From d18ad307fc8084f9b5479e8fc08d4fbc427738c5 Mon Sep 17 00:00:00 2001 From: Martin Fischer Date: Sun, 28 Dec 2025 16:03:35 +0100 Subject: initial commit --- .gitignore | 1 + LICENSE | 19 ++++++++ README.md | 11 +++++ default.nix | 15 ++++++ go.mod | 22 +++++++++ go.sum | 54 ++++++++++++++++++++++ hashes.nix | 3 ++ main.go | 149 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ main_test.go | 63 +++++++++++++++++++++++++ service.nix | 51 ++++++++++++++++++++ 10 files changed, 388 insertions(+) create mode 100644 .gitignore create mode 100644 LICENSE create mode 100644 README.md create mode 100644 default.nix create mode 100644 go.mod create mode 100644 go.sum create mode 100644 hashes.nix create mode 100644 main.go create mode 100644 main_test.go create mode 100644 service.nix diff --git a/.gitignore b/.gitignore new file mode 100644 index 0000000..c4a847d --- /dev/null +++ b/.gitignore @@ -0,0 +1 @@ +/result diff --git a/LICENSE b/LICENSE new file mode 100644 index 0000000..7389b02 --- /dev/null +++ b/LICENSE @@ -0,0 +1,19 @@ +Copyright (c) 2025 Martin Fischer + +Permission is hereby granted, free of charge, to any person obtaining a copy +of this software and associated documentation files (the "Software"), to deal +in the Software without restriction, including without limitation the rights +to use, copy, modify, merge, publish, distribute, sublicense, and/or sell +copies of the Software, and to permit persons to whom the Software is +furnished to do so, subject to the following conditions: + +The above copyright notice and this permission notice shall be included in all +copies or substantial portions of the Software. + +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER +LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, +OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE +SOFTWARE. diff --git a/README.md b/README.md new file mode 100644 index 0000000..d6ebb75 --- /dev/null +++ b/README.md @@ -0,0 +1,11 @@ +# git-grep-exporter + +Prometheus metrics for how many lines in certain git repos match certain regular expressions. + +Only the HEAD of the repositories will be grepped. +The metrics are named `{pattern}_lines` and have `repo` labels. + +I made this to track the amount of TODO and FIXME comments in my repositories +because often while fixing one TODO I end up writing two more and it feels like +it's never ending but surely there's an end? The patterns are fully configurable +so you could also use this to track curse words ... or something else? diff --git a/default.nix b/default.nix new file mode 100644 index 0000000..27d801c --- /dev/null +++ b/default.nix @@ -0,0 +1,15 @@ +{ pkgs ? import {} }: + +pkgs.buildGoModule { + pname = "git-grep-exporter"; + version = "0+git"; + src = pkgs.lib.cleanSource ./.; + vendorHash = (import ./hashes.nix).vendor; + + nativeBuildInputs = with pkgs; [makeWrapper]; + + postInstall = '' + wrapProgram $out/bin/git-grep-exporter \ + --prefix PATH : ${pkgs.lib.makeBinPath [pkgs.gitMinimal]} + ''; +} diff --git a/go.mod b/go.mod new file mode 100644 index 0000000..aa1f500 --- /dev/null +++ b/go.mod @@ -0,0 +1,22 @@ +module push-f.com/git-grep-exporter + +go 1.25.4 + +require ( + github.com/alecthomas/kong v1.13.0 + github.com/google/go-cmp v0.7.0 + github.com/prometheus/client_golang v1.23.2 + github.com/prometheus/common v0.66.1 +) + +require ( + github.com/beorn7/perks v1.0.1 // indirect + github.com/cespare/xxhash/v2 v2.3.0 // indirect + github.com/kr/text v0.2.0 // indirect + github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 // indirect + github.com/prometheus/client_model v0.6.2 // indirect + github.com/prometheus/procfs v0.16.1 // indirect + go.yaml.in/yaml/v2 v2.4.2 // indirect + golang.org/x/sys v0.35.0 // indirect + google.golang.org/protobuf v1.36.8 // indirect +) diff --git a/go.sum b/go.sum new file mode 100644 index 0000000..46a5365 --- /dev/null +++ b/go.sum @@ -0,0 +1,54 @@ +github.com/alecthomas/assert/v2 v2.11.0 h1:2Q9r3ki8+JYXvGsDyBXwH3LcJ+WK5D0gc5E8vS6K3D0= +github.com/alecthomas/assert/v2 v2.11.0/go.mod h1:Bze95FyfUr7x34QZrjL+XP+0qgp/zg8yS+TtBj1WA3k= +github.com/alecthomas/kong v1.13.0 h1:5e/7XC3ugvhP1DQBmTS+WuHtCbcv44hsohMgcvVxSrA= +github.com/alecthomas/kong v1.13.0/go.mod h1:wrlbXem1CWqUV5Vbmss5ISYhsVPkBb1Yo7YKJghju2I= +github.com/alecthomas/repr v0.5.2 h1:SU73FTI9D1P5UNtvseffFSGmdNci/O6RsqzeXJtP0Qs= +github.com/alecthomas/repr v0.5.2/go.mod h1:Fr0507jx4eOXV7AlPV6AVZLYrLIuIeSOWtW57eE/O/4= +github.com/beorn7/perks v1.0.1 h1:VlbKKnNfV8bJzeqoa4cOKqO6bYr3WgKZxO8Z16+hsOM= +github.com/beorn7/perks v1.0.1/go.mod h1:G2ZrVWU2WbWT9wwq4/hrbKbnv/1ERSJQ0ibhJ6rlkpw= +github.com/cespare/xxhash/v2 v2.3.0 h1:UL815xU9SqsFlibzuggzjXhog7bL6oX9BbNZnL2UFvs= +github.com/cespare/xxhash/v2 v2.3.0/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs= +github.com/creack/pty v1.1.9/go.mod h1:oKZEueFk5CKHvIhNR5MUki03XCEU+Q6VDXinZuGJ33E= +github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c= +github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38= +github.com/google/go-cmp v0.7.0 h1:wk8382ETsv4JYUZwIsn6YpYiWiBsYLSJiTsyBybVuN8= +github.com/google/go-cmp v0.7.0/go.mod h1:pXiqmnSA92OHEEa9HXL2W4E7lf9JzCmGVUdgjX3N/iU= +github.com/hexops/gotextdiff v1.0.3 h1:gitA9+qJrrTCsiCl7+kh75nPqQt1cx4ZkudSTLoUqJM= +github.com/hexops/gotextdiff v1.0.3/go.mod h1:pSWU5MAI3yDq+fZBTazCSJysOMbxWL1BSow5/V2vxeg= +github.com/klauspost/compress v1.18.0 h1:c/Cqfb0r+Yi+JtIEq73FWXVkRonBlf0CRNYc8Zttxdo= +github.com/klauspost/compress v1.18.0/go.mod h1:2Pp+KzxcywXVXMr50+X0Q/Lsb43OQHYWRCY2AiWywWQ= +github.com/kr/pretty v0.3.1 h1:flRD4NNwYAUpkphVc1HcthR4KEIFJ65n8Mw5qdRn3LE= +github.com/kr/pretty v0.3.1/go.mod h1:hoEshYVHaxMs3cyo3Yncou5ZscifuDolrwPKZanG3xk= +github.com/kr/text v0.2.0 h1:5Nx0Ya0ZqY2ygV366QzturHI13Jq95ApcVaJBhpS+AY= +github.com/kr/text v0.2.0/go.mod h1:eLer722TekiGuMkidMxC/pM04lWEeraHUUmBw8l2grE= +github.com/kylelemons/godebug v1.1.0 h1:RPNrshWIDI6G2gRW9EHilWtl7Z6Sb1BR0xunSBf0SNc= +github.com/kylelemons/godebug v1.1.0/go.mod h1:9/0rRGxNHcop5bhtWyNeEfOS8JIWk580+fNqagV/RAw= +github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 h1:C3w9PqII01/Oq1c1nUAm88MOHcQC9l5mIlSMApZMrHA= +github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822/go.mod