Change variable based on current stage - node.js

I have Serverless application that has two stages: develop (on branch develop) and master (on branch master).
It has a file called config.js like this:
API_URL: api.prod.some-server.com
But I want that "prod" changed to "dev" when I'm on develop branch / on develop stage environment.
It's kinda exhausting if I should change the API_URL back-and-forth (prod -> dev) when I changed the current branch/dev_stage.
Is there any possible to automate this?
Thank you

Is there any possible to automate this?
Yes: You would need to not version config.js (keep it private), but to generate it (with the right value in it).
The generation script will determine the name of the checked out branch with:
branch=$(git rev-parse --symbolic --abbrev-ref HEAD)
Or (since Git 2.22, Q2 2019)
branch=$(git branch --show-current)
That means you could:
version only a template file config.js.tpl
version value files named after the branches: config.js.dev, config.js.master: since they are different, there is no merge issue when merging or switching branches.
Finally, you would register (in a .gitattributes declaration) a content filter driver.
(image from "Customizing Git - Git Attributes", from "Pro Git book")
The smudge script, associated to the template file (config.js.tpl), would generate (automatically, on git checkout) the actual config.js file by looking values in the right config.js.<branch> value file.
The generated actual config.js file remains ignored (by the .gitignore).
See a complete example at "git smudge/clean filter between branches".

Related

How to commit into a branch in git and show result into a git graph? [duplicate]

