Remove /type REST API projections

Clients can acquire the MIME type from the content using the
X-FYI-Content-Type header. If only the headers are necessary,
callers should use HEAD instead of GET.

Change-Id: I3be4aeb009fabb7899c6018ed232ef9c7fd347cb

Documentation/rest-api-changes.txt

@@ -1408,8 +1408,16 @@ Retrieves content of a file from a change edit.
   GET /changes/myProject~master~I8473b95934b5732ac55d26311a706c9c2bde9940/edit/foo HTTP/1.0
 ----
 
-The content of the file is returned as text encoded inside base64. When
+The content of the file is returned as text encoded inside base64.
-specified file was deleted in the change edit "`204 No Content`" is returned.
+The Content-Type header will always be `text/plain` reflecting the
+outer base64 encoding. A Gerrit-specific `X-FYI-Content-Type` header
+can be examined to find the server detected content type of the file.
+
+When the specified file was deleted in the change edit
+"`204 No Content`" is returned.
+
+If only the content type is required, callers should use HEAD to
+avoid downloading the encoded file contents.
 
 .Response
 ----
@@ -1417,33 +1425,11 @@ specified file was deleted in the change edit "`204 No Content`" is returned.
   Content-Disposition: attachment
   Content-Type: text/plain; charset=ISO-8859-1
   X-FYI-Content-Encoding: base64
+  X-FYI-Content-Type: text/xml
 
   RnJvbSA3ZGFkY2MxNTNmZGVhMTdhYTg0ZmYzMmE2ZTI0NWRiYjY...
 ----
 
-[[get-edit-file-mime-type]]
-=== Retrieve file content MIME type from Change Edit
---
-'GET /changes/link:#change-id[\{change-id\}]/edit/path%2fto%2ffile/type
---
-
-Retrieves content MIME type of a file from a change edit.
-
-.Request
-----
-  GET /changes/myProject~master~I8473b95934b5732ac55d26311a706c9c2bde9940/edit/foo%2fbar%2fbaz%2fqux.txt/type HTTP/1.0
-----
-
-.Response
-----
-  HTTP/1.1 200 OK
-  Content-Disposition: attachment
-  Content-Type: application/json; charset=UTF-8
-
-  )]}'
-  "text/plain"
-----
-
 [[get-edit-message]]
 === Retrieve commit message from Change Edit or current patch set of the change
 --
@@ -2789,43 +2775,25 @@ Gets the content of a file from a certain revision.
   GET /changes/myProject~master~I8473b95934b5732ac55d26311a706c9c2bde9940/revisions/674ac754f91e64a0efb8087e59a176484bd534d1/files/gerrit-server%2Fsrc%2Fmain%2Fjava%2Fcom%2Fgoogle%2Fgerrit%2Fserver%2Fproject%2FRefControl.java/content HTTP/1.0
 ----
 
-The content is returned as base64 encoded string.
+The content is returned as base64 encoded string.  The HTTP response
+Content-Type is always `text/plain`, reflecting the base64 wrapping.
+A Gerrit-specific `X-FYI-Content-Type` header is returned describing
+the server detected content type of the file.
+
+If only the content type is required, callers should use HEAD to
+avoid downloading the encoded file contents.
 
 .Response
 ----
   HTTP/1.1 200 OK
   Content-Disposition: attachment
-  Content-Type: text/plain; charset=UTF-8
+  Content-Type: text/plain; charset=ISO-8859-1
+  X-FYI-Content-Encoding: base64
+  X-FYI-Content-Type: text/xml
 
   Ly8gQ29weXJpZ2h0IChDKSAyMDEwIFRoZSBBbmRyb2lkIE9wZW4gU291cmNlIFByb2plY...
 ----
 
-[[get-content-type]]
-=== Get Content MIME Type
---
-'GET /changes/link:#change-id[\{change-id\}]/revisions/link:#revision-id[\{revision-id\}]/files/link:#file-id[\{file-id\}]/type'
---
-
-Gets the content MIME type of a file from a certain revision.
-
-.Request
-----
-  GET /changes/myProject~master~I8473b95934b5732ac55d26311a706c9c2bde9940/revisions/674ac754f91e64a0efb8087e59a176484bd534d1/files/readme.txt/type HTTP/1.0
-----
-
-The content MIME type is returned as string. The content type for the commit
-message (`/COMMIT_MSG`) is always returned as "text/plain".
-
-.Response
-----
-  HTTP/1.1 200 OK
-  Content-Disposition: attachment
-  Content-Type: application/json; charset=UTF-8
-
-  )]}'
-  "text/plain"
-----
-
 [[get-diff]]
 === Get Diff
 --

gerrit-acceptance-tests/src/test/java/com/google/gerrit/acceptance/edit/ChangeEditIT.java

@@ -508,18 +508,6 @@ public class ChangeEditIT extends AbstractDaemonTest {
         .isEqualTo(StringUtils.newStringUtf8(CONTENT_NEW2));
   }
 
-  @Test
-  public void getFileContentTypeRest() throws Exception {
-    Put.Input in = new Put.Input();
-    in.content = RestSession.newRawInput(CONTENT_NEW);
-    assertThat(adminSession.putRaw(urlEditFile(), in.content).getStatusCode())
-        .isEqualTo(SC_NO_CONTENT);
-    RestResponse r = adminSession.get(urlEditFileContentType());
-    assertThat(r.getStatusCode()).isEqualTo(SC_OK);
-    String res = newGson().fromJson(r.getReader(), String.class);
-    assertThat(res).isEqualTo("application/octet-stream");
-  }
-
   @Test
   public void getFileNotFoundRest() throws Exception {
     assertThat(modifier.createEdit(change, ps)).isEqualTo(RefUpdate.Result.NEW);
@@ -672,13 +660,6 @@ public class ChangeEditIT extends AbstractDaemonTest {
         + FILE_NAME;
   }
 
