使用Go语言编写PostgreSQL扩展

go get -u gitlab.com/microo8/plgo/plgo

plgo .

Package gitlab.com/microo8/plgo not installed
please install it with: go get -u gitlab.com/microo8/plgo/plgo

func readPlGoSource() ([]byte, error) {
  goPath := os.Getenv("GOPATH")
  if goPath == "" {
    goPath = build.Default.GOPATH // Go 1.8 and later have a default GOPATH
  }
  for _, goPathElement := range filepath.SplitList(goPath) {
        path:=filepath.Join(goPathElement, "src", "gitlab.com", "microo8", "plgo", "pl.go")
        fmt.Println(path)
    rv, err := ioutil.ReadFile(filepath.Join(goPathElement, "src", "gitlab.com", "microo8", "plgo", "pl.go"))
    if err == nil {
      return rv, nil
    } else if os.IsNotExist(err) {
      continue // try the next
    } else {
      return nil, fmt.Errorf("Cannot read plgo package: %w", err)
    }
  }
  return nil, fmt.Errorf("Package gitlab.com/microo8/plgo not installed\nplease install it with: go get -u gitlab.com/microo8/plgo/plgo")
}

GO111MODULE='off' go get -u gitlab.com/microo8/plgo/plgo

plgo .

2020/08/11 11:19:40 var/folders/3p/yypfkyxj0wv1hr9dwxrx613c0000gn/T/plgo645118958
runtime/cgo
command-line-arguments
# command-line-arguments
Undefined symbols for architecture x86_64:
  "_DirectFunctionCall1Coll", referenced from:
      _jsonb_to_datum in _x003.o
      __cgo_b7e4853c1065_Cfunc_jsonb_to_datum in _x003.o
  "_JsonbToCString", referenced from:
      _datum_to_jsonb_cstring in _x003.o
      __cgo_b7e4853c1065_Cfunc_datum_to_jsonb_cstring in _x003.o
  "_SPI_connect", referenced from:
      __cgo_b7e4853c1065_Cfunc_SPI_connect in _x003.o
     (maybe you meant: __cgo_b7e4853c1065_Cfunc_SPI_connect)
  "_SPI_execute_plan", referenced from:
      __cgo_b7e4853c1065_Cfunc_SPI_execute_plan in _x003.o
     (maybe you meant: __cgo_b7e4853c1065_Cfunc_SPI_execute_plan)
  "_SPI_finish", referenced from:
      __cgo_b7e4853c1065_Cfunc_SPI_finish in _x003.o
     (maybe you meant: __cgo_b7e4853c1065_Cfunc_SPI_finish)
  "_SPI_fname", referenced from:
      __cgo_b7e4853c1065_Cfunc_SPI_fname in _x003.o
     (maybe you meant: __cgo_b7e4853c1065_Cfunc_SPI_fname)
  "_SPI_getbinval", referenced from:
      _get_col_as_datum in _x003.o
      __cgo_b7e4853c1065_Cfunc_get_col_as_datum in _x003.o
  "_SPI_gettype", referenced from:
      __cgo_b7e4853c1065_Cfunc_SPI_gettype in _x003.o
     (maybe you meant: __cgo_b7e4853c1065_Cfunc_SPI_gettypeid, __cgo_b7e4853c1065_Cfunc_SPI_gettype )
  "_SPI_gettypeid", referenced from:
      __cgo_b7e4853c1065_Cfunc_SPI_gettypeid in _x003.o
     (maybe you meant: __cgo_b7e4853c1065_Cfunc_SPI_gettypeid)
  "_SPI_prepare", referenced from:
      __cgo_b7e4853c1065_Cfunc_SPI_prepare in _x003.o
     (maybe you meant: __cgo_b7e4853c1065_Cfunc_SPI_prepare)
  "_SPI_processed", referenced from:
      __cgohack_SPI_processed in _cgo_main.o
     (maybe you meant: __cgohack_SPI_processed)
  "_SPI_result", referenced from:
      __cgohack_SPI_result in _cgo_main.o
     (maybe you meant: __cgo_b7e4853c1065_Cfunc_SPI_result_code_string, __cgohack_SPI_result )
  "_SPI_result_code_string", referenced from:
      __cgo_b7e4853c1065_Cfunc_SPI_result_code_string in _x003.o
     (maybe you meant: __cgo_b7e4853c1065_Cfunc_SPI_result_code_string)
  "_SPI_tuptable", referenced from:
      __cgohack_SPI_tuptable in _cgo_main.o
     (maybe you meant: __cgohack_SPI_tuptable)
  "_construct_md_array", referenced from:
      _array_to_datum in _x003.o
      __cgo_b7e4853c1065_Cfunc_array_to_datum in _x003.o
  "_cstring_to_text", referenced from:
      _cstring_to_datum in _x003.o
      __cgo_b7e4853c1065_Cfunc_cstring_to_datum in _x003.o
  "_deconstruct_array", referenced from:
      _datum_to_array in _x003.o
      __cgo_b7e4853c1065_Cfunc_datum_to_array in _x003.o
  "_elog_finish", referenced from:
      _elog_notice in _x003.o
      __cgo_b7e4853c1065_Cfunc_elog_notice in _x003.o
      _elog_error.cold.1 in _x003.o
  "_elog_start", referenced from:
      _elog_notice in _x003.o
      __cgo_b7e4853c1065_Cfunc_elog_notice in _x003.o
      _elog_error.cold.1 in _x003.o
  "_get_call_expr_argtype", referenced from:
      __cgo_b7e4853c1065_Cfunc_get_call_expr_argtype in _x003.o
     (maybe you meant: __cgo_b7e4853c1065_Cfunc_get_call_expr_argtype)
  "_get_typlenbyvalalign", referenced from:
      _array_to_datum in _x003.o
      _datum_to_array in _x003.o
      __cgo_b7e4853c1065_Cfunc_array_to_datum in _x003.o
      __cgo_b7e4853c1065_Cfunc_datum_to_array in _x003.o
  "_getmissingattr", referenced from:
      _get_heap_getattr in _x003.o
  "_heap_form_tuple", referenced from:
      __cgo_b7e4853c1065_Cfunc_heap_form_tuple in _x003.o
     (maybe you meant: __cgo_b7e4853c1065_Cfunc_heap_form_tuple)
  "_heap_getsysattr", referenced from:
      _get_heap_getattr in _x003.o
  "_jsonb_in", referenced from:
      _jsonb_to_datum in _x003.o
      __cgo_b7e4853c1065_Cfunc_jsonb_to_datum in _x003.o
  "_nocachegetattr", referenced from:
      _get_heap_getattr in _x003.o
  "_palloc", referenced from:
      _bytes_to_datum in _x003.o
      __cgo_b7e4853c1065_Cfunc_bytes_to_datum in _x003.o
  "_palloc0", referenced from:
      _array_to_datum in _x003.o
      __cgo_b7e4853c1065_Cfunc_array_to_datum in _x003.o
  "_parseTypeString", referenced from:
      __cgo_b7e4853c1065_Cfunc_parseTypeString in _x003.o
     (maybe you meant: __cgo_b7e4853c1065_Cfunc_parseTypeString)
  "_pg_detoast_datum", referenced from:
      _jsonb_to_datum in _x003.o
      _datum_to_array in _x003.o
      _datum_to_jsonb_cstring in _x003.o
      __cgo_b7e4853c1065_Cfunc_datum_to_array in _x003.o
      __cgo_b7e4853c1065_Cfunc_datum_to_jsonb_cstring in _x003.o
      __cgo_b7e4853c1065_Cfunc_jsonb_to_datum in _x003.o
  "_pg_detoast_datum_packed", referenced from:
      _datum_to_byteap in _x003.o
      __cgo_b7e4853c1065_Cfunc_datum_to_byteap in _x003.o
  "_text_to_cstring", referenced from:
      _datum_to_cstring in _x003.o
      __cgo_b7e4853c1065_Cfunc_datum_to_cstring in _x003.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
Cannot build package: exit status 2

