projects/guix·blob kernel-updates · refs

134 lines · 4.7 KiB

1;;; GNU Guix --- Functional package management for GNU
2;;; Copyright © 2019 David Thompson <[email protected]>
3;;; Copyright © 2019 Jakob L. Kreuze <[email protected]>
4;;;
5;;; This file is part of GNU Guix.
6;;;
7;;; GNU Guix is free software; you can redistribute it and/or modify it
8;;; under the terms of the GNU General Public License as published by
9;;; the Free Software Foundation; either version 3 of the License, or (at
10;;; your option) any later version.
11;;;
12;;; GNU Guix is distributed in the hope that it will be useful, but
13;;; WITHOUT ANY WARRANTY; without even the implied warranty of
14;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15;;; GNU General Public License for more details.
16;;;
17;;; You should have received a copy of the GNU General Public License
18;;; along with GNU Guix. If not, see <http://www.gnu.org/licenses/>.
19
20;;; Commentary:
21;;;
22;;; This module provides the types used to declare individual machines in a
23;;; heterogeneous Guix deployment. The interface allows users to specify system
24;;; configurations and the means by which resources should be provisioned on a
25;;; per-host basis.
26;;;
27;;; Code:
28
29(define-module (gnu machine)
30 #:use-module (gnu system)
31 #:use-module (guix derivations)
32 #:use-module (guix monads)
33 #:use-module (guix records)
34 #:use-module (guix store)
35 #:use-module ((guix diagnostics) #:select (source-properties->location))
36 #:use-module (srfi srfi-35)
37 #:export (environment-type
38 environment-type?
39 environment-type-name
40 environment-type-description
41 environment-type-location
42
43 machine
44 machine?
45
46 machine-operating-system
47 machine-environment
48 machine-configuration
49 machine-display-name
50
51 deploy-machine
52 roll-back-machine
53 machine-remote-eval
54
55 &deploy-error
56 deploy-error?
57 deploy-error-should-roll-back
58 deploy-error-captured-args))
59
60
61;;;
62;;; Declarations for resources that can be provisioned.
63;;;
64
65(define-record-type* <environment-type> environment-type
66 make-environment-type
67 environment-type?
68
69 ;; Interface to the environment type's deployment code. Each procedure
70 ;; should take the same arguments as the top-level procedure of this file
71 ;; that shares the same name. For example, 'machine-remote-eval' should be
72 ;; of the form '(machine-remote-eval machine exp)'.
73 (machine-remote-eval environment-type-machine-remote-eval) ; procedure
74 (deploy-machine environment-type-deploy-machine) ; procedure
75 (roll-back-machine environment-type-roll-back-machine) ; procedure
76
77 ;; Metadata.
78 (name environment-type-name) ; symbol
79 (description environment-type-description ; string
80 (default #f))
81 (location environment-type-location ; <location>
82 (default (and=> (current-source-location)
83 source-properties->location))
84 (innate)))
85
86
87;;;
88;;; Declarations for machines in a deployment.
89;;;
90
91(define-record-type* <machine> machine make-machine
92 machine?
93 (operating-system %machine-operating-system); <operating-system>
94 (environment machine-environment) ; symbol
95 (configuration machine-configuration ; configuration object
96 (default #f))) ; specific to environment
97
98(define (machine-operating-system machine)
99 "Return the operating system of MACHINE."
100 (operating-system-with-provenance
101 (%machine-operating-system machine)))
102
103(define (machine-display-name machine)
104 "Return the host-name identifying MACHINE."
105 (operating-system-host-name (machine-operating-system machine)))
106
107(define (machine-remote-eval machine exp)
108 "Evaluate EXP, a gexp, on MACHINE. Ensure that all the elements EXP refers to
109are built and deployed to MACHINE beforehand."
110 (let ((environment (machine-environment machine)))
111 ((environment-type-machine-remote-eval environment) machine exp)))
112
113(define (deploy-machine machine)
114 "Monadic procedure transferring the new system's OS closure to the remote
115MACHINE, activating it on MACHINE and switching MACHINE to the new generation."
116 (let ((environment (machine-environment machine)))
117 ((environment-type-deploy-machine environment) machine)))
118
119(define (roll-back-machine machine)
120 "Monadic procedure rolling back to the previous system generation on
121MACHINE. Return the number of the generation that was current before switching
122and the new generation number."
123 (let ((environment (machine-environment machine)))
124 ((environment-type-roll-back-machine environment) machine)))
125
126
127;;;
128;;; Error types.
129;;;
130
131(define-condition-type &deploy-error &error
132 deploy-error?
133 (should-roll-back deploy-error-should-roll-back)
134 (captured-args deploy-error-captured-args))