Catch the guix available when built

And use it for the hosting the inferiors, rather than computing the guix
package at runtime. This simplifies the behaviour when the Guix Data Service
is deployed as a Guix package.

3 files changed, 26 insertions, 12 deletions

diff --git a/configure.ac b/configure.ac
index 7952277..a50d90b 100644
--- a/configure.ac
+++ b/configure.ac
@@ -35,6 +35,8 @@ guilemoduledir="${datarootdir}/guile/site/${GUILE_EFFECTIVE_VERSION}"
 AC_SUBST([guilemoduledir])
 AC_SUBST([GUILE_EFFECTIVE_VERSION])
 
+AC_PATH_PROG([guix], [guix])
+
 AC_PATH_PROG([sqitch], [sqitch])
 AC_PATH_PROG([psql], [psql])
 
diff --git a/guix-data-service/config.scm.in b/guix-data-service/config.scm.in
index 12572c2..20323c6 100644
--- a/guix-data-service/config.scm.in
+++ b/guix-data-service/config.scm.in
@@ -33,6 +33,8 @@
            (host        . "localhost")
            (port        . 8765)
 
+           (guix        . "@guix@")
+
            (sqitch      . "@sqitch@")
            (sqitch-psql . "@psql@")
            (sqitch-plan . ,(let ((installed-plan
diff --git a/guix-data-service/jobs/load-new-guix-revision.scm b/guix-data-service/jobs/load-new-guix-revision.scm
index c51e91e..5ce8c4c 100644
--- a/guix-data-service/jobs/load-new-guix-revision.scm
+++ b/guix-data-service/jobs/load-new-guix-revision.scm
@@ -12,6 +12,7 @@
   #:use-module (guix packages)
   #:use-module (guix derivations)
   #:use-module (guix build utils)
+  #:use-module (guix-data-service config)
   #:use-module (guix-data-service model package)
   #:use-module (guix-data-service model git-repository)
   #:use-module (guix-data-service model guix-revision)
@@ -245,18 +246,27 @@
       (if (and store-path
                (file-exists? store-path))
           store-path
-          (begin
-            (invalidate-derivation-caches!)
-            (hash-clear! (@@ (guix packages) %derivation-cache))
-            (let* ((guix-package (@ (gnu packages package-management)
-                                    guix))
-                   (derivation (package-derivation store guix-package)))
-              (build-derivations store (list derivation))
-
-              (let ((new-store-path
-                     (derivation->output-path derivation)))
-                (set! store-path new-store-path)
-                new-store-path)))))))
+          (let ((config-guix (%config 'guix)))
+            (if (and (file-exists? config-guix)
+                     (string-prefix? "/gnu/store/" config-guix))
+                (begin
+                  (set! store-path
+                    (dirname
+                     (dirname
+                      (%config 'guix))))
+                  store-path)
+                (begin
+                  (invalidate-derivation-caches!)
+                  (hash-clear! (@@ (guix packages) %derivation-cache))
+                  (let* ((guix-package (@ (gnu packages package-management)
+                                          guix))
+                         (derivation (package-derivation store guix-package)))
+                    (build-derivations store (list derivation))
+
+                    (let ((new-store-path
+                           (derivation->output-path derivation)))
+                      (set! store-path new-store-path)
+                      new-store-path)))))))))
 
 (define (nss-certs-store-path store)
   (let* ((nss-certs-package (@ (gnu packages certs)