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need advice on parsing image data

 [1/10] from: ryan::christiansen::intellisol::com at: 27-Apr-2001 15:28


When I post a form entry and a file using multipart/form-data encoding, I get the following.... -----------------------------7d1a92c9014c Content-Disposition: form-data; name="content" content -----------------------------7d1a92c9014c Content-Disposition: form-data; name="file"; filename="D: \fgonews\ad_graphic_01.jpg" Content-Type: image/pjpeg (plus a whole bunch more characters that I am unable to copy-and-paste) -----------------------------7d1a92c9014c-- This is an easy parse. However, REBOL will not parse the image data. It gets stuck when it reaches an unknown character, which shows up in Notepad as a square. As you can see, I'm not even able to copy-and-paste the actual image data from the text file into this e-mail. Does anyone have any advice on how to parse this image data? Ryan C. Christiansen Web Developer Intellisol International 4733 Amber Valley Parkway Fargo, ND 58104 701-235-3390 ext. 6671 FAX: 701-235-9940 http://www.intellisol.com Global Leader in People Performance Software _____________________________________ Confidentiality Notice This message may contain privileged and confidential information. If you think, for any reason, that this message may have been addressed to you in error, you must not disseminate, copy or take any action in reliance on it, and we would ask you to notify us immediately by return email to [ryan--christiansen--intellisol--com]

 [2/10] from: brett:codeconscious at: 28-Apr-2001 15:02


Hi Ryan, I got the post-data file from the url of your earlier message. I'm no expert but here's my thinking. 1) The data returned from the post should initially be treated as binary - because you have image data that is binary and has not been encoded. So what I did was use read/binary to get your post-data file. I don't know for sure, but it is possible some clients may upload the file data in a different encoding like Base 64 rather than straight binary. So you may need to handle the case where a content-transfer-encoding header is given. 2) Though you data is binary doesn't mean you can't parse it like a string. Just remember to use /all refinement of parse. I already had some mime type handling stuff for emails. So I changed around a little bit to handle your file as well. It is very possible I still haven't handled the RFCs properly but it seems to work at the moment. Using Rebo/View Try this script - The view part is just to show that I succesfully got your image data. do http://www.codeconscious.com/rebol-library/message-tools.r post-data: read/binary http://www.fargonews.com/post-data r: decode-mime-parts mime-parts? post-data ---------------------------7d1a92c9014c write/binary %tf.jpg r/7/content view layout [image %tf.jpg] BTW I'd like to know how to display the image without having to write the file first - anyone - please? Hope it helps you. Brett Handley ----- Original Message ----- From: <[ryan--christiansen--intellisol--com]> To: <[rebol-list--rebol--com]> Sent: Saturday, April 28, 2001 6:28 AM Subject: [REBOL] need advice on parsing image data When I post a form entry and a file using multipart/form-data encoding, I get the following.... -----------------------------7d1a92c9014c Content-Disposition: form-data; name="content" content -----------------------------7d1a92c9014c Content-Disposition: form-data; name="file"; filename="D: \fgonews\ad_graphic_01.jpg" Content-Type: image/pjpeg (plus a whole bunch more characters that I am unable to copy-and-paste) -----------------------------7d1a92c9014c-- This is an easy parse. However, REBOL will not parse the image data. It gets stuck when it reaches an unknown character, which shows up in Notepad as a square. As you can see, I'm not even able to copy-and-paste the actual image data from the text file into this e-mail. Does anyone have any advice on how to parse this image data? Ryan C. Christiansen Web Developer Intellisol International 4733 Amber Valley Parkway Fargo, ND 58104 701-235-3390 ext. 6671 FAX: 701-235-9940 http://www.intellisol.com Global Leader in People Performance Software _____________________________________ Confidentiality Notice This message may contain privileged and confidential information. If you think, for any reason, that this message may have been addressed to you in error, you must not disseminate, copy or take any action in reliance on it, and we would ask you to notify us immediately by return email to [ryan--christiansen--intellisol--com]

