get cid from url

automod/engine/account_meta.go

···
 
 type ProfileSummary struct {
 	HasAvatar   bool
-	Avatar      *string
+	AvatarCid   *string
+	BannerCid   *string
 	Description *string
 	DisplayName *string
 }

automod/engine/cid_from_cdn_test.go

···
+package engine
+
+import (
+	"github.com/stretchr/testify/assert"
+	"testing"
+)
+
+func TestCidFromCdnUrl(t *testing.T) {
+	assert := assert.New(t)
+
+	fixCid := "abcdefghijk"
+
+	fixtures := []struct {
+		url string
+		cid *string
+	}{
+		{
+			url: "https://cdn.bsky.app/img/avatar/plain/did:plc:abc123/abcdefghijk@jpeg",
+			cid: &fixCid,
+		},
+		{
+			url: "https://cdn.bsky.app/img/feed_fullsize/plain/did:plc:abc123/abcdefghijk@jpeg",
+			cid: &fixCid,
+		},
+		{
+			url: "https://cdn.bsky.app/img/feed_fullsize",
+			cid: nil,
+		},
+		{
+			url: "https://cdn.bsky.app/img/feed_fullsize/plain/did:plc:abc123/abcdefghijk",
+			cid: &fixCid,
+		},
+		{
+			url: "https://cdn.asky.app/img/feed_fullsize/plain/did:plc:abc123/abcdefghijk@jpeg",
+			cid: nil,
+		},
+	}
+
+	for _, fix := range fixtures {
+		assert.Equal(fix.cid, CidFromCdnUrl(&fix.url))
+	}
+}

automod/engine/fetch_account_meta.go

···
 	"encoding/json"
 	"errors"
 	"fmt"
+	"net/url"
+	"strings"
 	"time"
 
 	comatproto "github.com/bluesky-social/indigo/api/atproto"
···
 )
 
 var newAccountRetryDuration = 3 * 1000 * time.Millisecond
+
+// get the cid from a bluesky cdn url
+func CidFromCdnUrl(str *string) *string {
+	if str == nil {
+		return nil
+	}
+
+	u, err := url.Parse(*str)
+	if err != nil || u.Host != "cdn.bsky.app" {
+		return nil
+	}
+
+	parts := strings.Split(u.Path, "/")
+	if len(parts) != 6 {
+		return nil
+	}
+
+	return &strings.Split(parts[5], "@")[0]
+}
 
 // Helper to hydrate metadata about an account from several sources: PDS (if access), mod service (if access), public identity resolution
 func (e *Engine) GetAccountMeta(ctx context.Context, ident *identity.Identity) (*AccountMeta, error) {
···
 
 	am.Profile = ProfileSummary{
 		HasAvatar:   pv.Avatar != nil,
-		Avatar:      pv.Avatar,
+		AvatarCid:   cidFromCdnUrl(pv.Avatar),
+		BannerCid:   cidFromCdnUrl(pv.Banner),
 		Description: pv.Description,
 		DisplayName: pv.DisplayName,
 	}

automod/engine/util.go

···
 package engine
 
+import (
+	"net/url"
+	"strings"
+)
+
 func dedupeStrings(in []string) []string {
 	var out []string
 	seen := make(map[string]bool)
···
 	}
 	return out
 }
+
+// get the cid from a bluesky cdn url
+func cidFromCdnUrl(str *string) *string {
+	if str == nil {
+		return nil
+	}
+
+	u, err := url.Parse(*str)
+	if err != nil || u.Host != "cdn.bsky.app" {
+		return nil
+	}
+
+	parts := strings.Split(u.Path, "/")
+	if len(parts) != 6 {
+		return nil
+	}
+
+	return &strings.Split(parts[5], "@")[0]
+}