Ecosyste.ms: Awesome
An open API service indexing awesome lists of open source software.
https://github.com/pamburus/hl
A fast and powerful log viewer and processor that translates JSON or logfmt logs into a pretty human-readable format.
https://github.com/pamburus/hl
cli command-line-tool hl human json json-log json-logging json-logs log log-viewer logging logs rust structured-logging translates-json-logs viewer
Last synced: 27 days ago
JSON representation
A fast and powerful log viewer and processor that translates JSON or logfmt logs into a pretty human-readable format.
- Host: GitHub
- URL: https://github.com/pamburus/hl
- Owner: pamburus
- License: mit
- Created: 2020-08-04T07:19:46.000Z (over 4 years ago)
- Default Branch: master
- Last Pushed: 2024-10-29T21:46:31.000Z (about 2 months ago)
- Last Synced: 2024-10-29T21:47:21.109Z (about 2 months ago)
- Topics: cli, command-line-tool, hl, human, json, json-log, json-logging, json-logs, log, log-viewer, logging, logs, rust, structured-logging, translates-json-logs, viewer
- Language: Rust
- Homepage:
- Size: 8.55 MB
- Stars: 251
- Watchers: 3
- Forks: 10
- Open Issues: 5
-
Metadata Files:
- Readme: README.md
- License: LICENSE
Awesome Lists containing this project
- awesome-repositories - pamburus/hl - A fast and powerful log viewer and processor that translates JSON or logfmt logs into a pretty human-readable format. (Rust)
README
# hl [![Build Status][ci-img]][ci] [![Coverage Status][cov-img]][cov]
A fast and powerful log viewer and processor that translates JSON or logfmt logs into a pretty human-readable format.
High performance and convenient features are the main goals.
## Features overview
* [Automatic usage](#automatic-usage-of-pager) of the [less](https://github.com/vbwagner/less) pager by default for convenience.
* Log streaming with the `-P` flag that disables the pager.
* Log record [filtering by field key/value pairs](#filtering-by-field-values) with the `-f` option with support for hierarchical keys.
* Quick and easy [filtering by level](#quick-filtering-by-log-level) with the `-l` option.
* Quick and easy [filtering by timestamp range](#filtering-by-time-range) using the `--since` and `--until` options and intuitive formats:
* RFC-3339 timestamp format.
* Current configured timestamp output format with the `-t` option or environment variable.
* Human friendly shortcuts like `today`, `yesterday`, `friday` or relative offsets like `-3h` or `-14d`.
* Quick and easy [hiding and revealing](#hiding-or-revealing-selected-fields) of fields with the `-h` option.
* Hide empty fields with the `-e` flag.
* Lightning fast [message sorting](#sorting-messages-chronologically) with automatic indexing for local files using the `-s` flag.
* Handles ~1 GiB/s for the first scan and allows fast filtering by timestamp range and level without scanning the data afterwards.
* Works fast with hundreds of local files containing hundreds of gigabytes of data.
* Reindexes large, growing files at lightning speed, skipping unmodified blocks, ~10 GiB/s.
* [Follow mode](#sorting-messages-chronologically-with-following-the-changes) with live message sorting by timestamp from different sources using the `-F` flag and preview of several recent messages with the `--tail` option.
* Custom complex [queries](#performing-complex-queries) that can include and/or conditions and much more.
* Non-JSON prefixes with `--allow-prefix` flag.
* Displays timestamps in UTC by default and supports easy timezone switching with the `-Z` option and the `-L` flag for a local timezone.
* Customizable via [configuration](#configuration-files) file and environment variables, supports easy [theme switching](#selecting-current-theme) and custom [themes](#custom-themes).
## Performance comparison chart
### Performance comparison with [humanlog](https://github.com/humanlogio/humanlog), [hlogf](https://github.com/ssgreg/hlogf) and [fblog](https://github.com/brocode/fblog) on a 2.3 GiB log file
* See [performance](#performance) section for more details.
