feat: add transport option and golangci-lint

.github/workflows/lint.yml

@@ -0,0 +1,26 @@
+name: Lint
+
+on:
+  push:
+    branches: [master, main]
+  pull_request:
+    branches: [master, main]
+
+jobs:
+  golangci:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout Code
+        uses: actions/[email protected]
+
+      - name: Install Go
+        uses: actions/[email protected]
+        with:
+          go-version-file: go.mod
+          cache-dependency-path: go.sum
+
+      - name: Lint
+        uses: golangci/[email protected]
+        with:
+          github-token: ${{ secrets.GITHUB_TOKEN }}
+          version: v2.2.1

.github/workflows/testing.yml

@@ -2,28 +2,27 @@ name: Testing
 
 on:
   push:
-    branches: [ master ]
+    branches: [master]
   pull_request:
-    branches: [ master ]
+    branches: [master]
 
 jobs:
-
   build:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v2
+      - name: Install Go
+        uses: actions/setup-go@v5
+        with:
+          go-version: "1.20.x"
+
+      - name: Checkout Code
+        uses: actions/checkout@v4
 
-    - name: Set up Go
-      uses: actions/setup-go@v2
-      with:
-        go-version: 1.18
+      - name: Test
+        run: go test -v -timeout 30m -race ./... -coverprofile=coverage.txt -covermode=atomic
 
-    - name: Vet
-      run: go vet ./...
-    - name: Test
-      run: go test -v -timeout 30m -race ./... -coverprofile=coverage.txt -covermode=atomic
-
-    - name: Upload coverage reports to Codecov
-      uses: codecov/codecov-action@v3
-      env:
-        CODECOV_TOKEN: ${{ secrets.CODECOV_TOKEN }}
+      - name: Upload coverage reports to Codecov
+        uses: codecov/codecov-action@v4
+        with:
+          token: ${{ secrets.CODECOV_TOKEN }}
+          slug: wenchy/requests

.golangci.yaml

@@ -0,0 +1,35 @@
+---
+version: "2"
+linters:
+  default: none
+  enable:
+    - errcheck
+    - govet
+    # - gosec
+    - ineffassign
+    - staticcheck
+    - unused
+    - misspell
+  exclusions:
+    # presets:
+    #   - comments
+    #   - common-false-positives
+    #   - legacy
+    #   - std-error-handling
+    rules:
+      - linters:
+          - staticcheck
+        text: "QF1008:" # could remove embedded field "XXX" from selector (staticcheck)
+      - linters:
+          - staticcheck
+        text: "QF1007:" # could merge conditional assignment into variable declaration (staticcheck)
+      - linters:
+          - staticcheck
+        text: "QF1001:" # could apply De Morgan's law (staticcheck)
+      - linters:
+          - staticcheck
+        text: "QF1006:" # could lift into loop condition (staticcheck)
+formatters:
+  enable:
+    - gofmt
+    - gofumpt

env.go

@@ -12,15 +12,23 @@
 	// caches them for reuse by subsequent calls. It uses HTTP proxies as
 	// directed by the environment variables HTTP_PROXY, HTTPS_PROXY and
 	// NO_PROXY (or the lowercase versions thereof).
-	transport   *http.Transport
+	transport *http.Transport
+	// hostRoundTrippers specify the host-specific RoundTripper to use for the
+	// request. If not found, http.DefaultTransport is used.
+	hostRoundTrippers map[string]http.RoundTripper
+	// interceptor intercepts each HTTP request.
 	interceptor InterceptorFunc
 }
 
 var env environment
 
 func init() {
-	env.timeout = 60 * time.Second                                  // default timeout
-	env.transport = http.DefaultTransport.(*http.Transport).Clone() // default transport
+	env.timeout = 60 * time.Second // default timeout
+	transport, ok := http.DefaultTransport.(*http.Transport)
+	if !ok {
+		panic("Ooh! http.DefaultTransport's underlying is not *http.Transport. Maybe golang team has changed it.")
+	}
+	env.transport = transport
 }
 
 // SetEnvTimeout sets the default timeout for each HTTP request at
@@ -53,7 +61,7 @@
 	}
 }
 
