I have a test function using ic-test-state-machine: pub fn suggections( env: &StateMachine, canister_id: Principal, offset: Option , limit: Option , ) -> Result , ic_test_state_machine_client::CallError> { let res: Result ,), CallError> = query_candid(env, canister_id, "suggections", (offset, limit)); assert!(res.is_ok(), "should okkkkkkkkkkkkkkk pls"); res.map(|r| r.0) } Here is my Suggection’s definition, it had implment CandidType: #[derive( Queryable, Debug, CandidType, Serialize, Deserialize, Selectable, Insertable, Default, Clone, Identifiable, PartialEq, )] #[diesel(primary_key(id))] #[diesel(table_name = crate::schema::suggections)] #[diesel(check_for_backend(diesel::sqlite::Sqlite))] pub struct Suggection { pub id: i32, pub title: String, pub content: Option , pub principal: String, pub created_at: time::OffsetDateTime, } The time::OffsetDateTime also implmented CandidType: #[cfg(feature = "icp")] impl CandidType for OffsetDateTime { fn _ty() -> Type { Type::Nat } fn idl_serialize (&self, serializer: S) -> Result where S: Serializer, { let res = self.unix_timestamp_nanos(); let res: u128 = res.abs().try_into().unwrap(); let nat = candid::Nat::from(res); let res = serializer.serialize_nat(&nat); res } } But when i run cargo test --package suggection_box --target x86_64-unknown-linux-musl -- --nocapture I got: thread 'get_suggections_should_work' panicked at 'Failed to decode response as candid type (alloc::vec::Vec ,): error: Fail to decode argument 0 from table0 to vec record { id : int32; title : text; "principal" : text; content : opt text; created_at : nat; } bytes: [68, 73, 68, 76, 3, 109, 1, 108, 5, 219, 183, 1, 117, 152, 171, 236, 129, 1, 113, 174, 157, 177, 144, 1, 113, 185, 154, 222, 203, 1, 2, 170, 172, 217, 208, 6, 125, 110, 113, 1, 0, 1, 1, 0, 0, 0, 7, 116, 105, 116, 108, 101, 95, 49, 63, 115, 54, 109, 53, 119, 45, 117, 51, 55, 99, 107, 45, 119, 102, 121, 52, 102, 45, 120, 103, 108, 108, 116, 45, 106, 101, 114, 104, 117, 45, 97, 120, 51, 51, 109, 45, 102, 114, 110, 53, 115, 45, 115, 97, 114, 105, 53, 45, 115, 106, 99, 53, 100, 45, 55, 108, 55, 97, 110, 45, 120, 97, 101, 1, 9, 99, 111, 110, 116, 101, 110, 116, 95, 50, 128, 160, 240, 150, 224, 181, 240, 2] utf8: DIDLml۷u��q��q��}nqtitl

[image] Candid failed to decode for internal error Developers We need to implment our own Deserializer in this situation: pub struct Suggection { pub id: i32, pub title: String, pub content: Option , pub principal: String, #[serde(with = "timestamp_format")] pub created_at: time::OffsetDateTime, } mod timestamp_format { use candid::Deserialize; use serde:de:Error as SerdeError; use serde::{Deserializer, Serializer}; use time::PrimitiveDateTime; use time::{Duration, OffsetDateTime}; pub fn deserial…

Compiled successful. And deploy canister to local, dfx call canister works: root@DESKTOP-D2P8H7D:# dfx canister call suggection_box suggections ( vec { record { id = 1 : int32; title = "title"; "principal" = "****************************************"; content = null; created_at = 1_687_677_000_000_000 : nat; }; }, )

I am new to rust. I seem that the candid’s decode_args in with_candid function /// A helper function that we use to implement both [`call_candid`] and /// [`query_candid`]. pub fn with_candid ( input: Input, f: impl FnOnce(Vec ) -> Result , ) -> Result where Input: ArgumentEncoder, Output: for ArgumentDecoder , { let in_bytes = encode_args(input).expect("failed to encode args"); match f(in_bytes) { Ok(WasmResult::Reply(out_bytes)) => Ok(decode_args(&out_bytes).unwrap_or_else(|e| { panic!( "Failed to decode response as candid type {}:\nerror: {}\nbytes: {:?}\nutf8: {}", std::any::type_name:: (), e, out_bytes, String::from_utf8_lossy(&out_bytes), ) })), Ok(WasmResult::Reject(message)) => Err(CallError::Reject(message)), Err(user_error) => Err(CallError::UserError(user_error)), } } can not find the CandidType implmentation in time crate for time::OffsetDateTime struct.