## Installation options
* Install using [homebrew](https://brew.sh) on macOS or Linux
```sh
brew install pamburus/tap/hl
```
* Download and extract using `curl` and `tar` on macOS
```sh
curl -sSfL https://github.com/pamburus/hl/releases/latest/download/hl-macos.tar.gz | tar xz
```
* Download and extract using `curl` and `tar` on Linux
```sh
curl -sSfL https://github.com/pamburus/hl/releases/latest/download/hl-linux-x86_64-musl.tar.gz | tar xz
```
* Install [AUR package](https://aur.archlinux.org/packages/hl-log-viewer-bin) on Arch Linux
```sh
yay -S hl-log-viewer-bin
```
* Install using [cargo](https://www.rust-lang.org/tools/install)
```sh
cargo install --locked --git https://github.com/pamburus/hl.git
```
* Download latest release from [download page](https://github.com/pamburus/hl/releases/latest)
## Examples
### Screenshot
See other [screenshots](https://github.com/pamburus/hl-extra/tree/90be58af2fb91d5b5e7ce3b74c3b567611379c40/screenshot#readme)
## Features and usage
### Concatenation of multiple log files
* Concatenate all log files
Command
```sh
hl *.log
```
Concatenates and displays all `*.log` files found in the current directory.
### Support for gzipped log files
* Concatenate all log files including gzipped log files
Command
```sh
hl $(ls -tr /var/log/example/*.{log,log.gz})
```
Concatenates and displays all `*.log` and `*.log.gz` files found in `/var/log/example/`.
### Automatic usage of pager
* Use the default pager with the default parameters
Command
```sh
hl example.log
```
Automatically opens `less` pager with the default parameters.
* Override options for default pager
Command
```sh
LESS=-SR hl example.log
```
Opens `less` pager with disabled line wrapping.
* Use custom pager
Command
```sh
PAGER="most -w" hl example.log
```
Opens `most` pager with `-w` option.
### Quick filtering by log level
* Errors only
Command
```sh
hl -l e
```
Displays only error log level messages.
* Errors and warnings
Command
```sh
hl -l w
```
Displays only warning and error log level messages.
* Errors, warnings and informational
Command
```sh
hl -l i
```
Displays all log messages except debug level messages.
### Using live log streaming
* Command
```sh
tail -f example.log | hl -P
```
Tracks changes in the example.log file and displays them immediately.
Flag `-P` disables automatic using of pager in this case.
### Filtering by field values
* Command
```sh
hl example.log --filter component=tsdb
```
Displays only messages where the `component` field has the value `tsdb`.
* Command
```sh
hl example.log -f component!=tsdb -f component!=uninteresting
```
Displays only messages where the `component` field has a value other than `tsdb` or `uninteresting`.
* Command
```sh
hl example.log -f provider~=string
```
Displays only messages where the `provider` field contains the `string` sub-string.
* Command
```sh
hl example.log -f 'provider!~=string'
```
Displays only messages where the `provider` field does not contain the `string` sub-string.
### Performing complex queries
* Command
```sh
hl my-service.log --query 'level > info or status-code >= 400 or duration > 0.5'
```
Displays messages that either have a level higher than info (i.e. warning or error) or have a status code field with a numeric value >= 400 or a duration field with a numeric value >= 0.5.
* Command
```sh
hl my-service.log -q '(request in (95c72499d9ec, 9697f7aa134f, bc3451d0ad60)) or (method != GET)'
```
Displays all messages that have the 'request' field with one of these values, or the 'method' field with a value other than 'GET'.
* Complete set of supported operators
* Logical operators
* Logical conjunction - `and`, `&&`
* Logical disjunction - `or`, `||`
* Logical negation - `not`, `!`
* Comparison operators
* Equal - `eq`, `=`
* Not equal - `ne`, `!=`
* Greater than - `gt`, `>`
* Greater or equal - `ge`, `>=`
* Less than - `lt`, `<`
* Less or equal - `le`, `<=`
* String matching operators
* Sub-string check - (`contain`, `~=`), (`not contain`, `!~=`)
* Wildcard match - (`like`), (`not like`)
* Wildcard characters are: `*` for zero or more characters and `?` for a single character
* Regular expression match - (`match`, `~~=`), (`not match`, `!~~=`)
* Operators with sets
* Test if value is one of the values in a set - `in (v1, v2)`, `not in (v1, v2)`
* Test if value is one of the values in a set loaded from a file - `in @filename`, `not in @filename`, assuming that each element is a line in the file, which can be either a simple string or a JSON string
* Test if value is one of the values in a set loaded stdin - `in @-`, `not in @-`
* Notes
* Special field names that are reserved for filtering by predefined fields regardless of the actual source field names used to load the corresponding value: `level`, `message`, `caller` and `logger`.
