feat(nodejs): protocol version option, binary protocol for doubles

src/buffer/bufferv1.ts

@@ -0,0 +1,26 @@
+// @ts-check
+import { SenderOptions } from "../options";
+import { SenderBuffer } from "./index";
+import { SenderBufferBase } from "./base";
+
+class SenderBufferV1 extends SenderBufferBase {
+  constructor(options: SenderOptions) {
+    super(options);
+  }
+
+  floatColumn(name: string, value: number): SenderBuffer {
+    this.writeColumn(
+      name,
+      value,
+      () => {
+        const valueStr = value.toString();
+        this.checkCapacity([valueStr]);
+        this.write(valueStr);
+      },
+      "number",
+    );
+    return this;
+  }
+}
+
+export { SenderBufferV1 };

src/buffer/bufferv2.ts

@@ -0,0 +1,30 @@
+// @ts-check
+import { SenderOptions } from "../options";
+import { SenderBuffer } from "./index";
+import { SenderBufferBase } from "./base";
+
+const ENTITY_TYPE_DOUBLE: number = 16;
+const EQUALS_SIGN: number = "=".charCodeAt(0);
+
+class SenderBufferV2 extends SenderBufferBase {
+  constructor(options: SenderOptions) {
+    super(options);
+  }
+
+  floatColumn(name: string, value: number): SenderBuffer {
+    this.writeColumn(
+      name,
+      value,
+      () => {
+        this.checkCapacity([], 10);
+        this.writeByte(EQUALS_SIGN);
+        this.writeByte(ENTITY_TYPE_DOUBLE);
+        this.writeDouble(value);
+      },
+      "number",
+    );
+    return this;
+  }
+}
+
+export { SenderBufferV2 };