Use http library instead of chi (#48)

SVilgelm · web-flow · commit 08da0812ea3d · 2024-11-24T03:34:49.000Z
- Reduce the number of external dependencies by using standart http library instead of chi.
- Use text/template for text based responses.
diff --git a/.github/workflows/checks.yaml b/.github/workflows/checks.yaml
@@ -26,33 +26,33 @@ jobs:
 
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
 
       - name: Initialize CodeQL
-        uses: github/codeql-action/init@v3
+        uses: github/codeql-action/init@ea9e4e37992a54ee68a9622e985e60c8e8f12d9f # v3.27.4
         with:
           languages: go
 
       - name: Perform CodeQL Analysis
-        uses: github/codeql-action/analyze@v3
+        uses: github/codeql-action/analyze@ea9e4e37992a54ee68a9622e985e60c8e8f12d9f # v3.27.4
 
   UnitTests:
     runs-on: ubuntu-latest
 
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
 
       - name: Install Go
-        uses: actions/setup-go@v5
+        uses: actions/setup-go@41dfa10bad2bb2ae585af6ee5bb4d7d973ad74ed # v5.1.0
         with:
           go-version: ${{ env.GO }}
 
       - name: Run Unit Tests
         run: go test -race -cover -coverprofile=coverage.out -covermode=atomic
 
       - name: Codecov
-        uses: codecov/codecov-action@v5.0.4
+        uses: codecov/codecov-action@985343d70564a82044c1b7fcb84c2fa05405c1a2 # v5.0.4
         with:
           file: ./coverage.out
 
@@ -61,15 +61,14 @@ jobs:
 
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
 
       - name: Install Go
-        uses: actions/setup-go@v5
+        uses: actions/setup-go@41dfa10bad2bb2ae585af6ee5bb4d7d973ad74ed # v5.1.0
         with:
           go-version: ${{ env.GO }}
 
       - name: Run GolangCi-Lint
-        uses: golangci/golangci-lint-action@v6.1.1
+        uses: golangci/golangci-lint-action@971e284b6050e8a5849b72094c50ab08da042db8 # v6.1.1
         with:
           version: latest
-          skip-build-cache: true
diff --git a/.github/workflows/release.yaml b/.github/workflows/release.yaml
@@ -19,10 +19,10 @@ jobs:
       DOCKER_CLI_EXPERIMENTAL: "enabled"
     steps:
       - name: Checkout code
-        uses: actions/checkout@v4
+        uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
 
       - name: Install Go
-        uses: actions/setup-go@v5
+        uses: actions/setup-go@41dfa10bad2bb2ae585af6ee5bb4d7d973ad74ed # v5.1.0
         with:
           go-version: ${{ env.GO }}
 
@@ -43,7 +43,7 @@ jobs:
           password: ${{ secrets.DOCKER_HUB_TOKEN }}
 
       - name: Run GoReleaser
-        uses: goreleaser/goreleaser-action@v6
+        uses: goreleaser/goreleaser-action@9ed2f89a662bf1735a48bc8557fd212fa902bebf # v6.1.0
         with:
           version: latest
           args: release --config .github/goreleaser-cli.yml
diff --git a/.golangci.yml b/.golangci.yml
@@ -5,14 +5,14 @@ linters:
   enable: # keep in ascending order
     - asciicheck
     - bodyclose
+    - copyloopvar
     - dupl
     - durationcheck
+    - err113
     - exhaustive
-    - exportloopref
     - gci
     - goconst
     - gocritic
-    - goerr113
     - gofumpt
     - goprintffuncname
     - gosec
@@ -41,7 +41,10 @@ linters-settings:
     disable:
       - shadow
   gci:
-    local-prefixes: github.com/sv-tools/mock-http-server
+    sections:
+      - standard
+      - default
+      - prefix(github.com/sv-tools/mock-http-server)
   gocognit:
     min-complexity: 15
   gocyclo:
diff --git a/README.md b/README.md
@@ -5,7 +5,23 @@
 
 A simple HTTP Server to be used for the unit or end-to-end or integrations tests.
 * yaml based configuration, see an [example config file](example_config.yaml).
-* docker image is published in this repo or docker hub
+* docker image is published in this repo and on the docker hub
+
+## Usage
+
+```shell
+docker run -p 8080:8080 -v $(pwd)/example_config.yaml:/config.yaml -e CONFIG=config.yaml ghcr.io/sv-tools/mock-http-server:latest
+```
+
+in second shell
+```shell
+curl http://localhost:8080/users -H"X-Request-Id: 123"
+> {"id":1,"name":"John","id":2,"name":"Jane"}
+
+curl http://localhost:8080/users/1 -H"X-Request-Id: 123"
+> {"id":1,"name":"John"}
+```
+
 
