Modular, context-aware and aspect-oriented dendritic Nix configurations.
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den.oeiuwq.com
configurations
den
dendritic
nix
aspect
oriented
Dedup includes on ctxApply (#185)
Fixes #180
authored by
GitHub
0c108ece
b839da13
+90
-92
modules/context/types.nix
+90
-92
modules/context/types.nix
···
1
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# den.ctx — Declarative context definitions.
2
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#
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# A context is an attribute set whose attrNames (not values) determine
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# which parametric functions match. den.ctx provides named context
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# types with declarative transformations and aspect lookup.
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#
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# Named contexts carry semantic meaning beyond their structure.
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# ctx.host { host } and ctx.hm-host { host } hold the same data,
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# but hm-host guarantees home-manager support was validated —
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# following transform-don't-validate: you cannot obtain an hm-host
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# unless all detection criteria passed.
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#
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# Context types are independent of NixOS. Den can be used as a library
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# for any domain configurable through Nix (cloud infra, containers,
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# helm charts, etc). The OS framework is one implementation on top of
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# this context+aspects library.
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#
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# Shape of a context definition:
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#
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# den.ctx.foobar = {
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# desc = "The {foo,bar} context";
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# conf = { foo, bar }: den.aspects.${foo}._.${bar};
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# includes = [ <parametric aspects for this context> ];
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# into = {
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# baz = { foo, bar }: lib.singleton { baz = 22; };
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# };
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# };
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#
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# A context type is callable (it is a functor):
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#
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# aspect = den.ctx.foobar { foo = "hello"; bar = "world"; };
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#
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# ctxApply produces an aspect that includes: owned configs from the
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# context type itself, the located aspect via conf, and all recursive
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# transformations via into.
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#
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# Transformations have type: source -> [ target ]. This allows fan-out
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# (one host producing many { host, user } pairs via map) and conditional
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# propagation (lib.optional for detection gates like hm-host).
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#
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# den.default is an alias for den.ctx.default. Every context type
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# transforms into default, so den.default.includes runs at every
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# pipeline stage. Use take.exactly to restrict matching.
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#
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# See os.nix, defaults.nix and provides/home-manager/ for built-in
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# context types.
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{ den, lib, ... }:
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let
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inherit (den.lib) parametric take;
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inherit (den.lib.aspects.types) providerType;
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ctxType = lib.types.submodule {
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freeformType = lib.types.lazyAttrsOf lib.types.deferredModule;
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options = {
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desc = lib.mkOption {
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description = "Context description";
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type = lib.types.str;
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default = "";
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};
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conf = lib.mkOption {
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description = "Obtain a configuration aspect for context";
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type = lib.types.functionTo providerType;
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default = { };
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};
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into = lib.mkOption {
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description = "Context transformations";
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type = lib.types.lazyAttrsOf (lib.types.functionTo (lib.types.listOf lib.types.raw));
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default = { };
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};
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includes = lib.mkOption {
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description = "List of parametric aspects to include for this context";
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type = lib.types.listOf providerType;
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default = [ ];
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};
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__functor = lib.mkOption {
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description = "Apply context. Returns a aspect with all dependencies.";
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type = lib.types.functionTo (lib.types.functionTo providerType);
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readOnly = true;
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internal = true;
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visible = false;
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default = ctxApply;
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};
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};
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};
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cleanCtx =
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ctx:
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builtins.removeAttrs ctx [
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"desc"
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"conf"
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"into"
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"__functor"
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];
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# Given a context, returns an aspect that also includes
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# the result of all context propagation.
