * tree and available online at
+ *
+ * http://www.dspace.org/license/
+ */
+package org.dspace.content.authority;
+
+import java.util.List;
+import java.util.stream.Collectors;
+
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+import org.dspace.external.CachingOrcidRestConnector;
+import org.dspace.external.provider.orcid.xml.ExpandedSearchConverter;
+import org.dspace.utils.DSpace;
+
+
+/**
+ * ChoiceAuthority using the ORCID API.
+ * It uses the orcid as the authority value and thus is simpler to use then the * SolrAuthority.
+ */
+public class SimpleORCIDAuthority implements ChoiceAuthority {
+
+    private static final Logger log = LogManager.getLogger(SimpleORCIDAuthority.class);
+
+    private String pluginInstanceName;
+    private final CachingOrcidRestConnector orcidRestConnector = new DSpace().getServiceManager().getServiceByName(
+            "CachingOrcidRestConnector", CachingOrcidRestConnector.class);
+    private static final int maxResults = 100;
+
+    /**
+     * Get all values from the authority that match the preferred value.
+     * Note that the offering was entered by the user and may contain
+     * mixed/incorrect case, whitespace, etc so the plugin should be careful
+     * to clean up user data before making comparisons.
+     * <p>
+     * Value of a "Name" field will be in canonical DSpace person name format,
+     * which is "Lastname, Firstname(s)", e.g. "Smith, John Q.".
+     * <p>
+     * Some authorities with a small set of values may simply return the whole
+     * set for any sample value, although it's a good idea to set the
+     * defaultSelected index in the Choices instance to the choice, if any,
+     * that matches the value.
+     *
+     * @param text   user's value to match
+     * @param start  choice at which to start, 0 is first.
+     * @param limit  maximum number of choices to return, 0 for no limit.
+     * @param locale explicit localization key if available, or null
+     * @return a Choices object (never null).
+     */
+    @Override
+    public Choices getMatches(String text, int start, int limit, String locale) {
+        log.debug("getMatches: " + text + ", start: " + start + ", limit: " + limit + ", locale: " + locale);
+        if (text == null || text.trim().isEmpty()) {
+            return new Choices(true);
+        }
+
+        start = Math.max(start, 0);
+        if (limit < 1 || limit > maxResults) {
+            limit = maxResults;
+        }
+
+        ExpandedSearchConverter.Results search = orcidRestConnector.search(text, start, limit);
+        List<Choice> choices = search.results().stream()
+                .map(this::toChoice)
+                .collect(Collectors.toList());
+
+
+        int confidence = !search.isOk() ? Choices.CF_FAILED :
+                         choices.isEmpty() ? Choices.CF_NOTFOUND :
+                         choices.size() == 1 ? Choices.CF_UNCERTAIN
+                                             : Choices.CF_AMBIGUOUS;
+        int total = search.numFound().intValue();
+        return new Choices(choices.toArray(new Choice[0]), start, total,
+                confidence, total > (start + limit));
+    }
+
+    /**
+     * Get the single "best" match (if any) of a value in the authority
+     * to the given user value.  The "confidence" element of Choices is
+     * expected to be set to a meaningful value about the circumstances of
+     * this match.
+     * <p>
+     * This call is typically used in non-interactive metadata ingest
+     * where there is no interactive agent to choose from among options.
+     *
+     * @param text   user's value to match
+     * @param locale explicit localization key if available, or null
+     * @return a Choices object (never null) with 1 or 0 values.
+     */
+    @Override
+    public Choices getBestMatch(String text, String locale) {
+        log.debug("getBestMatch: " + text);
+        Choices matches = getMatches(text, 0, 1, locale);
+        if (matches.values.length != 0 && !matches.values[0].value.equalsIgnoreCase(text)) {
+            // novalue
+            matches = new Choices(false);
+        }
+        return matches;
+    }
+
+    /**
+     * Get the canonical user-visible "label" (i.e. short descriptive text)
+     * for a key in the authority.  Can be localized given the implicit
+     * or explicit locale specification.
+     * <p>
+     * This may get called many times while populating a Web page so it should
+     * be implemented as efficiently as possible.
+     *
+     * @param key    authority key known to this authority.
+     * @param locale explicit localization key if available, or null
+     * @return descriptive label - should always return something, never null.
+     */
+    @Override
+    public String getLabel(String key, String locale) {
+        log.debug("getLabel: " + key);
+        String label = orcidRestConnector.getLabel(key);
+        return label != null ? label : key;
+    }
+
+    /**
+     * Get the instance's particular name.
+     * Returns the name by which the class was chosen when
+     * this instance was created.  Only works for instances created
+     * by <code>PluginService</code>, or if someone remembers to call <code>setPluginName.</code>
+     * <p>
+     * Useful when the implementation class wants to be configured differently
+     * when it is invoked under different names.
+     *
+     * @return name or null if not available.