 [3/10] from: brett:codeconscious at: 28-Apr-2001 21:11


Me again. I realised a few holes in my script. And your problem has given my some angst with my message-tools.r script. When dealing with emails we can use import-email which assumes that the email has been read with a READ. The read does the line termination conversion. So ok. But your post data file has shown that to deal with binary data I would have to deal with CRLF line termination ( RFC1521 appendix G talks about this). So now I'm somewhat confused as to what I should do to get my message-tools.r script handle mime-emails and mime-forms. Argh! Brett. ----- Original Message ----- From: "Brett Handley" <[brett--codeconscious--com]> To: <[rebol-list--rebol--com]> Sent: Saturday, April 28, 2001 3:02 PM Subject: [REBOL] Re: need advice on parsing image data Hi Ryan, I got the post-data file from the url of your earlier message. I'm no expert but here's my thinking. 1) The data returned from the post should initially be treated as binary - because you have image data that is binary and has not been encoded. So what I did was use read/binary to get your post-data file. I don't know for sure, but it is possible some clients may upload the file data in a different encoding like Base 64 rather than straight binary. So you may need to handle the case where a content-transfer-encoding header is given. 2) Though you data is binary doesn't mean you can't parse it like a string. Just remember to use /all refinement of parse. I already had some mime type handling stuff for emails. So I changed around a little bit to handle your file as well. It is very possible I still haven't handled the RFCs properly but it seems to work at the moment. Using Rebo/View Try this script - The view part is just to show that I succesfully got your image data. do http://www.codeconscious.com/rebol-library/message-tools.r post-data: read/binary http://www.fargonews.com/post-data r: decode-mime-parts mime-parts? post-data ---------------------------7d1a92c9014c write/binary %tf.jpg r/7/content view layout [image %tf.jpg] BTW I'd like to know how to display the image without having to write the file first - anyone - please? Hope it helps you. Brett Handley ----- Original Message ----- From: <[ryan--christiansen--intellisol--com]> To: <[rebol-list--rebol--com]> Sent: Saturday, April 28, 2001 6:28 AM Subject: [REBOL] need advice on parsing image data When I post a form entry and a file using multipart/form-data encoding, I get the following.... -----------------------------7d1a92c9014c Content-Disposition: form-data; name="content" content -----------------------------7d1a92c9014c Content-Disposition: form-data; name="file"; filename="D: \fgonews\ad_graphic_01.jpg" Content-Type: image/pjpeg (plus a whole bunch more characters that I am unable to copy-and-paste) -----------------------------7d1a92c9014c-- This is an easy parse. However, REBOL will not parse the image data. It gets stuck when it reaches an unknown character, which shows up in Notepad as a square. As you can see, I'm not even able to copy-and-paste the actual image data from the text file into this e-mail. Does anyone have any advice on how to parse this image data? Ryan C. Christiansen Web Developer Intellisol International 4733 Amber Valley Parkway Fargo, ND 58104 701-235-3390 ext. 6671 FAX: 701-235-9940 http://www.intellisol.com Global Leader in People Performance Software _____________________________________ Confidentiality Notice This message may contain privileged and confidential information. If you think, for any reason, that this message may have been addressed to you in error, you must not disseminate, copy or take any action in reliance on it, and we would ask you to notify us immediately by return email to [ryan--christiansen--intellisol--com]

 [4/10] from: norsepower:uswest at: 28-Apr-2001 10:43


We do have a CRLF 'word in REBOL, correct? That could help with parse. Are you saying that with multipart/form-data, Apache is generating POST data which uses CRLF- instead of newline-terminated data? -Ryan

 [5/10] from: larry:ecotope at: 28-Apr-2001 15:01


Hi Brett,
>write/binary %tf.jpg r/7/content >view layout [image %tf.jpg] >BTW I'd like to know how to display the image without having to write the
file first - anyone - please? Using your example, you can say im: load r/7/content view layout [image im] or even view layout [image load r/7/content] Cheers -Larry

 [6/10] from: brett:codeconscious at: 29-Apr-2001 10:55


Yes and Yes. As far as I can see, the official network form of the data uses CRLF (this BTW is true of POP etc). After using Rebol for a while, we may forget that a READ converts CRLF to a newline - which is not so good for binary data - hence the /binary refinement of READ. This fact escaped my memory until I read the section in the Core manul on line conversion/endings. Hence, my issue in trying to create a set of functions useful for post data and for email which we tend to acquire with a READ in Rebol (for email is shouldn't be a problem because Email generally does not handle binary data - attachments and encoded in a mail-safe form before transport). Brett.

 [7/10] from: brett:codeconscious at: 29-Apr-2001 10:45


Ah too easy. Thanks. Brett.

