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implement DraftStore

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This commit is contained in:
Brian Picciano 2022-08-18 22:25:17 -06:00
parent 76ff79f470
commit 7ac2f5ebb3
4 changed files with 372 additions and 56 deletions
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186
srv/src/post/draft_post.go Normal file
View File

@ -0,0 +1,186 @@
package post
import (
"database/sql"
"encoding/json"
"errors"
"fmt"
)
type DraftStore interface {
// Set sets the draft Post's data into the storage, keyed by the draft
// Post's ID.
Set(post Post) error
// Get returns count draft Posts, sorted id descending, offset by the
// given page number. The returned boolean indicates if there are more pages
// or not.
Get(page, count int) ([]Post, bool, error)
// GetByID will return the draft Post with the given ID, or ErrPostNotFound.
GetByID(id string) (Post, error)
// Delete will delete the draft Post with the given ID.
Delete(id string) error
}
type draftStore struct {
db *SQLDB
}
// NewDraftStore initializes a new DraftStore using an existing SQLDB.
func NewDraftStore(db *SQLDB) DraftStore {
return &draftStore{
db: db,
}
}
func (s *draftStore) Set(post Post) error {
if post.ID == "" {
return errors.New("post ID can't be empty")
}
tagsJSON, err := json.Marshal(post.Tags)
if err != nil {
return fmt.Errorf("json marshaling tags %#v: %w", post.Tags, err)
}
_, err = s.db.db.Exec(
`INSERT INTO post_drafts (
id, title, description, tags, series, body
)
VALUES
(?, ?, ?, ?, ?, ?)
ON CONFLICT (id) DO UPDATE SET
title=excluded.title,
description=excluded.description,
tags=excluded.tags,
series=excluded.series,
body=excluded.body`,
post.ID,
post.Title,
post.Description,
&sql.NullString{String: string(tagsJSON), Valid: len(post.Tags) > 0},
&sql.NullString{String: post.Series, Valid: post.Series != ""},
post.Body,
)
if err != nil {
return fmt.Errorf("inserting into post_drafts: %w", err)
}
return nil
}
func (s *draftStore) get(
querier interface {
Query(string, ...interface{}) (*sql.Rows, error)
},
limit, offset int,
where string, whereArgs ...interface{},
) (
[]Post, error,
) {
query := `
SELECT
p.id, p.title, p.description, p.tags, p.series, p.body
FROM post_drafts p
ORDER BY p.id ASC`
if limit > 0 {
query += fmt.Sprintf(" LIMIT %d", limit)
}
if offset > 0 {
query += fmt.Sprintf(" OFFSET %d", offset)
}
rows, err := querier.Query(query, whereArgs...)
if err != nil {
return nil, fmt.Errorf("selecting: %w", err)
}
defer rows.Close()
var posts []Post
for rows.Next() {
var (
post Post
tags, series sql.NullString
)
err := rows.Scan(
&post.ID, &post.Title, &post.Description, &tags, &series,
&post.Body,
)
if err != nil {
return nil, fmt.Errorf("scanning row: %w", err)
}
post.Series = series.String
if tags.String != "" {
if err := json.Unmarshal([]byte(tags.String), &post.Tags); err != nil {
return nil, fmt.Errorf("json parsing %q: %w", tags.String, err)
}
}
posts = append(posts, post)
}
return posts, nil
}
func (s *draftStore) Get(page, count int) ([]Post, bool, error) {
posts, err := s.get(s.db.db, count+1, page*count, ``)
if err != nil {
return nil, false, fmt.Errorf("querying post_drafts: %w", err)
}
var hasMore bool
if len(posts) > count {
hasMore = true
posts = posts[:count]
}
return posts, hasMore, nil
}
func (s *draftStore) GetByID(id string) (Post, error) {
posts, err := s.get(s.db.db, 0, 0, `WHERE p.id=?`, id)
if err != nil {
return Post{}, fmt.Errorf("querying post_drafts: %w", err)
}
if len(posts) == 0 {
return Post{}, ErrPostNotFound
}
if len(posts) > 1 {
panic(fmt.Sprintf("got back multiple draft posts querying id %q: %+v", id, posts))
}
return posts[0], nil
}
func (s *draftStore) Delete(id string) error {
if _, err := s.db.db.Exec(`DELETE FROM post_drafts WHERE id = ?`, id); err != nil {
return fmt.Errorf("deleting from post_drafts: %w", err)
}
return nil
}

