add missing config.go file

cache/config.go

@@ -0,0 +1,106 @@
+package cache
+
+import (
+	"encoding/json"
+	"io/ioutil"
+	"log"
+	"os"
+)
+
+type CacheOptions struct {
+	CacheSizeM           int
+	MaxOpenFiles         int
+	BlockRestartInterval int
+	WriteBufferSizeM     int
+	BlockSizeK           int
+}
+
+type CoordsCacheOptions struct {
+	CacheOptions
+	BunchSize int
+}
+type OSMCacheOptions struct {
+	Coords       CoordsCacheOptions
+	Ways         CacheOptions
+	Nodes        CacheOptions
+	Relations    CacheOptions
+	InsertedWays CacheOptions
+	CoordsIndex  CacheOptions
+	WaysIndex    CacheOptions
+}
+
+const defaultConfig = `
+{
+    "Coords": {
+        "CacheSizeM": 16,
+        "WriteBufferSizeM": 64,
+        "BlockSizeK": 0,
+        "MaxOpenFiles": 64,
+        "BlockRestartInterval": 256,
+        "BunchSize": 32
+    },
+    "Nodes": {
+        "CacheSizeM": 16,
+        "WriteBufferSizeM": 64,
+        "BlockSizeK": 0,
+        "MaxOpenFiles": 64,
+        "BlockRestartInterval": 128
+    },
+    "Ways": {
+        "CacheSizeM": 16,
+        "WriteBufferSizeM": 64,
+        "BlockSizeK": 0,
+        "MaxOpenFiles": 64,
+        "BlockRestartInterval": 128
+    },
+    "Relations": {
+        "CacheSizeM": 16,
+        "WriteBufferSizeM": 64,
+        "BlockSizeK": 0,
+        "MaxOpenFiles": 64,
+        "BlockRestartInterval": 128
+    },
+    "InsertedWays": {
+        "CacheSizeM": 0,
+        "WriteBufferSizeM": 0,
+        "BlockSizeK": 0,
+        "MaxOpenFiles": 0,
+        "BlockRestartInterval": 0
+    },
+    "CoordsIndex": {
+        "CacheSizeM": 32,
+        "WriteBufferSizeM": 128,
+        "BlockSizeK": 0,
+        "MaxOpenFiles": 256,
+        "BlockRestartInterval": 256
+    },
+    "WaysIndex": {
+        "CacheSizeM": 16,
+        "WriteBufferSizeM": 64,
+        "BlockSizeK": 0,
+        "MaxOpenFiles": 64,
+        "BlockRestartInterval": 128
+    }
+}
+`
+
+var osmCacheOptions OSMCacheOptions
+
+func init() {
+	err := json.Unmarshal([]byte(defaultConfig), &osmCacheOptions)
+	if err != nil {
+		panic(err)
+	}
+
+	cacheConfFile := os.Getenv("GOPOSM_CACHE_CONFIG")
+	if cacheConfFile != "" {
+		data, err := ioutil.ReadFile(cacheConfFile)
+		if err != nil {
+			log.Println("Unable to read cache config:", err)
+		}
+		err = json.Unmarshal(data, &osmCacheOptions)
+		if err != nil {
+			log.Println("Unable to parse cache config:", err)
+		}
+	}
+}