| 1 | NOTES ON VERSION COMPATIBILITY |
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| 2 | |
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| 3 | This file attempts to document the compatibility issues between |
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| 4 | different Subversion clients and servers. More specifically, where we |
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| 5 | want to change our (WebDAV) protocol usage in an incomptabile way, and |
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| 6 | our stepwise plan towards rolling out that change. |
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| 7 | |
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| 8 | |
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| 9 | BINARY PROPERTIES |
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| 10 | ================= |
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| 11 | |
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| 12 | Change: to signify that a property is binary, we will add an attribute |
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| 13 | onto the property element that specifies its encoding (base64 |
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| 14 | or standard XML entity escaping). |
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| 15 | |
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| 16 | Problem: old clients and servers will not be looking for this |
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| 17 | attribute, and will not decode the contents appropriately. |
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| 18 | |
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| 19 | The current plan from issue 1015: |
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| 20 | --------------- |
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| 21 | Okay, I've decided to propagate this functionality in three stages, |
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| 22 | with a couple of milestones between each stage: |
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| 23 | |
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| 24 | (1) server and client learn to recognize and handle the new |
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| 25 | 'V:encoding' attribute on properties. at this point, no binary |
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| 26 | properties will actually be coming across the ra-dav wire. (0.20 |
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| 27 | milestone) |
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| 28 | |
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| 29 | (2) server starts to transmit non-XML-safe properties with the |
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| 30 | 'V:encoding="base64"' attribute and the property value |
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| 31 | base64-encoded. during this interim period, clients will be to get |
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| 32 | binary properties from the server, but will not be able to commit |
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| 33 | new or modified binary properties. (0.21 milestone) |
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| 34 | |
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| 35 | (3) clients starts to transmit non-XML-safe properties with the |
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| 36 | 'V:encoding="base64"' attribute and the property value |
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| 37 | base64-encoded. this is the moment of full support. (0.22 |
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| 38 | milestone) |
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| 39 | |
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| 40 | All the code for full support will be in place, but disabled |
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| 41 | functionality will be wrapped in SVN_DAV_FEATURE_BINARY_PROPS |
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| 42 | #defines. |
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| 43 | |
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| 44 | When stage 2 is ready to go into 0.21, we just remove the #defines |
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| 45 | from the code in mod_dav_svn, commit, and reset this issue to have a |
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| 46 | 0.24 milestone. |
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| 47 | |
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| 48 | When stage 3 is ready to go into 0.22, we just remove the #defines |
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| 49 | from the code in libsvn_ra_dav, lose the #define itself from |
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| 50 | svn_dav.h, commit, and close this issue. |
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| 51 | --------------- |
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| 52 | |
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| 53 | |
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| 54 | REPOSITORY UUIDS |
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| 55 | ================ |
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| 56 | |
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| 57 | Change: |
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| 58 | |
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| 59 | Problem: |
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| 60 | |
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| 61 | Plan: |
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| 62 | |
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| 63 | |
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| 64 | PROPERTY NAMESPACES |
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| 65 | =================== |
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| 66 | |
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| 67 | Change: |
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| 68 | |
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| 69 | Problem: |
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| 70 | |
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| 71 | Plan: |
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| 72 | |
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| 73 | |
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| 74 | HANDLING OF UNKNOWN XML ELEMENTS |
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| 75 | ================================ |
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| 76 | |
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| 77 | Change: |
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| 78 | |
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| 79 | Problem: |
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| 80 | |
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| 81 | Plan: |
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| 82 | |
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| 83 | [note: need to review any "else" conditions to ensure we don't fall |
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| 84 | into them for unknown/future props; some if constructs might have |
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| 85 | assumed only (say) three elements were possible, so only tested for |
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| 86 | two of them, and fell to the else for the third] |
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