Download a file from database

[John Carroll]

Hi
I am trying to download a file from a database.  
I have searched the forum and could not find what i was looking for.  

I have a url link in the gsp pointing to the download action in the controller.
Firefox opens the file browser, and asks me to choose location to save file.  When i open the downloaded file it contains error messages from eclipse.  What am i doing wrong?



def download = {
        /* fileObj  is an instance of the domain class */  
        FileUpload fileObj = FileUpload.get(params.id)


        def file = new File(fileObj.id)
       
 
        String sFileName = fileObj.fileName
        response.setHeader("Content-Type", "application/octet-stream;")
             response.setHeader("Content-Disposition", "attachment; filename=\"" + sFileName + "\"")
        response.setHeader("Content-Length", "${file.size()}")
        response.outputStream << file.newInputStream()

        redirect(action:list)
}

[houbie]

CarrollJ wrote

I am trying to download a file from a database.  
...
FileUpload fileObj = FileUpload.get(params.id)
        def file = new File(fileObj.id)

From looking at the code, I assume that you only keep the filename in the database while the file itself is an ordinary file with fileObj.id as name. Is the file you're sending in the first place correct ('println file.getAbsolutePath()  + file.exists()')?
It would also be better to explicitly set the path of the files iso of depending on the working dir of your webserver.

Ivo

[John Carroll]

houbie wrote

CarrollJ wrote

I am trying to download a file from a database.  
...
FileUpload fileObj = FileUpload.get(params.id)
        def file = new File(fileObj.id)

From looking at the code, I assume that you only keep the filename in the database while the file itself is an ordinary file with fileObj.id as name. Is the file you're sending in the first place correct ('println file.getAbsolutePath()  + file.exists()')?
It would also be better to explicitly set the path of the files iso of depending on the working dir of your webserver.

Ivo

Thanks for replying.

The file itself is stored as blob in the database.  e.g
+-----------+--------------+------+-----+---------+----------------+
| Field     | Type         | Null | Key | Default | Extra          |
+-----------+--------------+------+-----+---------+----------------+
| id        | bigint(20)   | NO   | PRI | NULL    | auto_increment |
| version   | bigint(20)   | NO   |     |         |                |
| file_name | varchar(255) | NO   |     |         |                |
| the_file  | longblob     | NO  |     |    |                |
+-----------+--------------+------+-----+---------+----------------+

How can i pass that file to the client from the database?  

[Josh Reed]

Hi CarrolJ,

It doesn't look like anywhere in your code you actually take the  
contents of the blob ("the_file") and send it to the user.  I see you  
do something like
def file = new File(fileObj.id)
but that doesn't actually create a file with the contents from the  
database (unless Grails is doing some magic I'm not aware of).  Maybe  
you can try something like:
response.outputStream << fileObj.theFile
or something along those lines.

Cheers,
Josh

---
Josh Reed
ANDRILL IT Specialist
Tel.: [phone]
Cell: [phone]
Email: [hidden email]

ANDRILL Science Management Office
126 Bessey Hall
University of Nebraska-Lincoln
Lincoln, NE  68588-0341
Fax: [phone]
URL: http://andrill.org

On Apr 7, 2008, at 9:12 AM, CarrollJ wrote:

>
>
>
> houbie wrote:
>>
>>
>> CarrollJ wrote:
>>>
>>> I am trying to download a file from a database.
>>> ...
>>> FileUpload fileObj = FileUpload.get(params.id)
>>> def file = new File(fileObj.id)
>>>
>> From looking at the code, I assume that you only keep the filename  
>> in the
>> database while the file itself is an ordinary file with fileObj.id as
>> name. Is the file you're sending in the first place correct ('println
>> file.getAbsolutePath()  + file.exists()')?
>> It would also be better to explicitly set the path of the files iso  
>> of
>> depending on the working dir of your webserver.
>>
>> Ivo
>>
>
> Thanks for replying.
>
> The file itself is stored as blob in the database.  e.g
> +-----------+--------------+------+-----+---------+----------------+
> | Field     | Type         | Null | Key | Default | Extra          |
> +-----------+--------------+------+-----+---------+----------------+
> | id        | bigint(20)   | NO   | PRI | NULL    | auto_increment |
> | version   | bigint(20)   | NO   |     |         |                |
> | file_name | varchar(255) | NO   |     |         |                |
> | the_file  | longblob     | NO  |     |    |                |
> +-----------+--------------+------+-----+---------+----------------+
>
> How can i pass that file to the client from the database?
>
> --
> View this message in context: http://www.nabble.com/Download-a-file-from-database-tp16537389p16537458.html
> Sent from the grails - user mailing list archive at Nabble.com.
>
>
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> To unsubscribe from this list, please visit:
>
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[houbie]

CarrollJ wrote

The file itself is stored as blob in the database.  e.g
+-----------+--------------+------+-----+---------+----------------+
| Field     | Type         | Null | Key | Default | Extra          |
+-----------+--------------+------+-----+---------+----------------+
| id        | bigint(20)   | NO   | PRI | NULL    | auto_increment |
| version   | bigint(20)   | NO   |     |         |                |
| file_name | varchar(255) | NO   |     |         |                |
| the_file  | longblob     | NO  |     |    |                |
+-----------+--------------+------+-----+---------+----------------+

How can i pass that file to the client from the database?  

That would be something like:
response.outputStream << fileObj.the_file.binaryStream

[John Carroll]

Hi Josh,

Thanks for the reply.   That is my problem.  It is not getting any data from the database.  The method  file.length() returns a size of 0.    I will try - response.outputStream << fileObj.theFile - and post a reply.  