* To address a source field with one of these names instead of predefined fields, add a period before its name, i.e., `.level` will perform a match against the "level" source field.
* To address a source field by its exact name, use a JSON-formatted string, i.e. `-q '".level" = info'`.
* To specify special characters in field values, also use a JSON-formatted string, i.e.
```sh
hl my-service.log -q 'message contain "Error:\nSomething unexpected happened"'
```
### Filtering by time range
* Command
```sh
hl example.log --since 'Jun 19 11:22:33' --until yesterday
```
Displays only messages that occurred after Jun 19 11:22:33 UTC of the current year (or the previous year if the current date is less than Jun 19 11:22:33) and before yesterday midnight.
* Command
```sh
hl example.log --since -3d
```
Displays only messages from the past 72 hours.
* Command
```sh
hl example.log --until '2021-06-01 18:00:00' --local
```
Displays only messages that occurred before 6 PM local time on June 1, 2021, and shows timestamps in local time.
### Hiding or revealing selected fields
* Command
```sh
hl example.log --hide provider
```
Hides field `provider`.
* Command
```sh
hl example.log --hide '*' --hide '!provider'
```
Hides all fields except `provider`.
* Command
```sh
hl example.log -h headers -h body -h '!headers.content-type'
```
Hides fields `headers` and `body` but shows a single sub-field `content-type` inside field `headers`.
### Sorting messages chronologically
* Command
```sh
hl -s *.log
```
Displays log messages from all log files in the current directory sorted in chronological order.
### Sorting messages chronologically with following the changes
* Command
```sh
hl --sync-interval-ms 500 -F <(kubectl logs -l app=my-app-1 -f) <(kubectl logs -l app=my-app-2 -f)
```
Runs without a pager in follow mode by merging messages from the outputs of these 2 commands and sorting them chronologically within a custom 500ms interval.
* Command
```sh
hl -F --tail 100 app1.log app2.log app3.log
```
Runs without a pager in follow mode, following the changes in three log files in the current directory and sorting them chronologically at a default interval of 100ms.
Preloads 100 lines from the end of each file before filtering.
### Configuration files
* Configuration file is automatically loaded if found in a predefined platform-specific location.
| OS | Location |
| ------- | --------------------------------------------------------- |
| macOS | ~/.config/hl/config.{yaml,toml,json} |
| Linux | ~/.config/hl/config.{yaml,toml,json} |
| Windows | %USERPROFILE%\AppData\Roaming\hl\config.{yaml,toml,json} |
* The path to the configuration file can be overridden using the HL_CONFIG environment variable.
* All parameters in the configuration file are optional and can be omitted. In this case, default values are used.
#### Default configuration file
* [config.yaml](etc/defaults/config.yaml)
### Environment variables
* Many parameters that are defined in command line arguments and configuration files can also be specified by environment variables.
#### Precedence of configuration sources (from lowest priority to highest priority)
* Configuration file
* Environment variables
* Command-line arguments
#### Environment variables examples
* `HL_TIME_FORMAT='%y-%m-%d %T.%3N'` overrides the time format specified in the configuration file.
* `HL_TIME_ZONE=Europe/Berlin` overrides the time zone specified in the configuration file.
* `HL_CONCURRENCY=4` overrides the concurrency limit specified in the configuration file.
* `HL_PAGING=never` specifies the default value for the paging option, but it can be overridden by command line arguments.
### Themes
#### Stock themes
* [themes](etc/defaults/themes/)
#### Selecting current theme
* Using `theme` value in the configuration file.
* Using environment variable, i.e. `HL_THEME=classic`, overrides the value specified in configuration file.
* Using command-line argument, i.e. `--theme classic`, overrides all other values.