 ## License
 
diff --git a/config.go b/config.go
@@ -1,8 +1,11 @@
 package main
 
 import (
+	"bytes"
+	"fmt"
 	"net/http"
 	"os"
+	"text/template"
 
 	"golang.org/x/exp/slog"
 )
@@ -14,7 +17,6 @@ type Config struct {
 }
 
 type Route struct {
-	Method    string     `json:"method,omitempty" yaml:"method,omitempty"`
 	Pattern   string     `json:"pattern,omitempty" yaml:"pattern,omitempty"`
 	Responses []Response `json:"responses" yaml:"responses"`
 }
@@ -53,8 +55,12 @@ func responsesWriter(responses []Response, log *slog.Logger) http.HandlerFunc {
 					http.Error(writer, err.Error(), http.StatusInternalServerError)
 					return
 				}
-			} else if response.Body != "" {
-				data = []byte(response.Body)
+			} else if body := response.Body; body != "" {
+				var err error
+				data, err = executeTemplate(body, request)
+				if err != nil {
+					panic(err)
+				}
 			}
 
 			for name, header := range response.Headers {
@@ -71,10 +77,22 @@ func responsesWriter(responses []Response, log *slog.Logger) http.HandlerFunc {
 
 			if len(data) > 0 {
 				if _, err := writer.Write(data); err != nil {
-					log.Error("sending response failed", err)
+					log.ErrorContext(request.Context(), "sending response failed", slog.String("error", err.Error()))
 				}
 			}
 			return
 		}
 	}
 }
+
+func executeTemplate(body string, request *http.Request) ([]byte, error) {
+	tmpl, err := template.New("response").Parse(body)
+	if err != nil {
+		return nil, fmt.Errorf("parse template failed: %w", err)
+	}
+	buf := bytes.NewBuffer(nil)
+	if err := tmpl.Execute(buf, request); err != nil {
+		return nil, fmt.Errorf("execute template failed: %w", err)
+	}
+	return buf.Bytes(), nil
+}
diff --git a/config.schema.json b/config.schema.json
@@ -21,11 +21,6 @@
       "items": {
         "type": "object",
         "properties": {
-          "method": {
-            "description": "The HTTP method, any of the standard or custom.",
-            "default": "GET",
-            "type": "string"
-          },
           "pattern": {
             "description": "An url pattern",
             "default": "/",
diff --git a/example_config.yaml b/example_config.yaml
@@ -1,30 +1,46 @@
+request_id_header: "X-Request-ID" # to be logged if present in the request headers
 routes:
-  - method: get
-    pattern: /users
+  - pattern: GET /users # see https://go.dev/blog/routing-enhancements for more information about patterns
     responses:
-      - code: 200
+      - code: 200 # first 3 responses: 200 OK
         body: |
           [
             {
-              "name": "foo"
+              "id": 1,
+              "name": "John"
             },
             {
-              "name": "bar"
+              "id": 2,
+              "name": "Jane"
             }
           ]
         is_json: true
         repeat: 3
-      - code: 500
+      - code: 500 # 4th response: 500 Internal Server Error
         repeat: 1
         body: "something is broken"
-      - code: 200
+      - code: 200 # all other responses: 200 OK
         body: |
           [
             {
-              "name": "foo"
+              "id": 1,
+              "name": "John"
             },
             {
-              "name": "bar"
+              "id": 2,
+              "name": "Jane"
             }
           ]
         is_json: true
+  - pattern: GET /users/{id}
+    responses:
+      - code: 200
+        body: | # supports Go templates: https://pkg.go.dev/text/template
+          {
+            "id": "{{.PathValue "id"}}",
+            "name": "John"
+          }
+        is_json: true
+        repeat: 1
+      - code: 404
+        body: user "{{.PathValue "id"}}" not found
diff --git a/go.mod b/go.mod
@@ -3,8 +3,7 @@ module github.com/sv-tools/mock-http-server
 go 1.23.0
 
