wip: expose endpoint to query smart rollup parameter json schema

Tzkt.Api/Controllers/SmartRollupsController.cs

@@ -92,6 +92,27 @@ public async Task<ActionResult<SmartRollup>> GetSmartRollup([Address] string add
             return this.Bytes(res);
         }
 
+        /// <summary>
+        /// Get JSON Schema [2020-12] interface for the smart rollup
+        /// </summary>
+        /// <remarks>
+        /// Returns standard JSON Schema for smart rollup parameter.
+        /// </remarks>
+        /// <param name="address">Smart rollup address</param>
+        /// <returns></returns>
+        [HttpGet("{address}/interface")]
+        public async Task<ActionResult<ContractInterface>> GetInterface([Required][Address] string address)
+        {
+            var query = ResponseCacheService.BuildKey(Request.Path.Value);
+
+            if (ResponseCache.TryGet(query, out var cached))
+                return this.Bytes(cached);
+
+            var res = await SmartRollups.GetSmartRollupInterface(address);
+            cached = ResponseCache.Set(query, res);
+            return this.Bytes(cached);
+        }
+
         /// <summary>
         /// Get smart rollup stakers
         /// </summary>

Tzkt.Api/Repositories/SmartRollupsRepository.cs

@@ -1,6 +1,7 @@
 using System.Data;
 using Dapper;
 using Netezos.Encoding;
+using Netezos.Contracts;
 using Tzkt.Api.Models;
 using Tzkt.Api.Services.Cache;
 
@@ -205,6 +206,26 @@ public async Task<SmartRollup> GetSmartRollup(string address)
             };
         }
 
+        public async Task<RawJson> GetSmartRollupInterface(string address)
+        {
+            var rawAccount = await Accounts.GetAsync(address);
+            if (rawAccount is not RawSmartRollup rollup)
+                return null;
+
+            using var db = GetConnection();
+
+            var parameterType = await db.QueryFirstOrDefaultAsync($@"
+                SELECT      ""ParameterType""
+                FROM        ""SmartRollupOriginateOps""
+                WHERE       ""SmartRollupId"" = {rollup.Id}
+                LIMIT       1"
+            );
+            if (parameterType is not byte[] bytes)
+                return null;
+
+            return Schema.Create(Micheline.FromBytes(bytes) as MichelinePrim).GetJsonSchema();
+        }
+
         public async Task<IEnumerable<SmartRollup>> GetSmartRollups(SrFilter filter, Pagination pagination)
         {
             var rows = await QuerySmartRollupsAsync(filter, pagination);