Similar test: #[test] fn test_candid_decode() { let vecc: Vec = vec![ 68, 73, 68, 76, 3, 109, 1, 108, 5, 219, 183, 1, 117, 152, 171, 236, 129, 1, 113, 174, 157, 177, 144, 1, 113, 185, 154, 222, 203, 1, 2, 170, 172, 217, 208, 6, 125, 110, 113, 1, 0, 1, 1, 0, 0, 0, 7, 116, 105, 116, 108, 101, 95, 49, 63, 115, 54, 109, 53, 119, 45, 117, 51, 55, 99, 107, 45, 119, 102, 121, 52, 102, 45, 120, 103, 108, 108, 116, 45, 106, 101, 114, 104, 117, 45, 97, 120, 51, 51, 109, 45, 102, 114, 110, 53, 115, 45, 115, 97, 114, 105, 53, 45, 115, 106, 99, 53, 100, 45, 55, 108, 55, 97, 110, 45, 120, 97, 101, 1, 9, 99, 111, 110, 116, 101, 110, 116, 95, 50, 128, 160, 240, 150, 224, 181, 240, 2, ]; let res: Result ,), candid::Error> = candid::decode_args(&vecc); println!("test_candid_decode: {:?}", res); assert!(res.is_ok()); } run cargo test --package suggection_box --target x86_64-unknown-linux-musl -- --nocapture and got: running 4 tests test_candid_decode: Err(Custom(Fail to decode argument 0 from table0 to vec record { id : int32; title : text; "principal" : text; content : opt text; created_at : nat; } Caused by: 0: input: 4449444c036d016c05dbb7017598abec810171ae9db1900171b99adecb0102aaacd9d0067d6e7101000101000000077469746c655f313f73366d35772d753337636b2d77667934662d78676c6c742d6a657268752d617833336d2d66726e35732d73617269352d736a6335642d376c37616e2d7861650109636f6e74656e745f32_80a0f096e0b5f002 table: type table0 = vec table1 type table1 = record { 23_515 : int32; 272_307_608 : text; 302_796_462 : text; 427_265_337 : table2; 1_779_848_746 : nat; } type table2 = opt text wire_type: nat, expect_type: nat 1: Internal error at /root/.cargo/registry/src/index.crates.io-6f17d22bba15001f/candid-0.8.4/src/de.rs:548. Please file a bug.

This works: #[derive(CandidType, Debug, Serialize, Deserialize)] pub struct Suggection2 { pub id: i32, pub title: String, pub content: Option , pub principal: String, pub created_at: u128, } #[test] fn test_candid_decode() { let vecc: Vec = vec![ 68, 73, 68, 76, 3, 109, 1, 108, 5, 219, 183, 1, 117, 152, 171, 236, 129, 1, 113, 174, 157, 177, 144, 1, 113, 185, 154, 222, 203, 1, 2, 170, 172, 217, 208, 6, 125, 110, 113, 1, 0, 1, 1, 0, 0, 0, 7, 116, 105, 116, 108, 101, 95, 49, 63, 115, 54, 109, 53, 119, 45, 117, 51, 55, 99, 107, 45, 119, 102, 121, 52, 102, 45, 120, 103, 108, 108, 116, 45, 106, 101, 114, 104, 117, 45, 97, 120, 51, 51, 109, 45, 102, 114, 110, 53, 115, 45, 115, 97, 114, 105, 53, 45, 115, 106, 99, 53, 100, 45, 55, 108, 55, 97, 110, 45, 120, 97, 101, 1, 9, 99, 111, 110, 116, 101, 110, 116, 95, 50, 128, 160, 240, 150, 224, 181, 240, 2, ]; let res: Result ,), candid::Error> = candid::decode_args(&vecc); println!("test_candid_decode: {:?}", res); assert!(res.is_ok()); }

`ic-test-state-machine` failed to decode response as candid type

Developers

famouscat8 June 25, 2023, 10:59am 6

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`ic-test-state-machine` failed to decode response as candid type

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