chore: support debugging by attaching devnet process

This commit helps user to debug a process which is run by docker
compose. Currently, this only works on Linux. There should be another
way for macOS users.

Resolves: #11

.vscode/launch.json

@@ -0,0 +1,22 @@
+{
+  "version": "0.2.0",
+  "configurations": [
+    {
+      "name": "Attach to devnet process",
+      "type": "go",
+      "request": "attach",
+      "mode": "local",
+      "processId": "${command:pickGoProcess}",
+      "substitutePath": [
+        {
+          "from":"${workspaceFolder}",
+          "to": "/app"
+        },
+        {
+          "from": "${env:GOPATH}",
+          "to": "/go"
+        }
+      ]
+    },
+  ]
+}

Dockerfile

@@ -13,22 +13,45 @@ COPY ./.git /app/.git
 WORKDIR /app
 RUN make build
 
+FROM alpine:3.17 as runner
+
+RUN addgroup user && \
+    adduser -G user -s /bin/sh -h /home/user -D user
+
+USER user
+WORKDIR /home/user/
+
+FROM alpine:3.17 as runner-with-kanvas-log
+
+RUN addgroup user && \
+    adduser -G user -s /bin/sh -h /home/user -D user
+
+RUN mkdir /kanvas_log/ && \
+    chown user:user /kanvas_log
+
+USER user
+WORKDIR /home/user/
+
 # Node
-FROM alpine:3.17 as kanvas-node
+FROM runner-with-kanvas-log as kanvas-node
 COPY --from=builder /app/bin/kanvas-node /usr/local/bin
+
 ENTRYPOINT ["kanvas-node"]
 
 # Stateviz
-FROM alpine:3.17 as kanvas-stateviz
+FROM runner-with-kanvas-log as kanvas-stateviz
 COPY --from=builder /app/bin/kanvas-stateviz /usr/local/bin
+
 CMD ["kanvas-stateviz"]
 
 # Batcher
-FROM alpine:3.17 as kanvas-batcher
+FROM runner as kanvas-batcher
 COPY --from=builder /app/bin/kanvas-batcher /usr/local/bin
+
 ENTRYPOINT ["kanvas-batcher"]
 
 # Validator
-FROM alpine:3.17 as kanvas-validator
+FROM runner as kanvas-validator
 COPY --from=builder /app/bin/kanvas-validator /usr/local/bin
+
 ENTRYPOINT ["kanvas-validator"]

ops-devnet/docker-compose.yml

@@ -12,6 +12,7 @@ volumes:
 
 services:
   l1:
+    pid: host # allow debugging
     image: ethereum/client-go:v1.10.22
     ports:
       - "8545:8545"
@@ -28,6 +29,7 @@ services:
       - "/entrypoint.sh"
 
   l2:
+    pid: host # allow debugging
     image: wemixkanvas/geth:dev-6ec404a78abc
     ports:
       - "9545:8545"
@@ -45,6 +47,7 @@ services:
       - "--authrpc.jwtsecret=/config/test-jwt-secret.txt"
 
   kanvas-node:
+    pid: host # allow debugging
     depends_on:
       - l1
       - l2
@@ -86,6 +89,7 @@ services:
       - kanvas_log:/kanvas_log
 
   kanvas-validator:
+    pid: host # allow debugging
     depends_on:
       - l1
       - l2
@@ -115,6 +119,7 @@ services:
       VALIDATOR_CHALLENGER_DISABLED: "true"
 
   kanvas-challenger:
+    pid: host # allow debugging
     depends_on:
       - l1
       - l2
@@ -138,6 +143,7 @@ services:
       VALIDATOR_OUTPUT_SUBMITTER_DISABLED: "true"
 
   kanvas-batcher:
+    pid: host # allow debugging
     depends_on:
       - l1
       - l2
@@ -169,6 +175,7 @@ services:
       BATCHER_METRICS_ENABLED: "true"
 
   stateviz:
+    pid: host # allow debugging
     build:
       context: ..
       target: "kanvas-stateviz"

specs/meta/devnet.md

@@ -6,6 +6,7 @@
 **Table of Contents**
 
 - [Local Devnet Setup](#local-devnet-setup)
+  - [Debugging VS Code](#debugging-vs-code)
 
 <!-- END doctoc generated TOC please keep comment here to allow auto update -->
 
@@ -51,3 +52,17 @@ The batch submitter uses the account below to submit batches to L1:
 
 - Address: `0xde3829a23df1479438622a08a116e8eb3f620bb5`
 - Private key: `bf7604d9d3a1c7748642b1b7b05c2bd219c9faa91458b370f85e5a40f3b03af7`
+
+## Debugging VS Code
+
+We added a debugging configuration called 'Attach to devnet process' to .vscode/launch.json. Therefore, on Linux, you
+can use VS Code to attach to the devnet process and perform debugging as shown in the figure below.
+
+![vscode_debug](../asset/../assets/vscode_debug.png)
+
+You might need to disable linux ptrace protection.
+
+```shell
+> sudo su
+> echo 0 > /proc/sys/kernel/yama/ptrace_scope
+```