{"record":{"id":"84f1aa623e31f204","repo":"redis/go-redis","slug":"redis-can-t-parse-reply-t-reading-string","errorCode":null,"errorMessage":"redis: can't parse reply=%T reading string","messagePattern":"redis: can't parse reply=%T reading string","errorType":"exception","errorClass":null,"httpStatus":null,"severity":"error","filePath":"command.go","lineNumber":8753,"sourceCode":"\t\t}\n\t}\n\treturn &VectorScoreSliceSliceCmd{\n\t\tbaseCmd: cmd.cloneBaseCmd(),\n\t\tval:     val,\n\t}\n}\n\nfunc readVectorAttribStringOrNil(rd *proto.Reader) (*string, error) {\n\tv, err := rd.ReadReply()\n\tif err != nil {\n\t\tif err == proto.Nil {\n\t\t\treturn nil, nil\n\t\t}\n\t\treturn nil, err\n\t}\n\ts, ok := v.(string)\n\tif !ok {\n\t\treturn nil, fmt.Errorf(\"redis: can't parse reply=%T reading string\", v)\n\t}\n\treturn &s, nil\n}\n\ntype VectorAttribSliceCmd struct {\n\tbaseCmd\n\n\tval []VectorAttrib\n}\n\nvar _ Cmder = (*VectorAttribSliceCmd)(nil)\n\nfunc NewVectorAttribSliceCmd(ctx context.Context, args ...any) *VectorAttribSliceCmd {\n\treturn &VectorAttribSliceCmd{\n\t\tbaseCmd: baseCmd{\n\t\t\tctx:  ctx,\n\t\t\targs: args,\n\t\t},","sourceCodeStart":8735,"sourceCodeEnd":8771,"githubUrl":"https://github.com/redis/go-redis/blob/c5cad058c72f58370553b48566302303cf8a2e89/command.go#L8735-L8771","documentation":"This helper converts a parsed RESP value into a *string and errors when the value's Go type is not string. It is used by vector-set attribute parsing (e.g. VGETATTR); a non-string reply (nil, integer, byte slice from a custom reader) cannot be assigned, so this error surfaces.","triggerScenarios":"Calling VGetAttr() (or any path using this string reader at command.go:~8753) where the RESP reply decodes to a non-string type — e.g. a nil bulk string versus an actual value.","commonSituations":"Requesting an attribute that does not exist and the server replying with a null the client maps to non-string; RESP2/RESP3 encoding differences; custom dialer/reader wrappers altering types.","solutions":["Verify the attribute exists on the element (VGETATTR key element) before fetching it in Go.","Check nil handling: if the attribute may be absent, treat the nil reply as 'not found' rather than a string.","Upgrade go-redis to the latest version for improved null/type handling in vector commands.","Inspect the raw reply with redis-cli to confirm the server returns a bulk string."],"exampleFix":"// before: attribute missing -> nil reply -> type error\nattr, err := rdb.VGetAttr(ctx, \"pts\", \"elem\", \"color\")\n// redis: can't parse reply=<nil> reading string\n\n// after: check existence first\nemb, _ := rdb.VEmb(ctx, \"pts\", \"elem\", false)\nif emb != nil {\n    attr, err := rdb.VGetAttr(ctx, \"pts\", \"elem\", \"color\")\n}","handlingStrategy":"type-guard","validationCode":"exists, err := rdb.VEmb(ctx, \"pts\", \"elem\", false).Result()\nif err != nil || exists == nil {\n    // element missing; skip attribute fetch\n}","typeGuard":"func asStringReply(v interface{}) (*string, bool) {\n    s, ok := v.(string)\n    if !ok { return nil, false }\n    return &s, true\n}","tryCatchPattern":"attr, err := rdb.VGetAttr(ctx, \"pts\", \"elem\", \"color\")\nif err != nil {\n    if strings.Contains(err.Error(), \"can't parse reply\") {\n        // treat as missing/unsupported attribute\n    }\n    return err\n}","preventionTips":["Check element/attribute existence before VGetAttr","Handle nil replies as 'attribute not found'","Use RESP3 for consistent null semantics","Keep go-redis current for null-handling fixes"],"tags":["redis","vectorset","type-conversion","reply-parsing"],"backgroundTag":"unexpected-reply-type","analyzedSha":"c5cad058c72f58370553b48566302303cf8a2e89","analyzedAt":"2026-09-01T06:50:53.388Z","contentChangedAt":null,"schemaVersion":2},"datasetVersion":"2026-09-08T10:18:20.063Z"}