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ctxApply =
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self: ctx:
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let
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myself = parametric.fixedTo ctx (cleanCtx self);
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located = self.conf ctx;
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adapted = lib.mapAttrsToList (name: into: map den.ctx.${name} (into ctx)) self.into;
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in
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{
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includes = lib.flatten [
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myself
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located
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adapted
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];
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};
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in
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{
···
1
{ den, lib, ... }:
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let
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inherit (den.lib) parametric;
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inherit (den.lib.aspects.types) providerType;
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ctxType = lib.types.submodule (
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{ name, ... }:
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{
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freeformType = lib.types.lazyAttrsOf lib.types.deferredModule;
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options = {
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name = lib.mkOption {
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description = "Context type name";
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type = lib.types.str;
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default = name;
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};
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desc = lib.mkOption {
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description = "Context description";
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type = lib.types.str;
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default = "";
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};
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conf = lib.mkOption {
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description = "Obtain a configuration aspect for context";
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type = lib.types.functionTo providerType;
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default = { };
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};
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into = lib.mkOption {
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description = "Context transformations";
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type = lib.types.lazyAttrsOf (lib.types.functionTo (lib.types.listOf lib.types.raw));
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default = { };
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};
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includes = lib.mkOption {
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description = "Parametric aspects to include for this context";
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type = lib.types.listOf providerType;
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default = [ ];
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};
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__functor = lib.mkOption {
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description = "Apply context with dedup across into targets.";
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type = lib.types.functionTo (lib.types.functionTo providerType);
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readOnly = true;
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internal = true;
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visible = false;
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default = ctxApply;
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};
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};
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}
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);
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cleanCtx =
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ctx:
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builtins.removeAttrs ctx [
51
+
"name"
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"desc"
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"conf"
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"into"
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"__functor"
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];
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collectPairs =
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self: ctx:
60
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[
61
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{
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inherit ctx;
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ctxDef = self;
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}
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]
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++ lib.concatLists (
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lib.mapAttrsToList (n: into: lib.concatMap (v: collectPairs den.ctx.${n} v) (into ctx)) self.into
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);
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+
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dedupIncludes =
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let
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go =
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acc: remaining:
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if remaining == [ ] then
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acc.result
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else
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let
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p = builtins.head remaining;
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rest = builtins.tail remaining;
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n = p.ctxDef.name;
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clean = cleanCtx p.ctxDef;
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isFirst = !(acc.seen ? ${n});
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items =
84
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if isFirst then
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[
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(parametric.fixedTo p.ctx clean)
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(p.ctxDef.conf p.ctx)
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]
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else
90
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[
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(parametric.atLeast clean p.ctx)
92
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(p.ctxDef.conf p.ctx)
93
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];
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in
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go {
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seen = acc.seen // {
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${n} = true;
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};
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result = acc.result ++ items;
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} rest;
101
in
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pairs:
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go {
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seen = { };
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result = [ ];
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} pairs;
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+
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ctxApply = self: ctx: { includes = dedupIncludes (collectPairs self ctx); };
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in
111
{
-13
templates/ci/modules/features/context/host-propagation.nix
-13
templates/ci/modules/features/context/host-propagation.nix
···
4
# This test uses the `funny.names` test option to
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# demostrate different places and context-aspects that
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# can contribute configurations to the host.
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#
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# Note that both host and user aspects include default
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# and because of that, default owned and static values
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# might be duplicated. This is why users are NOT adviced
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# to abuse den.default.
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#
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# The behaviour is correct, but using den.default for
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# everything without care will cause deplication problems.
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# Instead, users should include either directly on the host
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# or by using `den.ctx.host` or `den.ctx.user`.
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flake.tests.ctx-transformation.test-host = denTest (
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{
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den,
···
161
162
expected = [
163
"default-anyctx {aspect-chain,class}"
164
-
"default-anyctx {aspect-chain,class}"
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"default-anyctx {host,user}"
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"default-anyctx {host}"
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···
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"default-host-lax {host}"
171
172
"default-owned"
173
-
"default-owned"
174
175
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"default-static"
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"default-static"
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178
"default-user-lax {host,user}"
···
4
# This test uses the `funny.names` test option to
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# demostrate different places and context-aspects that
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# can contribute configurations to the host.
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flake.tests.ctx-transformation.test-host = denTest (
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{
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den,
···
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152
expected = [
153
"default-anyctx {aspect-chain,class}"
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"default-anyctx {host,user}"
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"default-anyctx {host}"
156
···
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"default-host-lax {host}"
160
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"default-owned"
162
163
"default-static"
164
165
"default-user-lax {host,user}"
+145
templates/ci/modules/features/deadbugs/static-include-dup-package.nix
+145
templates/ci/modules/features/deadbugs/static-include-dup-package.nix
···
86
}
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);
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+
flake.tests.deadbugs.dups.test-default-owned-package = denTest (
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{
91
+
den,
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+
lib,
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+
igloo,
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+
...
