private String generateHttpHeaderValue()

in codegen/smithy-go-codegen/src/main/java/software/amazon/smithy/go/codegen/integration/HttpBindingProtocolGenerator.java [1189:1321]
129 lines of code
24 McCabe index (conditional complexity)

    private String generateHttpHeaderValue(
            GenerationContext context,
            GoWriter writer,
            MemberShape memberShape,
            HttpBinding binding,
            String operand
    ) {
        Shape targetShape = context.getModel().expectShape(memberShape.getTarget());

        if (targetShape.getType() != ShapeType.LIST && targetShape.getType() != ShapeType.SET) {
            writer.addUseImports(SmithyGoDependency.STRINGS);
            writer.write("$L = strings.TrimSpace($L)", operand, operand);
        }

        String value = "";
        switch (targetShape.getType()) {
            case STRING:
                if (targetShape.hasTrait(EnumTrait.class)) {
                    value = String.format("types.%s(%s)", targetShape.getId().getName(), operand);
                    return value;
                }
                // MediaType strings must be base-64 encoded when sent in headers.
                if (targetShape.hasTrait(MediaTypeTrait.class)) {
                    writer.addUseImports(SmithyGoDependency.BASE64);
                    writer.write("b, err := base64.StdEncoding.DecodeString($L)", operand);
                    writer.write("if err != nil { return err }");
                    return "string(b)";
                }
                return operand;
            case ENUM:
                value = String.format("types.%s(%s)", targetShape.getId().getName(), operand);
                return value;
            case BOOLEAN:
                writer.addUseImports(SmithyGoDependency.STRCONV);
                writer.write("vv, err := strconv.ParseBool($L)", operand);
                writer.write("if err != nil { return err }");
                return "vv";
            case TIMESTAMP:
                writer.addUseImports(SmithyGoDependency.SMITHY_TIME);
                HttpBindingIndex bindingIndex = context.getModel().getKnowledge(HttpBindingIndex.class);
                TimestampFormatTrait.Format format = bindingIndex.determineTimestampFormat(
                        memberShape,
                        binding.getLocation(),
                        Format.HTTP_DATE
                );
                switch (format) {
                    case EPOCH_SECONDS:
                        writer.addUseImports(SmithyGoDependency.STRCONV);
                        writer.write("f, err := strconv.ParseFloat($L, 64)", operand);
                        writer.write("if err != nil { return err }");
                        writer.write("t := smithytime.ParseEpochSeconds(f)");
                        break;
                    case HTTP_DATE:
                        writer.write("t, err := smithytime.ParseHTTPDate($L)", operand);
                        writer.write("if err != nil { return err }");
                        break;
                    case DATE_TIME:
                        writer.write("t, err := smithytime.ParseDateTime($L)", operand);
                        writer.write("if err != nil { return err }");
                        break;
                    default:
                        throw new CodegenException("Unexpected timestamp format " + format);
                }
                return "t";
            case BYTE:
                writer.addUseImports(SmithyGoDependency.STRCONV);
                writer.write("vv, err := strconv.ParseInt($L, 0, 8)", operand);
                writer.write("if err != nil { return err }");
                return "int8(vv)";
            case SHORT:
                writer.addUseImports(SmithyGoDependency.STRCONV);
                writer.write("vv, err := strconv.ParseInt($L, 0, 16)", operand);
                writer.write("if err != nil { return err }");
                return "int16(vv)";
            case INTEGER:
            case INT_ENUM:
                writer.addUseImports(SmithyGoDependency.STRCONV);
                writer.write("vv, err := strconv.ParseInt($L, 0, 32)", operand);
                writer.write("if err != nil { return err }");
                return "int32(vv)";
            case LONG:
                writer.addUseImports(SmithyGoDependency.STRCONV);
                writer.write("vv, err := strconv.ParseInt($L, 0, 64)", operand);
                writer.write("if err != nil { return err }");
                return "vv";
            case FLOAT:
                writer.addUseImports(SmithyGoDependency.STRCONV);
                writer.write("vv, err := strconv.ParseFloat($L, 32)", operand);
                writer.write("if err != nil { return err }");
                return "float32(vv)";
            case DOUBLE:
                writer.addUseImports(SmithyGoDependency.STRCONV);
                writer.write("vv, err := strconv.ParseFloat($L, 64)", operand);
                writer.write("if err != nil { return err }");
                return "vv";
            case BIG_INTEGER:
                writer.addUseImports(SmithyGoDependency.BIG);
                writer.write("i := big.NewInt(0)");
                writer.write("bi, ok := i.SetString($L,0)", operand);
                writer.openBlock("if !ok {", "}", () -> {
                    writer.write(
                            "return fmt.Error($S)",
                            "Incorrect conversion from string to BigInteger type"
                    );
                });
                return "*bi";
            case BIG_DECIMAL:
                writer.addUseImports(SmithyGoDependency.BIG);
                writer.write("f := big.NewFloat(0)");
                writer.write("bd, ok := f.SetString($L,0)", operand);
                writer.openBlock("if !ok {", "}", () -> {
                    writer.write(
                            "return fmt.Error($S)",
                            "Incorrect conversion from string to BigDecimal type"
                    );
                });
                return "*bd";
            case BLOB:
                writer.addUseImports(SmithyGoDependency.BASE64);
                writer.write("b, err := base64.StdEncoding.DecodeString($L)", operand);
                writer.write("if err != nil { return err }");
                return "b";
            case SET:
            case LIST:
                // handle list/Set as target shape
                MemberShape targetValueListMemberShape = CodegenUtils.expectCollectionShape(targetShape).getMember();
                return getHttpHeaderCollectionDeserializer(context, writer, targetValueListMemberShape,
                        binding,
                        operand);
            default:
                throw new CodegenException("unexpected shape type " + targetShape.getType());
        }
    }