Regards,
Carrollj

Josh Reed-2 wrote

Hi CarrolJ,

It doesn't look like anywhere in your code you actually take the  
contents of the blob ("the_file") and send it to the user.  I see you  
do something like
def file = new File(fileObj.id)
but that doesn't actually create a file with the contents from the  
database (unless Grails is doing some magic I'm not aware of).  Maybe  
you can try something like:
response.outputStream << fileObj.theFile
or something along those lines.

Cheers,
Josh

---
Josh Reed
ANDRILL IT Specialist
Tel.: [phone]
Cell: [phone]
Email: [e-mail]

ANDRILL Science Management Office
126 Bessey Hall
University of Nebraska-Lincoln
Lincoln, NE  68588-0341
Fax: [phone]
URL: http://andrill.org

On Apr 7, 2008, at 9:12 AM, CarrollJ wrote:

>
>
>
> houbie wrote:
>>
>>
>> CarrollJ wrote:
>>>
>>> I am trying to download a file from a database.
>>> ...
>>> FileUpload fileObj = FileUpload.get(params.id)
>>> def file = new File(fileObj.id)
>>>
>> From looking at the code, I assume that you only keep the filename  
>> in the
>> database while the file itself is an ordinary file with fileObj.id as
>> name. Is the file you're sending in the first place correct ('println
>> file.getAbsolutePath()  + file.exists()')?
>> It would also be better to explicitly set the path of the files iso  
>> of
>> depending on the working dir of your webserver.
>>
>> Ivo
>>
>
> Thanks for replying.
>
> The file itself is stored as blob in the database.  e.g
> +-----------+--------------+------+-----+---------+----------------+
> | Field     | Type         | Null | Key | Default | Extra          |
> +-----------+--------------+------+-----+---------+----------------+
> | id        | bigint(20)   | NO   | PRI | NULL    | auto_increment |
> | version   | bigint(20)   | NO   |     |         |                |
> | file_name | varchar(255) | NO   |     |         |                |
> | the_file  | longblob     | NO  |     |    |                |
> +-----------+--------------+------+-----+---------+----------------+
>
> How can i pass that file to the client from the database?
>
> --
> View this message in context: http://www.nabble.com/Download-a-file-from-database-tp16537389p16537458.html
> Sent from the grails - user mailing list archive at Nabble.com.
>
>
> ---------------------------------------------------------------------
> To unsubscribe from this list, please visit:
>
>    http://xircles.codehaus.org/manage_email
>
>


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[John Carroll]

CarrollJ wrote

Hi Josh,

Thanks for the reply.   That is my problem.  It is not getting any data from the database.  The method  file.length() returns a size of 0.    I will try - response.outputStream << fileObj.theFile - and post a reply.  

Regards,
Carrollj

Hi Josh

I can download from the database now.  I removed the code where i was trying to make a file.  response.outputStream << fileObj.theFile works fine.  Thanks for the help all  

CarrollJ

Josh Reed-2 wrote

Hi CarrolJ,

It doesn't look like anywhere in your code you actually take the  
contents of the blob ("the_file") and send it to the user.  I see you  
do something like
def file = new File(fileObj.id)
but that doesn't actually create a file with the contents from the  
database (unless Grails is doing some magic I'm not aware of).  Maybe  
you can try something like:
response.outputStream << fileObj.theFile
or something along those lines.

Cheers,
Josh

---
Josh Reed
ANDRILL IT Specialist
Tel.: [phone]
Cell: [phone]
Email: [e-mail]

ANDRILL Science Management Office
126 Bessey Hall
University of Nebraska-Lincoln
Lincoln, NE  68588-0341
Fax: [phone]
URL: http://andrill.org

On Apr 7, 2008, at 9:12 AM, CarrollJ wrote:

>
>
>
> houbie wrote:
>>
>>
>> CarrollJ wrote:
>>>
>>> I am trying to download a file from a database.
>>> ...
>>> FileUpload fileObj = FileUpload.get(params.id)
>>> def file = new File(fileObj.id)
>>>
>> From looking at the code, I assume that you only keep the filename  
>> in the
>> database while the file itself is an ordinary file with fileObj.id as
>> name. Is the file you're sending in the first place correct ('println
>> file.getAbsolutePath()  + file.exists()')?
>> It would also be better to explicitly set the path of the files iso  
>> of
>> depending on the working dir of your webserver.
>>
>> Ivo
>>
>
> Thanks for replying.
>
> The file itself is stored as blob in the database.  e.g
> +-----------+--------------+------+-----+---------+----------------+
> | Field     | Type         | Null | Key | Default | Extra          |
> +-----------+--------------+------+-----+---------+----------------+
> | id        | bigint(20)   | NO   | PRI | NULL    | auto_increment |
> | version   | bigint(20)   | NO   |     |         |                |
> | file_name | varchar(255) | NO   |     |         |                |
> | the_file  | longblob     | NO  |     |    |                |
> +-----------+--------------+------+-----+---------+----------------+
>
> How can i pass that file to the client from the database?
>
> --
> View this message in context: http://www.nabble.com/Download-a-file-from-database-tp16537389p16537458.html
> Sent from the grails - user mailing list archive at Nabble.com.
>
>
> ---------------------------------------------------------------------
> To unsubscribe from this list, please visit:
>
>    http://xircles.codehaus.org/manage_email
>
>


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