Linager is a sophisticated static analysis tool for Go that tracks data lineage, dependencies, and usage patterns within your codebase. It provides detailed insights about how data flows through your application, making it easier to understand, refactor, and maintain complex code.
- Data Flow Analysis: Track where variables and fields are defined, read, and written
- Dependency Tracking: Identify data dependencies between variables and functions
- Conditional Execution: Capture conditions under which data is accessed or modified
- Struct Field Analysis: Detailed tracking of struct fields and their usage
- Generic Types Support: Full analysis of generic type parameters and instantiations
- Call Graph Analysis: Understand transitive dependencies through function calls
- Rich Metadata: Capture additional context like struct tags and parameter info
go get github.com/viant/linagerpackage main
import (
"fmt"
"github.com/viant/linager/analyzer"
"gopkg.in/yaml.v3"
)
func main() {
code := `
package main
type User struct {
ID int ` + "`json:\"id\"`" + `
Name string ` + "`json:\"name\"`" + `
}
func main() {
user := User{ID: 1, Name: "John"}
id := user.ID
fmt.Println(id)
}
`
dataPoints, err := analyzer.AnalyzeSourceCode(code, "", "example.go")
if err != nil {
fmt.Printf("Analysis error: %v\n", err)
return
}
data, _ := yaml.Marshal(dataPoints)
fmt.Println(string(data))
}package main
import (
"fmt"
"github.com/viant/linager/analyzer"
"gopkg.in/yaml.v3"
"os"
)
func main() {
// Load and analyze an entire project
pkgs, err := analyzer.LoadProject("path/to/project")
if err != nil {
fmt.Printf("Error loading project: %v\n", err)
return
}
dataPoints, err := analyzer.AnalyzePackages(pkgs)
if err != nil {
fmt.Printf("Analysis error: %v\n", err)
return
}
data, _ := yaml.Marshal(dataPoints)
os.WriteFile("analysis.yaml", data, 0644)
}Linager uses a structured data model to represent the results of its analysis:
A DataPoint represents information about an identifier (variable, struct field, function):
type DataPoint struct {
Identity Identity // Identity information
Definition CodeLocation // Where the identifier is defined
Metadata map[string]interface{} // Additional metadata
Writes []*TouchPoint // Where the identifier is written
Reads []*TouchPoint // Where the identifier is read
}A TouchPoint represents a location where data is accessed or modified:
type TouchPoint struct {
CodeLocation CodeLocation // Location in code
Context TouchContext // Context information
Dependencies []IdentityRef // Dependencies for this touch point
ConditionalExpression string // Condition under which this happens
}For the following code:
package analyzer
type Foo struct {
Name string
Score int
}
type Bar struct {
Name string
}
func main() {
b := Bar{Name: "XXXX"}
p := Foo{Name: "John", Score: 30}
if p.Score > 18 {
p.Name = "Adult: " + b.Name
}
}Linager produces detailed analysis like:
- identity:
ref: main:Foo:Name
pkgPath: main
package: main
holderType: Foo
name: Name
kind: string
definition:
filePath: main.go
lineNumber: 4
writes:
- codeLocation:
filePath: main.go
lineNumber: 15
columnStart: 11
columnEnd: 23
context:
function: main
- codeLocation:
filePath: main.go
lineNumber: 17
columnStart: 3
columnEnd: 9
context:
function: main
dependencies:
- b
- main:Bar:Name
- identity:
ref: main:Foo:Score
pkgPath: main
package: main
holderType: Foo
name: Score
kind: int
definition:
filePath: main.go
lineNumber: 5
writes:
- codeLocation:
filePath: main.go
lineNumber: 15
columnStart: 25
columnEnd: 34
context:
function: main
- identity:
ref: main:Bar:Name
pkgPath: main
package: main
holderType: Bar
name: Name
kind: string
definition:
filePath: main.go
lineNumber: 9
writes:
- codeLocation:
filePath: main.go
lineNumber: 13
columnStart: 11
columnEnd: 23
context:
function: main
reads:
- codeLocation:
filePath: main.go
lineNumber: 17
columnStart: 24
columnEnd: 30
context:
function: main
- codeLocation:
filePath: main.go
lineNumber: 17
columnStart: 24
columnEnd: 30
context:
function: main
- codeLocation:
filePath: main.go
lineNumber: 17
columnStart: 24
columnEnd: 30
context:
function: main
- identity:
ref: b
name: b
kind: main.Bar
definition:
filePath: main.go
lineNumber: 13
writes:
- codeLocation:
filePath: main.go
lineNumber: 13
columnStart: 2
columnEnd: 3
context:
function: main
dependencies:
- Name
reads:
- codeLocation:
filePath: main.go
lineNumber: 17
columnStart: 24
columnEnd: 25
context:
function: main
- codeLocation:
filePath: main.go
lineNumber: 17
columnStart: 24
columnEnd: 25
context:
function: main
- codeLocation:
filePath: main.go
lineNumber: 17
columnStart: 24
columnEnd: 25
context:
function: main
- identity:
ref: Name
name: Name
kind: string
definition:
filePath: main.go
lineNumber: 13
- identity:
ref: p
name: p
kind: main.Foo
definition:
filePath: main.go
lineNumber: 15
writes:
- codeLocation:
filePath: main.go
lineNumber: 15
columnStart: 2
columnEnd: 3
context:
function: main
dependencies:
- Score
- Name
reads:
- codeLocation:
filePath: main.go
lineNumber: 17
columnStart: 3
columnEnd: 4
context:
function: main
- identity:
ref: Score
name: Score
kind: int
definition:
filePath: main.go
lineNumber: 15
Linager provides detailed analysis of generic types:
type Container[T any] struct {
Value T
}
func Process[T comparable](c Container[T]) T {
return c.Value
}
func main() {
intContainer := Container[int]{Value: 42}
intValue := Process(intContainer)
}Linager extracts and analyzes struct tags:
type User struct {
ID int `json:"id" db:"user_id"`
Email string `json:"email" validate:"required,email"`
CreatedAt time.Time `json:"created_at" db:"created_at"`
}Contributions to Linager are welcome! Please feel free to submit a Pull Request.
The source code is made available under the terms of the Apache License, Version 2, as stated in the file LICENSE.
Individual files may be made available under their own specific license, all compatible with Apache License, Version 2. Please see individual files for details.
Developed and maintained by Viant.