{"id":18021436,"url":"https://github.com/suda/leno","last_synced_at":"2026-02-11T17:01:19.843Z","repository":{"id":42629752,"uuid":"318283376","full_name":"suda/leno","owner":"suda","description":"🌲️ Command-line log viewer with a web UI","archived":false,"fork":false,"pushed_at":"2024-08-30T16:54:14.000Z","size":721,"stargazers_count":6,"open_issues_count":4,"forks_count":0,"subscribers_count":1,"default_branch":"main","last_synced_at":"2026-01-17T06:26:18.155Z","etag":null,"topics":["logging","logs","webui"],"latest_commit_sha":null,"homepage":"","language":"Svelte","has_issues":true,"has_wiki":null,"has_pages":null,"mirror_url":null,"source_name":null,"license":"mit","status":null,"scm":"git","pull_requests_enabled":true,"icon_url":"https://github.com/suda.png","metadata":{"files":{"readme":"README.md","changelog":null,"contributing":null,"funding":".github/FUNDING.yml","license":"LICENSE","code_of_conduct":"CODE_OF_CONDUCT.md","threat_model":null,"audit":null,"citation":null,"codeowners":null,"security":null,"support":null,"governance":null,"roadmap":null,"authors":null,"dei":null,"publiccode":null,"codemeta":null,"zenodo":null,"notice":null,"maintainers":null,"copyright":null,"agents":null,"dco":null,"cla":null},"funding":{"github":"suda","open_collective":"wojtek-siudzinski","ko_fi":"sudapl"}},"created_at":"2020-12-03T18:24:27.000Z","updated_at":"2023-12-23T06:35:18.000Z","dependencies_parsed_at":"2022-09-01T23:01:54.399Z","dependency_job_id":null,"html_url":"https://github.com/suda/leno","commit_stats":null,"previous_names":[],"tags_count":1,"template":false,"template_full_name":null,"purl":"pkg:github/suda/leno","repository_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/suda%2Fleno","tags_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/suda%2Fleno/tags","releases_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/suda%2Fleno/releases","manifests_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/suda%2Fleno/manifests","owner_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners/suda","download_url":"https://codeload.github.com/suda/leno/tar.gz/refs/heads/main","sbom_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories/suda%2Fleno/sbom","scorecard":null,"host":{"name":"GitHub","url":"https://github.com","kind":"github","repositories_count":286080680,"owners_count":29338650,"icon_url":"https://github.com/github.png","version":null,"created_at":"2022-05-30T11:31:42.601Z","updated_at":"2026-02-11T16:14:43.024Z","status":"ssl_error","status_checked_at":"2026-02-11T16:14:15.258Z","response_time":97,"last_error":"SSL_connect returned=1 errno=0 peeraddr=140.82.121.6:443 state=error: unexpected eof while reading","robots_txt_status":"success","robots_txt_updated_at":"2025-07-24T06:49:26.215Z","robots_txt_url":"https://github.com/robots.txt","online":false,"can_crawl_api":true,"host_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub","repositories_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repositories","repository_names_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/repository_names","owners_url":"https://repos.ecosyste.ms/api/v1/hosts/GitHub/owners"}},"keywords":["logging","logs","webui"],"created_at":"2024-10-30T06:09:57.645Z","updated_at":"2026-02-11T17:01:19.789Z","avatar_url":"https://github.com/suda.png","language":"Svelte","funding_links":["https://github.com/sponsors/suda","https://opencollective.com/wojtek-siudzinski","https://ko-fi.com/sudapl"],"categories":[],"sub_categories":[],"readme":"\u003cdiv align=\"center\"\u003e\n\t\u003cimg src=\"assets/logo.png\"\u003e\n\t\u003cp\u003e\n\t\t\u003cb\u003eCommand line log viewer with a web UI\u003c/b\u003e\n\t\u003c/p\u003e\n\t\u003cbr\u003e\n\t\u003ca href=\"https://contributionswelcome.org/\"\u003e\u003cimg src=\"https://img.shields.io/badge/contributions-welcome-7dcfef\" /\u003e\u003c/a\u003e\n\t\u003ca href=\"https://choosealicense.com/licenses/mit/\"\u003e\u003cimg src=\"https://img.shields.io/github/license/suda/go-gooey\" /\u003e\u003c/a\u003e\n\t\u003cbr\u003e\n\t\u003cbr\u003e\n\u003c/div\u003e\n\nLeño is a [JSON lines](https://jsonlines.org/) log viewer with a web UI. Think of it as local Kibana/Sumo Logic for development. Works great with [Pino](https://getpino.io/) logging library, any other app that logs into JSON, or nginx/nginx-ingress access logs.