Sparse checkout example

This repository is an artificial example for a large mono repository. The mono repository has two components A and B. A has lots of large files/binary content and B has only source code. Teams that are only working on component B usually don't want to download all the data.

Therefore, this repository introduces a bootstrap branch with just a run script. The bootstrap branch can be cloned quickly and the run script initializes the tree for the respective teams using Git sparse checkout. This way only the necessary amount of data is transferred. In addition, the run script configures the local Git installation in an optimal way and ensures a recent Git version.

Usage

In order to make use of the run script, clone the repository with only the bootstrap branch:

$ git clone --filter=blob:none -b bootstrap git@github.com:larsxschneider/sparse-checkout-example.git

Afterwards invoke the run script:

$ ./sparse-checkout-example/run

Examples

Example 1: Normal clone

A normal clone of the repository transfers ~50 MB of data and takes ~15 seconds with the given network connection:

$ time git clone git@github.com:larsxschneider/sparse-checkout-example.git

Cloning into 'sparse-checkout-example'...
remote: Enumerating objects: 21, done.
remote: Counting objects: 100% (21/21), done.
remote: Compressing objects: 100% (12/12), done.
remote: Total 21 (delta 2), reused 17 (delta 1), pack-reused 0
Receiving objects: 100% (21/21), 47.70 MiB | 3.42 MiB/s, done.
Resolving deltas: 100% (2/2), done.
git clone git@github.com:larsxschneider/sparse-checkout-example.git  0.24s user 0.29s system 3% cpu 14.772 total

Example 2: Filter clone with bootstrap script:

A clone of the bootstrap branch without blobs transfers ~0.003 MB of data and takes ~2 seconds with the given network connection:

$ time git clone --filter=blob:none -b bootstrap git@github.com:larsxschneider/sparse-checkout-example.git

Cloning into 'sparse-checkout-example'...
remote: Enumerating objects: 12, done.
remote: Counting objects: 100% (12/12), done.
remote: Compressing objects: 100% (9/9), done.
Receiving objects: 100% (12/12), done.
Resolving deltas: 100% (2/2), done.
remote: Total 12 (delta 2), reused 10 (delta 1), pack-reused 0
remote: Enumerating objects: 1, done.
remote: Counting objects: 100% (1/1), done.
remote: Total 1 (delta 0), reused 1 (delta 0), pack-reused 0
Receiving objects: 100% (1/1), 2.47 KiB | 2.47 MiB/s, done.
git clone --filter=blob:none -b bootstrap   0.02s user 0.08s system 7% cpu 1.360 total

Afterwards we could checkout just the smallish component B which would only take 6 more seconds:

./sparse-checkout-example/run

##############################################################
     Checking Git and Git LFS...
##############################################################
Git version:     2.34.1
Git LFS version: 2.13.3

Git user:  John Doe
Git email: jdoe@github.com

##############################################################
     Bootstrapping repository...
##############################################################

##############################################################
     What components of the repository do you want?
##############################################################
1: ALL
2: Component A
3: Component B

?: 3
remote: Enumerating objects: 5, done.
remote: Counting objects: 100% (5/5), done.
remote: Total 5 (delta 0), reused 3 (delta 0), pack-reused 0
Receiving objects: 100% (5/5), 745 bytes | 745.00 KiB/s, done.

##############################################################
     Hurray! Your Git repository is ready for you!
##############################################################
Bootstrap time: 6 s

If we checkout the bigger component A then more data is transferred and it takes longer (10 seconds):

./sparse-checkout-example/run

##############################################################
     Checking Git and Git LFS...
##############################################################
Git version:     2.34.1
Git LFS version: 2.13.3

Git user:  John Doe
Git email: jdoe@github.com

##############################################################
     Bootstrapping repository...
##############################################################

##############################################################
     What components of the repository do you want?
##############################################################
1: ALL
2: Component A
3: Component B

?: 2
remote: Enumerating objects: 3, done.
remote: Counting objects: 100% (3/3), done.
remote: Total 3 (delta 0), reused 3 (delta 0), pack-reused 0
Receiving objects: 100% (3/3), 47.70 MiB | 8.63 MiB/s, done.

##############################################################
     Hurray! Your Git repository is ready for you!
##############################################################
Bootstrap time: 10 s