-  private String urlEditFileContentType() {
-    return urlEdit()
-        + "/"
-        + FILE_NAME
-        + "/type";
-  }
-
   private String urlGetFiles() {
     return urlEdit()
         + "?list";

gerrit-server/src/main/java/com/google/gerrit/server/change/ChangeEdits.java

@@ -511,23 +511,4 @@ public class ChangeEdits implements
       throw new ResourceNotFoundException();
     }
   }
-
-  @Singleton
-  public static class GetType implements RestReadView<ChangeEditResource> {
-    private final FileContentUtil fileContentUtil;
-
-    @Inject
-    GetType(FileContentUtil fileContentUtil) {
-      this.fileContentUtil = fileContentUtil;
-    }
-
-    @Override
-    public String apply(ChangeEditResource rsrc)
-        throws ResourceNotFoundException, IOException {
-      return fileContentUtil.getContentType(
-          rsrc.getControl().getProjectControl().getProjectState(),
-          rsrc.getChangeEdit().getEditCommit(),
-          rsrc.getPath());
-    }
-  }
 }

gerrit-server/src/main/java/com/google/gerrit/server/change/FileContentUtil.java

@@ -119,43 +119,6 @@ public class FileContentUtil {
     return result;
   }
 
-  public String getContentType(ProjectState project, ObjectId rev,
-      String path) throws ResourceNotFoundException, IOException {
-    Repository repo = openRepository(project);
-    try {
-      RevWalk rw = new RevWalk(repo);
-      try {
-        ObjectReader reader = rw.getObjectReader();
-        RevCommit commit = rw.parseCommit(rev);
-        TreeWalk tw = TreeWalk.forPath(reader, path, commit.getTree());
-        if (tw == null) {
-          throw new ResourceNotFoundException();
-        }
-
-        org.eclipse.jgit.lib.FileMode mode = tw.getFileMode(0);
-        if (mode == org.eclipse.jgit.lib.FileMode.GITLINK) {
-          return X_GIT_GITLINK;
-        } else if (mode == org.eclipse.jgit.lib.FileMode.SYMLINK) {
-          return X_GIT_SYMLINK;
-        }
-
-        ObjectLoader blob = reader.open(tw.getObjectId(0), OBJ_BLOB);
-        byte[] raw;
-        try {
-          raw = blob.getCachedBytes(MAX_SIZE);
-        } catch (LargeObjectException e) {
-          raw = null;
-        }
-        String type = registry.getMimeType(path, raw).toString();
-        return resolveContentType(project, path, FileMode.FILE, type);
-      } finally {
-        rw.release();
-      }
-    } finally {
-      repo.close();
-    }
-  }
-
   public static String resolveContentType(ProjectState project, String path,
       FileMode fileMode, String mimeType) {
     switch (fileMode) {

gerrit-server/src/main/java/com/google/gerrit/server/change/GetContentType.java

@@ -1,48 +0,0 @@
-// Copyright (C) 2014 The Android Open Source Project
-//
-// 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 com.google.gerrit.server.change;
-
-import com.google.gerrit.extensions.restapi.ResourceNotFoundException;
-import com.google.gerrit.extensions.restapi.RestReadView;
-import com.google.gerrit.reviewdb.client.Patch;
-import com.google.inject.Inject;
-import com.google.inject.Singleton;
-
-import org.eclipse.jgit.lib.ObjectId;
-
-import java.io.IOException;
-
-@Singleton
-public class GetContentType implements RestReadView<FileResource> {
-  private final FileContentUtil fileContentUtil;
-
-  @Inject
-  GetContentType(FileContentUtil fileContentUtil) {
-    this.fileContentUtil = fileContentUtil;
-  }
-
-  @Override
-  public String apply(FileResource rsrc)
-      throws ResourceNotFoundException, IOException {
-    String path = rsrc.getPatchKey().get();
-    if (Patch.COMMIT_MSG.equals(path)) {
-      return FileContentUtil.TEXT_X_GERRIT_COMMIT_MESSAGE;
-    }
-    return fileContentUtil.getContentType(
-        rsrc.getRevision().getControl().getProjectControl().getProjectState(),
-        ObjectId.fromString(rsrc.getRevision().getPatchSet().getRevision().get()),
-        path);
-  }
-}

gerrit-server/src/main/java/com/google/gerrit/server/change/Module.java

@@ -103,7 +103,6 @@ public class Module extends RestApiModule {
     put(FILE_KIND, "reviewed").to(PutReviewed.class);
     delete(FILE_KIND, "reviewed").to(DeleteReviewed.class);
     get(FILE_KIND, "content").to(GetContent.class);
-    get(FILE_KIND, "type").to(GetContentType.class);
     get(FILE_KIND, "diff").to(GetDiff.class);
 
     child(CHANGE_KIND, "edit").to(ChangeEdits.class);
@@ -115,7 +114,6 @@ public class Module extends RestApiModule {
     put(CHANGE_EDIT_KIND, "/").to(ChangeEdits.Put.class);
     delete(CHANGE_EDIT_KIND).to(ChangeEdits.DeleteContent.class);
     get(CHANGE_EDIT_KIND, "/").to(ChangeEdits.Get.class);
-    get(CHANGE_EDIT_KIND, "type").to(ChangeEdits.GetType.class);
 
     install(new FactoryModule() {
       @Override