ListPlugins: Add support for filtering with prefix/substring/regex

Feature: Issue 6499
Change-Id: I7e54595dad56fc6a5e34bea55adee341077ad1fa

Documentation/rest-api-plugins.txt

@@ -110,6 +110,74 @@ Query the first plugin in the plugin list:
   }
 ----
 
+Prefix(p)::
+Limit the results to those plugins that start with the specified
+prefix.
++
+The match is case sensitive. May not be used together with `m` or `r`.
++
+List all plugins that start with `delete`:
++
+.Request
+----
+  GET /plugins/?p=delete HTTP/1.0
+----
++
+.Response
+----
+  HTTP/1.1 200 OK
+  Content-Disposition: attachment
+  Content-Type: application/json; charset=UTF-8
+
+  )]}'
+  {
+    "delete-project": {
+      "id": "delete-project",
+      "index_url": "plugins/delete-project/",
+      "version": "2.9-SNAPSHOT"
+    }
+  }
+----
++
+E.g. this feature can be used by suggestion client UI's to limit results.
+
+Regex(r)::
+Limit the results to those plugins that match the specified regex.
++
+Boundary matchers '^' and '$' are implicit. For example: the regex 'test.*' will
+match any plugins that start with 'test' and regex '.*test' will match any
+project that end with 'test'.
++
+The match is case sensitive. May not be used together with `m` or `p`.
++
+List all plugins that match regex `some.*plugin`:
++
+.Request
+----
+  GET /plugins/?r=some.*plugin HTTP/1.0
+----
++
+.Response
+----
+  HTTP/1.1 200 OK
+  Content-Disposition: attachment
+  Content-Type: application/json; charset=UTF-8
+
+  )]}'
+  {
+    "some-plugin": {
+      "id": "some-plugin",
+      "index_url": "plugins/some-plugin/",
+      "version": "2.9-SNAPSHOT"
+    },
+    "some-other-plugin": {
+      "id": "some-other-plugin",
+      "index_url": "plugins/some-other-plugin/",
+      "version": "2.9-SNAPSHOT"
+    }
+  }
+
+----
 
 Skip(S)::
 Skip the given number of plugins from the beginning of the list.
@@ -138,6 +206,33 @@ Query the second plugin in the plugin list:
   }
 ----
 
+Substring(m)::
+Limit the results to those plugins that match the specified substring.
++
+The match is case insensitive. May not be used together with `r` or `p`.
++
+List all plugins that match substring `project`:
++
+.Request
+----
+  GET /plugins/?m=project HTTP/1.0
+----
++
+.Response
+----
+  HTTP/1.1 200 OK
+  Content-Disposition: attachment
+  Content-Type: application/json; charset=UTF-8
+
+  )]}'
+  {
+    "delete-project": {
+      "id": "delete-project",
+      "index_url": "plugins/delete-project/",
+      "version": "2.9-SNAPSHOT"
+    }
+  }
+----
 
 [[install-plugin]]
 === Install Plugin

gerrit-acceptance-tests/src/test/java/com/google/gerrit/acceptance/api/plugin/PluginIT.java

@@ -17,6 +17,7 @@ package com.google.gerrit.acceptance.api.plugin;
 import static com.google.common.truth.Truth.assertThat;
 import static java.nio.charset.StandardCharsets.UTF_8;
 import static java.util.stream.Collectors.toList;
+import static org.junit.Assert.fail;
 
 import com.google.common.collect.ImmutableList;
 import com.google.gerrit.acceptance.AbstractDaemonTest;
@@ -27,6 +28,7 @@ import com.google.gerrit.extensions.api.plugins.PluginApi;
 import com.google.gerrit.extensions.api.plugins.Plugins.ListRequest;
 import com.google.gerrit.extensions.common.InstallPluginInput;
 import com.google.gerrit.extensions.common.PluginInfo;
+import com.google.gerrit.extensions.restapi.BadRequestException;
 import com.google.gerrit.extensions.restapi.MethodNotAllowedException;
 import com.google.gerrit.extensions.restapi.ResourceNotFoundException;
 import com.google.gerrit.extensions.restapi.RestApiException;
@@ -63,6 +65,24 @@ public class PluginIT extends AbstractDaemonTest {
     // With pagination
     assertPlugins(list().start(1).limit(2).get(), PLUGINS.subList(1, 3));
 
