Add featured images for blog articles (#7)

Author: jnonino

content/blog/continuous-delivery/featured.en.png

@@ -1,20 +1,162 @@
 ---
-title: "Revert a pushed change in Git"
+title: "Reverting changes in Git"
 authors:
   - jnonino
 description: >
-  Have you ever pushed a change in Git and it was wrong? Here you'll learn how to revert the change, even if the problem was with a merge commit.
+  This article will teach you how to discard commits in Git before pushing them and, how to revert a change that you have already pushed.
 date: 2023-01-18
 tags: ["Version Control", "VCS", "Git", "Revert"]
 ---
 
+## Reverting a commit before pushing
+
+When we have created a commit locally but have not published it to the remote yet, we can use `git reset` to undo the commit and, if we wish, discard the changes.
+Although there are several options for `git reset` the most used are:
+
+> - `--soft`: Does not touch the index file or the working tree at all (but resets the head to <COMMIT>, just like all modes do). This leaves all your changed files "Changes to be committed", as git status would put it.
+> - `--hard`: Resets the index and working tree. Any changes to tracked files in the working tree since <COMMIT> are discarded. Any untracked files or directories in the way of writing any tracked files are simply deleted.
+>
+> [Git reset documentation](https://git-scm.com/docs/git-reset)
+> {: style="text-align: right;"}
+
+Here there is an example about using `git reset`. We start by changing a file and creating a commit with the change.
+
+```bash
+bash-3.2$  cat README.md
+# Index
+
+1
+bash-3.2$
+bash-3.2$  cat README.md
+# Index
+
+1
+2
+bash-3.2$
+bash-3.2$  git add README.md
+bash-3.2$
+bash-3.2$  git commit -m "Add number 2 in README.md"
+[main 3734fd5] Add number 2 in README.md
+ 1 file changed, 1 insertion(+)
+```
+
+`git status` shows there is one commit pending to be published.
+
+```bash
+bash-3.2$  git status
+On branch main
+Your branch is ahead of 'origin/main' by 1 commit.
+  (use "git push" to publish your local commits)
+
+nothing to commit, working tree clean
+```
+
+Using `git reflog` to see the history.
+
+```bash
+3734fd5 (HEAD -> main) HEAD@{0}: commit: Add number 2 in README.md
+866bfa8 (origin/main) HEAD@{1}: revert: Revert "Merge branch 'feature-1'"
+e2f6d08 HEAD@{2}: merge feature-1: Merge made by the 'ort' strategy.
+23644da HEAD@{3}: checkout: moving from feature-1 to main
+```
+
+Now we can use `git reset --soft <COMMIT_ID>` to undo the commit but keep the changes.
+
+```bash
+bash-3.2$  git reset --soft 866bfa8
+bash-3.2$
+bash-3.2$  git status
+On branch main
+Your branch is up to date with 'origin/main'.
+
+Changes to be committed:
+  (use "git restore --staged <file>..." to unstage)
+        modified:   README.md
+```
+
+`git log` after using `git reset`
+
+```bash
+commit 866bfa8a952d11240707ebfc87f3266034d42443 (HEAD -> main, origin/main)
+Author: Julian Nonino <learn.software.eng+jnonino@gmail.com>
+Date:   Wed Jan 18 20:06:40 2023 -0300
+
+    Revert "Merge branch 'feature-1'"
+
+    This reverts commit e2f6d08d3b38a02a1c026cfb879f3131536757ac, reversing
+    changes made to 23644dab9fc5828ecdd358c6d3acb4196ed23546.
+```
+
+We create a new commit so we can test the `git reset --hard` command.
+
+```bash
+bash-3.2$  git status
+On branch main
+Your branch is up to date with 'origin/main'.
+
+Changes to be committed:
+  (use "git restore --staged <file>..." to unstage)
+        modified:   README.md
+
+bash-3.2$  git commit -m "Add number 2 in README.md - NEW COMMIT"
+[main 2e7193d] Add number 2 in README.md - NEW COMMIT
+ 1 file changed, 1 insertion(+)
+```
+
+`git log` now shows the new commit.
+
+```bash
+commit 2e7193db650b9ba0762fe73525df599a08f8577d (HEAD -> main)
+Author: Julian Nonino <learn.software.eng+jnonino@gmail.com>
+Date:   Thu Jan 19 08:32:57 2023 -0300
+
+    Add number 2 in README.md - NEW COMMIT
+
+commit 866bfa8a952d11240707ebfc87f3266034d42443 (origin/main)
+Author: Julian Nonino <learn.software.eng+jnonino@gmail.com>
+Date:   Wed Jan 18 20:06:40 2023 -0300
+
+    Revert "Merge branch 'feature-1'"
+
+    This reverts commit e2f6d08d3b38a02a1c026cfb879f3131536757ac, reversing
+    changes made to 23644dab9fc5828ecdd358c6d3acb4196ed23546.
+```
+
+Now we can use `git reset --hard <COMMIT_ID>` to undo the commit and discard all the changes.
+
+```bash
+bash-3.2$  git reset --hard 866bfa8
+HEAD is now at 866bfa8 Revert "Merge branch 'feature-1'"
+bash-3.2$
+bash-3.2$  git status
+On branch main
+Your branch is up to date with 'origin/main'.
+
+nothing to commit, working tree clean
+```
+
+`git log` remains as it nothing had happened.
+
+```bash
+commit 866bfa8a952d11240707ebfc87f3266034d42443 (HEAD -> main, origin/main)
+Author: Julian Nonino <learn.software.eng+jnonino@gmail.com>
+Date:   Wed Jan 18 20:06:40 2023 -0300
+
+    Revert "Merge branch 'feature-1'"
+
+    This reverts commit e2f6d08d3b38a02a1c026cfb879f3131536757ac, reversing
+    changes made to 23644dab9fc5828ecdd358c6d3acb4196ed23546.
+```
+
+## Reverting a commit after it was pushed
+
 When we realized that the last commit was a mistake but we already published it, the command to use is `git revert <COMMIT_HASH>`.
 
 - First we need to locate the ID of the commit we want to revert, it can be done with `git log` or `git reflog` commands.
 - Then, run the `git revert <COMMIT_HASH>` command using the ID obtained in the previous step. Use the options `-e` or `--edit` to edit the commit message if we like.
 - Push our changes so the revert is available for everyone in our group.
 
-## Reverting multiple commits
+### Reverting multiple commits
 
 If we need to revert multiple commits we can revert them one by one using the `--no-commit` option in order to create a single revert commit at the end.
 
@@ -34,7 +176,7 @@ bash-3.2$  git commit -m "Revert to version in COMMIT-3"
 bash-3.2$  git push
 ```
 
-## Reverting a merge commit
+### Reverting a merge commit
 
 >  -m parent-number, --mainline parent-number
 >