\n\n![](./assets/screenshot.png)\n\n## Installation\n\nDownload the latest binary for your platform from the [releases page](https://github.com/suda/leno/releases) and place it somewhere on your `$PATH`.\n\nOr build from source (requires Go 1.21+ and Node.js for the Svelte build step):\n\n```sh\ngit clone https://github.com/suda/leno\ncd leno\nnpm install\nmake build\n```\n\nThis produces a single `./leno` binary with the web UI embedded — no runtime dependencies.\n\n## Usage\n\nPipe your app's output to `leno`:\n\n```sh\n$ ./myapp | leno\nLeno running on http://localhost:3000\n```\n\nNow open [http://localhost:3000](http://localhost:3000) to see logs stream in real time.\n\n### Custom port\n\n```sh\n$ LENO_PORT=8080 ./myapp | leno\nLeno running on http://localhost:8080\n```\n\n### Example with Pino\n\n```sh\n$ node server.js | leno\n```\n\n### Nginx / nginx-ingress access logs\n\nUse `--log-format=nginx` to parse nginx access logs (both the standard [combined log format](https://nginx.org/en/docs/http/ngx_http_log_module.html) and the extended [nginx-ingress format](https://kubernetes.github.io/ingress-nginx/user-guide/nginx-configuration/log-format/)). Each line is converted to a JSON object before display.\n\n```sh\n# Local nginx\n$ tail -f /var/log/nginx/access.log | leno --log-format=nginx\n\n# Kubernetes nginx-ingress\n$ kubectl logs -n nginx -l app.kubernetes.io/name=ingress-nginx \\\n    --all-containers=true -f | leno --log-format=nginx\n```\n\nThe following fields are extracted:\n\n| Field | Type | Description |\n|---|---|---|\n| `remote_addr` | string | Client IP address |\n| `remote_user` | string | Authenticated user (`-` if none) |\n| `time` | string | Request time in RFC 3339 UTC |\n| `method` | string | HTTP method |\n| `path` | string | Request path |\n| `http_version` | string | HTTP version |\n| `status` | number | HTTP response status code |\n| `body_bytes` | number | Bytes sent to client |\n| `http_referer` | string | `Referer` header |\n| `http_user_agent` | string | `User-Agent` header |\n| `request_length` | number | *(nginx-ingress)* Request size in bytes |\n| `request_time` | number | *(nginx-ingress)* Request processing time in seconds |\n| `upstream_name` | string | *(nginx-ingress)* Upstream service name |\n| `upstream_addr` | string | *(nginx-ingress)* Upstream pod address |\n| `upstream_response_time` | string | *(nginx-ingress)* Upstream response time(s) |\n| `upstream_status` | number | *(nginx-ingress)* Upstream response status code |\n| `request_id` | string | *(nginx-ingress)* Unique request ID |\n\nLines that don't match either format are passed through as-is, so mixed log streams (e.g. nginx error lines alongside access lines) are handled gracefully.\n\n### Generate fake logs for testing\n\n```sh\n$ ./scripts/generate-fake-logs.sh | leno\n```\n\n## Building from source\n\nRequirements: Go 1.21+, Node.js (build only)\n\n```sh\n# Install JS build dependencies\nnpm install\n\n# Build Svelte app and compile Go binary\nmake build        # produces ./leno\n\n# Development (Svelte hot-reload)\nmake dev          # runs rollup in watch mode; run ./leno separately\n\n# Clean build artifacts\nmake clean\n```\n\n## Credits\n\nLeño's logo is based on [log by Smalllike](https://thenounproject.com/term/log/2784204) from the Noun Project.","project_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fsuda%2Fleno","html_url":"https://awesome.ecosyste.ms/projects/github.com%2Fsuda%2Fleno","lists_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Fsuda%2Fleno/lists"}