#### Selecting themes with preview
To select themes with preview [fzf](https://github.com/junegunn/fzf) tool can be used like this:
```bash
hl --list-themes | fzf --preview-window="top,80%" --preview="head -n 100 example.log | hl -c --theme {}"
```
#### Custom themes
* Custom themes are automatically loaded when found in a predefined platform-specific location.
| OS | Location |
| ------- | ---------------------------------------------------------- |
| macOS | ~/.config/hl/themes/*.{yaml,toml,json} |
| Linux | ~/.config/hl/themes/*.{yaml,toml,json} |
| Windows | %USERPROFILE%\AppData\Roaming\hl\themes\*.{yaml,toml,json} |
* Format description
* Section `elements` contains styles for predefined elements.
* Section `levels` contains optional overrides for styles defined in `elements` sections per logging level, which are [`debug`, `info`, `warning`, `error`].
* Each element style contains optional `background`, `foreground` and `modes` parameters.
* Example
```yaml
elements:
:
foreground:
background:
modes: [, , ...]
levels:
:
:
foreground:
background:
modes: [, , ...]
```
* Color format is one of
* Keyword `default` specifies default color defined by the terminal.
* ASCII basic color name, one of
* `black`
* `red`
* `green`
* `yellow`
* `blue`
* `magenta`
* `cyan`
* `white`
* `bright-black`
* `bright-red`
* `bright-green`
* `bright-yellow`
* `bright-blue`
* `bright-magenta`
* `bright-cyan`
* `bright-white`
* 256-color palette code, from `0` to `255`.
* RGB color in hex web color format, i.e. `#FFFF00` for bright yellow color.
* Modes is a list of additional styles, each of them is one of
* `bold`
* `faint`
* `italic`
* `underline`
* `slow-blink`
* `rapid-blink`
* `reverse`
* `conceal`
* `crossed-out`
### Used terminal color schemes
#### iTerm2
* [One Dark Neo](https://gist.github.com/pamburus/0ad130f2af9ab03a97f2a9f7b4f18c68/746ca7103726d43b767f2111799d3cb5ec08adbb)
* Built-in "Light Background" color scheme
#### Alacritty
* [One Dark Neo](https://gist.github.com/pamburus/e27ebf60aa17d126f5c879f06112edd6/a1e66d34a65b883f1cb8ec28820cc0c53233e3aa#file-alacritty-yml-L904)
* Note: It is recommended to use `draw_bold_text_with_bright_colors: true` setting
* [Light](https://gist.github.com/pamburus/e27ebf60aa17d126f5c879f06112edd6/a1e66d34a65b883f1cb8ec28820cc0c53233e3aa#file-alacritty-yml-L875)
* Note: It is recommended to use `draw_bold_text_with_bright_colors: false` setting
### Complete set of options and flags
```text
JSON and logfmt log converter to human readable representation
Usage: hl [OPTIONS] [FILE]...
Arguments:
[FILE]... Files to process
Options:
--config Configuration file path [env: HL_CONFIG=]
-s, --sort Sort messages chronologically
-F, --follow Follow input streams and sort messages chronologically during time frame set by --sync-interval-ms option
--tail Number of last messages to preload from each file in --follow mode [default: 10]
--sync-interval-ms Synchronization interval for live streaming mode enabled by --follow option [default: 100]
--paging Control pager usage (HL_PAGER or PAGER) [env: HL_PAGING=] [default: auto] [possible values: auto, always, never]
-P Handful alias for --paging=never, overrides --paging option
--help Print help
-V, --version Print version
Filtering Options:
-l, --level Filter messages by level [env: HL_LEVEL=]
--since
Output Options:
--color [] Color output control [env: HL_COLOR=] [default: auto] [possible values: auto, always, never]
-c Handful alias for --color=always, overrides --color option
--theme Color theme [env: HL_THEME=] [default: universal]
-r, --raw Output raw source messages instead of formatted messages, which can be useful for applying filters and saving results in their original format
--no-raw Disable raw source messages output, overrides --raw option