Using gitk log, I could not spot a difference between the effect of git merge and git merge --no-ff. How can I observe the difference (with a git command or some tool)?
The --no-ff flag prevents git merge from executing a "fast-forward" if it detects that your current HEAD is an ancestor of the commit you're trying to merge. A fast-forward is when, instead of constructing a merge commit, git just moves your branch pointer to point at the incoming commit. This commonly occurs when doing a git pull without any local changes.
However, occasionally you want to prevent this behavior from happening, typically because you want to maintain a specific branch topology (e.g. you're merging in a topic branch and you want to ensure it looks that way when reading history). In order to do that, you can pass the --no-ff flag and git merge will always construct a merge instead of fast-forwarding.
Similarly, if you want to execute a git pull or use git merge in order to explicitly fast-forward, and you want to bail out if it can't fast-forward, then you can use the --ff-only flag. This way you can regularly do something like git pull --ff-only without thinking, and then if it errors out you can go back and decide if you want to merge or rebase.
Graphic answer to this question
Here is a site with a clear explanation and graphical illustration of using git merge --no-ff:
Until I saw this, I was completely lost with git. Using --no-ff allows someone reviewing history to clearly see the branch you checked out to work on. (that link points to github's "network" visualization tool) And here is another great reference with illustrations. This reference complements the first one nicely with more of a focus on those less acquainted with git.
Basic info for newbs like me
If you are like me, and not a Git-guru, my answer here describes handling the deletion of files from git's tracking without deleting them from the local filesystem, which seems poorly documented but often occurrence. Another newb situation is getting current code, which still manages to elude me.
Example Workflow
I updated a package to my website and had to go back to my notes to see my workflow; I thought it useful to add an example to this answer.
My workflow of git commands:
git checkout -b contact-form
(do your work on "contact-form")
git status
git commit -am "updated form in contact module"
git checkout master
git merge --no-ff contact-form
git branch -d contact-form
git push origin master
Below: actual usage, including explanations.
Note: the output below is snipped; git is quite verbose.
$ git status
# On branch master
# Changed but not updated:
# (use "git add/rm <file>..." to update what will be committed)
# (use "git checkout -- <file>..." to discard changes in working directory)
#
# modified: ecc/Desktop.php
# modified: ecc/Mobile.php
# deleted: ecc/ecc-config.php
# modified: ecc/readme.txt
# modified: ecc/test.php
# deleted: passthru-adapter.igs
# deleted: shop/mickey/index.php
#
# Untracked files:
# (use "git add <file>..." to include in what will be committed)
#
# ecc/upgrade.php
# ecc/webgility-config.php
# ecc/webgility-config.php.bak
# ecc/webgility-magento.php
Notice 3 things from above:
1) In the output you can see the changes from the ECC package's upgrade, including the addition of new files.
2) Also notice there are two files (not in the /ecc folder) I deleted independent of this change. Instead of confusing those file deletions with ecc, I'll make a different cleanup branch later to reflect those files' deletion.
3) I didn't follow my workflow! I forgot about git while I was trying to get ecc working again.
Below: rather than do the all-inclusive git commit -am "updated ecc package" I normally would, I only wanted to add the files in the /ecc folder. Those deleted files weren't specifically part of my git add, but because they already were tracked in git, I need to remove them from this branch's commit:
$ git checkout -b ecc
$ git add ecc/*
$ git reset HEAD passthru-adapter.igs
$ git reset HEAD shop/mickey/index.php
Unstaged changes after reset:
M passthru-adapter.igs
M shop/mickey/index.php
$ git commit -m "Webgility ecc desktop connector files; integrates with Quickbooks"
$ git checkout master
D passthru-adapter.igs
D shop/mickey/index.php
Switched to branch 'master'
$ git merge --no-ff ecc
$ git branch -d ecc
Deleted branch ecc (was 98269a2).
$ git push origin master
Counting objects: 22, done.
Delta compression using up to 4 threads.
Compressing objects: 100% (14/14), done.
Writing objects: 100% (14/14), 59.00 KiB, done.
Total 14 (delta 10), reused 0 (delta 0)
To git#github.com:me/mywebsite.git
8a0d9ec..333eff5 master -> master
Script for automating the above
Having used this process 10+ times in a day, I have taken to writing batch scripts to execute the commands, so I made an almost-proper git_update.sh <branch> <"commit message"> script for doing the above steps. Here is the Gist source for that script.
Instead of git commit -am I am selecting files from the "modified" list produced via git status and then pasting those in this script. This came about because I made dozens of edits but wanted varied branch names to help group the changes.
Merge Strategies
Explicit Merge (aka non fast-forward): Creates a new merge commit. (This is what you will get if you used --no-ff.)
Fast Forward Merge: Forward rapidly, without creating a new commit:
Rebase: Establish a new base level:
Squash: Crush or squeeze (something) with force so that it becomes flat:
The --no-ff option ensures that a fast forward merge will not happen, and that a new commit object will always be created. This can be desirable if you want git to maintain a history of feature branches.
In the above image, the left side is an example of the git history after using git merge --no-ff and the right side is an example of using git merge where an ff merge was possible.
EDIT: A previous version of this image indicated only a single parent for the merge commit. Merge commits have multiple parent commits which git uses to maintain a history of the "feature branch" and of the original branch. The multiple parent links are highlighted in green.
This is an old question, and this is somewhat subtly mentioned in the other posts, but the explanation that made this click for me is that non fast forward merges will require a separate commit.
The --no-ff flag causes the merge to always create a new commit object, even if the merge could be performed with a fast-forward. This avoids losing information about the historical existence of a feature branch and groups together all commits that together added the feature
Other answers indicate perfectly well that --no-ff results in a merge commit. This retains historical information about the feature branch which is useful since feature branches are regularly cleaned up and deleted.
This answer may provide context for when to use or not to use --no-ff.
Merging from feature into the main branch: use --no-ff
Worked example:
$ git checkout -b NewFeature
[work...work...work]
$ git commit -am "New feature complete!"
$ git checkout main
$ git merge --no-ff NewFeature
$ git push origin main
$ git branch -d NewFeature
Merging changes from main into feature branch: leave off --no-ff
Worked example:
$ git checkout -b NewFeature
[work...work...work]
[New changes made for HotFix in the main branch! Lets get them...]
$ git commit -am "New feature in progress"
$ git pull origin main
[shortcut for "git fetch origin main", "git merge origin main"]
What’s a fast-forward?
A fast-forward is what Git does when you merge or rebase against a branch simply ahead of the one you have checked-out.
Given the following branch setup:
You’ve got both branches referencing the same commit. They’ve both got precisely the same history. Now commit something to feature.
The master branch is still referencing 7ddac6c, while the feature has advanced by two commits. The feature branch can now be considered ahead of the master.
It’s now relatively easy to see what’ll happen when Git does a fast-forward. It simply updates the master branch to reference the exact commit that feature does. No changes are made to the repository itself, as the commits from the feature already contain all the necessary changes.
Your repository history would now look like this:
When doesn’t a fast-forward happen?
Fast-forwards don’t happen when changes have been made in the original branch and the new branch.
If you were to merge or rebase the feature onto master, Git would be unable to do a fast-forward because the trees have both diverged. Considering Git commits are immutable, there’s no way for Git to get the commits from feature into master without changing their parent references.

