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// Package search reads one index, filtered by read access inside the query. Chapter 17.
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package search
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import (
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"context"
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"strings"
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"github.com/barerepo/server/internal/store"
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// Kind orders the set: code first, because a barerepo is usually searched for a symbol.
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type Kind int
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const (
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Code Kind = iota
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Thread
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Repo
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func (k Kind) String() string {
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switch k {
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case Code:
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return "code"
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case Thread:
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return "thread"
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default:
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return "repo"
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// Result is one row of one set, so every row names the repository it came from.
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type Result struct {
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Kind Kind
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Owner string
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Name string
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Path string // code: the file. thread: the number.
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Line int
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Text string // the matching line, or the thread title
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Context string
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Href string
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// Finder is the index query, an interface so the page depends on the question and not the schema.
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type Finder interface {
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FindDocs(ctx context.Context, viewer, query string, limit int) ([]store.Doc, error)
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// Search asks the index once. The read filter is inside that query, never applied to the answer.
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func Search(ctx context.Context, db Finder, viewer, query string, limit int) []Result {
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query = strings.TrimSpace(query)
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if query == "" || limit <= 0 || db == nil {
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return nil
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docs, err := db.FindDocs(ctx, viewer, query, limit)
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if err != nil {
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return nil
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out := make([]Result, 0, len(docs))
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for _, d := range docs {
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if len(out) >= limit {
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break
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owner, name, ok := strings.Cut(d.Repo, "/")
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if !ok {
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continue
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switch d.Kind {
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case store.Code:
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for _, m := range matches(d.Body, query, linesPerFile) {
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out = append(out, Result{Kind: Code, Owner: owner, Name: name, Path: d.Path,
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Line: m.n, Text: m.text,
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Href: "/" + d.Repo + "/file/" + defaultRef + "/" + d.Path})
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case store.Thread:
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line, _ := match(d.Body, query)
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out = append(out, Result{Kind: Thread, Owner: owner, Name: name, Path: d.Path,
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Text: d.Title, Context: line,
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Href: "/" + d.Repo + "/thread/" + d.Path})
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default:
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out = append(out, Result{Kind: Repo, Owner: owner, Name: name,
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Text: d.Title, Context: d.Body, Href: "/" + d.Repo})
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return out
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// defaultRef is what a file link resolves through, because HEAD is the branch this index was built from.
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const defaultRef = "HEAD"
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// linesPerFile bounds one file's share of a result set, so a common word cannot fill the page.
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const linesPerFile = 3
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// hit is one matching line and the number it sits on.
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type hit struct {
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text string
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n int
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// matches finds where the query is, so a reader sees the occurrences and not only the first.
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func matches(body, query string, limit int) []hit {
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want := strings.ToLower(query)
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lines := strings.Split(body, "\n")
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var out []hit
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for i, line := range lines {
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if !strings.Contains(strings.ToLower(line), want) {
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continue
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}
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out = append(out, hit{strings.TrimRight(line, "\r"), i + 1})
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if len(out) == limit {
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break
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}
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}
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return out
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// match is one line, for a thread, where the excerpt is context rather than a result of its own.
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func match(body, query string) (string, int) {
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if m := matches(body, query, 1); len(m) == 1 {
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return m[0].text, m[0].n
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}
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return "", 0