aboutsummaryrefslogtreecommitdiff
path: root/src/nix/upgrade-nix.cc
blob: ae314a7c6b0c20be16c6b021f55c37dcc369dfcc (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
#include "command.hh"
#include "common-args.hh"
#include "store-api.hh"
#include "filetransfer.hh"
#include "eval.hh"
#include "attr-path.hh"
#include "names.hh"
#include "progress-bar.hh"

using namespace nix;

struct CmdUpgradeNix : MixDryRun, StoreCommand
{
    Path profileDir;
    std::string storePathsUrl = "https://github.com/NixOS/nixpkgs/raw/master/nixos/modules/installer/tools/nix-fallback-paths.nix";

    CmdUpgradeNix()
    {
        addFlag({
            .longName = "profile",
            .shortName = 'p',
            .description = "The path to the Nix profile to upgrade.",
            .labels = {"profile-dir"},
            .handler = {&profileDir}
        });

        addFlag({
            .longName = "nix-store-paths-url",
            .description = "The URL of the file that contains the store paths of the latest Nix release.",
            .labels = {"url"},
            .handler = {&storePathsUrl}
        });
    }

    std::string description() override
    {
        return "upgrade Nix to the latest stable version";
    }

    std::string doc() override
    {
        return
          #include "upgrade-nix.md"
          ;
    }

    Category category() override { return catNixInstallation; }

    void run(ref<Store> store) override
    {
        evalSettings.pureEval = true;

        if (profileDir == "")
            profileDir = getProfileDir(store);

        printInfo("upgrading Nix in profile '%s'", profileDir);

        auto storePath = getLatestNix(store);

        auto version = DrvName(storePath.name()).version;

        if (dryRun) {
            stopProgressBar();
            warn("would upgrade to version %s", version);
            return;
        }

        {
            Activity act(*logger, lvlInfo, actUnknown, fmt("downloading '%s'...", store->printStorePath(storePath)));
            store->ensurePath(storePath);
        }

        {
            Activity act(*logger, lvlInfo, actUnknown, fmt("verifying that '%s' works...", store->printStorePath(storePath)));
            auto program = store->printStorePath(storePath) + "/bin/nix-env";
            auto s = runProgram(program, false, {"--version"});
            if (s.find("Nix") == std::string::npos)
                throw Error("could not verify that '%s' works", program);
        }

        stopProgressBar();

        {
            Activity act(*logger, lvlInfo, actUnknown,
                fmt("installing '%s' into profile '%s'...", store->printStorePath(storePath), profileDir));
            runProgram(settings.nixBinDir + "/nix-env", false,
                {"--profile", profileDir, "-i", store->printStorePath(storePath), "--no-sandbox"});
        }

        printInfo(ANSI_GREEN "upgrade to version %s done" ANSI_NORMAL, version);
    }

    /* Return the profile in which Nix is installed. */
    Path getProfileDir(ref<Store> store)
    {
        Path where;

        for (auto & dir : tokenizeString<Strings>(getEnv("PATH").value_or(""), ":"))
            if (pathExists(dir + "/nix-env")) {
                where = dir;
                break;
            }

        if (where == "")
            throw Error("couldn't figure out how Nix is installed, so I can't upgrade it");

        printInfo("found Nix in '%s'", where);

        if (hasPrefix(where, "/run/current-system"))
            throw Error("Nix on NixOS must be upgraded via 'nixos-rebuild'");

        Path profileDir = dirOf(where);

        // Resolve profile to /nix/var/nix/profiles/<name> link.
        while (canonPath(profileDir).find("/profiles/") == std::string::npos && isLink(profileDir))
            profileDir = readLink(profileDir);

        printInfo("found profile '%s'", profileDir);

        Path userEnv = canonPath(profileDir, true);

        if (baseNameOf(where) != "bin" ||
            !hasSuffix(userEnv, "user-environment"))
            throw Error("directory '%s' does not appear to be part of a Nix profile", where);

        if (!store->isValidPath(store->parseStorePath(userEnv)))
            throw Error("directory '%s' is not in the Nix store", userEnv);

        return profileDir;
    }

    /* Return the store path of the latest stable Nix. */
    StorePath getLatestNix(ref<Store> store)
    {
        Activity act(*logger, lvlInfo, actUnknown, "querying latest Nix version");

        // FIXME: use nixos.org?
        auto req = FileTransferRequest(storePathsUrl);
        auto res = getFileTransfer()->download(req);

        auto state = std::make_unique<EvalState>(Strings(), store);
        auto v = state->allocValue();
        state->eval(state->parseExprFromString(res.data, "/no-such-path"), *v);
        Bindings & bindings(*state->allocBindings(0));
        auto v2 = findAlongAttrPath(*state, settings.thisSystem, bindings, *v).first;

        return store->parseStorePath(state->forceString(*v2, noPos, "While evaluating the path tho latest nix version: "));
    }
};

static auto rCmdUpgradeNix = registerCommand<CmdUpgradeNix>("upgrade-nix");