add pgAdmin service (#115)

doc/pgadmin.md

@@ -0,0 +1,18 @@
+# pgAdmin
+
+[pgAdmin] is a feature rich Open Source administration and development platform for PostgreSQL.
+
+[pgAdmin]: https://www.pgadmin.org/
+
+## Getting Started
+
+```nix
+# In `perSystem.process-compose.<name>`
+{
+  services.pgadmin."pgad1" = {
+    enable = true;
+    initialEmail = "email@gmail.com";
+    initialPassword = "password";
+  };
+}
+```

doc/services.md

@@ -18,6 +18,7 @@ short-title: Services
 - [ ] Zookeeper
 - [x] [[grafana]]#
 - [X] [[prometheus]]#
+- [X] [[pgadmin]]#
 - [ ] ...
 
 [gh]: https://github.com/juspay/services-flake

nix/default.nix

@@ -15,5 +15,6 @@ in
     ./zookeeper.nix
     ./grafana.nix
     ./prometheus.nix
+    ./pgadmin.nix
   ];
 }

nix/pgadmin.nix

@@ -0,0 +1,171 @@
+# Based on https://github.com/NixOS/nixpkgs/blob/d53c2037394da6fe98decca417fc8fda64bf2443/nixos/modules/services/admin/pgadmin.nix
+{ pkgs, lib, name, config, ... }:
+let
+  inherit (lib) types;
+
+  _base = with types; [ int bool str ];
+  base = with types; oneOf ([ (listOf (oneOf _base)) (attrsOf (oneOf _base)) ] ++ _base);
+
+  formatAttrset = attr:
+    "{${lib.concatStringsSep "\n" (lib.mapAttrsToList (key: value: "${builtins.toJSON key}: ${formatPyValue value},") attr)}}";
+
+  formatPyValue = value:
+    if builtins.isString value then builtins.toJSON value
+    else if value ? _expr then value._expr
+    else if builtins.isInt value then toString value
+    else if builtins.isBool value then (if value then "True" else "False")
+    else if builtins.isAttrs value then (formatAttrset value)
+    else if builtins.isList value then "[${lib.concatStringsSep "\n" (map (v: "${formatPyValue v},") value)}]"
+    else throw "Unrecognized type";
+
+  formatPy = attrs:
+    lib.concatStringsSep "\n" (lib.mapAttrsToList (key: value: "${key} = ${formatPyValue value}") attrs);
+
+  pyType = with types; attrsOf (oneOf [ (attrsOf base) (listOf base) base ]);
+in
+{
+  options = {
+    enable = lib.mkEnableOption name;
+
+    package = lib.mkPackageOption pkgs "pgadmin4" { };
+
+    host = lib.mkOption {
+      description = lib.mdDoc "Host for pgadmin4 to run on";
+      type = types.str;
+      default = "localhost";
+    };
+
+    port = lib.mkOption {
+      description = lib.mdDoc "Port for pgadmin4 to run on";
+      type = types.port;
+      default = 5050;
+    };
+
+
+    initialEmail = lib.mkOption {
+      description = "Initial email for the pgAdmin account";
+      type = types.str;
+    };
+
+    initialPassword = lib.mkOption {
+      description = "Initial password for the pgAdmin account";
+      type = types.str;
+    };
+
+    minimumPasswordLength = lib.mkOption {
+      description = "Minimum length of the password";
+      type = types.int;
+      default = 6;
+    };
+
+    dataDir = lib.mkOption {
+      type = types.str;
+      default = "./data/${name}";
+      description = "The pgadmin4 data directory";
+    };
+
+    extraDefaultConfig = lib.mkOption {
+      type = pyType;
+      internal = true;
+      readOnly = true;
+      default = {
+        DATA_DIR = {
+          _expr = "os.getenv('PGADMIN_DATADIR')";
+        };
+        DEFAULT_SERVER = config.host;
+        DEFAULT_SERVER_PORT = config.port;
+        PASSWORD_LENGTH_MIN = config.minimumPasswordLength;
+        SERVER_MODE = true;
+        UPGRADE_CHECK_ENABLED = false;
+      };
+    };
+
+    extraConfig = lib.mkOption {
+      type = pyType;
+      default = { };
+      description = "Additional config for pgadmin4";
+    };
+
+    outputs.settings = lib.mkOption {
+      type = types.deferredModule;
+      internal = true;
+      readOnly = true;
+      default = {
+        processes =
+          let
+            pgadminConfig = pkgs.writeTextDir "config_local.py" (
+              "import os\n" + (formatPy
+                (lib.recursiveUpdate config.extraDefaultConfig config.extraConfig))
+            );
+          in
+          {
+            "${name}-init" =
+              let
+                setupScript = pkgs.writeShellApplication {
+                  name = "setup-pgadmin";
+                  runtimeInputs = [ config.package ];
+                  text = ''
+                    export PYTHONPATH="${pgadminConfig}"
+                    PGADMIN_DATADIR="$(readlink -m ${config.dataDir})"
+                    mkdir -p "$PGADMIN_DATADIR"
+                    export PGADMIN_DATADIR
+                    PGADMIN_SETUP_EMAIL=${lib.escapeShellArg config.initialEmail}
+                    export PGADMIN_SETUP_EMAIL
+                    PGADMIN_SETUP_PASSWORD=${lib.escapeShellArg config.initialPassword}
+                    export PGADMIN_SETUP_PASSWORD
+                    if [ -f ${config.package}/bin/.pgadmin4-setup-wrapped ]; then
+                      # pgadmin-7.5 has .pgadmin4-setup-wrapped
+                      ${config.package}/bin/.pgadmin4-setup-wrapped setup
+                    else
+                      # pgadmin-8.2 has .pgadmin4-cli-wrapped
+                      ${config.package}/bin/.pgadmin4-cli-wrapped setup
+                    fi
+                  '';
+                };
+              in
+              {
+                command = setupScript;
+                namespace = name;
+              };
+
+            "${name}" =
+              let
+                startScript = pkgs.writeShellApplication {
+                  name = "start-pgadmin";
+                  runtimeInputs = [ config.package ];
+                  text = ''
+                    export PYTHONPATH="${pgadminConfig}"
+                    PGADMIN_DATADIR="$(readlink -m ${config.dataDir})"
+                    export PGADMIN_DATADIR
+                    PGADMIN_SETUP_EMAIL=${lib.escapeShellArg config.initialEmail}
+                    export PGADMIN_SETUP_EMAIL
+                    PGADMIN_SETUP_PASSWORD=${lib.escapeShellArg config.initialPassword}
+                    export PGADMIN_SETUP_PASSWORD
+                    ${config.package}/bin/.pgadmin4-wrapped
+                  '';
+                };
+              in
+              {
+                command = startScript;
+                readiness_probe = {
+                  http_get = {
+                    host = config.host;
+                    port = config.port;
+                    path = "/misc/ping";
+                  };
+                  initial_delay_seconds = 2;
+                  period_seconds = 10;
+                  timeout_seconds = 4;
+                  success_threshold = 1;
+                  failure_threshold = 5;
+                };
+                namespace = name;
+                depends_on."${name}-init".condition = "process_completed_successfully";
+                # https://github.com/F1bonacc1/process-compose#-auto-restart-if-not-healthy
+                availability.restart = "on_failure";
+              };
+          };
+      };
+    };
+  };
+}

