feat(job): support templ command

cmd/relspec/job.go

@@ -16,7 +16,9 @@ import (
 	"git.warky.dev/wdevs/relspecgo/pkg/models"
 	"git.warky.dev/wdevs/relspecgo/pkg/readers"
 	"git.warky.dev/wdevs/relspecgo/pkg/readers/sqldir"
+	"git.warky.dev/wdevs/relspecgo/pkg/writers"
 	wpgsql "git.warky.dev/wdevs/relspecgo/pkg/writers/pgsql"
+	wtemplate "git.warky.dev/wdevs/relspecgo/pkg/writers/template"
 )
 
 var (
@@ -54,7 +56,7 @@ inputs, output and options:
       logfile: .relspec/log/build-schema.log
 
 Rules and guarantees:
-  - command is a closed allow-list (convert, merge, scripts-list). Arbitrary
+  - command is a closed allow-list (convert, merge, scripts-list, templ). Arbitrary
     shell strings are never executed.
   - Every path is relative to the directory holding the job file and may not
     escape it. Absolute and home-relative paths are rejected.
@@ -215,6 +217,7 @@ type resolvedJob struct {
 	outputConn    string // resolved connection string (secret)
 	outputConnEnv string
 	logPath       string
+	templatePath  string
 	secrets       []string // resolved secret values to redact from logs
 }
 
@@ -236,6 +239,17 @@ func preflightJob(j *jobs.Job) (*resolvedJob, error) {
 		}
 		rj.logPath = p
 	}
+	if j.Template != "" {
+		p, err := jobs.SafeJoin(root, j.Template)
+		if err != nil {
+			return nil, fmt.Errorf("template: %w", err)
+		}
+		info, err := os.Stat(p)
+		if err != nil || info.IsDir() {
+			return nil, fmt.Errorf("template %q: not found or is a directory", j.Template)
+		}
+		rj.templatePath = p
+	}
 
 	for i, in := range j.Inputs {
 		ri := resolvedInput{format: strings.ToLower(in.Format)}
@@ -348,6 +362,8 @@ func executeResolvedJob(rj *resolvedJob) (err error) {
 		err = runMergeJob(rj, lg)
 	case jobs.CommandScriptsList:
 		err = runScriptsListJob(rj, lg)
+	case jobs.CommandTempl:
+		err = runTemplJob(rj, lg)
 	default:
 		err = fmt.Errorf("unsupported command %q", rj.job.Command)
 	}
@@ -359,6 +375,50 @@ func executeResolvedJob(rj *resolvedJob) (err error) {
 	return err
 }
 
+func runTemplJob(rj *resolvedJob, lg *jobLogger) error {
+	db, err := readJobInputs(rj, lg)
+	if err != nil {
+		return err
+	}
+	if schema := rj.job.Options.Schema; schema != "" {
+		found := false
+		for _, s := range db.Schemas {
+			if s.Name == schema {
+				db.Schemas = []*models.Schema{s}
+				found = true
+				break
+			}
+		}
+		if !found {
+			return fmt.Errorf("schema not found: %s", schema)
+		}
+	}
+	mode := rj.job.Mode
+	if mode == "" {
+		mode = "database"
+	}
+	pattern := rj.job.FilenamePattern
+	if pattern == "" {
+		pattern = "{{.Name}}.txt"
+	}
+	writer, err := wtemplate.NewWriter(&writers.WriterOptions{
+		OutputPath: rj.outputPath,
+		Metadata: map[string]interface{}{
+			"template_path":    rj.templatePath,
+			"mode":             mode,
+			"filename_pattern": pattern,
+		},
+	})
+	if err != nil {
+		return fmt.Errorf("create template writer: %w", err)
+	}
+	lg.logf("applying template: %s (mode %s)", rj.templatePath, mode)
+	if err := writer.WriteDatabase(db); err != nil {
+		return fmt.Errorf("execute template: %w", err)
+	}
+	return nil
+}
+
 func runConvertJob(rj *resolvedJob, lg *jobLogger) error {
 	db, err := readJobInputs(rj, lg)
 	if err != nil {