 require (
-	github.com/go-chi/chi/v5 v5.1.0
 	github.com/spf13/pflag v1.0.5
-	golang.org/x/exp v0.0.0-20240823005443-9b4947da3948
+	golang.org/x/exp v0.0.0-20241108190413-2d47ceb2692f
 	gopkg.in/yaml.v3 v3.0.1
 )
diff --git a/go.sum b/go.sum
@@ -1,9 +1,7 @@
-github.com/go-chi/chi/v5 v5.1.0 h1:acVI1TYaD+hhedDJ3r54HyA6sExp3HfXq7QWEEY/xMw=
-github.com/go-chi/chi/v5 v5.1.0/go.mod h1:DslCQbL2OYiznFReuXYUmQ2hGd1aDpCnlMNITLSKoi8=
 github.com/spf13/pflag v1.0.5 h1:iy+VFUOCP1a+8yFto/drg2CJ5u0yRoB7fZw3DKv/JXA=
 github.com/spf13/pflag v1.0.5/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An2Bg=
-golang.org/x/exp v0.0.0-20240823005443-9b4947da3948 h1:kx6Ds3MlpiUHKj7syVnbp57++8WpuKPcR5yjLBjvLEA=
-golang.org/x/exp v0.0.0-20240823005443-9b4947da3948/go.mod h1:akd2r19cwCdwSwWeIdzYQGa/EZZyqcOdwWiwj5L5eKQ=
+golang.org/x/exp v0.0.0-20241108190413-2d47ceb2692f h1:XdNn9LlyWAhLVp6P/i8QYBW+hlyhrhei9uErw2B5GJo=
+golang.org/x/exp v0.0.0-20241108190413-2d47ceb2692f/go.mod h1:D5SMRVC3C2/4+F/DB1wZsLRnSNimn2Sp/NPsCrsv8ak=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
diff --git a/log.go b/log.go
diff --git a/main.go b/main.go

Original file line number	Diff line number	Diff line change
`@@ -1,8 +1,11 @@`
`1`	`1`	`package main`
`2`	`2`
`3`	`3`	`import (`
	`4`	`+ "bytes"`
	`5`	`+ "fmt"`
`4`	`6`	`"net/http"`
`5`	`7`	`"os"`
	`8`	`+ "text/template"`
`6`	`9`
`7`	`10`	`"golang.org/x/exp/slog"`
`8`	`11`	`)`
`@@ -14,7 +17,6 @@ type Config struct {`
`14`	`17`	`}`
`15`	`18`
`16`	`19`	`type Route struct {`
`17`		- Method string `json:"method,omitempty" yaml:"method,omitempty"`
`18`	`20`	Pattern string `json:"pattern,omitempty" yaml:"pattern,omitempty"`
`19`	`21`	Responses []Response `json:"responses" yaml:"responses"`
`20`	`22`	`}`
`@@ -53,8 +55,12 @@ func responsesWriter(responses []Response, log *slog.Logger) http.HandlerFunc {`
`53`	`55`	`http.Error(writer, err.Error(), http.StatusInternalServerError)`
`54`	`56`	`return`
`55`	`57`	`}`
`56`		`- } else if response.Body != "" {`
`57`		`- data = []byte(response.Body)`
	`58`	`+ } else if body := response.Body; body != "" {`
	`59`	`+ var err error`
	`60`	`+ data, err = executeTemplate(body, request)`
	`61`	`+ if err != nil {`
	`62`	`+ panic(err)`
	`63`	`+ }`
`58`	`64`	`}`
`59`	`65`
`60`	`66`	`for name, header := range response.Headers {`
`@@ -71,10 +77,22 @@ func responsesWriter(responses []Response, log *slog.Logger) http.HandlerFunc {`
`71`	`77`
`72`	`78`	`if len(data) > 0 {`
`73`	`79`	`if _, err := writer.Write(data); err != nil {`
`74`		`- log.Error("sending response failed", err)`
	`80`	`+ log.ErrorContext(request.Context(), "sending response failed", slog.String("error", err.Error()))`
`75`	`81`	`}`
`76`	`82`	`}`
`77`	`83`	`return`
`78`	`84`	`}`
`79`	`85`	`}`
`80`	`86`	`}`
	`87`	`+`
	`88`	`+func executeTemplate(body string, request *http.Request) ([]byte, error) {`
	`89`	`+ tmpl, err := template.New("response").Parse(body)`
	`90`	`+ if err != nil {`
	`91`	`+ return nil, fmt.Errorf("parse template failed: %w", err)`
	`92`	`+ }`
	`93`	`+ buf := bytes.NewBuffer(nil)`
	`94`	`+ if err := tmpl.Execute(buf, request); err != nil {`
	`95`	`+ return nil, fmt.Errorf("execute template failed: %w", err)`
	`96`	`+ }`
	`97`	`+ return buf.Bytes(), nil`
	`98`	`+}`
Original file line number	Diff line number	Diff line change
`@@ -3,8 +3,7 @@ module github.com/sv-tools/mock-http-server`
`3`	`3`	`go 1.23.0`
`4`	`4`
`5`	`5`	`require (`
`6`		`- github.com/go-chi/chi/v5 v5.1.0`
`7`	`6`	`github.com/spf13/pflag v1.0.5`
`8`		`- golang.org/x/exp v0.0.0-20240823005443-9b4947da3948`
	`7`	`+ golang.org/x/exp v0.0.0-20241108190413-2d47ceb2692f`
`9`	`8`	`gopkg.in/yaml.v3 v3.0.1`
`10`	`9`	`)`