+     */
+    @Override
+    public String getPluginInstanceName() {
+        return pluginInstanceName;
+    }
+
+    /**
+     * Set the name under which this plugin was instantiated.
+     * Not to be invoked by application code, it is
+     * called automatically by <code>PluginService.getNamedPlugin()</code>
+     * when the plugin is instantiated.
+     *
+     * @param name -- name used to select this class.
+     */
+    @Override
+    public void setPluginInstanceName(String name) {
+        this.pluginInstanceName = name;
+    }
+
+    private Choice toChoice(ExpandedSearchConverter.Result result) {
+        Choice c = new Choice(result.authority(), result.value(), result.label());
+        //add orcid to extras so it's shown
+        c.extras.put("orcid", result.authority());
+        // add the value to extra information only if it is present
+        //in dspace-angular the extras are keys for translation form.other-information.<extra>
+        result.creditName().ifPresent(val -> c.extras.put("credit-name", val));
+        result.otherNames().ifPresent(val -> c.extras.put("other-names", val));
+        result.institutionNames().ifPresent(val -> c.extras.put("institution", val));
+
+        return c;
+    }
+}

dspace-api/src/main/java/org/dspace/external/CachingOrcidRestConnector.java

@@ -0,0 +1,222 @@
+/**
+ * The contents of this file are subject to the license and copyright
+ * detailed in the LICENSE and NOTICE files at the root of the source
+ * tree and available online at
+ *
+ * http://www.dspace.org/license/
+ */
+package org.dspace.external;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.net.URI;
+import java.net.URLEncoder;
+import java.net.http.HttpClient;
+import java.net.http.HttpRequest;
+import java.net.http.HttpResponse;
+import java.nio.charset.StandardCharsets;
+import java.time.Duration;
+import java.util.Optional;
+import java.util.regex.Pattern;
+
+import org.apache.commons.lang.StringUtils;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+import org.dspace.external.provider.orcid.xml.ExpandedSearchConverter;
+import org.dspace.services.ConfigurationService;
+import org.dspace.utils.DSpace;
+import org.json.JSONObject;
+import org.springframework.cache.annotation.Cacheable;
+
+/**
+ * A different implementation of the communication with the ORCID API.
+ * The API returns no-cache headers, we use @Cacheable to cache the labels (id->name) for some time.
+ * Originally the idea was to reuse the OrcidRestConnector, but in the end that just wraps apache http client.
+ */
+public class CachingOrcidRestConnector {
+    private static final Logger log = LogManager.getLogger(CachingOrcidRestConnector.class);
+
+    private String apiURL;
+    // Access tokens are long-lived ~ 20years, don't bother with refreshing
+    private volatile String _accessToken;
+    private final ExpandedSearchConverter converter = new ExpandedSearchConverter();
+
+    private static final Pattern p = Pattern.compile("^\\p{Alpha}+", Pattern.UNICODE_CHARACTER_CLASS);
+    private static final String edismaxParams =  "&defType=edismax&qf=" +
+            URLEncoder.encode( "family-name^4.0 credit-name^3.0 other-names^2.0 text", StandardCharsets.UTF_8);
+
+    private final HttpClient httpClient = HttpClient
+            .newBuilder()
+            .connectTimeout( Duration.ofSeconds(5))
+            .build();
+
+    /*
+     * We basically need to obtain the access token only once, but there is no guarantee this will succeed. The
+     * failure shouldn't be fatal, so we'll try again next time.
+     */
+    private Optional<String> init() {
+        if (_accessToken == null) {
+            synchronized (CachingOrcidRestConnector.class) {
+                if (_accessToken == null) {
+                    log.info("Initializing Orcid connector");
+                    ConfigurationService configurationService = new DSpace().getConfigurationService();
+                    String clientSecret = configurationService.getProperty("orcid.application-client-secret");
+                    String clientId = configurationService.getProperty("orcid.application-client-id");
+                    String OAUTHUrl = configurationService.getProperty("orcid.token-url");
+
+                    try {
+                        _accessToken = getAccessToken(clientSecret, clientId, OAUTHUrl);
+                    } catch (Exception e) {
+                        log.error("Error during initialization of the Orcid connector", e);
+                    }
+                }
+            }
+        }
+        return Optional.ofNullable(_accessToken);
+    }
+
+    /**
+     * Set the URL of the ORCID API
+     * @param apiURL
+     */
+    public void setApiURL(String apiURL) {
+        this.apiURL = apiURL;
+    }
+
+    /**
+     * Search the ORCID API
+     *
+     * The query is passed to the ORCID API as is, except when it contains just 'unicode letters'.
+     * In that case, we try to be smart and turn it into edismax query with wildcard.
