For a long time there were no official binaries for the windows platform.
One of the reasons is the complexities of the build toolchain. Not only CGO is required, but also installing the needed libraries and header files, not talking about mingw and etc.
2 weeks ago [golang-crossbuild](https://github.com/elastic/golang-crossbuild) project added native support for Libpcap based applications.
Windows support is based on the WinPcap which is a bit (a lot) outdated, BUT, since we depend only on its interface, it is still possible to use projects like npcap https://nmap.org/npcap/#download.
Npcap needs be installed with WinPcap compatibe mode (checkbox during installation)
It is also possibe install it in silent mode like this: `npcap-0.86.exe /S /winpcap_mode=yes`
After PR merge, will be updated related documentation.
Additionally fix dependency on "unix" package (apparently it can be totally replaced using universal syscall package)
### Reducing CPU context switching and number of goroutines.
Packet capture and packet processing now use only two goroutines which helps to minimize CPU context switches. Spawning too many goroutines is harmful here.
### Optimized packet capture - allocated memory only when required, and only for data which is used
Using ZeroCopy methods from libpcap library to avoid unnecessary allocations. Now memory gets allocated ONLY for the valid packets, and only for the packets which have the data. E.g. no SYN/FIN packets are used now. Additionally we now use `sync.Pool` for re-using packet objects, which helps to re-use already allocated memory.
### Simplification and optimization of request/response detection
There is no SYN/FIN packets anymore etc. Now only packet payload is used to detect start and end of the packet. More over payload detection now does not require generating a total “message” buffer, and works with individual packet payloads.
Message payloads now concatenated from packets only in the end when message is dispatched. Also, before checking if message is complete, added additional check if all received packets in the valid order, e.g. if their SEQ is valid, and no packets are missing.
Reworked chunked encoding validation, and now it does not need expensive operation of re-calculating all the chunks. Now it “trust” that client gives valid chunk body, check if packets are in the right order (e.g. SEQ match), and checks if message ends with the right suffix. All is done with 0 allocations.
Parsing all Headers using `proto.GetHeaders` was proved to be very slow. Now we only parse the headers we need(and do it only once).
Packets gets matched together using ACK, which on high RPS removed chances of duplicating IDs. Additionally, even if packets are received out of order, now it will properly sort them, before dispatching the message.
### Changes in ID generation algorithm
Message ID generation and relations between request and response IDs is fully rewritten. Responses now do not have to lookup for request data in order to get the same ID. ID no rely on the fact that SEQ of the first packet of the response should be the same as ACK of the request. If previously Message ID contained random values, like current timestamp, now it has a consistent algorithm which is based on TCP stream id (SrcPort + DstPort + SrcIP/DstIP) and current ACK/SEQ number (to distinguish multiple messages within the same stream).
### BPF filter optimizations
When tracking response it now uses a more accurate BPF rule to filter only needed traffic.
### Misc
The packet code is now fully moved to tcp/Packet, so packet processing done only once in one place.
TCP output now has a 5 second timeout, and has a proper Close method.
Fully switching to go modules and removing vendoring.
## Description
Hi 👋 I ran the [DeepSource](https://deepsource.io/) static analyzer on the forked copy of this repo and found some [interesting code quality issues](https://deepsource.io/gh/ankitdobhal/goreplay/issues/). This PR fixes a few of them.
## Summary of Fixes
- Added .deepsource.toml to fix bug risks
- Empty string test can be improved
- Nested if can be replaced with else-if
## Type of change
- [✔] Antipattern
- [ ] New feature (non-breaking change which adds functionality)
## Checklist:
- [✔] My code follows the style guidelines of this project
- [ ] I have performed a self-review of my own code
- [ ] I have commented my code, particularly in hard-to-understand areas
- [ ] I have made corresponding changes to the documentation
bugs include:
- middleware doesn't send message meta
- send empty request when prettifier is off
- handle shutdown gracefully
- disable debug in example middlewares during test
fixes#880👍
Update Dockerfile
- fix alpine image version
- add RELEASE_VERSION build arg
Add githubAction to build & push docker image on github release published event
- add github workflow file
- add dependabot file to automatically propose PRs on githubActions version update*
> ⚠️ *Note1: you will have to add `DOCKERHUB_USERNAME` and `DOCKERHUB_TOKEN` as github secrets in order for the
> ⚠️ *Note2: github dependabot support must be enabled in order for this action to work
githubAction to be able to login to the dockerHub and push images on it 👍
> *Note3: we can add other dependabot entries in order to update Go modules and Dockerfile base images 👍 (i.e `FROM` parts)
the current UUID generator runs at:
```
BenchmarkMessageUUID 13599342 87.7 ns/op 16 B/op 0 allocs/op
```
with the former version that was running on
```
BenchmarkMessageUUID 2818203 427 ns/op 96 B/op 2 allocs/op
```
it fixes#842#851
// PluginReader is an interface for input plugins
type PluginReader interface {
PluginRead() (msg *Message, err error)
}
// PluginWriter is an interface for output plugins
type PluginWriter interface {
PluginWrite(msg *Message) (n int, err error)
}
