Development and contribution guidelines (#112)

---------

Co-authored-by: Sridhar Ratnakumar <srid@srid.ca>
Co-authored-by: Sridhar Ratnakumar <3998+srid@users.noreply.github.com>

.gitignore

@@ -1,3 +1,5 @@
 .direnv
 # created when `just test <service>` is used
 /result
+# created when `just run <service>` is used
+/test/data

README.md

@@ -2,19 +2,13 @@
 
 # services-flake
 
-NixOS-like services for Nix flakes, as a [process-compose-flake](https://github.com/Platonic-Systems/process-compose-flake) module (based on flake-parts).
+Declarative, composable, and reproducible services for Nix development environment, as a [process-compose-flake](https://github.com/Platonic-Systems/process-compose-flake) module (based on [flake-parts](https://flake.parts)). Enabling users to have NixOS-like service on MacOS and Linux.
 
-![](./doc/services-flake/demo.gif)
+![Demo](./doc/demo.gif)
 
 ## Getting Started
 
-```sh
-$ nix flake new --template github:juspay/services-flake ./my-project
-$ cd my-project
-$ nix run
-```
-
-Or see `./test/flake.nix`
+See <https://community.flake.parts/services-flake/start>
 
 ## Services available
 
@@ -28,10 +22,9 @@ The `dataDir` of these services tend to take *relative* paths, which are usually
 
 To discuss the project, please [join our Zulip](https://nixos.zulipchat.com/#narrow/stream/414011-services-flake).
 
-## Contributing
+## Contributing & Development
 
-- If you are adding a *new* service, see https://github.com/cachix/devenv/tree/main/src/modules/services for inspiration.
-- For contributing to docs, see https://github.com/flake-parts/community.flake.parts#guidelines-for-writing-docs
+See <https://community.flake.parts/services-flake/contributing>
 
 ## Credits
 
@@ -41,4 +34,4 @@ Thanks to [the devenv project](https://github.com/cachix/devenv/tree/main/src/mo
 
 ### Why not re-use devenv service modules?
 
-This is currently not possible (nor prioritized by the devenv project), which is why we must create our own services. See https://github.com/cachix/devenv/issues/75
+This is currently not possible (nor prioritized by the devenv project), which is why we must create our own services. See <https://github.com/cachix/devenv/issues/75>

doc/contributing.md

@@ -0,0 +1,75 @@
+---
+order: 10
+---
+
+# Contributing
+
+{#devshell}
+## Development Shell
+
+A Nix dev shell is available, providing `nixpkgs-fmt` and `just`. To enter the dev shell, run:
+
+```sh
+nix develop .#dev
+```
+
+An `.envrc` is also provided, so it is recommended to use `direnv` to automatically enter the dev shell when you `cd` into the project directory. See [this tutorial](https://nixos.asia/en/direnv).
+
+{#new-service}
+## Adding a new service
+
+The project repository is structure to make addition of new services easy. Here's how to add a new service:
+
+> [!info]
+> See <https://github.com/cachix/devenv/tree/main/src/modules/services> for inspiration.
+> 
+> If you don't find a new service there, see <https://github.com/NixOS/nixpkgs/tree/master/nixos/modules/services>.
+
+- Create a new file `./nix/<service-name>.nix` file (see [./nix/redis.nix](https://github.com/juspay/services-flake/blob/main/nix/redis.nix) for inspiration)
+- Add the service to the list in [./nix/default.nix](https://github.com/juspay/services-flake/blob/main/nix/default.nix).
+- Create a new test file `./nix/<service-name>_test.nix` (see [./nix/redis_test.nix](https://github.com/juspay/services-flake/blob/main/nix/redis_test.nix)).
+- Add the test to [./test/flake.nix](https://github.com/juspay/services-flake/blob/main/test/flake.nix).
+
+{#run-service}
+### Run the service
+
+```sh
+just run <service-name>
+```
+
+{#run-tests}
+### Run the tests for the service
+
+The previous command will run the services but not the tests. To run the tests, use:
+
+```sh
+just test <service-name>
+```
+
+or test all services:
+
+```sh
+just test-all
+```
+
+{#service-doc}
+### Add documentation for the new service
+
+It is important to add documentation along with any new services you are contributing. Create a new file `./doc/<service-name>.md` (see [[clickhouse]] for example) and add the service to the list in [[services]].
+
+> [!note]
+> It is recommended to add documentation for non-trivial tasks. For example, grafana documentation mentions [how to change the default database backend](https://community.flake.parts/services-flake/grafana#change-database).
+
+
+
+{#docs}
+## Documentation
+
+For contributing to docs, see <https://github.com/flake-parts/community.flake.parts#guidelines-for-writing-docs>
+
+We use [emanote](https://emanote.srid.ca/) to render our documentation. The source files are in the `doc` directory. To run the docs, use:
+
+```sh
+just doc # Or, `cd doc && nix run`
+```
+