nix/pgadmin_test.nix

@@ -0,0 +1,23 @@
+{ pkgs, config, ... }: {
+
+  services.pgadmin."pgad1" = {
+    enable = true;
+    initialEmail = "email@gmail.com";
+    initialPassword = "password";
+  };
+
+  settings.processes.test =
+    let
+      cfg = config.services.pgadmin."pgad1";
+    in
+    {
+      command = pkgs.writeShellApplication {
+        runtimeInputs = [ cfg.package pkgs.curl pkgs.gnugrep ];
+        text = ''
+          curl http://localhost:5050/misc/ping | grep "PING"
+        '';
+        name = "pgadmin-test";
+      };
+      depends_on."pgad1".condition = "process_healthy";
+    };
+}

test/flake.nix

@@ -17,6 +17,12 @@
           inherit system;
           # Required for elastic search
           config.allowUnfree = true;
+          overlays = [
+            (final: prev: {
+              # Because tests are failing on darwin: https://github.com/juspay/services-flake/pull/115#issuecomment-1970467684
+              pgadmin4 = prev.pgadmin4.overrideAttrs (_: { doInstallCheck = false; });
+            })
+          ];
         };
         process-compose =
           let
@@ -48,6 +54,7 @@
             "${inputs.services-flake}/nix/zookeeper_test.nix"
             "${inputs.services-flake}/nix/grafana_test.nix"
             "${inputs.services-flake}/nix/prometheus_test.nix"
+            "${inputs.services-flake}/nix/pgadmin_test.nix"
           ]);
       };
     };