Minor optimization to not derive schema when using existing schema (#140)

Author: rayokota

schemaregistry/serde/avro.ts

@@ -71,12 +71,19 @@ export class AvroSerializer extends Serializer implements AvroSerde {
       throw new Error('message is empty')
     }
 
-    let avroSchema = AvroSerializer.messageToSchema(msg)
-    const schema: SchemaInfo = {
-      schemaType: 'AVRO',
-      schema: JSON.stringify(avroSchema),
+    let schema: SchemaInfo | undefined = undefined
+    // Don't derive the schema if it is being looked up in the following ways
+    if (this.config().useSchemaId == null &&
+        !this.config().useLatestVersion &&
+        this.config().useLatestWithMetadata == null) {
+      const avroSchema = AvroSerializer.messageToSchema(msg)
+      schema = {
+        schemaType: 'AVRO',
+        schema: JSON.stringify(avroSchema),
+      }
     }
     const [id, info] = await this.getId(topic, msg, schema)
+    let avroSchema: avro.Type
     let deps: Map<string, string>
     [avroSchema, deps] = await this.toType(info)
     const subject = this.subjectName(topic, info)

schemaregistry/serde/json.ts

@@ -91,10 +91,16 @@ export class JsonSerializer extends Serializer implements JsonSerde {
       throw new Error('message is empty')
     }
 
-    const jsonSchema = JsonSerializer.messageToSchema(msg)
-    const schema: SchemaInfo = {
-      schemaType: 'JSON',
-      schema: JSON.stringify(jsonSchema),
+    let schema: SchemaInfo | undefined = undefined
+    // Don't derive the schema if it is being looked up in the following ways
+    if (this.config().useSchemaId == null &&
+      !this.config().useLatestVersion &&
+      this.config().useLatestWithMetadata == null) {
+      const jsonSchema = JsonSerializer.messageToSchema(msg)
+      schema = {
+        schemaType: 'JSON',
+        schema: JSON.stringify(jsonSchema),
+      }
     }
     const [id, info] = await this.getId(topic, msg, schema)
     const subject = this.subjectName(topic, info)

schemaregistry/serde/protobuf.ts

@@ -149,8 +149,15 @@ export class ProtobufSerializer extends Serializer implements ProtobufSerde {
     if (messageDesc == null) {
       throw new SerializationError('message descriptor not in registry')
     }
-    const fileDesc = messageDesc.file
-    const schema = await this.getSchemaInfo(fileDesc)
+
+    let schema: SchemaInfo | undefined = undefined
+    // Don't derive the schema if it is being looked up in the following ways
+    if (this.config().useSchemaId == null &&
+      !this.config().useLatestVersion &&
+      this.config().useLatestWithMetadata == null) {
+      const fileDesc = messageDesc.file
+      schema = await this.getSchemaInfo(fileDesc)
+    }
     const [id, info] = await this.getId(topic, msg, schema, 'serialized')
     const subject = this.subjectName(topic, info)
     msg = await this.executeRules(subject, topic, RuleMode.WRITE, null, info, msg, null)

schemaregistry/serde/serde.ts

@@ -244,7 +244,7 @@ export abstract class Serializer extends Serde {
   abstract serialize(topic: string, msg: any): Promise<Buffer>
 
   // GetID returns a schema ID for the given schema
-  async getId(topic: string, msg: any, info: SchemaInfo, format?: string): Promise<[number, SchemaInfo]> {
+  async getId(topic: string, msg: any, info?: SchemaInfo, format?: string): Promise<[number, SchemaInfo]> {
     let autoRegister = this.config().autoRegisterSchemas
     let useSchemaId = this.config().useSchemaId
     let useLatestWithMetadata = this.conf.useLatestWithMetadata
@@ -254,7 +254,7 @@ export abstract class Serializer extends Serde {
     let id = -1
     let subject = this.subjectName(topic, info)
     if (autoRegister) {
-      id = await this.client.register(subject, info, Boolean(normalizeSchema))
+      id = await this.client.register(subject, info!, Boolean(normalizeSchema))
     } else if (useSchemaId != null && useSchemaId >= 0) {
       info = await this.client.getBySubjectAndId(subject, useSchemaId, format)
       id = useSchemaId
@@ -267,9 +267,9 @@ export abstract class Serializer extends Serde {
       info = metadata
       id = metadata.id
     } else {
-      id = await this.client.getId(subject, info, Boolean(normalizeSchema))
+      id = await this.client.getId(subject, info!, Boolean(normalizeSchema))
     }
-    return [id, info]
+    return [id, info!]
   }
 
   writeBytes(id: number, msgBytes: Buffer): Buffer {