-// getChainDo recursively generates the chained do.
+// getChainDo generates the chained do recursively.
 func getChainDo(interceptors []InterceptorFunc, curr int, finalDo Do) Do {
 	if curr == len(interceptors)-1 {
 		return finalDo
@@ -62,3 +70,15 @@
 		return interceptors[curr+1](ctx, r, getChainDo(interceptors, curr+1, finalDo))
 	}
 }
+
+// SetHostTransport sets the host-specific RoundTripper to use for the request.
+//
+// # Example
+//
+//	SetHostTransport(map[string]http.RoundTripper{
+//	    "example1.com": http.DefaultTransport,
+//	    "example2.com": MyCustomTransport,
+//	})
+func SetHostTransport(rts map[string]http.RoundTripper) {
+	env.hostRoundTrippers = rts
+}

go.mod

@@ -1,10 +1,11 @@
 module github.com/Wenchy/requests
 
-go 1.18
+go 1.20
+
+require github.com/stretchr/testify v1.9.0
 
 require (
 	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
-	github.com/stretchr/testify v1.9.0
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 )

options.go

@@ -42,13 +42,32 @@ type Options struct {
 	DumpRequestOut *string
 	DumpResponse   *string
 
-	// custom interceptor
+	// interceptor
 	Interceptor InterceptorFunc
+	// round tripper
+	RoundTripper http.RoundTripper
 }
 
 // Option is the functional option type.
 type Option func(*Options)
 
+// newDefaultOptions creates a new default HTTP options.
+func newDefaultOptions() *Options {
+	return &Options{
+		Headers:  http.Header{},
+		bodyType: bodyTypeDefault,
+		Timeout:  env.timeout,
+	}
+}
+
+func parseOptions(options ...Option) *Options {
+	opts := newDefaultOptions()
+	for _, setter := range options {
+		setter(opts)
+	}
+	return opts
+}
+
 // Context sets the HTTP request context.
 //
 // For outgoing client request, the context controls the entire lifetime of
@@ -351,27 +370,19 @@ func Dump(req, resp *string) Option {
 	}
 }
 
-// Interceptor specifies a custom interceptor, which is prepended to environment
-// interceptors for current request only.
+// Interceptor prepends an interceptor to environment interceptors for current
+// request only.
 func Interceptor(interceptor InterceptorFunc) Option {
 	return func(opts *Options) {
 		opts.Interceptor = interceptor
 	}
 }
 
-// newDefaultOptions creates a new default HTTP options.
-func newDefaultOptions() *Options {
-	return &Options{
-		Headers:  http.Header{},
-		bodyType: bodyTypeDefault,
-		Timeout:  env.timeout,
-	}
-}
-
-func parseOptions(options ...Option) *Options {
-	opts := newDefaultOptions()
-	for _, setter := range options {
-		setter(opts)
+// Transport specifies a custom RoundTripper for current request only.
+//
+// NOTE: If specified, then option DisableKeepAlives() will not work.
+func Transport(rt http.RoundTripper) Option {
+	return func(opts *Options) {
+		opts.RoundTripper = rt
 	}
-	return opts
 }

request.go

@@ -113,18 +113,30 @@ func do(method, url string, opts *Options, body []byte) (*Response, error) {
 	//
 	// - https://stackoverflow.com/questions/57683132/turning-off-connection-pool-for-go-http-client
 	// - https://stackoverflow.com/questions/59656164/what-is-the-difference-between-net-dialerkeepalive-and-http-transportidletimeo
-	transport := env.transport
-	if opts.DisableKeepAlives {
-		// If option DisableKeepAlives set as true, then clone a new transport
-		// just for this one-off HTTP request.
-		transport = env.transport.Clone()
-		transport.DisableKeepAlives = true
+	var roundTripper http.RoundTripper
+	if opts.RoundTripper != nil {
+		roundTripper = opts.RoundTripper
+	} else {
+		if rt := env.hostRoundTrippers[req.Host]; rt != nil {
+			// Use the host-specific RoundTripper if set.
+			roundTripper = rt
+		} else if opts.DisableKeepAlives {
+			// If option DisableKeepAlives set as true, then clone a new transport
+			// just for this one-off HTTP request.
+			transport := env.transport.Clone()
+			transport.DisableKeepAlives = true
+			roundTripper = transport
+		} else {
+			// If option DisableKeepAlives not set as true, then use the default
+			// transport.
+			roundTripper = env.transport
+		}
 	}
 	client := &Client{
 		Client: &http.Client{
 			CheckRedirect: redirector.RedirectPolicyFunc,
 			Timeout:       opts.Timeout,
-			Transport:     transport,
+			Transport:     roundTripper,
 		},
 	}
 	var ctx context.Context