aboutsummaryrefslogtreecommitdiff
path: root/src/nix/search.cc
blob: 5ccf1b7cf529db903c3c1e743f78a1ec3a9bf842 (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
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
#include "command.hh"
#include "globals.hh"
#include "eval.hh"
#include "eval-inline.hh"
#include "names.hh"
#include "get-drvs.hh"
#include "common-args.hh"
#include "json.hh"
#include "json-to-value.hh"

#include <regex>
#include <fstream>

using namespace nix;

std::string hilite(const std::string & s, const std::smatch & m)
{
    return
        m.empty()
        ? s
        : std::string(m.prefix())
          + ANSI_RED + std::string(m.str()) + ANSI_NORMAL
          + std::string(m.suffix());
}

struct CmdSearch : SourceExprCommand, MixJSON
{
    std::string re;

    bool writeCache = true;
    bool useCache = true;

    CmdSearch()
    {
        expectArg("regex", &re, true);

        mkFlag()
            .longName("update-cache")
            .shortName('u')
            .description("update the package search cache")
            .handler([&]() { writeCache = true; useCache = false; });

        mkFlag()
            .longName("no-cache")
            .description("do not use or update the package search cache")
            .handler([&]() { writeCache = false; useCache = false; });
    }

    std::string name() override
    {
        return "search";
    }

    std::string description() override
    {
        return "query available packages";
    }

    Examples examples() override
    {
        return {
            Example{
                "To show all available packages:",
                "nix search"
            },
            Example{
                "To show any packages containing 'blender' in its name or description:",
                "nix search blender"
            },
            Example{
                "To search for Firefox and Chromium:",
                "nix search 'firefox|chromium'"
            },
        };
    }

    void run(ref<Store> store) override
    {
        settings.readOnlyMode = true;

        // Empty search string should match all packages
        // Use "^" here instead of ".*" due to differences in resulting highlighting
        // (see #1893 -- libc++ claims empty search string is not in POSIX grammar)
        if (re.empty()) re = "^";

        std::regex regex(re, std::regex::extended | std::regex::icase);

        auto state = getEvalState();

        auto jsonOut = json ? std::make_unique<JSONObject>(std::cout) : nullptr;

        auto sToplevel = state->symbols.create("_toplevel");
        auto sRecurse = state->symbols.create("recurseForDerivations");

        bool fromCache = false;

        std::map<std::string, std::string> results;

        std::function<void(Value *, std::string, bool, JSONObject *)> doExpr;

        doExpr = [&](Value * v, std::string attrPath, bool toplevel, JSONObject * cache) {
            debug("at attribute '%s'", attrPath);

            try {

                state->forceValue(*v);

                if (v->type == tLambda && toplevel) {
                    Value * v2 = state->allocValue();
                    state->autoCallFunction(*state->allocBindings(1), *v, *v2);
                    v = v2;
                    state->forceValue(*v);
                }

                if (state->isDerivation(*v)) {

                    DrvInfo drv(*state, attrPath, v->attrs);

                    DrvName parsed(drv.queryName());

                    std::smatch attrPathMatch;
                    std::regex_search(attrPath, attrPathMatch, regex);

                    auto name = parsed.name;
                    std::smatch nameMatch;
                    std::regex_search(name, nameMatch, regex);

                    std::string description = drv.queryMetaString("description");
                    std::replace(description.begin(), description.end(), '\n', ' ');
                    std::smatch descriptionMatch;
                    std::regex_search(description, descriptionMatch, regex);

                    if (!attrPathMatch.empty()
                        || !nameMatch.empty()
                        || !descriptionMatch.empty())
                    {
                        if (json) {

                            auto jsonElem = jsonOut->object(attrPath);

                            jsonElem.attr("pkgName", parsed.name);
                            jsonElem.attr("version", parsed.version);
                            jsonElem.attr("description", description);

                        } else {
                            results[attrPath] = fmt(
                                "Attribute name: %s\n"
                                "Package name: %s\n"
                                "Version: %s\n"
                                "Description: %s\n",
                                hilite(attrPath, attrPathMatch),
                                hilite(name, nameMatch),
                                parsed.version,
                                hilite(description, descriptionMatch));
                        }
                    }

                    if (cache) {
                        cache->attr("type", "derivation");
                        cache->attr("name", drv.queryName());
                        cache->attr("system", drv.querySystem());
                        if (description != "") {
                            auto meta(cache->object("meta"));
                            meta.attr("description", description);
                        }
                    }
                }

                else if (v->type == tAttrs) {

                    if (!toplevel) {
                        auto attrs = v->attrs;
                        Bindings::iterator j = attrs->find(sRecurse);
                        if (j == attrs->end() || !state->forceBool(*j->value, *j->pos)) {
                            debug("skip attribute '%s'", attrPath);
                            return;
                        }
                    }

                    bool toplevel2 = false;
                    if (!fromCache) {
                        Bindings::iterator j = v->attrs->find(sToplevel);
                        toplevel2 = j != v->attrs->end() && state->forceBool(*j->value, *j->pos);
                    }

                    for (auto & i : *v->attrs) {
                        auto cache2 =
                            cache ? std::make_unique<JSONObject>(cache->object(i.name)) : nullptr;
                        doExpr(i.value,
                            attrPath == "" ? (std::string) i.name : attrPath + "." + (std::string) i.name,
                            toplevel2 || fromCache, cache2 ? cache2.get() : nullptr);
                    }
                }

            } catch (AssertionError & e) {
            } catch (Error & e) {
                if (!toplevel) {
                    e.addPrefix(fmt("While evaluating the attribute '%s':\n", attrPath));
                    throw;
                }
            }
        };

        Path jsonCacheFileName = getCacheDir() + "/nix/package-search.json";

        if (useCache && pathExists(jsonCacheFileName)) {

            warn("using cached results; pass '-u' to update the cache");

            Value vRoot;
            parseJSON(*state, readFile(jsonCacheFileName), vRoot);

            fromCache = true;

            doExpr(&vRoot, "", true, nullptr);
        }

        else {
            createDirs(dirOf(jsonCacheFileName));

            Path tmpFile = fmt("%s.tmp.%d", jsonCacheFileName, getpid());

            std::ofstream jsonCacheFile;

            try {
                // iostream considered harmful
                jsonCacheFile.exceptions(std::ofstream::failbit);
                jsonCacheFile.open(tmpFile);

                auto cache = writeCache ? std::make_unique<JSONObject>(jsonCacheFile, false) : nullptr;

                doExpr(getSourceExpr(*state), "", true, cache.get());

            } catch (std::exception &) {
                /* Fun fact: catching std::ios::failure does not work
                   due to C++11 ABI shenanigans.
                   https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66145 */
                if (!jsonCacheFile)
                    throw Error("error writing to %s", tmpFile);
            }

            if (writeCache && rename(tmpFile.c_str(), jsonCacheFileName.c_str()) == -1)
                throw SysError("cannot rename '%s' to '%s'", tmpFile, jsonCacheFileName);
        }

        for (auto el : results) std::cout << el.second << "\n";

    }
};

static RegisterCommand r1(make_ref<CmdSearch>());