CGO_LDFLAGS="-Wl,-undefined,dynamic_lookup"  plgo .

cd build
make install with_llvm=no

>>返回信息
/bin/sh Users/steven/anaconda3/envs/new/lib/pgxs/src/makefiles/../../config/install-sh -c -d '/Users/steven/anaconda3/envs/new/share/extension'
/bin/sh Users/steven/anaconda3/envs/new/lib/pgxs/src/makefiles/../../config/install-sh -c -d '/Users/steven/anaconda3/envs/new/share/extension'
/bin/sh Users/steven/anaconda3/envs/new/lib/pgxs/src/makefiles/../../config/install-sh -c -d '/Users/steven/anaconda3/envs/new/lib'
/usr/bin/install -c -m 644 .//ex1.control '/Users/steven/anaconda3/envs/new/share/extension/'
/usr/bin/install -c -m 644 .//ex1--0.1.sql  '/Users/steven/anaconda3/envs/new/share/extension/'
/usr/bin/install -c -m 755  ex1.so '/Users/steven/anaconda3/envs/new/lib/'

CREATE EXTENSION ex1;
select concatarray(array['foo','bar']);
select concatarray(array_agg(DISTINCT "Species")) from iris;
select Meh();

GO111MODULE='off' go get -u gitlab.com/microo8/plgo/plgo
CGO_LDFLAGS="-Wl,-undefined,dynamic_lookup"  plgo .
cd build
make install with_llvm=no