 [8/10] from: deryk:iitowns at: 29-Apr-2001 11:41


Brett Handley wrote:
> Ah too easy. Thanks. > Brett.
<<quoted lines omitted: 19>>
> > > > view layout [image load r/7/content]
Might be too easy, but why is load even needed at all? if in this example, r/7/content is set, known, and in memory. Simply specifying: view layout [image r/7/content] Should be sufficient. I still have yet to wrap my head around rebol. I know it is portrayed as an 'easy to learn, thought like' language but some things like this still stump me. To me, the above layout line would be the way I would think about writing it in human fashion. Deryk -- Binary/unsupported file stripped by Listar -- -- Type: application/x-pkcs7-signature -- File: smime.p7s -- Desc: S/MIME Cryptographic Signature

 [9/10] from: brett:codeconscious at: 29-Apr-2001 16:16


I hope you will excuse another of my replies to myself. I have spent quite a deal of time on the issue I mentioned earlier about line termination and I have restructured fairly deeply my script. So much so that I have deleted the %message-tools.r script from my site and replaced it with %mime-model.r which I think is a lot more sturdy as a solution. It still needs work but should be more more useful now. More comments in the code. Any comments or bugs or improvements appreciated. Brett.

 [10/10] from: ryan:christiansen:intellisol at: 30-Apr-2001 14:32


> The data returned from the post should initially be treated > as binary - because you have image data that is binary > and has not been encoded. So what I did was use read/binary > to get your post-data file.
I'm using 'read-io to retrieve the POSTed data. There is no /binary refinement for 'read-io. Since 'read-io is a "low-level read from a port" according to 'help, isn't it already retrieving the POSTed data in binary form? Ryan C. Christiansen Web Developer Intellisol International 4733 Amber Valley Parkway Fargo, ND 58104 701-235-3390 ext. 6671 FAX: 701-235-9940 http://www.intellisol.com Global Leader in People Performance Software _____________________________________ Confidentiality Notice This message may contain privileged and confidential information. If you think, for any reason, that this message may have been addressed to you in error, you must not disseminate, copy or take any action in reliance on it, and we would ask you to notify us immediately by return email to [ryan--christiansen--intellisol--com] "Brett Handley" <[brett--codecons] To: <[rebol-list--rebol--com]> cious.com> cc: Sent by: Subject: [REBOL] Re: need advice on parsing image data [rebol-bounce--re] bol.com 04/28/2001 12:02 AM Please respond to rebol-list Hi Ryan, I got the post-data file from the url of your earlier message. I'm no expert but here's my thinking. 1) The data returned from the post should initially be treated as binary - because you have image data that is binary and has not been encoded. So what I did was use read/binary to get your post-data file. I don't know for sure, but it is possible some clients may upload the file data in a different encoding like Base 64 rather than straight binary. So you may need to handle the case where a content-transfer-encoding header is given. 2) Though you data is binary doesn't mean you can't parse it like a string. Just remember to use /all refinement of parse. I already had some mime type handling stuff for emails. So I changed around a little bit to handle your file as well. It is very possible I still haven't handled the RFCs properly but it seems to work at the moment. Using Rebo/View Try this script - The view part is just to show that I succesfully got your image data. do http://www.codeconscious.com/rebol-library/message-tools.r post-data: read/binary http://www.fargonews.com/post-data r: decode-mime-parts mime-parts? post-data ---------------------------7d1a92c9014c write/binary %tf.jpg r/7/content view layout [image %tf.jpg] BTW I'd like to know how to display the image without having to write the file first - anyone - please? Hope it helps you. Brett Handley ----- Original Message ----- From: <[ryan--christiansen--intellisol--com]> To: <[rebol-list--rebol--com]> Sent: Saturday, April 28, 2001 6:28 AM Subject: [REBOL] need advice on parsing image data When I post a form entry and a file using multipart/form-data encoding, I get the following.... -----------------------------7d1a92c9014c Content-Disposition: form-data; name="content" content -----------------------------7d1a92c9014c Content-Disposition: form-data; name="file"; filename="D: \fgonews\ad_graphic_01.jpg" Content-Type: image/pjpeg (plus a whole bunch more characters that I am unable to copy-and-paste) -----------------------------7d1a92c9014c-- This is an easy parse. However, REBOL will not parse the image data. It gets stuck when it reaches an unknown character, which shows up in Notepad as a square. As you can see, I'm not even able to copy-and-paste the actual image data from the text file into this e-mail. Does anyone have any advice on how to parse this image data? Ryan C. Christiansen Web Developer Intellisol International 4733 Amber Valley Parkway Fargo, ND 58104 701-235-3390 ext. 6671 FAX: 701-235-9940 http://www.intellisol.com Global Leader in People Performance Software _____________________________________ Confidentiality Notice This message may contain privileged and confidential information. If you think, for any reason, that this message may have been addressed to you in error, you must not disseminate, copy or take any action in reliance on it, and we would ask you to notify us immediately by return email to [ryan--christiansen--intellisol--com]

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