130
srv/src/post/draft_post_test.go Normal file
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@ -0,0 +1,130 @@
package post
import (
"sort"
"testing"
"github.com/stretchr/testify/assert"
)
type draftStoreTestHarness struct {
store DraftStore
}
func newDraftStoreTestHarness(t *testing.T) draftStoreTestHarness {
db := NewInMemSQLDB()
t.Cleanup(func() { db.Close() })
store := NewDraftStore(db)
return draftStoreTestHarness{
store: store,
}
}
func TestDraftStore(t *testing.T) {
assertPostEqual := func(t *testing.T, exp, got Post) {
t.Helper()
sort.Strings(exp.Tags)
sort.Strings(got.Tags)
assert.Equal(t, exp, got)
}
assertPostsEqual := func(t *testing.T, exp, got []Post) {
t.Helper()
if !assert.Len(t, got, len(exp), "exp:%+v\ngot: %+v", exp, got) {
return
}
for i := range exp {
assertPostEqual(t, exp[i], got[i])
}
}
t.Run("not_found", func(t *testing.T) {
h := newDraftStoreTestHarness(t)
_, err := h.store.GetByID("foo")
assert.ErrorIs(t, err, ErrPostNotFound)
})
t.Run("set_get_delete", func(t *testing.T) {
h := newDraftStoreTestHarness(t)
post := testPost(0)
post.Tags = []string{"foo", "bar"}
err := h.store.Set(post)
assert.NoError(t, err)
gotPost, err := h.store.GetByID(post.ID)
assert.NoError(t, err)
assertPostEqual(t, post, gotPost)
// we will now try updating the post, and ensure it updates properly
post.Title = "something else"
post.Series = "whatever"
post.Body = "anything"
post.Tags = []string{"bar", "baz"}
err = h.store.Set(post)
assert.NoError(t, err)
gotPost, err = h.store.GetByID(post.ID)
assert.NoError(t, err)
assertPostEqual(t, post, gotPost)
// delete the post, it should go away
assert.NoError(t, h.store.Delete(post.ID))
_, err = h.store.GetByID(post.ID)
assert.ErrorIs(t, err, ErrPostNotFound)
})
t.Run("get", func(t *testing.T) {
h := newDraftStoreTestHarness(t)
posts := []Post{
testPost(0),
testPost(1),
testPost(2),
testPost(3),
}
for _, post := range posts {
err := h.store.Set(post)
assert.NoError(t, err)
}
gotPosts, hasMore, err := h.store.Get(0, 2)
assert.NoError(t, err)
assert.True(t, hasMore)
assertPostsEqual(t, posts[:2], gotPosts)
gotPosts, hasMore, err = h.store.Get(1, 2)
assert.NoError(t, err)
assert.False(t, hasMore)
assertPostsEqual(t, posts[2:4], gotPosts)
posts = append(posts, testPost(4))
err = h.store.Set(posts[4])
assert.NoError(t, err)
gotPosts, hasMore, err = h.store.Get(1, 2)
assert.NoError(t, err)
assert.True(t, hasMore)
assertPostsEqual(t, posts[2:4], gotPosts)
gotPosts, hasMore, err = h.store.Get(2, 2)
assert.NoError(t, err)
assert.False(t, hasMore)
assertPostsEqual(t, posts[4:], gotPosts)
})
}