cmd/relspec/job_test.go

@@ -375,3 +375,30 @@ jobs:
 		t.Fatal("job list output not deterministic")
 	}
 }
+
+func TestJobRun_TemplDatabaseMode(t *testing.T) {
+	dir := jobFixture(t, `version: 1
+jobs:
+  docs:
+    command: templ
+    inputs:
+      - path: schema/core.dbml
+        format: dbml
+    template: templates/schema.tmpl
+    output:
+      path: build/schema.txt
+      overwrite: true
+`)
+	writeFile(t, filepath.Join(dir, "templates", "schema.tmpl"), "{{range .Database.Schemas}}{{range .Tables}}{{.Name}} {{end}}{{end}}")
+	set := mustLoadSet(t, filepath.Join(dir, "relspec.yml"))
+	if err := executeJobPlan(set, "docs", false, false, &bytes.Buffer{}); err != nil {
+		t.Fatalf("execute templ job: %v", err)
+	}
+	out, err := os.ReadFile(filepath.Join(dir, "build", "schema.txt"))
+	if err != nil {
+		t.Fatalf("read templ output: %v", err)
+	}
+	if !strings.Contains(string(out), "users") {
+		t.Fatalf("templ output missing users table: %s", out)
+	}
+}

docs/JOB_FILES.md

@@ -25,9 +25,10 @@ means adding a vetted adapter in the RelSpec source.
 | `convert`      | read one or more input schemas, additively merge them, write one output |
 | `merge`        | like `convert` but requires ≥2 inputs and exposes `skip_*` merge options |
 | `scripts-list` | deterministically list SQL scripts across one or more directories   |
+| `templ`        | apply a custom Go text template to one or more input schemas          |
 