How to pull from specific branch in git- understanding gap

I am using gitlab and really confused in few things. :
When we create new branch by git checkout -b test. Does it create copy of master or it creates copy of branch i am currently in?
For example: I am currently at branch dev, then i write command git checkout -b test. So it will be copy of dev, not masters?
Pull : when we write git pull , it pulls changes of current branch from remote branch of same name. Its used when more people are working on same project.
Example : I am at branch dev, i write git pull, it updates my local as of dev in remote. Now i created a new branch test, checkout test branch and do git pull. It gives me :There is no tracking information for the current branch.
Please specify which branch you want to rebase against.
its because there is no test branch in remote ?
What command to be used if i want to pull from dev branch while my current branch is test? is it git pull --rebase dev test?
When we write git push, it pushes current branch to remote one.
example : i am on branch test, i add, commit and write git push. It simply pushes my branch test to remote with same name as test.
Can we push to specific branch like push test to dev?
What is difference in following considering i am at branch test:
git push
git push origin test
they both push to remote?
My requirement is : there is branch dev which is not master branch, i am supposed to work on this branch as starting and end point. Like, new branch should be copy of this and i am supposed to push to same branch.
Does it create copy of master or it creates copy of branch i am currently in?
It creates a new branch named test based on the current branch, whatever that might be, as a starting point.
What command to be used if i want to pull from dev branch while my current branch is test?
I believe you can pull any branch you wish into your current branch. E.g. if you were on branch test and wanted to pull dev you could just use:
git pull origin dev
Can we push to specific branch like push test to dev?
Yes, can specify both the local and remote branch names when pushing, e.g.
git push origin test:dev
1- When you do git checkout -b test it creates copy of your current branch(in this case 'dev').
2- git pull will only sync your changes between remote and local. If you upload the branch and try to pull, it does not work because your local and remote changes will be synchronized.
3- This could help you : Make an existing Git branch track a remote branch?.
If you want to work in a copy of a branch, you should do this:
git checkout <origin_branch> (master, dev, what u want )
git checkout -b <work_branch> (test, for example. This create a copy of your origin branch)
After this, you have a new branch 'test' in your local repository. If you want to push this branch on the repo:
git add .
git commit -m "Pushing new branch test"
git --set-upstream origin <your_new_branch>

Branch-specific configuration file maintenance with git

Here is a question keeps me puzzled for a long time as I cannot find nice and more-or-less universal solution to it.
Lets say there are two git branches available, production and dev; each uses it's own configurable parameters for some tasks (i.e. credentials, build path, test/deployment scripts switches et cetera). Same time implementation scripts & code is common for both branches.
Now, the problem arises is - how to maintain branch-specific configuration within git repository the way required. One of common solutions out there is to use 'template' configuration file within git, symlinking and ignoring the concrete for specific branch, like
$ cat .gitignore | grep conf
/concrete.conf
$ ls -l *.conf
lrwxrwxrwx 1 1000 100 12 Oct 29 10:23 concrete.conf -> generic.conf
-rw-r--r-- 1 1000 100 0 Oct 29 10:16 generic.conf
breaking and adjusting concrete.conf on development box next. Yet not a solution I'm in pursuit for.
My requirements (ok, wishes) are:
support separate configuration file per git branch, and
keep branch-specific configuration file managed by git same time
Is it even possible? Could be (actually, preferred to be file sourced by some other one, but it's none related...)
The best that has came to my mind so far is to use post-merge hooks to adjust per-branch configuration per se from some other source ignored by git, but it stinks from the very beginning.
Any suggestions on solution of problem described ?
PS: *nix-specific suggestions (i.e. using symlinks/hardlinks) suggestions is absolutely fine, I do do have any interest in M$ targets
It is possible, and does not involve symlinking.
You do not version my.config, but a template file my.config.tpl, and a value file (with values for each branches)
prod.conf
dev.conf
Then, you can use a content filter driver, using .gitattributes declaration.
(image from "Customizing Git - Git Attributes", from "Pro Git book")
The script generate my.config file by replacing placeholder values with the values of the <branch.conf> file, each time you checkout a branch.
You can know about the current branch name with:
branch=$(git rev-parse --symbolic --abbrev-ref HEAD)
The generated actual my.config remains ignored (by the .gitignore).
That means your actual working tree does not get "dirty".
The smudge script selects the correct value file and generates the correct web.config based on the template the smudge script is applied on during a git checkout.
See a complete example at "git smudge/clean filter between branches".