--raw-fields Output field values as is, without unescaping or prettifying
-h, --hide Hide or reveal fields with the specified keys, prefix with ! to reveal, specify '!*' to reveal all
--flatten Whether to flatten objects [env: HL_FLATTEN=] [default: always] [possible values: never, always]
-t, --time-format Time format, see https://man7.org/linux/man-pages/man1/date.1.html [env: HL_TIME_FORMAT=] [default: "%b %d %T.%3N"]
-Z, --time-zone Time zone name, see column "TZ identifier" at https://en.wikipedia.org/wiki/List_of_tz_database_time_zones [env: HL_TIME_ZONE=] [default: UTC]
-L, --local Use local time zone, overrides --time-zone option
--no-local Disable local time zone, overrides --local option
-e, --hide-empty-fields Hide empty fields, applies for null, string, object and array fields only [env: HL_HIDE_EMPTY_FIELDS=]
-E, --show-empty-fields Show empty fields, overrides --hide-empty-fields option [env: HL_SHOW_EMPTY_FIELDS=]
--input-info Show input number and/or input filename before each message [default: auto] [possible values: auto, none, full, compact, minimal]
-o, --output Output file
Input Options:
--input-format Input format [env: HL_INPUT_FORMAT=] [default: auto] [possible values: auto, json, logfmt]
--unix-timestamp-unit Unix timestamp unit [env: HL_UNIX_TIMESTAMP_UNIT=] [default: auto] [possible values: auto, s, ms, us, ns]
--allow-prefix Allow non-JSON prefixes before JSON messages [env: HL_ALLOW_PREFIX=]
--delimiter Log message delimiter, [NUL, CR, LF, CRLF] or any custom string
Advanced Options:
--interrupt-ignore-count Number of interrupts to ignore, i.e. Ctrl-C (SIGINT) [env: HL_INTERRUPT_IGNORE_COUNT=] [default: 3]
--buffer-size Buffer size [env: HL_BUFFER_SIZE=] [default: "256 KiB"]
--max-message-size Maximum message size [env: HL_MAX_MESSAGE_SIZE=] [default: "64 MiB"]
-C, --concurrency Number of processing threads [env: HL_CONCURRENCY=]
--shell-completions Print shell auto-completion script and exit [possible values: bash, elvish, fish, powershell, zsh]
--man-page Print man page and exit
--list-themes Print available themes and exit
--dump-index Print debug index metadata (in --sort mode) and exit
--debug Print debug error messages that can help with troubleshooting
```
## Performance
* MacBook Pro (16-inch, 2021)
* **CPU**: Apple M1 Max CPU
* **OS**: macOS Sonoma 14.4.1
* **Data**: ~ **2.3 GiB** log file, **6 000 000** lines
* [hl](https://github.com/pamburus/hl) **v0.28.0** ~ *1.4 seconds*
```sh
$ time hl example.log -c -o /dev/null
hl example.log -c -o /dev/null 11.74s user 0.53s system 885% cpu 1.386 total
```
* [hlogf](https://github.com/ssgreg/hlogf) **v1.4.1** ~ *8.5 seconds*
```sh
$ time hlogf example.log --color always >/dev/null
hlogf example.log --color always > /dev/null 6.93s user 1.79s system 99% cpu 8.757 total
```
* [humanlog](https://github.com/humanlogio/humanlog) **v0.7.6** ~ *77 seconds*
```sh
$ time humanlog /dev/null
humanlog> reading stdin...
humanlog --color always < example.log > /dev/null 80.02s user 4.71s system 109% cpu 1:17.11 total
```
* [fblog](https://github.com/brocode/fblog) **v4.9.0** ~ *36 seconds*
```sh
$ time fblog example.log >/dev/null
fblog example.log > /dev/null 32.48s user 2.03s system 97% cpu 35.526 total
```
* [fblog](https://github.com/brocode/fblog) with `-d` flag **v4.9.0** ~ *148 seconds*
```sh
$ time fblog -d example.log >/dev/null
fblog -d example.log > /dev/null 132.12s user 14.39s system 99% cpu 2:27.61 total
```
* See [#132](https://github.com/pamburus/hl/issues/132) for how to repeat measurements
[ci-img]: https://github.com/pamburus/hl/actions/workflows/ci.yml/badge.svg
[ci]: https://github.com/pamburus/hl/actions/workflows/ci.yml
[cov-img]: https://codecov.io/gh/pamburus/hl/graph/badge.svg?token=464MN13408
[cov]: https://codecov.io/gh/pamburus/hl