Unverified Commit 23cdff1d authored by Russell Cohen's avatar Russell Cohen Committed by GitHub
Browse files

Allow 'null' variants in unions (#3481) 

## Motivation and Context
- https://github.com/awslabs/aws-sdk-rust/issues/1095

## Description
Update the JSON parser generator to allow for `null` to be set in
unions. Servers can send unions like this:
```json
{
  "AmazonElasticsearchParameters": null,
  "AmazonOpenSearchParameters": null,
  "AppFlowParameters": null,
  "AthenaParameters": null,
  "AuroraParameters": null,
  "AuroraPostgreSqlParameters": null,
  "AwsIotAnalyticsParameters": null,
  "BigQueryParameters": null,
  "DatabricksParameters": null,
  "Db2Parameters": null,
  "DenodoParameters": null,
  "DocumentDBParameters": null,
  "DremioParameters": null,
  "ExasolParameters": null,
  "GoogleAnalyticsParameters": null,
  "JiraParameters": null,
  "MariaDbParameters": null,
  "MongoAtlasParameters": null,
  "MongoDBParameters": null,
  "MySqlParameters": null,
  "OracleParameters": null,
  "PostgreSqlParameters": null,
  "PrestoParameters": null,
  "RdsParameters": null,
  "RedshiftParameters": null,
  "S3Parameters": {
    "IsUploaded": false,
    "ManifestFileLocation": {
      "Bucket": "deided-bucket.prod.us-east-1",
      "Key": "sales/manifest.json"
    },
    "RoleArn": null
  },
  "SalesforceParameters": null,
  "SapHanaParameters": null,
  "ServiceNowParameters": null,
  "SnowflakeParameters": null,
  "SparkParameters": null,
  "SqlServerParameters": null,
  "StarburstParameters": null,
  "TeradataParameters": null,
  "TrinoParameters": null,
  "TwitterParameters": null
}
```

This caused our parser to fail.

## Testing
<!--- Please describe in detail how you tested your changes -->
<!--- Include details of your testing environment, and the tests you ran
to -->
<!--- see how your change affects other areas of the code, etc. -->
- [x] New unit test
- [x] Dry run against new [smithy protocol
test](https://github.com/smithy-lang/smithy/pull/2180)

## Checklist
<!--- If a checkbox below is not applicable, then please DELETE it
rather than leaving it unchecked -->
- [ ] I have updated `CHANGELOG.next.toml` if I made changes to the
smithy-rs codegen or runtime crates
- [ ] I have updated `CHANGELOG.next.toml` if I made changes to the AWS
SDK, generated SDK code, or SDK runtime crates

----

_By submitting this pull request, I confirm that you can use, modify,
copy, and redistribute this contribution, under the terms of your
choice._
parent 0b35a092

build.gradle.kts

+4 −1
Original line number Diff line number Diff line
@@ -15,8 +15,11 @@ buildscript { 
}



allprojects {

    val allowLocalDeps: String by project

    repositories {

        // mavenLocal()

        if (allowLocalDeps.toBoolean()) {

         mavenLocal()

        }

        mavenCentral()

        google()

    }

buildSrc/build.gradle.kts

+0 −1
Original line number Diff line number Diff line
@@ -12,7 +12,6 @@ plugins { 
repositories {

    mavenCentral()

    google()

    /* mavenLocal() */

}



// Load properties manually to avoid hard coding smithy version

codegen-client-test/build.gradle.kts

+0 −2
Original line number Diff line number Diff line
@@ -114,8 +114,6 @@ val allCodegenTests = listOf( 
    ),

    ClientTest("aws.protocoltests.misc#QueryCompatService", "query-compat-test", dependsOn = listOf("aws-json-query-compat.smithy")),

).map(ClientTest::toCodegenTest)

// use this line to run just one test

// .filter { it.module == "query-compat-test" }



project.registerGenerateSmithyBuildTask(rootProject, pluginName, allCodegenTests)

project.registerGenerateCargoWorkspaceTask(rootProject, pluginName, allCodegenTests, workingDirUnderBuildDir)

codegen-core/src/main/kotlin/software/amazon/smithy/rust/codegen/core/smithy/protocols/parse/JsonParserGenerator.kt

+21 −0
Original line number Diff line number Diff line
@@ -36,6 +36,7 @@ import software.amazon.smithy.rust.codegen.core.rustlang.withBlockTemplate 
import software.amazon.smithy.rust.codegen.core.smithy.CodegenContext

import software.amazon.smithy.rust.codegen.core.smithy.CodegenTarget

import software.amazon.smithy.rust.codegen.core.smithy.RuntimeType

import software.amazon.smithy.rust.codegen.core.smithy.RuntimeType.Companion.preludeScope

import software.amazon.smithy.rust.codegen.core.smithy.canUseDefault

import software.amazon.smithy.rust.codegen.core.smithy.customize.NamedCustomization

import software.amazon.smithy.rust.codegen.core.smithy.customize.Section
@@ -121,6 +122,7 @@ class JsonParserGenerator( 
            "skip_to_end" to smithyJson.resolve("deserialize::token::skip_to_end"),

            "Token" to smithyJson.resolve("deserialize::Token"),

            "or_empty" to orEmptyJson(),

            *preludeScope,

        )



    /**
@@ -560,6 +562,15 @@ class JsonParserGenerator( 
                            *codegenScope,

                        ) {

                            objectKeyLoop(hasMembers = shape.members().isNotEmpty()) {

                                rustTemplate(

                                    """

                                    if let #{Some}(#{Ok}(#{Token}::ValueNull { .. })) = tokens.peek() {

                                        let _ = tokens.next().expect("peek returned a token")?;

                                        continue;

                                    }

                                    """,

                                    *codegenScope,

                                )

                                rustTemplate(

                                    """

                                    let key = key.to_unescaped()?;
@@ -622,6 +633,16 @@ class JsonParserGenerator( 
                            *codegenScope,

                        )

                    }

                    // If we've gotten to the point where the union had a `{ ... }` section, we can't return None

                    // anymore. If we didn't parse a union at this point, this is an error.

                    rustTemplate(

                        """

                        if variant.is_none() {

                            return Err(#{Error}::custom("Union did not contain a valid variant."))

                        }

                        """,

                        *codegenScope,

                    )

                    rust("Ok(variant)")

                }

            }

codegen-core/src/test/kotlin/software/amazon/smithy/rust/codegen/core/smithy/protocols/parse/JsonParserGeneratorTest.kt

+20 −0
Original line number Diff line number Diff line
@@ -183,6 +183,26 @@ class JsonParserGeneratorTest { 
                """,

            )



            unitTest(

                "allow_null_for_variants",

                """

                // __type field should be ignored during deserialization

                let input = br#"{ "top": { "choice": { "blob": null, "boolean": null, "int": 5, "long": null, "__type": "value-should-be-ignored-anyway" } } }"#;

                let output = ${format(operationGenerator)}(input, test_output::OpOutput::builder()).unwrap().build();

                use test_model::Choice;

                assert_eq!(Choice::Int(5), output.top.unwrap().choice);

                """,

            )



            unitTest(

                "all_variants_null",

                """

                // __type field should be ignored during deserialization

                let input = br#"{ "top": { "choice": { "blob": null, "boolean": null, "int": null, "long": null, "__type": "value-should-be-ignored-anyway" } } }"#;

                let _err = ${format(operationGenerator)}(input, test_output::OpOutput::builder()).expect_err("invalid union");

                """,

            )



            unitTest(

                "empty_error",

                """