How to create a GitLab merge request via command line

We are working on integrating GitLab (enterprise edition) in our tooling, but one thing that is still on our wishlist is to create a merge request in GitLab via a command line (or batchfile or similar, for that matter). We would like to integrate this in our tooling. Searching here and on the web lead me to believe that this is not possible with native GitLab, but that we need additional tooling for that.
Am I correct? And what kind of tooling would I want to use for this?
As of GitLab 11.10, if you're using git 2.10 or newer, you can automatically create a merge request from the command line like this:
git push -o merge_request.create
More information can be found in the docs.
It's not natively supported, but it's not hard to throw together. The gitlab API has support for opening MR: https://github.com/gitlabhq/gitlabhq/blob/master/doc/api/merge_requests.md#create-mr
You can use following utility.
Disclosure : I developed it.
https://github.com/vishwanatharondekar/gitlab-cli
You can create merge request using this.
Some of the features it has are.
Base branch is optional. If base branch is not provided. Current branch is used as base branch.
target branch is optional. If target branch is not provided, default branch of the repo in gitlab will be used.
Created pull request page will be opened automatically after successful creation.
If title is not supported with -m option value. It will be taken from in place editor opened. First line is taken as title.
In the editor opened third line onwards takes as description.
Comma separated list of labels can be provided with its option.
Supports CI.
Repository specific configs can be given.
squash option is available.
remove source branch option is available.
If you push your branch before this command (git push -o merge_request.create) it will not work. Git will response with Everything up-to-date and merge request will not be created (gitlab 12.3).
When I tried to remove my branch from a server (do not remove your local branch!!!) then it worked for me in this form.
git push --set-upstream origin your-branch-name -o merge_request.create
In addition to answering of #AhmadSherif, You can use merge_request.target=<branch_name> for declaring the target branch.
sample usage:
git push -o merge_request.create -o merge_request.target=develop origin feature
Simple This:
According to the Gitlab documents, you can define an alias for this command to simpler usage.
git config --global alias.mwps "push -o merge_request.create -o
merge_request.target=master -o merge_request.merge_when_pipeline_succeeds"
I made a shell function which opens up the GitLab MR web page with desired parameters.
Based on the directory with the git repo you are currently in, it:
Finds the correct URL to your repo.
Sets the source branch to the branch you're currently on.
As a optional first argument you can provide the target branch. Otherwise, GitLab defaults to your default branch, which is typically master.
gmr() {
# A quick way to open a GitLab merge request URL for the current git branch
# you're on. The optional first argument is the target branch.
repo_path=$(git remote get-url origin --push | sed 's/^.*://g' | sed 's/.git$//g')
current_branch=$(git rev-parse --abbrev-ref HEAD)
if [[ -n $1 ]]; then
target_branch="&merge_request[target_branch]=$1"
else
target_branch=""
fi
xdg-open "https://gitlab.com/$repo_path/merge_requests/new?merge_request[source_branch]=$current_branch$target_branch"
}
You can set more default values in the URL, like removing the source branch after merge:
&merge_request[force_remove_source_branch]=true
Or assignee to someone:
&merge_request[assignee_ids][]=12345
Or add a reviewer:
&merge_request[reviewer_ids][]=54321
You can easily find the possible query string parameters by searching the source of the GitLab MR webpage for merge_request[.
As of now, GitLab sadly does not support this, however I recently saw it on their issue tracker. It appears one can expect a 'native tool' in the upcoming months.
GitLab tweeted out about numa08/git-gitlab some time ago, so I guess this would be worth a try.
In our build script we just pop up the browser with the correct URL and let the developer write his comments in the form hit save to create the merge request. You get this url with the correct parameters by creating a merge request manually and copying the url of the form.
#!/bin/bash
set -e
set -o pipefail
BRANCH=${2}
....
git push -f origin-gitlab $BRANCH