h1:+n7T8mK8HuQTcFwEeznm/DIxMOiR9yIdICNftLE1DvQ= +github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM= +github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4= +github.com/prometheus/client_golang v1.23.2 h1:Je96obch5RDVy3FDMndoUsjAhG5Edi49h0RJWRi/o0o= +github.com/prometheus/client_golang v1.23.2/go.mod h1:Tb1a6LWHB3/SPIzCoaDXI4I8UHKeFTEQ1YCr+0Gyqmg= +github.com/prometheus/client_model v0.6.2 h1:oBsgwpGs7iVziMvrGhE53c/GrLUsZdHnqNwqPLxwZyk= +github.com/prometheus/client_model v0.6.2/go.mod h1:y3m2F6Gdpfy6Ut/GBsUqTWZqCUvMVzSfMLjcu6wAwpE= +github.com/prometheus/common v0.66.1 h1:h5E0h5/Y8niHc5DlaLlWLArTQI7tMrsfQjHV+d9ZoGs= +github.com/prometheus/common v0.66.1/go.mod h1:gcaUsgf3KfRSwHY4dIMXLPV0K/Wg1oZ8+SbZk/HH/dA= +github.com/prometheus/procfs v0.16.1 h1:hZ15bTNuirocR6u0JZ6BAHHmwS1p8B4P6MRqxtzMyRg= +github.com/prometheus/procfs v0.16.1/go.mod h1:teAbpZRB1iIAJYREa1LsoWUXykVXA1KlTmWl8x/U+Is= +github.com/rogpeppe/go-internal v1.10.0 h1:TMyTOH3F/DB16zRVcYyreMH6GnZZrwQVAoYjRBZyWFQ= +github.com/rogpeppe/go-internal v1.10.0/go.mod h1:UQnix2H7Ngw/k4C5ijL5+65zddjncjaFoBhdsK/akog= +github.com/stretchr/testify v1.11.1 h1:7s2iGBzp5EwR7/aIZr8ao5+dra3wiQyKjjFuvgVKu7U= +github.com/stretchr/testify v1.11.1/go.mod h1:wZwfW3scLgRK+23gO65QZefKpKQRnfz6sD981Nm4B6U= +go.uber.org/goleak v1.3.0 h1:2K3zAYmnTNqV73imy9J1T3WC+gmCePx2hEGkimedGto= +go.uber.org/goleak v1.3.0/go.mod h1:CoHD4mav9JJNrW/WLlf7HGZPjdw8EucARQHekz1X6bE= +go.yaml.in/yaml/v2 v2.4.2 h1:DzmwEr2rDGHl7lsFgAHxmNz/1NlQ7xLIrlN2h5d1eGI= +go.yaml.in/yaml/v2 v2.4.2/go.mod h1:081UH+NErpNdqlCXm3TtEran0rJZGxAYx9hb/ELlsPU= +golang.org/x/sys v0.35.0 h1:vz1N37gP5bs89s7He8XuIYXpyY0+QlsKmzipCbUtyxI= +golang.org/x/sys v0.35.0/go.mod h1:BJP2sWEmIv4KK5OTEluFJCKSidICx8ciO85XgH3Ak8k= +google.golang.org/protobuf v1.36.8 h1:xHScyCOEuuwZEc6UtSOvPbAT4zRh0xcNRYekJwfqyMc= +google.golang.org/protobuf v1.36.8/go.mod h1:fuxRtAxBytpl4zzqUh6/eyUujkJdNiuEkXntxiD/uRU= +gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0= +gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c h1:Hei/4ADfdWqJk1ZMxUNpqntNwaWcugrBjAiHlqqRiVk= +gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c/go.mod h1:JHkPIbrfpd72SG/EVd6muEfDQjcINNoR0C8j2r3qZ4Q= +gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA= +gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM= diff --git a/hashes.nix b/hashes.nix new file mode 100644 index 0000000..4b7d66b --- /dev/null +++ b/hashes.nix @@ -0,0 +1,3 @@ +{ + vendor = "sha256-IO+MeOuwXcbKbLUkXFv6aJYfymbCd9kZXOyLMPAARLE="; +} diff --git a/main.go b/main.go new file mode 100644 index 0000000..919fe24 --- /dev/null +++ b/main.go @@ -0,0 +1,149 @@ +package main + +import ( + "bufio" + "bytes" + "encoding/json" + "fmt" + "log/slog" + "maps" + "net/http" + "os" + "os/exec" + "regexp" + "slices" + "strings" + "time" + + "github.com/alecthomas/kong" + "github.com/prometheus/client_golang/prometheus" + "github.com/prometheus/client_golang/prometheus/promhttp" +) + +type Args struct { + Port int `help:"Port to listen on" short:"p" default:"8888" env:"PORT"` + Repos StringMap `placeholder:"{\"name\": \"path\", ...}" required:"" help:"Repositories to be grepped" env:"REPOS"` + Patterns StringMap `placeholder:"{\"name\": \"regex\", ...