+     *
+     * @param query - the search query
+     * @param start - initial offset when paging results
+     * @param limit - maximum number of results to return
+     * @return the results
+     */
+    public ExpandedSearchConverter.Results search(String query, int start, int limit) {
+        String extra;
+        // if query contains just 'unicode letters'; try to be smart and turn it into edismax query with wildcard
+        if (p.matcher(query).matches()) {
+            query += " || " + query + "*";
+            extra = edismaxParams;
+        } else {
+            extra = "";
+        }
+        final String searchPath = String.format("expanded-search?q=%s&start=%s&rows=%s%s", URLEncoder.encode(query,
+                StandardCharsets.UTF_8), start, limit, extra);
+
+        return init().map(token -> {
+            try (InputStream inputStream = httpGet(searchPath, token)) {
+                return converter.convert(inputStream);
+            } catch (IOException e) {
+                log.error("Error during search", e);
+                return ExpandedSearchConverter.ERROR;
+            }
+        }).orElse(ExpandedSearchConverter.ERROR);
+    }
+
+    /**
+     * Get the label for an ORCID, ideally the name of the person.
+     *
+     * Null is:
+     *  - either an error -> won't be cached,
+     *  - or it means no result, which'd be odd provided we get here with a valid orcid -> not caching should be ok
+     *
+     * @param orcid the id you are looking for
+     * @return the label or null in case nothing found/error
+     */
+    @Cacheable(cacheNames = "orcid-labels", unless = "#result == null")
+    public String getLabel(String orcid) {
+        log.debug("getLabel: " + orcid);
+        // in theory, we could use orcid.org/v3.0/<ORCID>/personal-details, but didn't want to write another converter
+        ExpandedSearchConverter.Results search = search("orcid:" + orcid, 0, 1);
+        if (search.isOk() && search.numFound() > 0) {
+            return search.results().get(0).label();
+        }
+        return null;
+    }
+
+    protected String getAccessToken(String clientSecret, String clientId, String OAUTHUrl) {
+        if (StringUtils.isNotBlank(clientSecret)
+                && StringUtils.isNotBlank(clientId)
+                && StringUtils.isNotBlank(OAUTHUrl)) {
+            String authenticationParameters =
+                    String.format("client_id=%s&client_secret=%s&scope=/read-public&grant_type=client_credentials",
+                            clientId, clientSecret);
+
+            HttpRequest request = HttpRequest.newBuilder()
+                    .uri(java.net.URI.create(OAUTHUrl))
+                    .POST(HttpRequest.BodyPublishers.ofString(authenticationParameters))
+                    .timeout(Duration.ofSeconds(5))
+                    .header("Accept", "application/json")
+                    .header("Content-Type", "application/x-www-form-urlencoded")
+                    .build();
+
+            try {
+                HttpResponse<String> response = httpClient.send(request, HttpResponse.BodyHandlers.ofString());
+                if (isSuccess(response)) {
+                    JSONObject responseObject = new JSONObject(response.body());
+                    return responseObject.getString("access_token");
+                } else {
+                    log.error("Error during initialization of the Orcid connector, status code: "
+                            + response.statusCode());
+                    throw new RuntimeException("Error during initialization of the Orcid connector, status code: "
+                            + response.statusCode());
+                }
+            } catch (IOException | InterruptedException e) {
+                log.error("Error during initialization of the Orcid connector", e);
+                throw new RuntimeException(e);
+            }
+        } else {
+            log.error("Missing configuration for Orcid connector");
+            throw new RuntimeException("Missing configuration for Orcid connector");
+        }
+    }
+
+    private InputStream httpGet(String path, String accessToken) throws IOException {
+        String trimmedPath = path.replaceFirst("^/+", "").replaceFirst("/+$", "");
+
+        String fullPath = apiURL + '/' + trimmedPath;
+
+        HttpRequest request = HttpRequest.newBuilder()
+                .uri(URI.create(fullPath))
+                .timeout(Duration.ofSeconds(5))
+                .header("Content-Type", "application/vnd.orcid+xml")
+                .header("Authorization", "Bearer " + accessToken)
+                .build();
+
+        try {
+            HttpResponse<InputStream> response = httpClient.send(request, HttpResponse.BodyHandlers.ofInputStream());
+            if (isSuccess(response)) {
+                return response.body();
+            } else {
+                log.error("Error in rest connector for path: " + fullPath + ", status code: " + response.statusCode());
+                throw new UnexpectedStatusException("Error in rest connector for path: "
+                        + fullPath + ", status code: " + response.statusCode());
+            }
+        } catch (UnexpectedStatusException e) {
+            throw e;
+        } catch (IOException | InterruptedException e) {
+            log.error("Error in rest connector for path: " + fullPath, e);
+            throw new RuntimeException(e);
+        }
+    }
+
+    private boolean isSuccess(HttpResponse<?> response) {
+        return response.statusCode() >= 200 && response.statusCode() < 300;
+    }
+
+    private static class UnexpectedStatusException extends IOException {
+        public UnexpectedStatusException(String message) {
+            super(message);
+        }
+    }
+
+    //Just for testing
+    protected void forceAccessToken(String accessToken) {
+        synchronized (CachingOrcidRestConnector.class) {
+            this._accessToken = accessToken;
+        }
+    }
+}