Go Modules migration

.devcontainer/Dockerfile

 # Update the VARIANT arg in devcontainer.json to pick an Go version
-ARG VARIANT=1
+ARG VARIANT=1.14
 FROM golang:${VARIANT}
 
 # This Dockerfile adds a non-root user with sudo access. Update the “remoteUser” property in
@@ -27,17 +27,17 @@ RUN apt-get update \
     && rm -rf /var/lib/apt/lists/*
 
 # Install Go tools
+
+ENV GO111MODULE=on
+
 ARG GO_TOOLS_WITH_MODULES="\
     golang.org/x/tools/gopls \
     honnef.co/go/tools/... \
     golang.org/x/tools/cmd/gorename \
     golang.org/x/tools/cmd/goimports \
     golang.org/x/tools/cmd/guru \
-    golang.org/x/lint/golint \
-    github.com/mdempsky/gocode \
     github.com/cweill/gotests/... \
     github.com/haya14busa/goplay/cmd/goplay \
-    github.com/sqs/goreturns \
     github.com/josharian/impl \
     github.com/davidrjenni/reftools/cmd/fillstruct \
     github.com/uudashr/gopkgs/v2/cmd/gopkgs \
@@ -49,29 +49,13 @@ ARG GO_TOOLS_WITH_MODULES="\
     github.com/fatih/gomodifytags \
     github.com/mgechev/revive \
     github.com/go-delve/delve/cmd/dlv"
-RUN mkdir -p /tmp/gotools \
-    && cd /tmp/gotools \
-    && export GOPATH=/tmp/gotools \
-    # Go tools w/module support
-    && export GO111MODULE=on \
-    && (echo "${GO_TOOLS_WITH_MODULES}" | xargs -n 1 go get -x )2>&1 \
-    # gocode-gomod
-    && export GO111MODULE=auto \
-    && go get -x -d github.com/stamblerre/gocode 2>&1 \
-    && go build -o gocode-gomod github.com/stamblerre/gocode \
+
+RUN (echo "${GO_TOOLS_WITH_MODULES}" | xargs -n 1 go get )2>&1 \
     # golangci-lint
     && curl -sSfL https://raw.githubusercontent.com/golangci/golangci-lint/master/install.sh | sh -s -- -b /usr/local/bin 2>&1 \
-    # Move Go tools into path and clean up
-    && mv /tmp/gotools/bin/* /usr/local/bin/ \
-    && mv gocode-gomod /usr/local/bin/ \
-    && rm -rf /tmp/gotools
-
-ENV GO111MODULE=auto
-
 # [Optional] Uncomment the next line to use go get to install anything else you need
 # RUN go get -x <your-dependency-or-tool>
-
 # [Optional] Uncomment this section to install additional OS packages.
 # RUN apt-get update \
 #     && export DEBIAN_FRONTEND=noninteractive \
-#     && apt-get -y install --no-install-recommends <your-package-list-here>
\ No newline at end of file
+#     && apt-get -y install --no-install-recommends <your-package-list-here>

.devcontainer/devcontainer.json

 {
-	"name": "Go",
-	"build": {
-		"dockerfile": "Dockerfile",
-		// Update the VARIANT arg to pick a version of Go
-		"args": { "VARIANT": "1" }
-	},
-	"runArgs": [ "--cap-add=SYS_PTRACE", "--security-opt", "seccomp=unconfined" ],
+  "name": "Go",
+  "build": {
+    "dockerfile": "Dockerfile",
+    // Update the VARIANT arg to pick a version of Go
+    "args": { "VARIANT": "1.14" }
+  },
+  "runArgs": ["--cap-add=SYS_PTRACE", "--security-opt", "seccomp=unconfined"],
 
-	// Set *default* container specific settings.json values on container create.
-	"settings": { 
-		"terminal.integrated.shell.linux": "/bin/bash",
-		"go.gopath": "/go",
-		"go.inferGopath": true,
-		"go.useLanguageServer": true
-	},
-	
-	// Add the IDs of extensions you want installed when the container is created.
-	"extensions": [
-		"golang.Go"
-	],
+  // Set *default* container specific settings.json values on container create.
+  "settings": {
+    "terminal.integrated.shell.linux": "/bin/bash",
+    "go.useLanguageServer": true,
+    "[go]": {
+      "editor.formatOnSave": true,
+      "editor.codeActionsOnSave": {
+        "source.organizeImports": true
+      },
+      // Optional: Disable snippets, as they conflict with completion ranking.
+      "editor.snippetSuggestions": "none"
+    },
+    "[go.mod]": {
+      "editor.formatOnSave": true,
+      "editor.codeActionsOnSave": {
+        "source.organizeImports": true
+      }
+    },
+    "gopls": {
+      // Add parameter placeholders when completing a function.
+			"usePlaceholders": true,
+			// the completion engine is allowed to make suggestions for packages that you do not currently import.
+			"completeUnimported": true,
 
-	// Use 'forwardPorts' to make a list of ports inside the container available locally.
-	"forwardPorts": [9000],
+      // If true, enable additional analyses with staticcheck.
+      // Warning: This will significantly increase memory usage.
+      "staticcheck": true
+    },
+    "go.lintTool": "golangci-lint"
+  },
 
-	// Use 'postCreateCommand' to run commands after the container is created.
-	// "postCreateCommand": "go version",
+  // Add the IDs of extensions you want installed when the container is created.
+  "extensions": ["golang.Go"],
 
-	// Uncomment to connect as a non-root user. See https://aka.ms/vscode-remote/containers/non-root.
-	"remoteUser": "vscode"
-}
\ No newline at end of file
+  // Use 'forwardPorts' to make a list of ports inside the container available locally.
+  "forwardPorts": [9000],
+
+  // Use 'postCreateCommand' to run commands after the container is created.
+  // "postCreateCommand": "go version",
+
+  // Uncomment to connect as a non-root user. See https://aka.ms/vscode-remote/containers/non-root.
+  "remoteUser": "vscode"
+}

.vscode/launch.json

@@ -6,7 +6,7 @@
             "type": "go",
             "request": "launch",
             "mode": "debug",
-            "program": "${workspaceFolder}/src/main/server.go"
+            "program": "${workspaceFolder}/server.go"
         }
     ]
-}
\ No newline at end of file
+}

.vscode/settings.json

 {
     "go.useLanguageServer": true,
-    "go.inferGopath": true
-}
\ No newline at end of file
+    "go.inferGopath": false
+}