Support `pager` and `no-pager` config options

adapter/sqlite/note_dao.go

@@ -147,85 +147,7 @@ func (d *NoteDAO) exists(path string) (bool, error) {
 }
 
 func (d *NoteDAO) Find(opts note.FinderOpts, callback func(note.Match) error) (int, error) {
-	rows, err := func() (*sql.Rows, error) {
-		snippetCol := `""`
-		whereExprs := make([]string, 0)
-		orderTerms := make([]string, 0)
-		args := make([]interface{}, 0)
-
-		for _, filter := range opts.Filters {
-			switch filter := filter.(type) {
-
-			case note.MatchFilter:
-				snippetCol = `snippet(notes_fts, 2, '<zk:match>', '</zk:match>', '…', 20) as snippet`
-				orderTerms = append(orderTerms, `bm25(notes_fts, 1000.0, 500.0, 1.0)`)
-				whereExprs = append(whereExprs, "notes_fts MATCH ?")
-				args = append(args, fts5.ConvertQuery(string(filter)))
-
-			case note.PathFilter:
-				if len(filter) == 0 {
-					break
-				}
-				globs := make([]string, 0)
-				for _, path := range filter {
-					globs = append(globs, "n.path GLOB ?")
-					args = append(args, path+"*")
-				}
-				whereExprs = append(whereExprs, strings.Join(globs, " OR "))
-
-			case note.ExcludePathFilter:
-				if len(filter) == 0 {
-					break
-				}
-				globs := make([]string, 0)
-				for _, path := range filter {
-					globs = append(globs, "n.path NOT GLOB ?")
-					args = append(args, path+"*")
-				}
-				whereExprs = append(whereExprs, strings.Join(globs, " AND "))
-
-			case note.DateFilter:
-				value := "?"
-				field := "n." + dateField(filter)
-				op, ignoreTime := dateDirection(filter)
-				if ignoreTime {
-					field = "date(" + field + ")"
-					value = "date(?)"
-				}
-
-				whereExprs = append(whereExprs, fmt.Sprintf("%s %s %s", field, op, value))
-				args = append(args, filter.Date)
-
-			default:
-				panic(fmt.Sprintf("%v: unknown filter type", filter))
-			}
-		}
-
-		for _, sorter := range opts.Sorters {
-			orderTerms = append(orderTerms, orderTerm(sorter))
-		}
-		orderTerms = append(orderTerms, `n.title ASC`)
-
-		query := "SELECT n.id, n.path, n.title, n.body, n.word_count, n.created, n.modified, n.checksum, " + snippetCol
-
-		query += `
-FROM notes n
-JOIN notes_fts
-ON n.id = notes_fts.rowid`
-
-		if len(whereExprs) > 0 {
-			query += "\nWHERE " + strings.Join(whereExprs, "\nAND ")
-		}
-
-		query += "\nORDER BY " + strings.Join(orderTerms, ", ")
-
-		if opts.Limit > 0 {
-			query += fmt.Sprintf("\nLIMIT %d", opts.Limit)
-		}
-
-		return d.tx.Query(query, args...)
-	}()
-
+	rows, err := d.findRows(opts)
 	if err != nil {
 		return 0, err
 	}
@@ -265,6 +187,94 @@ ON n.id = notes_fts.rowid`
 	return count, nil
 }
 
