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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-19 02:57:58 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-19 02:57:58 +0000 |
commit | be1c7e50e1e8809ea56f2c9d472eccd8ffd73a97 (patch) | |
tree | 9754ff1ca740f6346cf8483ec915d4054bc5da2d /fluent-bit/GOLANG_OUTPUT_PLUGIN.md | |
parent | Initial commit. (diff) | |
download | netdata-be1c7e50e1e8809ea56f2c9d472eccd8ffd73a97.tar.xz netdata-be1c7e50e1e8809ea56f2c9d472eccd8ffd73a97.zip |
Adding upstream version 1.44.3.upstream/1.44.3upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'fluent-bit/GOLANG_OUTPUT_PLUGIN.md')
-rw-r--r-- | fluent-bit/GOLANG_OUTPUT_PLUGIN.md | 110 |
1 files changed, 110 insertions, 0 deletions
diff --git a/fluent-bit/GOLANG_OUTPUT_PLUGIN.md b/fluent-bit/GOLANG_OUTPUT_PLUGIN.md new file mode 100644 index 00000000..8ad2782e --- /dev/null +++ b/fluent-bit/GOLANG_OUTPUT_PLUGIN.md @@ -0,0 +1,110 @@ +# Fluent Bit + Golang output plugins + +The current development version of Fluent Bit, integrates support to load +_shared_ plugins built in Golang. The interface still needs some adjustment +but is functional. The expectation is to release Fluent Bit v0.10 with full +support for Go. + +## Getting Started + +Compile Fluent Bit with Golang support, e.g: + +``` +$ cd build/ +$ cmake -DFLB_DEBUG=On -DFLB_PROXY_GO=On ../ +$ make +``` + +Once compiled, we can see a new option in the binary `-e` which stands for +_external plugin_, e.g: + +``` +$ bin/fluent-bit -h +Usage: fluent-bit [OPTION] + +Available Options + -c --config=FILE specify an optional configuration file + -d, --daemon run Fluent Bit in background mode + -f, --flush=SECONDS flush timeout in seconds (default: 5) + -i, --input=INPUT set an input + -m, --match=MATCH set plugin match, same as '-p match=abc' + -o, --output=OUTPUT set an output + -p, --prop="A=B" set plugin configuration property + -e, --plugin=FILE load an external plugin (shared lib) + ... +``` + +## Build a plugin in Go + +To make easier to build plugins, we have published a _fluent-bit-go_ package: + +http://github.com/fluent/fluent-bit-go + +In the same repository we have published a plugin example called +__out_multiinstance__ that just prints the records to the standard output: + +https://github.com/fluent/fluent-bit-go/tree/master/examples/out_multiinstance + +At a minimum, a Go plugin looks like this: + +```go +package main + +import "github.com/fluent/fluent-bit-go/output" + +//export FLBPluginRegister +func FLBPluginRegister(def unsafe.Pointer) int { + // Gets called only once when the plugin.so is loaded + return output.FLBPluginRegister(ctx, "gstdout", "Stdout GO!") +} + +//export FLBPluginInit +func FLBPluginInit(plugin unsafe.Pointer) int { + // Gets called only once for each instance you have configured. + return output.FLB_OK +} + +//export FLBPluginFlushCtx +func FLBPluginFlushCtx(ctx, data unsafe.Pointer, length C.int, tag *C.char) int { + // Gets called with a batch of records to be written to an instance. + return output.FLB_OK +} + +//export FLBPluginExit +func FLBPluginExit() int { + return output.FLB_OK +} + +func main() { +} +``` + +The code above is a template to write an output plugin. It's really important +to keep the package name as `main` and add an explicit `main()` function. +This is a requirement as the code will be built as a shared library. + +To build the code above, use the following line: + +```go +$ go build -buildmode=c-shared -o out_gstdout.so out_gstdout.go +``` + +Once built, a shared library called `out_gstdout.so` will be available. It's +really important to double check the final .so file is what we expect. Doing a +`ldd` over the library we should see something similar to this: + +``` +$ ldd out_gstdout.so + linux-vdso.so.1 => (0x00007fff561dd000) + libpthread.so.0 => /lib/x86_64-linux-gnu/libpthread.so.0 (0x00007fc4aeef0000) + libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007fc4aeb27000) + /lib64/ld-linux-x86-64.so.2 (0x000055751a4fd000) +``` + +## Run Fluent Bit + the new plugin + +``` +$ bin/fluent-bit -e /path/to/out_gstdout.so -i cpu -o gstdout +``` + +For more details or assistance write to eduardo@treasure-data.com |