# @dvelop-sdk/logging
> This package contains functions for logging with OpenTelemetry.
Latest version **1.1.1** (published 2026-09-17) · Apache-2.0 license · 0 weekly downloads
## Install
```sh
npm install @dvelop-sdk/logging
pnpm add @dvelop-sdk/logging
yarn add @dvelop-sdk/logging
bun add @dvelop-sdk/logging
```
## Health
**Score 65/100 (B)** — status: active.
Positive: has types; no vulnerabilities; has provenance; recently updated; high maintenance score.
Warnings: low downloads; no esm support.
## Facts
| | |
|---|---|
| Version | 1.1.1 |
| Published | 2026-09-17 |
| First published | 2022-04-06 |
| Weekly downloads | 0 |
| License | Apache-2.0 |
| TypeScript types | bundled |
| Module format | CommonJS |
| Dependencies | 1 |
| Unpacked size | 54.8 KB |
| Known vulnerabilities | 0 |
| Install scripts | no |
| Provenance | attested (GitHub Actions) |
| GitHub stars | 14 |
| Author | Veit Kunz |
| Maintainers | d-velop, lenklose |
## Links
- npm: https://www.npmjs.com/package/@dvelop-sdk/logging
- Repository: https://github.com/d-velop/dvelop-sdk-node
- Homepage: https://github.com/d-velop/dvelop-sdk-node#readme
- Issues: https://github.com/d-velop/dvelop-sdk-node/issues
- npm.io page: https://npm.io/package/@dvelop-sdk/logging
## Dependencies (1)
- [@dvelop-sdk/core](https://npm.io/package/@dvelop-sdk/core.md) ^3.0.0
## Recent versions
- 1.1.1 (latest) — 2026-09-17
- 1.1.0 — 2026-06-23
- 1.0.9 — 2026-04-21
- 1.0.8 — 2026-04-17
- 1.0.7 — 2026-01-23
- 1.0.6 — 2025-05-20
- 1.0.5 — 2024-07-01
- 1.0.4 — 2024-04-22
- 1.0.3 — 2024-03-26
- 1.0.2 — 2024-03-15
- 1.0.1 — 2022-08-31
- 1.0.0 — 2022-07-12
- 1.0.0-beta.9 — 2022-06-29
- 1.0.0-beta.8 — 2022-06-15
- 1.0.0-beta.7 — 2022-05-31
- … 5 more at https://npm.io/package/@dvelop-sdk/logging/versions
## README
## Just let me log
This package exposes a `DvelopLogger`-class which is initialized with a `level` and 1-n `Providers`. See [Concepts](##Concepts) for more information.
### Initialize a logger
```typescript
const logger = new DvelopLogger({
level: "info",// logs info and above
providers: [
// Providers define a logging scheme. Currently only OTEL is supported.
otelProviderFactory({
appName: "acme-myapp",
appVersion: "1.0.0",
instanceId: "0",
// Transports define where to logging statements are send. Multiple transports can be used.
transports: [
consoleTransportFactory(), // logs to console
fileTransportFactory("./logs.txt") // logs to file 'logs.txt'
]
})
],
});
```
Supported LogLevels are `debug`, `info` and `error`, represented by exposed methods.
### Start Logging
The minimal logstatement defines a level and a string to log. The OTEL-Provider transforms the information.
```typescript
logger.debug({}, "Hello World!");
/**
* {
* "time":"2022-07-07T11:06:34.105Z",
* "sev":9,
* "body":"Hello World!",
* "res":{
* "svc":{
* "name":"acme-myapp",
* "ver":"1.0.0"
* "inst": "0"
* }
* },
* "vis":1
* }
*/
```
For each method the first argument is a `DvelopContext`-object and the second argument a `DvelopLogEvent`-object.