+    // With prefix
+    assertPlugins(list().prefix("plugin-b").get(), ImmutableList.of("plugin-b"));
+    assertPlugins(list().prefix("PLUGIN-").get(), ImmutableList.of());
+
+    // With substring
+    assertPlugins(list().substring("lugin-").get(), PLUGINS);
+    assertPlugins(list().substring("lugin-").start(1).limit(2).get(), PLUGINS.subList(1, 3));
+
+    // With regex
+    assertPlugins(list().regex(".*in-b").get(), ImmutableList.of("plugin-b"));
+    assertPlugins(list().regex("plugin-.*").get(), PLUGINS);
+    assertPlugins(list().regex("plugin-.*").start(1).limit(2).get(), PLUGINS.subList(1, 3));
+
+    // Invalid match combinations
+    assertBadRequest(list().regex(".*in-b").substring("a"));
+    assertBadRequest(list().regex(".*in-b").prefix("a"));
+    assertBadRequest(list().substring(".*in-b").prefix("a"));
+
     // Disable
     api = gApi.plugins().name("plugin-a");
     api.disable();
@@ -99,4 +119,13 @@ public class PluginIT extends AbstractDaemonTest {
     List<String> _actual = actual.stream().map(p -> p.id).collect(toList());
     assertThat(_actual).containsExactlyElementsIn(expected);
   }
+
+  private void assertBadRequest(ListRequest req) throws Exception {
+    try {
+      req.get();
+      fail("Expected BadRequestException");
+    } catch (BadRequestException e) {
+      // Expected
+    }
+  }
 }

gerrit-extension-api/src/main/java/com/google/gerrit/extensions/api/plugins/Plugins.java

@@ -35,6 +35,9 @@ public interface Plugins {
     private boolean all;
     private int limit;
     private int start;
+    private String substring;
+    private String prefix;
+    private String regex;
 
     public List<PluginInfo> get() throws RestApiException {
       Map<String, PluginInfo> map = getAsMap();
@@ -73,6 +76,33 @@ public interface Plugins {
     public int getStart() {
       return start;
     }
+
+    public ListRequest substring(String substring) {
+      this.substring = substring;
+      return this;
+    }
+
+    public String getSubstring() {
+      return substring;
+    }
+
+    public ListRequest prefix(String prefix) {
+      this.prefix = prefix;
+      return this;
+    }
+
+    public String getPrefix() {
+      return prefix;
+    }
+
+    public ListRequest regex(String regex) {
+      this.regex = regex;
+      return this;
+    }
+
+    public String getRegex() {
+      return regex;
+    }
   }
 
   /**

gerrit-server/src/main/java/com/google/gerrit/server/api/plugins/PluginsImpl.java

@@ -63,6 +63,9 @@ public class PluginsImpl implements Plugins {
         list.setAll(this.getAll());
         list.setStart(this.getStart());
         list.setLimit(this.getLimit());
+        list.setMatchPrefix(this.getPrefix());
+        list.setMatchSubstring(this.getSubstring());
+        list.setMatchRegex(this.getRegex());
         return list.apply();
       }
     };

gerrit-server/src/main/java/com/google/gerrit/server/plugins/ListPlugins.java

@@ -23,6 +23,7 @@ import com.google.gerrit.common.Nullable;
 import com.google.gerrit.common.data.GlobalCapability;
 import com.google.gerrit.extensions.annotations.RequiresCapability;
 import com.google.gerrit.extensions.common.PluginInfo;
+import com.google.gerrit.extensions.restapi.BadRequestException;
 import com.google.gerrit.extensions.restapi.RestReadView;
 import com.google.gerrit.extensions.restapi.TopLevelResource;
 import com.google.gerrit.extensions.restapi.Url;
@@ -31,9 +32,11 @@ import com.google.gson.reflect.TypeToken;
 import com.google.inject.Inject;
 import java.io.PrintWriter;
 import java.util.List;
+import java.util.Locale;
 import java.util.Map;
 import java.util.SortedMap;
 import java.util.TreeMap;
+import java.util.regex.Pattern;
 import java.util.stream.Stream;
 import org.kohsuke.args4j.Option;
 
