Rename repo name to pingcap/tiflow

[amyangfei]

We are going to rename pingcap/ticdc to pingcap/tiflow

Motivation

This repo maintains both TiCDC and DM, the repo name doesn't match the product exactly. We are planning to use a more accurate repo name to make it self-explanatory.

Procedure

Filing an issue to sort through what needs to be done:

• 1. Announce to TiDB/TiKV communities via https://internals.tidb.io/. (prepare on 2021/12/11-2021/12/12, 2021/12/18-2021/12/19) https://internals.tidb.io/t/topic/512
• 2. Pause CI, prepare a PR to replace import path.
• 3. Rename the repo from pingcap/ticdc to pingcap/tiflow.
• 4. Reconfigure CI, GitHub bot and automated testing.
• 5. Prepare and merge PR that changes import path in master branch.
• 6. Cherry pick import patch PR to release branches.
• 7. Reconfigure CI, GitHub bot and automated testing for release branches.
• 8. Check whether we need to update related documents.
• 9. Refine README.md in root directory.
• 10. Update dependency in other repos, such as https://github.com/pingcap/tidb-tools

Some related issues

• Does release branche need cherry-pick
  Yes, since we will change the repo name and go version mechanism, we need to cherry the path change to release branches.

• Are released TiCDC urls and go mod versions still available
  Yes. GitHub will redirect all requests to the new URL and go mod download still works. All old versions can be built as before.

• Is there any change to feature release?
  No, we still release TiCDC and DM as before, there is no any change to release binary and product usage, they are independent binaries and follow the same release procedure as TiDB.

[amyangfei]

Some remaining problems

• Github action for Arm64 build is failed.
• some pingcap/ticdc in files of dir .gitHub are still remained. github: replace pingcap/ticdc with pingcap/tiflow in workflow #3965
• coveralls.io seems not work as expected after rename. https://coveralls.io/github/pingcap/tiflow

[Rustin170506]

Some remaining problems

* [ ]  Github action for Arm64 build is failed.

It may have nothing to do with it, it may simply be that the arm machine went offline. I'll confirm it next Monday. Because it looks like the x86 machine is still online.

[lance6716]

I did these steps to my existing PR

sed -i "s/github.com\/pingcap\/ticdc/github.com\/pingcap\/tiflow/g" $(find . -type f|grep -vE "bin/|.git")
sed -i "s/pingcap\/ticdc/pingcap\/tiflow/g" $(find . -type f|grep -vE "bin/|.git")
make fmt

then git pull upstream master, still found conflicts

git status to see conflicting files, use git rm <file...> to resolve "Deleted by them" files, and use git checkout . --theirs to accept master changes

[amyangfei]

I did these steps to my existing PR

sed -i "s/github.com\/pingcap\/ticdc/github.com\/pingcap\/tiflow/g" $(find . -type f|grep -vE "bin/|.git")
sed -i "s/pingcap\/ticdc/pingcap\/tiflow/g" $(find . -type f|grep -vE "bin/|.git")
make fmt

then git pull upstream master, still found conflicts

git status to see conflicting files, use git rm <file...> to resolve "Deleted by them" files, and use git checkout . --theirs to accept master changes

The script is almost ok, except for two changes

sed -i "s/PROJECT=ticdc/PROJECT=tiflow/g" Makefile
sed -i "s/pingcap\/ticdc/pingcap\/tiflow/g" $(find .github -type f) ref: https://github.com/pingcap/tiflow/pull/3965, still have not been merged

maybe it is more convenient to check out latest master(or release branch) and pick the changing commits. @lance6716

[amyangfei]

Most of the work has been done, except for the update of readme. Close it now.