```typescript
try {
convinceLeonidasThatThisIsMadness();
} catch (error: any) {
logger.error({
systemBaseUri: "https://sparta.d-velop.cloud",
tenantId: "T8r3cWM4JII"
}, {
name: "MissionFailedLogger",
message: "Apparently this is Sparta",
error: error,
customAttributes: {
learnings: "Don't stand near a well"
}
});
}
/**
* {
* "time":"479BCT11:11:11.111Z",
* "sev":17,
* "name":"MissionFailedLogger",
* "body":"Apparently this is Sparta",
* "tn":"T8r3cWM4JII",
* "res":{
* "svc":{
* "name":"acme-myapp",
* "ver":"1.0.0",
* "inst": "0"
* }
* },
* "attr":{
* "learnings":"Don't stand near a well",
* "exception":{
* "message":"THIS IS SPARTA",
* "type":"RoundHouseKickError",
* "stacktrace":"..."
* }
* },
* "vis":1
* }
*/
```
## Concepts
In this package logging is divided over three layers
1. Transports
2. Providers
3. Logger
### Transports
Transports are responsible for transporting a log-event. Transports are agnostic about the form of the log event.
```typescript
export type TransportFn = (event: any) => Promise;
```
There are currently two default transports supported:
```typescript
import { TransportFn, consoleTransportFactory, fileTransportFactory } from "@dvelop-sdk/logging";
const consoleTransport: TransportFn = consoleTransportFactory();
await consoleTransport("Hello World!"); // log "Hello World" to console in Node.js and Browsers
const fileTransport: TransportFn = fileTransportFactory("./logs.txt");
await fileTransport("Hello World!"); // log "Hello World" to logs.txt
```
You can easily implement your own Transport-Function:
```typescript
async function myTransport(event: any): Promise {
// jump through hoops
}
```
### Providers
Providers are able to work with the `DvelopLogEvent`-Type. The do transformation and **may** support any Transport-Functions, a subset or none (e.g a Syslog-Provider could have a UDP Transport to Port 514 baked in).
```typescript
export type ProviderFn = (context: DvelopContext, event: DvelopLogEvent, level: DvelopLogLevel) => Promise;
```
One default Provider is supported:
```typescript
import { ProviderFn, otelProviderFactory } from "@dvelop-sdk/logging";
const otel: ProviderFn = otelProviderFactory({
appName: "acme-myapp",
appVersion: "1.0.0",
instanceId: "0",
transports: [ consoleTransport, fileTransport, myTransport ]
});
```
D.velop default is to log in a JSON-Format derived from the [Open Telemetry Standard](https://opentelemetry.io/docs/reference/specification/logs/overview). The `otelProviderFactory` creates a `ProviderFn` that is responsable for according transformations (e.g. map level "info" to OTELs numeric severity of 9).
You can easily implement your own Provider-Function:
```typescript
// do a fixed provider
async function myProvider(context: DvelopContext, event: DvelopLogEvent, level: DvelopLogLevel): Promise {
// jump through hoops
}
// or have some init
async function myProviderFactory(howMuchIsTheFish: number): ProviderFn {
return (context: DvelopContext, event: DvelopLogEvent, level: DvelopLogLevel) => Promise {
// jump through hoops
}
}
// or even support generic TransportFunctions
async function myProviderFactory(transports: TransportFn[]): ProviderFn {
return (context: DvelopContext, event: DvelopLogEvent, level: DvelopLogLevel) => Promise {
const formattedEvent: any = {} // jump through hoops
transports.forEach(t => t(formattedEvent));
}
}
```
### Logger
Finally we have that can log something. The `DvelopLogger` accepts a level (everything above is logged) and 1-n provider-functions.
```typescript
const logger = new DvelopLogger({
level: "info",
providers: [
otelProviderFactory({
appName: "acme-myapp",
appVersion: "1.0.0",
instanceId: "0",
transports: [
consoleTransportFactory(),
fileTransportFactory("./logs.txt")
]
})
],
});
```
---
_Source: https://npm.io/package/@dvelop-sdk/logging · Machine-readable twin of the npm.io package page. Health data is recomputed on every publish._