@@ -45,6 +48,9 @@ public class ListPlugins implements RestReadView<TopLevelResource> {
   private boolean all;
   private int limit;
   private int start;
+  private String matchPrefix;
+  private String matchSubstring;
+  private String matchRegex;
 
   @Deprecated
   @Option(name = "--format", usage = "(deprecated) output format")
@@ -79,6 +85,31 @@ public class ListPlugins implements RestReadView<TopLevelResource> {
     this.start = start;
   }
 
+  @Option(
+    name = "--prefix",
+    aliases = {"-p"},
+    metaVar = "PREFIX",
+    usage = "match plugin prefix"
+  )
+  public void setMatchPrefix(String matchPrefix) {
+    this.matchPrefix = matchPrefix;
+  }
+
+  @Option(
+    name = "--match",
+    aliases = {"-m"},
+    metaVar = "MATCH",
+    usage = "match plugin substring"
+  )
+  public void setMatchSubstring(String matchSubstring) {
+    this.matchSubstring = matchSubstring;
+  }
+
+  @Option(name = "-r", metaVar = "REGEX", usage = "match plugin regex")
+  public void setMatchRegex(String matchRegex) {
+    this.matchRegex = matchRegex;
+  }
+
   @Inject
   protected ListPlugins(PluginLoader pluginLoader) {
     this.pluginLoader = pluginLoader;
@@ -94,20 +125,33 @@ public class ListPlugins implements RestReadView<TopLevelResource> {
   }
 
   @Override
-  public Object apply(TopLevelResource resource) {
+  public Object apply(TopLevelResource resource) throws BadRequestException {
     format = OutputFormat.JSON;
     return display(null);
   }
 
-  public SortedMap<String, PluginInfo> apply() {
+  public SortedMap<String, PluginInfo> apply() throws BadRequestException {
     format = OutputFormat.JSON;
     return display(null);
   }
 
-  public SortedMap<String, PluginInfo> display(@Nullable PrintWriter stdout) {
+  public SortedMap<String, PluginInfo> display(@Nullable PrintWriter stdout)
+      throws BadRequestException {
     SortedMap<String, PluginInfo> output = new TreeMap<>();
-    Stream<Plugin> s =
+    Stream<Plugin> s = Streams.stream(pluginLoader.getPlugins(all));
-        Streams.stream(pluginLoader.getPlugins(all)).sorted(comparing(Plugin::getName));
+    if (matchPrefix != null) {
+      checkMatchOptions(matchSubstring == null && matchRegex == null);
+      s = s.filter(p -> p.getName().startsWith(matchPrefix));
+    } else if (matchSubstring != null) {
+      checkMatchOptions(matchPrefix == null && matchRegex == null);
+      String substring = matchSubstring.toLowerCase(Locale.US);
+      s = s.filter(p -> p.getName().toLowerCase(Locale.US).contains(substring));
+    } else if (matchRegex != null) {
+      checkMatchOptions(matchPrefix == null && matchSubstring == null);
+      Pattern pattern = Pattern.compile(matchRegex);
+      s = s.filter(p -> pattern.matcher(p.getName()).matches());
+    }
+    s = s.sorted(comparing(Plugin::getName));
     if (start > 0) {
       s = s.skip(start);
     }
@@ -148,6 +192,12 @@ public class ListPlugins implements RestReadView<TopLevelResource> {
     return null;
   }
 
+  private void checkMatchOptions(boolean cond) throws BadRequestException {
+    if (!cond) {
+      throw new BadRequestException("specify exactly one of p/m/r");
+    }
+  }
+
   public static PluginInfo toPluginInfo(Plugin p) {
     String id;
     String version;