Service mesh support for Elixir.
Meshx is released as group of separate Elixir packages, summary for each package is provided below.
MeshxConsul is a service mesh adapter implementing Meshx.ServiceMesh behaviour using HashiCorp Consul as an external service mesh solution. Package manages mesh service and upstream endpoints, which are later consumed by user service providers and upstream clients.
MeshxConsul by using external dependencies, Consul as control plane and Envoy/other proxy as data plane, complements user client/server applications with powerful service mesh features:
- mTLS connections,
- service-to-service permissions: intentions,
- mesh service health checks,
- load balancing,
- observability and UI visualisations,
- multi datacenter communication using gateways.
Meshx packages using MeshxConsul service mesh adapter to deliver end-user functionality are:
MeshxRpc- RPC (Remote Procedure Call) functionality,MeshxNode- service mesh distribution module.
MeshxRpc can be considered as alternative to Erlang OTP :erpc (or :rpc) module. MeshxRpc restricts request execution scope to single RPC server module to improve operational node security. MeshxRpc provides built-in features crucial for binary data transfers: chunking user data into smaller blocks to avoid IO socket blocking and transmission error detection with user configurable asynchronously executed block checksum functions.
MeshxRpc is using custom binary communication protocol, hence it doesn't depend on Erlang distribution protocol. MeshxRpc fits best in cases where user application requires execution of plain remote functions and doesn't require remote process management features like process linking or monitoring available only for natively distributed nodes. MeshxRpc can be used with nodes connected with Erlang distribution if justified by package additional features, otherwise OTP :erpc should be used.
MeshxRpc primary objective is to work paired with service mesh adapter (MeshxConsul) as a user mesh service, however it can be used with any other data transport solution, eg. ssh port forwarding or VPN. For special use cases it can work standalone: MeshxRpc server and client running on the same host and sharing common connection socket.
MeshxRpc doesn't offer data encryption, authorization or authentication mechanisms as those are natively provided by service mesh environment.
MeshxNode delivers Erlang style nodes connectivity by registering special "node service" using service mesh adapter. Communication between nodes is realized using service mesh sidecar proxies and upstreams. Data traffic is secured with mTLS, managed by service mesh application control plane (e.g. Consul).
MeshxNode can be considered as alternative to Erlang Port Mapper Daemon (EPMD) and distribution module (usually :inet_tls_dist or :inet_dist).
MeshxNode running on top of service mesh data plane for inter-node communication provides high availability feature for distributed nodes.
Users are free to use any mesh service management features provided by external mesh application or L4 proxy software. Consul service intentions, tokens or ACLs to manage "node service" access permissions might be an interesting feature to consider here.
Meshx package doesn't offer any end-user functionality. Meshx should be used by developers building new service mesh adapters implementing Meshx.ServiceMesh behavior.
Service mesh adapter in practice should be reasonably thin layer between user application using Meshx packages and external software providing service mesh solution. Mesh adapter should use third party application API to implement functionality required by Meshx.ServiceMesh behavior. As described earlier Meshx is released with HashiCorp Consul adapter - MeshxConsul.
Basic MeshxRpc capabilities demonstration with Phoenix LiveView.