doc/grafana.md

@@ -22,19 +22,21 @@ By default, Grafana stores data in the `sqlite3` [database](https://grafana.com/
 To change the database to `postgres`, we can use the following config:
 
 ```nix
-    services.postgres.pg1 = {
-      enable = true;
-      listen_addresses = "127.0.0.1";
-      initialScript.after = "CREATE USER root SUPERUSER;";
-    };
-    services.grafana.gf1 = {
-      enable = true;
-      extraConf.database = with config.services.postgres.pg1; {
-        type = "postgres";
-        host = "${listen_addresses}:${builtins.toString port}";
-        name = "postgres"; # database name
-      };
-    };
-    settings.processes."gf1".depends_on."pg1".condition = "process_healthy";
+{
+  services.postgres.pg1 = {
+    enable = true;
+    listen_addresses = "127.0.0.1";
+    initialScript.after = "CREATE USER root SUPERUSER;";
+  };
+  services.grafana.gf1 = {
+    enable = true;
+    extraConf.database = with config.services.postgres.pg1; {
+      type = "postgres";
+      host = "${listen_addresses}:${builtins.toString port}";
+      name = "postgres"; # database name
     };
+  };
+  settings.processes."gf1".depends_on."pg1".condition = "process_healthy";
+  };
+}
 ```

doc/index.md

@@ -9,9 +9,9 @@ emanote:
 
 # Running services using `services-flake`
 
-[services-flake][gh] is a [flake-parts](https://flake.parts/) module providing [NixOS-like services](https://github.com/NixOS/nixpkgs/tree/master/nixos/modules/services) for [Nix flakes](https://nixos.asia/en/flakes), enabling the users to use same configuration for local development across platforms.
+[services-flake][gh] provides declarative, composable, and reproducible services for Nix development environment, as a [process-compose-flake](https://github.com/Platonic-Systems/process-compose-flake) module (based on [flake-parts](https://flake.parts)). Enabling users to have NixOS-like service on MacOS and Linux.
 
-It builds on top of the [process-compose-flake](https://community.flake.parts/process-compose-flake) module which allows running arbitrary processes in the devShell environment.
+It builds on top of the [process-compose-flake](https://community.flake.parts/process-compose-flake) module which allows running arbitrary processes declared in Nix.
 
 See:
 - [[start]]#

doc/services.md

@@ -8,7 +8,7 @@ short-title: Services
 > This list denotes the progress of documentation, not implementation. See full list of implemented services at [gh].
 
 - [ ] Apache Kafka
-- [ ] [[clickhouse]]#
+- [x] [[clickhouse]]#
 - [ ] Elasticsearch
 - [ ] MySQL
 - [ ] Nginx
@@ -16,7 +16,7 @@ short-title: Services
 - [ ] Redis
 - [ ] Redis Cluster
 - [ ] Zookeeper
-- [ ] [[grafana]]#
+- [x] [[grafana]]#
 - [ ] ...
 
 [gh]: https://github.com/juspay/services-flake

justfile

@@ -1,3 +1,4 @@
+# List all the just commands
 default:
     @just --list
 
@@ -17,3 +18,11 @@ test-all:
 # Run native test for a specific service
 test service:
     nix build ./test#checks.$(nix eval --impure --expr "builtins.currentSystem").{{service}} --override-input services-flake . -L
+
+# Run doc server with hot-reload
+doc:
+    cd ./doc && nix run
+
+# Run service whose configuration is defined in `<service>_test.nix`
+run service:
+    cd test && nix run .#{{service}} --override-input services-flake ../