docs: re-add llamafile example (#693)

docs: Llamafile example

docs/docs/modules/model_io/models/llms/Integrations/llamafile.mdx

@@ -0,0 +1,17 @@
+---
+sidebar_label: Llamafile
+---
+import CodeBlock from "@theme/CodeBlock";
+import ExampleLlamafile from "@examples/llamafile-completion-example/llamafile_completion_example.go";
+
+# Llamafile
+
+## Running Server
+first you need have a server running.
+
+```sh 
+./mistral-7b-instruct-v0.2.Q3_K_L.llamafile  --server --nobrowser --embedding
+```
+
+
+<CodeBlock language="go">{ExampleLlamafile}</CodeBlock>

examples/llamafile-completion-example/go.mod

@@ -0,0 +1,11 @@
+module github.com/tmc/langchaingo/examples/llamafile-completion-example
+
+go 1.20
+
+require github.com/tmc/langchaingo v0.1.6
+
+require (
+	github.com/dlclark/regexp2 v1.10.0 // indirect
+	github.com/google/uuid v1.6.0 // indirect
+	github.com/pkoukk/tiktoken-go v0.1.6 // indirect
+)

examples/llamafile-completion-example/go.sum

@@ -0,0 +1,8 @@
+github.com/dlclark/regexp2 v1.10.0 h1:+/GIL799phkJqYW+3YbOd8LCcbHzT0Pbo8zl70MHsq0=
+github.com/dlclark/regexp2 v1.10.0/go.mod h1:DHkYz0B9wPfa6wondMfaivmHpzrQ3v9q8cnmRbL6yW8=
+github.com/google/uuid v1.6.0 h1:NIvaJDMOsjHA8n1jAhLSgzrAzy1Hgr+hNrb57e+94F0=
+github.com/google/uuid v1.6.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
+github.com/pkoukk/tiktoken-go v0.1.6 h1:JF0TlJzhTbrI30wCvFuiw6FzP2+/bR+FIxUdgEAcUsw=
+github.com/pkoukk/tiktoken-go v0.1.6/go.mod h1:9NiV+i9mJKGj1rYOT+njbv+ZwA/zJxYdewGl6qVatpg=
+github.com/tmc/langchaingo v0.1.6 h1:n7sce0/ougio+wbYCQ84IX1tLuaUC+mKO6WKttPVRWk=
+github.com/tmc/langchaingo v0.1.6/go.mod h1:lPpWPoAud+yQowJNRZhdtRbQCSHKF+jRxd0gU58GDHU=

examples/llamafile-completion-example/llamafile_completion_example.go

@@ -0,0 +1,43 @@
+package main
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/tmc/langchaingo/llms"
+	"github.com/tmc/langchaingo/llms/llamafile"
+	"github.com/tmc/langchaingo/schema"
+)
+
+func main() {
+
+	options := []llamafile.Option{
+		llamafile.WithEmbeddingSize(2048),
+		llamafile.WithTemperature(0.8),
+	}
+	llm, err := llamafile.New(options...)
+
+	if err != nil {
+		panic(err)
+	}
+
+	parts := []llms.ContentPart{
+		llms.TextContent{Text: "Brazil is a country? answer yes or no"},
+	}
+	content := []llms.MessageContent{
+		{
+			Role:  schema.ChatMessageTypeHuman,
+			Parts: parts,
+		},
+	}
+
+	_, err = llm.GenerateContent(context.Background(), content,
+		llms.WithStreamingFunc(func(ctx context.Context, chunk []byte) error {
+			fmt.Print(string(chunk))
+			return nil
+		}))
+
+	if err != nil {
+		panic(err)
+	}
+}