Relaxing Context type for better DX (#71)

example-project/index.js

@@ -19,14 +19,14 @@ const logger = new Logtail(process.argv[2], { sendLogsToConsoleOutput: true });
 // Usage
 
 // Send debug level log using the debug() method
-logger.debug("I am using Logtail!");
+const debugLog = logger.debug("I am using Logtail!");
 
 // Send info level log using the info() method
-logger.info("An interesting event occured!")
+const infoLog = logger.info("An interesting event occured!");
 
 // Send warn level log using the warn() method
 // You can add additional structured data to help you troubleshoot your code as shown below
-logger.warn("Something is not quite right, better check on it.",{
+const warningLog = logger.warn("Something is not quite right, better check on it.",{
     user:{
         username:"someuser",
         email:"[email protected]"
@@ -36,9 +36,20 @@ logger.warn("Something is not quite right, better check on it.",{
     }
 });
 
-// Send error level log using the error() method
-logger.error("Oops! An runtime ERROR occurred!").then(
-    // Logging methods are async function returning Promises
+function callbackThatMightFail() {
+    throw new Error("Testing error")
+}
+
+let errorLog;
+try {
+    callbackThatMightFail();
+} catch (err) {
+    // Send error level log using the error() method
+    errorLog = logger.error("Oops! An runtime ERROR occurred!", err);
+}
+
+// Logging methods are async function returning Promises
+Promise.all([debugLog, infoLog, warningLog, errorLog]).then(
     // OnResolve write message
     function() {
         console.log("All done! You can check your logs now.")

packages/bunyan/src/bunyan.test.ts

@@ -1,6 +1,6 @@
 import bunyan, { LogLevelString } from "bunyan";
 import { Logtail } from "@logtail/node";
-import {Context, LogLevel} from "@logtail/types";
+import { LogLevel } from "@logtail/types";
 
 import { LogtailStream } from "./bunyan";
 
@@ -130,9 +130,8 @@ describe("Bunyan tests", () => {
   it("should include correct context fields", async done => {
     const logtail = new Logtail("test");
     logtail.setSync(async logs => {
-      const context = logs[0].context as Context;
-      const runtime = context.runtime as Context;
-      expect(runtime.file).toMatch("bunyan.test.ts")
+      const context = logs[0].context;
+      expect(context.runtime.file).toMatch("bunyan.test.ts")
       done();
       return logs;
     });

packages/core/src/base.test.ts

@@ -257,7 +257,7 @@ describe("base class tests", () => {
     expect(log.message).toBe(message);
 
     // Context should contain a stack trace
-    expect((log as any).stack).toBe(e.stack);
+    expect(log.stack).toBe(e.stack);
   });
 
   it("should not ignore exceptions if `ignoreExceptions` opt == false and `throwExceptions` opt == true", async () => {

packages/node/src/node.ts

@@ -66,6 +66,10 @@ export class Node extends Base {
       const wrappedContext: unknown = { extra: context };
       context = wrappedContext as TContext;
     }
+    if (context instanceof Error) {
+      const wrappedContext: unknown = { error: context };
+      context = wrappedContext as TContext;
+    }
 
     // Process/sync the log, per `Base` logic
     context = { ...getStackContext(this, stackContextHint), ...context };
@@ -108,6 +112,12 @@ export class Node extends Base {
       }
 
       return value.toISOString();
+    } else if (value instanceof Error) {
+      return {
+        name: value.name,
+        message: value.message,
+        stack: value.stack?.split("\n"),
+      };
     } else if ((typeof value === "object" || Array.isArray(value)) && (maxDepth < 1 || visitedObjects.has(value))) {
       if (visitedObjects.has(value)) {
         if (this._options.contextObjectCircularRefWarn) {
@@ -143,8 +153,10 @@ export class Node extends Base {
       visitedObjects.delete(value);
 
       return logClone;
-    } else {
+    } else if (typeof value === 'undefined') {
       return undefined;
+    } else {
+      return `<omitted unserializable ${typeof value}>`;
     }
   }
 }

packages/types/README.md

@@ -131,10 +131,10 @@ We call this 'context' and these are the types:
 
 ```typescript
 /**
- * Context type - a string/number/bool/Date, or a nested object of the same
+ * Context type - a nested object of serializable types (a string / number / bool / null / undefined / Array / Date / Error)
  */
-export type ContextKey = string | number | boolean | Date;
-export type Context = { [key: string]: ContextKey | Context };
+export type ContextKey = any;
+export type Context = { [key: string]: ContextKey  };
 ```
 
 ### `ILogtailLog`
@@ -146,7 +146,7 @@ interface ILogtailLog {
   dt: Date;
   level: LogLevel; // <-- see `LogLevel` above
   message: string;
-  [key: string]: ContextKey | Context; // <-- see `Context` above
+  [key: string]: ContextKey; // <-- see `Context` above
 }
 ```
 

packages/types/src/types.ts

@@ -98,10 +98,10 @@ export enum LogLevel {
 }
 
 /**
- * Context type - a string/number/bool/Date, or a nested object of the same
+ * Context type - a nested object of serializable types (a string / number / bool / null / undefined / Array / Date / Error)
  */
-export type ContextKey = string | number | boolean | Date | null;
-export type Context = { [key: string]: ContextKey | Context };
+export type ContextKey = any;
+export type Context = { [key: string]: ContextKey };
 export type StackContextHint = { fileName: string, methodNames: [string] };
 
 /**
@@ -111,7 +111,7 @@ export interface ILogtailLog {
   dt: Date;
   level: ILogLevel;
   message: string;
-  [key: string]: ContextKey | Context;
+  [key: string]: ContextKey;
 }
 
 /**

packages/winston/src/winston.test.ts

@@ -211,8 +211,7 @@ describe("Winston logging tests", () => {
 
     const logs = await logged;
 
-    const context = logs[0].context as Context;
-    const runtime = context.runtime as Context;
-    expect(runtime.file).toMatch("winston.test.ts");
+    const context = logs[0].context;
+    expect(context.runtime.file).toMatch("winston.test.ts");
   });
 });