}" required:"" help:"Patterns to be grepped for" env:"PATTERNS"` + Interval time.Duration `help:"How often the repos should be grepped (units: s,m,h for seconds, minutes, hours)" default:"10m" env:"INTERVAL"` +} + +type StringMap map[string]string + +func (p *StringMap) UnmarshalJSON(data []byte) error { + stringMap := (*map[string]string)(p) + return json.Unmarshal(data, &stringMap) +} + +func main() { + logger := slog.New(slog.NewTextHandler(os.Stderr, &slog.HandlerOptions{ + Level: slog.LevelDebug, + })) + slog.SetDefault(logger) + + var args Args + ctx := kong.Parse(&args, kong.Description( + "Prometheus metrics for how many lines in certain git repos match certain regular expressions.\n\n"+ + "Only the HEAD of the repositories will be grepped.", + )) + + http.Handle("/metrics", promhttp.Handler()) + + te, err := newGitGrepExporter(args.Repos, args.Patterns, prometheus.DefaultRegisterer) + ctx.FatalIfErrorf(err) + + go func() { + ticker := time.NewTicker(args.Interval) + defer ticker.Stop() + + // execute immediately on start + te.grepRepos() + + for range ticker.C { + te.grepRepos() + } + }() + + slog.Info("starting", "repos", args.Repos, "patterns", args.Patterns, "interval", args.Interval) + slog.Info(fmt.Sprintf("serving metrics at http://localhost:%d/metrics", args.Port)) + http.ListenAndServe(fmt.Sprintf(":%d", args.Port), nil) +} + +type GitGrepExporter struct { + repos map[string]string + gauges map[string]*prometheus.GaugeVec + regexes map[string]*regexp.Regexp + combinedPattern string +} + +func newGitGrepExporter(repos map[string]string, patterns map[string]string, reg prometheus.Registerer) (*GitGrepExporter, error) { + if len(repos) == 0 { + return nil, fmt.Errorf("no repositories specified") + } + if len(patterns) == 0 { + return nil, fmt.Errorf("no patterns specified") + } + + gauges := map[string]*prometheus.GaugeVec{} + regexes := map[string]*regexp.Regexp{} + + for name, pattern := range patterns { + gauges[name] = prometheus.NewGaugeVec(prometheus.GaugeOpts{ + Name: fmt.Sprintf("%s_lines", name), + }, []string{"repo"}) + reg.MustRegister(gauges[name]) + regexes[name] = regexp.MustCompile(pattern) + } + + return &GitGrepExporter{repos, gauges, regexes, strings.Join(slices.Collect(maps.Values(patterns)), "|")}, nil +} + +func (g *GitGrepExporter) grepRepos() { + for name, path := range g.repos { + slog.Info("starting grep", "path", path) + g.grepRepo(name) + slog.Info("finished grep", "path", path) + } +} + +func (g *GitGrepExporter) grepRepo(name string) { + path := g.repos[name] + output, err := run("git", "-C", path, "grep", "-hE", g.combinedPattern, "HEAD") + + if err != nil { + if exitErr, ok := err.(*exec.ExitError); ok { + if exitErr.ExitCode() == 1 { + // no matches found + + for _, gauge := range g.gauges { + gauge.With(map[string]string{"repo": name}).Set(0) + } + return + } + + slog.Error("git grep failed", "stderr", string(output)) + return + } + + slog.Error("failed to execute git grep", "error", err) + return + } + + scanner := bufio.NewScanner(bytes.NewReader(output)) + counts := map[string]float64{} + for scanner.Scan() { + line := scanner.Text() + for word, regex := range g.regexes { + if