95
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}:
96
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{
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den.hosts.x86_64-linux.igloo.users.tux = { };
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+
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den.default.nixos =
100
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{ pkgs, ... }:
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{
102
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services.locate.package = pkgs.plocate;
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};
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+
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expr = lib.getName igloo.services.locate.package;
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expected = "plocate";
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}
108
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);
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+
110
+
flake.tests.deadbugs.dups.test-default-static-package = denTest (
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{
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+
den,
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+
lib,
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+
igloo,
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+
...
116
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}:
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{
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den.hosts.x86_64-linux.igloo.users.tux = { };
119
+
120
+
den.default.includes = [
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+
{
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nixos =
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{ pkgs, ... }:
124
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{
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services.locate.package = pkgs.plocate;
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};
127
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}
128
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];
129
+
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expr = lib.getName igloo.services.locate.package;
131
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expected = "plocate";
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}
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);
134
+
135
+
flake.tests.deadbugs.dups.test-default-owned-list = denTest (
136
+
{
137
+
den,
138
+
lib,
139
+
igloo,
140
+
...
141
+
}:
142
+
{
143
+
den.hosts.x86_64-linux.igloo.users.tux = { };
144
+
145
+
den.default.nixos.imports = [
146
+
{
147
+
options.tags = lib.mkOption {
148
+
type = lib.types.listOf lib.types.str;
149
+
default = [ ];
150
+
};
151
+
}
152
+
];
153
+
den.default.nixos.tags = [ "server" ];
154
+
155
+
expr = igloo.tags;
156
+
expected = [ "server" ];
157
+
}
158
+
);
159
+
160
+
flake.tests.deadbugs.dups.test-host-owned-package = denTest (
161
+
{
162
+
den,
163
+
lib,
164
+
igloo,
165
+
...
166
+
}:
167
+
{
168
+
den.hosts.x86_64-linux.igloo.users.tux = { };
169
+
170
+
den.aspects.igloo.nixos =
171
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{ pkgs, ... }:
172
+
{
173
+
services.locate.package = pkgs.plocate;
174
+
};
175
+
176
+
expr = lib.getName igloo.services.locate.package;
177
+
expected = "plocate";
178
+
}
179
+
);
180
+
181
+
flake.tests.deadbugs.dups.test-host-owned-list = denTest (
182
+
{
183
+
den,
184
+
lib,
185
+
igloo,
186
+
...
187
+
}:
188
+
{
189
+
den.hosts.x86_64-linux.igloo.users.tux = { };
190
+
191
+
den.aspects.igloo.nixos.imports = [
192
+
{
193
+
options.tags = lib.mkOption {
194
+
type = lib.types.listOf lib.types.str;
195
+
default = [ ];
196
+
};
197
+
}
198
+
];
199
+
den.aspects.igloo.nixos.tags = [ "server" ];
200
+
201
+
expr = igloo.tags;
202
+
expected = [ "server" ];
203
+
}
204
+
);
205
+
206
+
flake.tests.deadbugs.dups.test-default-list-multi-user = denTest (
207
+
{
208
+
den,
209
+
lib,
210
+
igloo,
211
+
...
212
+
}:
213
+
{
214
+
den.hosts.x86_64-linux.igloo.users = {
215
+
tux = { };
216
+
pingu = { };
217
+
};
218
+
219
+
den.default.nixos.imports = [
220
+
{
221
+
options.tags = lib.mkOption {
222
+
type = lib.types.listOf lib.types.str;
223
+
default = [ ];
224
+
};
225
+
}
226
+
];
227
+
den.default.nixos.tags = [ "server" ];
228
+
229
+
expr = igloo.tags;
230
+
expected = [ "server" ];
231
+
}
232
+
);
233
+
234
}
+21
templates/ci/modules/features/default-includes.nix
+21
templates/ci/modules/features/default-includes.nix
···
2
{
3
flake.tests.default-includes = {
4
5
+
test-setting-host-service-package = denTest (
6
+
{
7
+
den,
8
+
lib,
9
+
igloo,
10
+
...
11
+
}:
12
+
{
13
+
den.hosts.x86_64-linux.igloo.users.tux = { };
14
+
15
+
den.aspects.igloo.nixos =
16
+
{ pkgs, ... }:
17
+
{
18
+
services.locate.package = pkgs.plocate;
19
+
};
20
+
21
+
expr = lib.getName igloo.services.locate.package;
22
+
expected = "plocate";
23
+
}
24
+
);
25
+
26
test-set-hostname-from-host-context = denTest (
27
{ den, igloo, ... }:
28
{