+type findQuery struct {
+	SnippetCol string
+	WhereExprs []string
+	OrderTerms []string
+	Args       []interface{}
+}
+
+func (d *NoteDAO) findRows(opts note.FinderOpts) (*sql.Rows, error) {
+	snippetCol := `""`
+	whereExprs := make([]string, 0)
+	orderTerms := make([]string, 0)
+	args := make([]interface{}, 0)
+
+	for _, filter := range opts.Filters {
+		switch filter := filter.(type) {
+
+		case note.MatchFilter:
+			snippetCol = `snippet(notes_fts, 2, '<zk:match>', '</zk:match>', '…', 20) as snippet`
+			orderTerms = append(orderTerms, `bm25(notes_fts, 1000.0, 500.0, 1.0)`)
+			whereExprs = append(whereExprs, "notes_fts MATCH ?")
+			args = append(args, fts5.ConvertQuery(string(filter)))
+
+		case note.PathFilter:
+			if len(filter) == 0 {
+				break
+			}
+			globs := make([]string, 0)
+			for _, path := range filter {
+				globs = append(globs, "n.path GLOB ?")
+				args = append(args, path+"*")
+			}
+			whereExprs = append(whereExprs, strings.Join(globs, " OR "))
+
+		case note.ExcludePathFilter:
+			if len(filter) == 0 {
+				break
+			}
+			globs := make([]string, 0)
+			for _, path := range filter {
+				globs = append(globs, "n.path NOT GLOB ?")
+				args = append(args, path+"*")
+			}
+			whereExprs = append(whereExprs, strings.Join(globs, " AND "))
+
+		case note.DateFilter:
+			value := "?"
+			field := "n." + dateField(filter)
+			op, ignoreTime := dateDirection(filter)
+			if ignoreTime {
+				field = "date(" + field + ")"
+				value = "date(?)"
+			}
+
+			whereExprs = append(whereExprs, fmt.Sprintf("%s %s %s", field, op, value))
+			args = append(args, filter.Date)
+
+		default:
+			panic(fmt.Sprintf("%v: unknown filter type", filter))
+		}
+	}
+
+	for _, sorter := range opts.Sorters {
+		orderTerms = append(orderTerms, orderTerm(sorter))
+	}
+	orderTerms = append(orderTerms, `n.title ASC`)
+
+	query := "SELECT n.id, n.path, n.title, n.body, n.word_count, n.created, n.modified, n.checksum, " + snippetCol
+
+	query += `
+FROM notes n
+JOIN notes_fts
+ON n.id = notes_fts.rowid`
+
+	if len(whereExprs) > 0 {
+		query += "\nWHERE " + strings.Join(whereExprs, "\nAND ")
+	}
+
+	query += "\nORDER BY " + strings.Join(orderTerms, ", ")
+
+	if opts.Limit > 0 {
+		query += fmt.Sprintf("\nLIMIT %d", opts.Limit)
+	}
+
+	// fmt.Println(query)
+	// fmt.Println(args)
+	return d.tx.Query(query, args...)
+}
+
 func dateField(filter note.DateFilter) string {
 	switch filter.Field {
 	case note.DateCreated:

cmd/container.go

@@ -1,11 +1,15 @@
 package cmd
 
 import (
+	"io"
+
 	"github.com/mickael-menu/zk/adapter/handlebars"
 	"github.com/mickael-menu/zk/adapter/sqlite"
 	"github.com/mickael-menu/zk/adapter/tty"
+	"github.com/mickael-menu/zk/core/zk"
 	"github.com/mickael-menu/zk/util"
 	"github.com/mickael-menu/zk/util/date"
+	"github.com/mickael-menu/zk/util/pager"
 )
 
 type Container struct {
@@ -43,3 +47,25 @@ func (c *Container) Database(path string) (*sqlite.DB, error) {
 	err = db.Migrate()
 	return db, err
 }
+
+// Paginate creates an auto-closing io.Writer which will be automatically
+// paginated if noPager is false, using the user's pager.
+//
+// You can write to the pager only in the run callback.
+func (c *Container) Paginate(noPager bool, config zk.Config, run func(out io.Writer) error) error {
+	pager, err := c.pager(noPager || config.NoPager, config)
+	if err != nil {
+		return err
+	}
+	err = run(pager)
+	pager.Close()
+	return err
+}
+
+func (c *Container) pager(noPager bool, config zk.Config) (*pager.Pager, error) {
+	if noPager {
+		return pager.PassthroughPager, nil
+	} else {
+		return pager.New(config.Pager, c.Logger)
+	}
+}

cmd/list.go

@@ -2,6 +2,7 @@ package cmd
 
 import (
 	"fmt"
+	"io"
 	"time"
 
 	"github.com/mickael-menu/zk/adapter/sqlite"
@@ -9,7 +10,6 @@ import (
 	"github.com/mickael-menu/zk/core/zk"
 	"github.com/mickael-menu/zk/util/errors"
 	"github.com/mickael-menu/zk/util/opt"
-	"github.com/mickael-menu/zk/util/pager"
 	"github.com/mickael-menu/zk/util/strings"
 	"github.com/tj/go-naturaldate"
 )
@@ -58,17 +58,11 @@ func (cmd *List) Run(container *Container) error {
 			Templates: container.TemplateLoader(zk.Config.Lang),
 		}
 
-		p := pager.PassthroughPager
-		if !cmd.NoPager {
-			p, err = pager.New(logger)
-			if err != nil {
-				return err
-			}
-		}
-
-		count, err := note.List(*opts, deps, p.WriteString)
-
-		p.Close()
+		count := 0
+		err = container.Paginate(cmd.NoPager, zk.Config, func(out io.Writer) error {
+			count, err = note.List(*opts, deps, out)
+			return err
+		})
 
 		if err == nil {
 			fmt.Printf("\nFound %d %s\n", count, strings.Pluralize("result", count))

core/note/list.go

@@ -1,6 +1,8 @@
 package note
 
 import (
+	"fmt"
+	"io"
 	"os"
 	"path/filepath"
 	"regexp"
@@ -24,7 +26,7 @@ type ListDeps struct {
 