regex.FindString(line) != "" { + counts[word] += 1 + } + } + } + for word, gauge := range g.gauges { + gauge.With(map[string]string{"repo": name}).Set(counts[word]) + } +} + +var run = func(name string, args ...string) ([]byte, error) { + cmd := exec.Command(name, args...) + return cmd.CombinedOutput() +} diff --git a/main_test.go b/main_test.go new file mode 100644 index 0000000..bd5130a --- /dev/null +++ b/main_test.go @@ -0,0 +1,63 @@ +package main + +import ( + "log" + "strings" + "testing" + + "github.com/google/go-cmp/cmp" + "github.com/prometheus/client_golang/prometheus" + "github.com/prometheus/common/expfmt" +) + +func TestGrepRepo(t *testing.T) { + repos := map[string]string{"project1": "/srv/repos/project1"} + patterns := map[string]string{"match": "\\bMATCH\\b", "match_start": "^MATCH"} + reg := prometheus.NewRegistry() + te, err := newGitGrepExporter(repos, patterns, reg) + if err != nil { + t.Fatal(err) + } + + run = func(name string, args ...string) ([]byte, error) { + return []byte( + "not a match\n" + + "MATCH can be at the start\n" + + "here MATCH is in the middle\n" + + "the end can also be MATCH\n" + + "MATCH, MATCH counts only once\n", + ), nil + } + + te.grepRepo("project1") + + want := "# HELP match_lines \n" + + "# TYPE match_lines gauge\n" + + "match_lines{repo=\"project1\"} 4\n" + + "# HELP match_start_lines \n" + + "# TYPE match_start_lines gauge\n" + + "match_start_lines{repo=\"project1\"} 2\n" + + if diff := cmp.Diff(collectMetrics(reg), want); diff != "" { + t.Errorf("unexpected metrics: %v", diff) + } +} + +func collectMetrics(reg *prometheus.Registry) string { + mfs, done, err := prometheus.ToTransactionalGatherer(reg).Gather() + if err != nil { + log.Fatal(err) + } + defer done() + + var buf strings.Builder + enc := expfmt.NewEncoder(&buf, expfmt.NewFormat(expfmt.TypeTextPlain)) + + for _, mf := range mfs { + err := enc.Encode(mf) + if err != nil { + log.Fatal(err) + } + } + return buf.String() +} diff --git a/service.nix b/service.nix new file mode 100644 index 0000000..0b5aa91 --- /dev/null +++ b/service.nix @@ -0,0 +1,51 @@ +{ config, lib, pkgs, ... }: + +let + git_grep_exporter = pkgs.callPackage ./default.nix {}; + cfg = config.services.gitGrepExporter; +in +{ + options.services.gitGrepExporter = { + enable = lib.mkEnableOption "git-grep-exporter"; + + port = lib.mkOption { + type = lib.types.int; + }; + + patterns = lib.mkOption { + type = lib.types.attrsOf lib.types.str; + }; + + repos = lib.mkOption { + type = lib.types.attrsOf lib.types.str; + }; + + extraGroups = lib.mkOption { + type = lib.types.listOf lib.types.str; + default = []; + }; + + interval = lib.mkOption { + type = lib.types.nullOr lib.types.str; + default = "10m"; + }; + }; + + config = lib.mkIf cfg.enable { + systemd.services.git-grep-exporter = { + serviceConfig = { + DynamicUser = true; + SupplementaryGroups = cfg.extraGroups; + ExecStart = "${git_grep_exporter}/bin/git-grep-exporter"; + }; + environment = { + PORT = toString cfg.port; + REPOS = builtins.toJSON cfg.repos; + PATTERNS = builtins.toJSON cfg.patterns; + INTERVAL = cfg.interval; + }; + + wantedBy = ["multi-user.target"]; + }; + }; +} -- cgit v1.3.1