more on merge support

2 files changed, 118 insertions, 21 deletions

diff --git a/internal/server/handle/handle.go b/internal/server/handle/handle.go
index 011e31c..0a0a1bb 100644
--- a/internal/server/handle/handle.go
+++ b/internal/server/handle/handle.go
@@ -1,12 +1,13 @@
 package handle
 
 import (
+	"errors"
 	"fmt"
 	"io"
-	"log"
 	"net/http"
 	"os"
 	"regexp"
+	"strings"
 	"time"
 
 	"codeberg.org/snonux/gos/internal"
@@ -51,7 +52,7 @@ func List(w http.ResponseWriter, r *http.Request, dataDir string) error {
 		return fmt.Errorf("expexted GET request")
 	}
 
-	list, err := repository.New(dataDir).List()
+	list, err := repository.Instance(dataDir).List()
 	if err != nil {
 		return err
 	}
@@ -61,12 +62,12 @@ func List(w http.ResponseWriter, r *http.Request, dataDir string) error {
 }
 
 func Get(w http.ResponseWriter, r *http.Request, dataDir string) error {
-	path := r.URL.Query().Get("path")
-	if !getIDRe.MatchString(path) {
-		return fmt.Errorf("invalid path %s", path)
+	id := r.URL.Query().Get("id")
+	if !getIDRe.MatchString(id) {
+		return fmt.Errorf("invalid id %s", id)
 	}
 
-	data, err := os.ReadFile(fmt.Sprintf("%s/%s", dataDir, path))
+	data, err := os.ReadFile(fmt.Sprintf("%s/%s", dataDir, id))
 	if err != err {
 		return err
 	}
@@ -76,11 +77,75 @@ func Get(w http.ResponseWriter, r *http.Request, dataDir string) error {
 }
 
 func Merge(w http.ResponseWriter, r *http.Request, conf server.ServerConfig) error {
+	var errs []error
+
 	for _, partner := range conf.Partners() {
-		uri := fmt.Sprintf("%s/list", partner)
-		data, err := easyhttp.Get(uri, conf.ApiKey)
-		log.Println(string(data), err)
+		if err := mergeFromPartner(conf, partner); err != nil {
+			errs = append(errs, err)
+		}
+	}
+
+	err := combineErrors(errs)
+	if err != nil {
+		fmt.Fprint(w, err.Error())
+		return err
 	}
 
+	fmt.Fprint(w, "Okiedokie")
 	return nil
 }
+
+func mergeFromPartner(conf server.ServerConfig, partner string) error {
+	var (
+		errs  []error
+		uri   = fmt.Sprintf("%s/list", partner)
+		repo  = repository.Instance(conf.DataDir)
+		pairs []repository.EntryPair
+	)
+
+	if err := easyhttp.GetData(uri, conf.ApiKey, &pairs); err != nil {
+		return err
+	}
+
+	for _, pair := range pairs {
+		if repo.HasEntry(pair) {
+			continue
+		}
+
+		var (
+			entry types.Entry
+			uri   = fmt.Sprintf("%s/get?id=%s", partner, pair.ID)
+		)
+
+		if err := easyhttp.GetData(uri, conf.ApiKey, &entry); err != nil {
+			errs = append(errs, err)
+			continue
+		}
+
+		// In theory, this should never happen
+		if pair.ID != entry.ID {
+			errs = append(errs, fmt.Errorf("pair ID %s does not match entry id %s", pair.ID, entry.ID))
+			continue
+		}
+
+		repo.Merge(entry)
+	}
+
+	return combineErrors(errs)
+}
+
+func combineErrors(errs []error) error {
+	if len(errs) == 0 {
+		return nil
+	}
+
+	var sb strings.Builder
+	for i, err := range errs {
+		if i > 0 {
+			sb.WriteString("; ")
+		}
+		sb.WriteString(err.Error())
+	}
+
+	return errors.New(sb.String())
+}
diff --git a/internal/server/repository/repository.go b/internal/server/repository/repository.go
index 7eb7122..4146526 100644
--- a/internal/server/repository/repository.go
+++ b/internal/server/repository/repository.go
@@ -11,23 +11,35 @@ import (
 	"codeberg.org/snonux/gos/internal/types"
 )
 
+var (
+	instance Repository
+	once     sync.Once
+)
+
+// Contains an Entry ID and its checksumm, for the list and merge operations.
+type EntryPair struct {
+	ID, Checksum string
+}
+
 type Repository struct {
 	dataDir string
 	entries map[string]types.Entry
 	mu      *sync.Mutex
 }
 
-func New(dataDir string) Repository {
-	return Repository{
-		dataDir: dataDir,
-		entries: make(map[string]types.Entry),
-		mu:      &sync.Mutex{},
-	}
+func Instance(dataDir string) Repository {
+	once.Do(func() {
+		instance.dataDir = dataDir
+		instance.entries = make(map[string]types.Entry)
+		instance.mu = &sync.Mutex{}
+	})
+	return instance
 }
 
 func (r Repository) store(entry types.Entry) {
 	r.mu.Lock()
 	defer r.mu.Unlock()
+
 	r.entries[entry.ID] = entry
 }
 
@@ -60,17 +72,37 @@ func (r Repository) List() ([]byte, error) {
 		return []byte{}, err
 	}
 
-	type pair struct {
-		ID, Checksum string
-	}
-
-	var pairs []pair
+	var pairs []EntryPair
 	r.mu.Lock()
 	defer r.mu.Unlock()
 
 	for _, entry := range r.entries {
-		pairs = append(pairs, pair{entry.ID, entry.Checksum()})
+		pairs = append(pairs, EntryPair{entry.ID, entry.Checksum()})
 	}
 
 	return json.Marshal(pairs)
 }
+
+func (r Repository) HasEntry(pair EntryPair) bool {
+	r.mu.Lock()
+	defer r.mu.Unlock()
+
+	ent, ok := r.entries[pair.ID]
+	if !ok || ent.Checksum() != pair.Checksum {
+		return false
+	}
+	return true
+}
+
+func (r Repository) Merge(new types.Entry) {
+	r.mu.Lock()
+	defer r.mu.Unlock()
+
+	old, ok := r.entries[new.ID]
+	if !ok {
+		r.entries[new.ID] = new
+		return
+	}
+
+	r.entries[new.ID] = old.Update(new)
+}