feat: initial work on the flask app

examples/flask/app.py

@@ -0,0 +1,111 @@
+# -*- coding: utf-8 -*-
+import functools
+
+from flask import Flask, jsonify, make_response, request
+from flask_cors import CORS
+from solana.rpc.api import Client
+from solana.transaction import Instruction, Transaction
+from solders.compute_budget import set_compute_unit_price
+from solders.instruction import AccountMeta
+from solders.pubkey import Pubkey
+
+from solana_actions.constants import (
+    ACTIONS_CORS_HEADERS,
+    MEMO_PROGRAM_ID,
+)
+from solana_actions.create_post_response import (
+    CreateActionPostResponseArgs,
+    create_post_response,
+)
+from solana_actions.types import ActionPostResponse
+
+SOLANA_API = "https://api.devnet.solana.com"
+
+
+app = Flask(__name__)
+CORS(app, resources={r"/api/*": {"origins": "*"}})
+
+
+def return_json(f):
+    @functools.wraps(f)
+    def inner(**kwargs):
+        ret = f(**kwargs)
+        response = make_response(jsonify(ret))
+        response.headers.update(ACTIONS_CORS_HEADERS)
+        response.content_type = "application/json"
+        response.status_code = 200
+        return response
+
+    return inner
+
+
+@app.route("/actions.json", methods=["GET", "OPTIONS"])
+@return_json
+def actions_json():
+    return {
+        "rules": [
+            # map all root level routes to an action
+            {
+                "pathPattern": "/*",
+                "apiPath": "/api/actions/*",
+            },
+            # idempotent rule as the fallback
+            {
+                "pathPattern": "/api/actions/**",
+                "apiPath": "/api/actions/**",
+            },
+        ],
+    }
+
+
+@app.route("/api/actions/memo", methods=["GET", "OPTIONS"])
+@return_json
+def get_actions_memo():
+    return {
+        "title": "Actions Example - Simple On-chain Memo",
+        "icon": "/solana_devs.jpg",
+        "description": "Send a message on-chain using a Memo",
+        "label": "Send Memo",
+    }
+
+
+@app.route("/api/actions/memo", methods=["POST"])
+@return_json
+def post_actions_memo():
+    body = request.get_json(force=True)
+    # FIXME: add some validation to body!
+
+    account = Pubkey.from_string(body["account"])
+    # FIXME: do some basic validation and exception handling
+
+    connection = Client(SOLANA_API)
+    latest_block_hash = connection.get_latest_blockhash()
+    transaction = Transaction(
+        recent_blockhash=latest_block_hash.value.blockhash, fee_payer=account
+    ).add(
+        set_compute_unit_price(
+            micro_lamports=1000,
+        ),
+        Instruction(
+            program_id=Pubkey.from_string(MEMO_PROGRAM_ID),
+            data=b"this is a simple memo message2",
+            accounts=[AccountMeta(account, is_signer=True, is_writable=True)],
+        ),
+    )
+
+    actions_args: ActionPostResponse = ActionPostResponse(
+        transaction=transaction,
+        message="Post this memo on-chain",
+    )
+    payload: ActionPostResponse = create_post_response(
+        args=CreateActionPostResponseArgs(
+            fields=actions_args,
+            # no additional signers are required for this transaction
+            signers=None,
+        )
+    )
+    return payload.model_dump()
+
+
+if __name__ == "__main__":
+    app.run(port=5000)