55
srv/src/post/post.go
View File

@ -77,44 +77,16 @@ type Store interface {
}
type store struct {
db *sql.DB
db *SQLDB
}
// NewStore initializes a new Store using an existing SQLDB.
func NewStore(db *SQLDB) Store {
return &store{
db: db.db,
db: db,
}
}
// if the callback returns an error then the transaction is aborted.
func (s *store) withTx(cb func(*sql.Tx) error) error {
tx, err := s.db.Begin()
if err != nil {
return fmt.Errorf("starting transaction: %w", err)
}
if err := cb(tx); err != nil {
if rollbackErr := tx.Rollback(); rollbackErr != nil {
return fmt.Errorf(
"rolling back transaction: %w (original error: %v)",
rollbackErr, err,
)
}
return fmt.Errorf("performing transaction: %w (rolled back)", err)
}
if err := tx.Commit(); err != nil {
return fmt.Errorf("committing transaction: %w", err)
}
return nil
}
func (s *store) Set(post Post, now time.Time) (bool, error) {
if post.ID == "" {
@ -123,7 +95,7 @@ func (s *store) Set(post Post, now time.Time) (bool, error) {
var first bool
err := s.withTx(func(tx *sql.Tx) error {
err := s.db.withTx(func(tx *sql.Tx) error {
nowTS := now.Unix()
@ -270,7 +242,7 @@ func (s *store) get(
func (s *store) Get(page, count int) ([]StoredPost, bool, error) {
posts, err := s.get(s.db, count+1, page*count, ``)
posts, err := s.get(s.db.db, count+1, page*count, ``)
if err != nil {
return nil, false, fmt.Errorf("querying posts: %w", err)
@ -288,7 +260,7 @@ func (s *store) Get(page, count int) ([]StoredPost, bool, error) {
func (s *store) GetByID(id string) (StoredPost, error) {
posts, err := s.get(s.db, 0, 0, `WHERE p.id=?`, id)
posts, err := s.get(s.db.db, 0, 0, `WHERE p.id=?`, id)
if err != nil {
return StoredPost{}, fmt.Errorf("querying posts: %w", err)
@ -306,14 +278,14 @@ func (s *store) GetByID(id string) (StoredPost, error) {
}
func (s *store) GetBySeries(series string) ([]StoredPost, error) {
return s.get(s.db, 0, 0, `WHERE p.series=?`, series)
return s.get(s.db.db, 0, 0, `WHERE p.series=?`, series)
}
func (s *store) GetByTag(tag string) ([]StoredPost, error) {
var posts []StoredPost
err := s.withTx(func(tx *sql.Tx) error {
err := s.db.withTx(func(tx *sql.Tx) error {
rows, err := tx.Query(`SELECT post_id FROM post_tags WHERE tag = ?`, tag)
@ -357,7 +329,7 @@ func (s *store) GetByTag(tag string) ([]StoredPost, error) {
func (s *store) GetTags() ([]string, error) {
rows, err := s.db.Query(`SELECT tag FROM post_tags GROUP BY tag`)
rows, err := s.db.db.Query(`SELECT tag FROM post_tags GROUP BY tag`)
if err != nil {
return nil, fmt.Errorf("querying all tags: %w", err)
}
@ -381,11 +353,7 @@ func (s *store) GetTags() ([]string, error) {
func (s *store) Delete(id string) error {
tx, err := s.db.Begin()
if err != nil {
return fmt.Errorf("starting transaction: %w", err)
}
return s.db.withTx(func(tx *sql.Tx) error {
if _, err := tx.Exec(`DELETE FROM post_tags WHERE post_id = ?`, id); err != nil {
return fmt.Errorf("deleting from post_tags: %w", err)
@ -395,9 +363,6 @@ func (s *store) Delete(id string) error {
return fmt.Errorf("deleting from posts: %w", err)
}
if err := tx.Commit(); err != nil {
return fmt.Errorf("committing transaction: %w", err)
}
return nil
})
}

43
srv/src/post/sql.go
View File

@ -38,10 +38,18 @@ var migrations = &migrate.MemoryMigrationSource{Migrations: []*migrate.Migration
body BLOB NOT NULL
)`,
},
Down: []string{
"DROP TABLE assets",
"DROP TABLE post_tags",
"DROP TABLE posts",
},
{
Id: "2",
Up: []string{
`CREATE TABLE post_drafts (
id TEXT NOT NULL PRIMARY KEY,
title TEXT NOT NULL,
description TEXT NOT NULL,
tags TEXT,
series TEXT,
body TEXT NOT NULL
)`,
},
},
}}
@ -89,3 +97,30 @@ func NewInMemSQLDB() *SQLDB {
func (db *SQLDB) Close() error {
return db.db.Close()
}
func (db *SQLDB) withTx(cb func(*sql.Tx) error) error {
tx, err := db.db.Begin()
if err != nil {
return fmt.Errorf("starting transaction: %w", err)
}
if err := cb(tx); err != nil {
if rollbackErr := tx.Rollback(); rollbackErr != nil {
return fmt.Errorf(
"rolling back transaction: %w (original error: %v)",
rollbackErr, err,
)
}
return fmt.Errorf("performing transaction: %w (rolled back)", err)
}
if err := tx.Commit(); err != nil {
return fmt.Errorf("committing transaction: %w", err)
}
return nil
}