evictFromApiCache type definition seems inaccurate

[robokozo]

The type definition provided for the evictFromApiCache parameter of keyValuePair (keyValuePair: Record<string, string>) doesn't seem correct. It doesn't seem to match a scenario where it works but adhering to the schema does not work

//@aws-appsync/utils/lib/index.d.ts    
evictFromApiCache(typeName: string, fieldName: string, keyValuePair: Record<string, string>): void;

Example

try it yourself in the aws console, all the parts needed are below

Cache Configuration

{
  cachingConfig: {
    ttl: Duration.hours(1),
    cachingKeys: ["$context.arguments"]
  }
}

Cached Query

export function response(ctx) {
    const nextToken = ctx.arguments.nextToken;
    const timestamp = util.time.nowISO8601();
    
    if (nextToken == null) {
        return [
            { id: "1", title: "AllNull-A", content: `AN-AAA @ ${timestamp}` },
            { id: "2", title: "AllNull-B", content: `AN-BBB @ ${timestamp}` }
        ];
    }
    
    return [
        { id: "80", title: "NextToken-A", content: `NT-AAA @ ${timestamp}` },
        { id: "81", title: "NextToken-B", content: `NT-BBB @ ${timestamp}` }
    ];
}

Mutation that manually evicts the cache

export function response(ctx) {
    const argsString = JSON.stringify(ctx.arguments); //has to be a string due to signature
    
    extensions.evictFromApiCache("Query", "postList", {
        "$context.arguments": argsString
    });
    
    // Return debug info
    return {
        args: argsString,
        success: true
    };
}

Testing Queries and Mutations

# ===== QUERIES =====

query NextTokenOmitted {
  nextTokenOmitted: postList {
    id
    title
    content
  }
}

query NextTokenWithValue($nextTokenValue: String!) {
  nextTokenWithValue: postList(nextToken: $nextTokenValue) {
    id
    title
    content
  }
}

query NextTokenNull($nextTokenNull: String) {
  nextTokenNull: postList(nextToken: $nextTokenNull) {
    id
    title
    content
  }
}

query BothWithValue($nextTokenBothValue: String!, $limitBothValue: Int!) {
  bothWithValue: postList(nextToken: $nextTokenBothValue, limit: $limitBothValue) {
    id
    title
    content
  }
}

# ===== MUTATIONS =====

mutation EvictNextTokenOmitted {
  evictNextTokenOmitted: bustCache {
    args
    keys
    success
  }
}

mutation EvictNextTokenWithValue($evictNextTokenValue: String!) {
  evictNextTokenWithValue: bustCache(nextToken: $evictNextTokenValue) {
    args
    keys
    success
  }
}

mutation EvictNextTokenNull($evictNextTokenNull: String) { 
  evictNextTokenNull: bustCache(nextToken: $evictNextTokenNull) {
    args
    keys
    success
  }
}

mutation EvictBothWithValue($evictNextTokenBothValue: String!, $evictLimitBothValue: Int!) {
  evictBothWithValue: bustCache(nextToken: $evictNextTokenBothValue, limit: $evictLimitBothValue) {
    args
    keys
    success
  }
}

Variables used for testing

{
  "nextTokenValue": "abc123",
  "nextTokenNull": null,
  "nextTokenBothValue": "abc123",
  "limitBothValue": 10,
  "evictNextTokenValue": "abc123",
  "evictNextTokenNull": null,
  "evictNextTokenBothValue": "abc123",
  "evictLimitBothValue": 10
}

Results

When running each of the queries and corresponding mutations I get the appropriate response

{
  "extensions": {
    "apiCacheEntriesDeleted": 1
  },
  "data": { ... }
}

Except for evictBothWithValue

{
  "data": {
    "evictBothWithValue": {
      "args": "{\"nextToken\":\"abc123\",\"limit\":10}",
      "success": true
    }
  }
}

However, if I violate the TS type and just use ctx.arguments it works correctly for all cases

    extensions.evictFromApiCache("Query", "postList", {
        "$context.arguments": ctx.arguments
    });

{
  "extensions": {
    "apiCacheEntriesDeleted": 1
  },
  "data": {
    "evictBothWithValue": {
      "args": "{\"nextToken\":\"abc123\",\"limit\":10}",
      "success": true
    }
  }
}

Maybe this is a bug in the ts type or its an evictFromApiCache bug.

Note

If evicting with an empty object both forms work as expected

    extensions.evictFromApiCache("Query", "postList", {
        "$context.arguments": {}
    });
    // 
    extensions.evictFromApiCache("Query", "postList", {
        "$context.arguments": JSON.stringify({ }) //"{ }"
    });