 Deferred (documented, not implemented here): `scripts` execution against a live
-database, `split`, `inspect`, `diff`, `templ`, job-to-job output wiring,
+database, `split`, `inspect`, `diff`, job-to-job output wiring,
 log rotation/retention. Live SQL execution already exists as
 `relspec scripts execute`; wiring it into the job runner is a follow-up because
 it needs live database credentials and cannot be covered by offline tests.
@@ -123,6 +124,9 @@ jobs:
     script_dirs:                               # scripts-list (≥1)
       - migrations/core
       - migrations/tenant
+    template: templates/schema.tmpl             # templ (required)
+    mode: table                                 # templ: database/schema/script/table
+    filename_pattern: "{{.Name}}.go"           # templ multi-output modes
     output:                                    # convert / merge (required)
       format: pgsql
       path: build/schema.sql                   # file output, OR:
@@ -141,6 +145,11 @@ jobs:
     logfile: .relspec/log/<job-name>.log       # optional; appended to
 ```
 
+For `templ`, `inputs` use the same file or `pgsql`/`conn_env` source forms as
+schema conversion. `output` is optional (empty means stdout); when present it
+contains only `path` and `overwrite`, because templates do not select a schema
+writer format.
+
 ### Supported input formats
 
 `dbml`, `dctx`, `drawdb`, `graphql`, `json`, `yaml`, `gorm`, `bun`, `drizzle`,

pkg/jobs/jobs.go

@@ -33,10 +33,11 @@ const (
 	CommandConvert     = "convert"      // read one or more schema files, optionally merge, write one output
 	CommandMerge       = "merge"        // additive merge of two or more schema files into one output
 	CommandScriptsList = "scripts-list" // deterministically list SQL scripts across one or more directories
+	CommandTempl       = "templ"        // apply a custom Go text template to one or more schemas
 )
 
 // SupportedCommands lists every accepted command, in help order.
-var SupportedCommands = []string{CommandConvert, CommandMerge, CommandScriptsList}
+var SupportedCommands = []string{CommandConvert, CommandMerge, CommandScriptsList, CommandTempl}
 
 // readerFormats are the file-based input formats a job may declare (path).
 var readerFormats = map[string]bool{
@@ -77,6 +78,9 @@ type Job struct {
 	DependsOn       []string `yaml:"depends_on"`
 	Inputs          []Input  `yaml:"inputs"`
 	ScriptDirs      []string `yaml:"script_dirs"`
+	Template        string   `yaml:"template"`
+	Mode            string   `yaml:"mode"`
+	FilenamePattern string   `yaml:"filename_pattern"`
 	Output          *Output  `yaml:"output"`
 	Options         Options  `yaml:"options"`
 	Logfile         string   `yaml:"logfile"`
@@ -258,7 +262,7 @@ func (j *Job) validate() []string {
 	var e []string
 
 	switch j.Command {
-	case CommandConvert, CommandMerge, CommandScriptsList:
+	case CommandConvert, CommandMerge, CommandScriptsList, CommandTempl:
 	case "":
 		e = append(e, "missing command")
 		return e
@@ -277,6 +281,7 @@ func (j *Job) validate() []string {
 		}
 	}
 	checkPath("logfile", j.Logfile)
+	checkPath("template", j.Template)
 	for _, in := range j.Inputs {
 		checkPath("input path", in.Path)
 	}
@@ -317,6 +322,63 @@ func (j *Job) validate() []string {
 		if j.Output != nil {
 			e = append(e, "output is not valid for command \"scripts-list\"")
 		}
+	case CommandTempl:
+		if len(j.Inputs) < 1 {
+			e = append(e, "command \"templ\" requires at least 1 input")
+		}
+		for i, in := range j.Inputs {
+			e = append(e, validateTemplInput(i, in)...)
+		}
+		if j.Template == "" {
+			e = append(e, "command \"templ\" requires template")
+		}
+		mode := strings.ToLower(j.Mode)
+		if mode == "" {
+			mode = "database"
+		}
+		switch mode {
+		case "database", "schema", "script", "table":
+		default:
+			e = append(e, fmt.Sprintf("command \"templ\" has unsupported mode %q (supported: database, schema, script, table)", j.Mode))
+		}
+		if len(j.ScriptDirs) > 0 {
+			e = append(e, "script_dirs is not valid for command \"templ\"")
+		}
+		if j.Output != nil && j.Output.ConnEnv != "" {
+			e = append(e, "command \"templ\" does not support database output")
+		}
+		if j.Output != nil && j.Output.Format != "" {
+			e = append(e, "output.format is not valid for command \"templ\"")
+		}
+	}
+	return e
+}
+
+func validateTemplInput(i int, in Input) []string {
+	var e []string
+	if in.Format == "" {
+		return []string{fmt.Sprintf("input[%d]: missing format", i)}
+	}
+	f := strings.ToLower(in.Format)
+	if f == "pgsql" {
+		if in.ConnEnv == "" {
+			e = append(e, fmt.Sprintf("input[%d]: format %q requires conn_env (an environment variable name)", i, in.Format))
+		}
+		if in.Path != "" {
+			e = append(e, fmt.Sprintf("input[%d]: format %q takes conn_env, not path", i, in.Format))
+		}
+	} else if readerFormats[f] {
+		if in.Path == "" {
+			e = append(e, fmt.Sprintf("input[%d]: missing path", i))
+		}
+		if in.ConnEnv != "" {
+			e = append(e, fmt.Sprintf("input[%d]: format %q does not use conn_env", i, in.Format))
+		}
+	} else {
+		e = append(e, fmt.Sprintf("input[%d]: unsupported templ input format %q", i, in.Format))
+	}
+	if looksLikeSecret(in.ConnEnv) {
+		e = append(e, fmt.Sprintf("input[%d]: conn_env must be an environment variable name, not a connection string", i))
 	}
 	return e
 }