 // List finds notes matching given criteria and formats them according to user
 // preference.
-func List(opts ListOpts, deps ListDeps, callback func(formattedNote string) error) (int, error) {
+func List(opts ListOpts, deps ListDeps, out io.Writer) (int, error) {
 	templ := matchTemplate(opts.Format)
 	template, err := deps.Templates.Load(templ)
 	if err != nil {
@@ -40,7 +42,9 @@ func List(opts ListOpts, deps ListDeps, callback func(formattedNote string) erro
 		if err != nil {
 			return err
 		}
-		return callback(res)
+
+		_, err = fmt.Fprintln(out, res)
+		return err
 	})
 }
 

core/zk/config.go

@@ -11,8 +11,10 @@ import (
 // Config holds the global user configuration.
 type Config struct {
 	DirConfig
-	Dirs   map[string]DirConfig
-	Editor opt.String
+	Dirs    map[string]DirConfig
+	Editor  opt.String
+	Pager   opt.String
+	NoPager bool
 }
 
 // DirConfig holds the user configuration for a given directory.
@@ -115,6 +117,8 @@ func ParseConfig(content []byte, templatesDir string) (*Config, error) {
 		DirConfig: root,
 		Dirs:      make(map[string]DirConfig),
 		Editor:    opt.NewNotEmptyString(hcl.Editor),
+		Pager:     opt.NewNotEmptyString(hcl.Pager),
+		NoPager:   hcl.NoPager,
 	}
 
 	for _, dirHCL := range hcl.Dirs {
@@ -183,6 +187,8 @@ type hclConfig struct {
 	Extra        map[string]string `hcl:"extra,optional"`
 	Dirs         []hclDirConfig    `hcl:"dir,block"`
 	Editor       string            `hcl:"editor,optional"`
+	Pager        string            `hcl:"pager,optional"`
+	NoPager      bool              `hcl:"no-pager,optional"`
 }
 
 type hclDirConfig struct {

core/zk/config_test.go

@@ -5,8 +5,8 @@ import (
 	"testing"
 
 	"github.com/google/go-cmp/cmp"
-	"github.com/mickael-menu/zk/util/test/assert"
 	"github.com/mickael-menu/zk/util/opt"
+	"github.com/mickael-menu/zk/util/test/assert"
 )
 
 func TestParseDefaultConfig(t *testing.T) {
@@ -43,6 +43,8 @@ func TestParseComplete(t *testing.T) {
 	conf, err := ParseConfig([]byte(`
 		// Comment
 		editor = "vim"
+		pager = "less"
+		no-pager = true
 		filename = "{{id}}.note"
 		extension = "txt"
 		template = "default.note"
@@ -130,7 +132,9 @@ func TestParseComplete(t *testing.T) {
 				},
 			},
 		},
-		Editor: opt.NewString("vim"),
+		Editor:  opt.NewString("vim"),
+		Pager:   opt.NewString("less"),
+		NoPager: true,
 	})
 }
 

util/opt/opt.go

@@ -56,7 +56,8 @@ func (s String) Unwrap() string {
 }
 
 func (s String) Equal(other String) bool {
-	return s.value == other.value || *s.value == *other.value
+	return s.value == other.value ||
+		(s.value != nil && other.value != nil && *s.value == *other.value)
 }
 
 func (s String) String() string {

util/pager/pager.go

@@ -31,10 +31,10 @@ var PassthroughPager = &Pager{
 }
 
 // New creates a pager.Pager to be used to write a paginated text to the TTY.
-func New(logger util.Logger) (*Pager, error) {
+func New(pagerCmd opt.String, logger util.Logger) (*Pager, error) {
 	wrap := errors.Wrapper("failed to paginate the output, try again with --no-pager or fix your PAGER environment variable")
 
-	pagerCmd := locatePager()
+	pagerCmd = selectPagerCmd(pagerCmd)
 	if pagerCmd.IsNull() {
 		return PassthroughPager, nil
 	}
@@ -98,17 +98,24 @@ func (p *Pager) WriteString(text string) error {
 	return err
 }
 
-func locatePager() opt.String {
+// selectPagerCmd returns the paging command meant to be run.
+//
+// By order of precedence: ZK_PAGER, config.pager, PAGER then the default
+// pagers.
+func selectPagerCmd(userPager opt.String) opt.String {
 	return osutil.GetOptEnv("ZK_PAGER").
+		Or(userPager).
 		Or(osutil.GetOptEnv("PAGER")).
-		Or(locateDefaultPager())
+		Or(selectDefaultPager())
 }
 
 var defaultPagers = []string{
 	"less -FIRX", "more -R",
 }
 
-func locateDefaultPager() opt.String {
+// selectDefaultPager returns the first pager in the list of defaultPagers
+// available on the execution paths.
+func selectDefaultPager() opt.String {
 	for _, pager := range defaultPagers {
 		parts, err := shellquote.Split(pager)
 		if err != nil {