open "https://gitlab.com/**username**/**project-name**/merge_requests/new?merge_request%5Bsource_branch%5D=$BRANCH&merge_request%5Bsource_project_id%5D=99999&merge_request%5Btarget_branch%5D=master&merge_request%5Btarget_project_id%5D=99999"
You can write a local git alias to open a Gitlab Merge Request creation page in the default browser for the currently checked-out branch.
[alias]
lab = "!start https://gitlab.com/path/to/repo/-/merge_requests/new?merge_request%5Bsource_branch%5D=\"$(git rev-parse --abbrev-ref HEAD)\""
(this is a very simple alias for windows; I guess there are equivalent replacements for "start" on linux and fancier aliases that work with github and bitbucket too)
As well as being able to immediately see&modify the details of the MR, the advantage of this over using the merge_request.create push option is that you don't need your local branch to be behind the remote for it to work.
You might additionally want to store the alias in the repo itself.
I use https://github.com/mdsb100/cli-gitlab
I am creating the MR from inside of a gitlab CI docker container based on alpine linux, so I include the install command in before-script (that could also be included in your image). All commands in the following .gitlab-ci.yml file, are also relevant for normal command line usage (as long as you have the cli-gitlab npm installed).
variables:
TARGET_BRANCH: 'live'
GITLAB_URL: 'https://your.gitlab.net'
GITLAB_TOKEN: $PRIVATE_TOKEN #created in user profile & added in project settings
before-script:
-apk update && apk add nodejs && npm install cli-gitlab -g
script:
- gitlab url $GITLAB_URL && gitlab token $GITLAB_TOKEN
- 'echo "gitlab addMergeRequest $CI_PROJECT_ID $CI_COMMIT_REF_NAME \"$TARGET_BRANCH\" 13 `date +%Y%m%d%H%M%S`"'
- 'gitlab addMergeRequest $CI_PROJECT_ID $CI_COMMIT_REF_NAME "$TARGET_BRANCH" 13 `date +%Y%m%d%H%M%S` 2> ./mr.json'
- cat ./mr.json
This will echo true if the merge request already exists, and echo the json result of the new MR if it succeeds to create one (also saving to a mr.json file).
Since GitLab 15.7 (Dec. 2022), the GitLab CLI glab is officially integrated to GitLab.
Introducing the GitLab CLI
The command line is one of the most important tools in a software engineer’s toolkit and the majority of their process and work revolve around tools available there. They customize their CLI with styles and extend it through applications to ensure maximum efficiency while performing tasks. The CLI is the backbone of scripts and workflows developers depend on to complete their work.
To support more developers where they’re already working, we’ve adopted the open source project glab, which will form the foundation of GitLab’s native CLI experience.
The GitLab CLI brings GitLab together with Git and your code, with no application or tab switching required.
You can read about our adoption of glab, our partnership with 1Password, and how to contribute to the project in our blog post.
A special thank you to Clement Sam for creating glab and trusting us with its future.
That means you can create a MR with glab mr create:
glab mr create -a username -t "fix annoying bug"

how to change branch on --bare remote from local in git

I am trying to make a hook on a remote --bare repository that will copy the source code I send from a local git, in different folders according the branch I'm sending to. I have 3 branches on local: master, development and release so I wish that on the remote would be 3 folders containing the source code of each branch. I found that using:
git rev-parse --abbrev-ref HEAD
in combination with a series of if conditions could do the trick. The only problem is that the HEAD remains the same on remote for whatever branch you send to. Is there any code that could be used in the hook, so it would know that I am sending to a certain branch? Or is there any other method for doing this? Thanks!
Your one bare repo will have all 3 branches on it. You can use git modifiers like this to make 3 separate directories update to what each branch contains:
git --work-tree=/some/project/dir/branch1 --git-dir=/path/to/bare/repo checkout branch1 -- .
To avoid specifying those options, you can set their corresponding environment variables:
GIT_WORK_TREE
GIT_DIR
This way you can keep one bare repo and 3 separate directories that update when branches are pushed. Remember what the arguments are that are provided in your hook. The first is the branch name.

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