1 unstable release

0.1.1	Jun 9, 2024
0.1.0	~~Jun 8, 2024~~

#14 in #load-balancer

Apache-2.0

2.5MB
501 lines

Carapace LB - A Path Based Load Balancer

Carapace LB is a path-based load balancer that leverages the Pingora Framework by Cloudflare to manage and route traffic efficiently.

NOTE: I havent included SNI here because I dont have yet a good understanding on how to apply SNI in pingora.

Configuration

Since the application uses Pingora, it also inherit its configurations. To know more about Pingora related configuration, please refer here: https://github.com/cloudflare/pingora/blob/main/docs/user_guide/conf.md

The configuration uses the TOML format. For more details, refer to the TOML documentation.

High Level Diagram

Diagram

`[load_balancer]`

Configure the load balancer.

Property	Description
`host`	The address of the load balancer.
`port`	The port on which the load balancer will listen.
`routes_path`	The file where routes will be saved during service discovery updates.
`enable_tls_ssl`	Set to `true` to enable TLS/SSL. Set to `false` to disable TLS/SSL.
`ca_crt_path`	The certficate path for the .crt file.
`ca_pem_path`	The certficate path for the .pem file.
`allow_file_types_pattern`	The regular expression pattern for matching files in the url path.
`debug`	Set to empty string `""`. If set to `"INFO"` it will only print minimal info. such as Upstream Address and the URL Path. If set to `"DEBUG"` it will only print minimal info. such as Upstream Address and all the request information.

Example

[load_balancer]
host="0.0.0.0"
port=6170
routes_path="routes.json"
enable_tls_ssl=true
ca_crt_path="certs/localhost.crt"
ca_pem_path="certs/localhost.pem"
allow_file_types_pattern="[0-9|_|-|A-Z|a-z]*\\.(js|css|png|jpeg|jpg|ico)"
debug="INFO"

`[[proxy_services]]`

When enabling use_container please make sure that the load balancer has local access to the docker daemon and to the network of the containers.

Configure the proxy services for container discovery based on container labels.

Property	Description
`container_label_key`	The key of the container label (used if `use_container` is set to `true`).
`container_label_value`	The value of the container label (used if `use_container` is set to `true`).
`path`	The URL path to match. If the URL path matches, traffic is routed to this proxy service.
`port`	The port on which the proxy service listens.
`use_container`	Set to `true` if upstreams are containers. The load balancer should be containerized and in the same network as the containers. Set to `false` when targeting specific addresses.
`host`	The specific addresses to load balance. Useful if applications are on separate machines.

Example

[[proxy_services]]
container_label_key="cbl.dev.nginx"
container_label_value="groupA"
path = "/"
port = 3101
use_container=false
host = "0.0.0.0"

[[proxy_services]]
container_label_key="cbl.dev.nginx"
container_label_value="groupC"
path="/"
use_container=false
port = 3102
host = "0.0.0.0"

`[health_check]`

Configure health checks and service discovery.

For more details, refer to the Pingora LoadBalancer documentation.

Property	Description
`health_check_frequency`	The interval (in milliseconds) at which health checks are performed.
`update_frequency`	The interval (in milliseconds) at which service discovery is performed.
`parallel_health_check`	Set to `false` to perform health checks sequentially.

Example

[health_check]
health_check_frequency=1000
update_frequency=1500
parallel_health_check=false

Build

cargo build

Build Specific Platform

cargo build --target=x86_64-unknown-linux-gnu

See rustup target list for the list of platforms.

Test

cargo test -- --nocapture

Run

cargo run

Developer

JP Mateo(jpmateo022@gmail.com)

Dependencies

~38–53MB
~1M SLoC