Jean Vandromme

Yes, thanks though !

You were right (again, like always 🙂

I add in my GET call in angular an option for content:

  httpOptions = {
    headers: new HttpHeaders({
      'Content-Type': 'application/json',
      'Accept': 'application/json'
    })
  }  

  getEmployees(): Observable<any> {
    return this.http.get<any>('http://localhost:8080/rest/default/maindata/employees', this.httpOptions)
    .pipe(
      tap(data => console.log(data))
    );
  }

and now, I get a correct json array in angular:

I still don't understand why it is necessary in one case and not the other ?

Thanks again,

Hope it will help others

There's a DOMException with message 'Microsoft MSXML is not installed' ?

MSXML 3,4,5 and 6 are installed

I run a Windows 10 Family OS

Here are the 2 printscreens:

with array:

without:

The differences between the 2 responses (array vs no array) from MARS is the content-type:

with array: Content-Type=*/*

without array: Content-Type=text/plain; charset=ISO-8859-1

Here is the XHR request

curl "http://localhost:8080/rest/default/maindata/employees" -H "Accept: application/json, text/plain, */*" -H "Referer: http://localhost:4200/employees-list" -H "Origin: http://localhost:4200" -H "User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.131 Safari/537.36" --compressed

I try since several days now to get a json array from a dataset query from a MARS server (FiredacBasic demo)

If I use a simple dataset like this:

[GET, Path('/employees'), Produces(TMediaType.APPLICATION_JSON), IsReference]
function getEmployees: TFDDataSet;

function TMainDataResource.getEmployees: TFDDataSet;
begin
  Result := qEmployees;
end;

I get this in chrome:

this in Postman:

this error in Angular with a simple call like this:

  getEmployees(): Observable<Employee> {
    return this.http.get<Employee>('http://localhost:8080/rest/default/maindata/employees')
    .pipe(
      tap(data => console.log(data))
    );
  }

If I use a datasets array:

[GET, Path('/employees'), Produces(TMediaType.APPLICATION_JSON), IsReference]
 function getEmployees: TArray<TFDDataSet>;

function TMainDataResource.getEmployees: TArray<TFDDataSet>;
begin
  Result := [qEmployees];
end;

I get this in chrome:

this in postman:

and no error in angular:

Any clue how to solve this ?

Thanks

Hi,

It seems I have the same problem you had but can't solve it.

How did you pratically get it solved ?

CORS is activated but I keep getting an internal server error in angular but not in Postman

I get my json array in chrome also without any issues, so ...

Thanks a lot

Jean

Thanks Andrea but it seems I have to do something more to get rid of a 500 server error.

I try to acces the FireDac server demo through an angular frontend. I had first a CORS problem which is now resolved. But now I have a 500 internal error server when a I try a simple get for the employee table.

I can access it with Postman without any problem. 

I add this in the Form.create of server.forms.main.pas:

  // MARS-Curiosity Engine
  FEngine := TMARSEngine.Create;
  try
    FEngine.Parameters.LoadFromIniFile;
    FEngine.AddApplication('DefaultApp', '/default', ['Server.*']);
    PortNumberEdit.Text := FEngine.Port.ToString;
    TMARSFireDAC.LoadConnectionDefs(FEngine.Parameters, 'FireDAC');

    FEngine.BeforeHandleRequest :=
    function (const AEngine: TMARSEngine;
      const AURL: TMARSURL; const ARequest: IMARSRequest; const AResponse: IMARSResponse;
      var Handled: Boolean
    😞 Boolean
    begin
      //Result := True;
      if SameText(AURL.Document, 'favicon.ico') then
      begin
        Result := False;
        Handled := True;
      end;

      // Handle CORS and PreFlight
      if SameText(ARequest.Method, 'OPTIONS') then
      begin
        Handled := True;
        Result := False;
      end;

      Result := True;
    end;

    StartServerAction.Execute;
  except
    FreeAndNil(FEngine);
    raise;
  end;
 

This is the headers response in POSTMAN

Hi Andrea,

I try to decomment the preflight request sample in server.ignition.pas of the WebTemplate demo but got an error:

[dcc32 Error] Server.Ignition.pas(80): E2010 Incompatible types: 'TBeforeHandleRequestProc' and 'Procedure'

What do I do wrong ?

Thanks

Jean Vandromme

Hi Andrea,

Thanks a lot, I know where I have to go now. I will loose some interesting MARS features doing so but if it's the only way.

The problem with the 2d approach is that I have tables with a lot of columns (more than 100), and I thought I could avoid making models for all of them.

One thing though, what do you mean by TRecord<TItem>.ToDataset implementation ? Is it a Firedac thing or a MARS thing ?

Thanks

Jean

Hi,

I would like to develop a frontend using Angular.

I have a MARS server, which works well for GET calls with a FB FireDac DB. Since my frontend isn't a delphi client, I use a simple json format and not json/firedac input/output.

I struggle a little bit with the POST calls. I try to post with POSTMAN. Which json format do I have to use to get an update of my DB ?

For now, I have a 'Database not found' from my server.

Part of my code:

type
  [Path('/maindata')]
  TMainDataResource = class(TMARSFDDataModuleResource)
    FDGUIxWaitCursor1: TFDGUIxWaitCursor;
    qItems: TFDQuery;
    qOneItem: TFDQuery;
    conDB: TFDConnection;
  private
  protected
    [Context] FD: TMARSFireDAC;
  public
    [GET, Path('/allItems'), Produces(TMediaType.APPLICATION_JSON), IsReference]
    function getAllItems: TArray<TFDDataSet>;
    [POST, Path('/allItems'), Consumes(TMediaType.APPLICATION_JSON), IsReference]
    function postAllItems([BodyParam] const ADeltas: TArray<TFDMemTable>):TArray<TMARSFDApplyUpdatesRes>;
    [GET, Path('/oneItem'), Produces(TMediaType.APPLICATION_JSON), IsReference]
    function getOneItem: TArray<TFDDataSet>;
    [POST, Path('/oneItem'), Consumes(TMediaType.APPLICATION_JSON), IsReference]
    function postOneItem([BodyParam] const ADeltas: TArray<TFDMemTable>):TArray<TMARSFDApplyUpdatesRes>;
  end;

implementation

{%CLASSGROUP 'Vcl.Controls.TControl'}

{$R *.dfm}

uses
  MARS.Core.Registry;

{ TMainDataResource }

function TMainDataResource.getAllItems: TArray<TFDDataSet>;
begin
  Result := [qItems];
end;

function TMainDataResource.postAllItems([BodyParam] const ADeltas: TArray<TFDMemTable>):TArray<TMARSFDApplyUpdatesRes>;
begin
  Result:=FD.ApplyUpdates([qItems], ADeltas);
end;

function TMainDataResource.getOneItem: TArray<TFDDataSet>;
begin
  FD.InjectParamValues(TFDAdaptedDataSet(qOneItem).Command);
  Result := [qOneItem];
end;

function TMainDataResource.postOneItem([BodyParam] const ADeltas: TArray<TFDMemTable>):TArray<TMARSFDApplyUpdatesRes>;
begin
  Result:=FD.ApplyUpdates([qOneItem], ADeltas);
end;

The json structure for POST:

{

  "qItems": [

  {

    "id": 1,

    "name": "stuff"

  },

  {

    "id": 2,

    "name": "other stuff"

  }

  ]

}

which is in fact the same structure I get from the GET calls.

What can I do to get it work ?

Thanks,

Jean